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Temperature dependence of two or more water species in delignified wood and lignocellulosic,tracked by LFNMR relaxometry
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作者 Long Zhou Wenjing Liu +5 位作者 Zhihong Zhao Rui Tan Xiaofeng Zhu Shen Wang Zonghai Harry Xie Minghui Zhang 《Magnetic Resonance Letters》 2026年第1期13-24,共12页
Distributions of nuclear magnetic resonance(NMR)relaxation times provide detailed information about the water in wood.This study documents the water dynamics analysis of T_(2)and T_(1)distributions for saturated delig... Distributions of nuclear magnetic resonance(NMR)relaxation times provide detailed information about the water in wood.This study documents the water dynamics analysis of T_(2)and T_(1)distributions for saturated delignified sapwood(DSW),delignified heartwood(DHW)and lignocellulose(LC)samples at different temperatures.Results indicate that below the freezing point of bulk water,free water freezes,causing its signal to disappear from the distribution.Then,the low temperature distributions of the unfrozen bound water contain more information about its components,with DSW,DHW and LC containing two distinct states of bound water(OH bound water(B-water)and more freely bound water(C-water)).Furthermore,it was observed that within the temperature range of−3°C to−60°C,B-water in DSW,DHW and LC maintained a higher unfrozen water content(UWC)value than C-water,and the T_(1)/T_(2)ratios for B-water were consistently higher than that for C-water,indicating that B-water has a greater antifreeze capacity.T_(2)and T_(1)distributions offer different kinds of information about water components,and all peaks within the distribution have been assigned. 展开更多
关键词 Low-field nuclear magnetic resonance (LFNMR) Delignified wood and lignocellulosic Water species Relaxation characteristics Bound water Temperature dependence
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Environmental epidemiology of infectious diseases in the post-COVID-19 era:mechanisms,evidence,and future directions
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作者 Bo Cao Kun-Yi Wu +1 位作者 Ting La Nan Xu 《Infectious Diseases Research》 2026年第1期23-37,共15页
Global environmental changes including climate warming,extreme weather events,ambient air pollution,freshwater contamination,and landscape transformation are reshaping the epidemiology of infectious diseases with unpr... Global environmental changes including climate warming,extreme weather events,ambient air pollution,freshwater contamination,and landscape transformation are reshaping the epidemiology of infectious diseases with unprecedented complexity,particularly in the post-COVID-19 era.This review synthesizes evidence from the past decade(2015-2024)to systematically elucidate how key environmental drivers modulate pathogen emergence,transmission dynamics,and clinical outcomes,with a focus on underlying mechanistic pathways.Specifically,we highlight:(1)the temperature-and precipitation-dependent transmission of vector-borne diseases(e.g.,malaria,dengue)via expanded vector habitats and accelerated pathogen incubation;(2)the exacerbation of respiratory infections(including COVID-19)by particulate matter(PM2.5)and nitrogen dioxide(NO2)through impaired mucosal immunity and enhanced inflammatory responses;(3)the persistence of diarrheal diseases in low-and middle-income countries(LMICs)linked to water insecurity and climate-induced infrastructure failure;and(4)zoonotic spillover risks amplified by urbanization and deforestation-driven human-wildlife interface disruption.Integrating the One Health socioecological framework,we further summarize methodological advances from high-resolution genomic surveillance to climate-informed machine learning models that have improved causal inference and predictive accuracy.Our synthesis confirms that environmental factors are not merely contextual but central,modifiable determinants of infectious disease risk,with disproportionate impacts on vulnerable populations.To mitigate future threats,we emphasize the urgency of interdisciplinary collaboration,integrated environmental-health monitoring platforms,and climate-resilient public health policies tailored to post-pandemic challenges.This review provides a timely roadmap for translating environmental epidemiology insights into actionable strategies to strengthen global health resilience. 展开更多
关键词 infectious disease environmental epidemiology COVID-19 one health climate change
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Polymorphism of SG13S114T/A in the ALOX5AP Gene and the Risk for Stroke in a Large Chinese Cohort 被引量:10
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作者 ZHANG Wei-Li YANG Xiao-Min +2 位作者 SHI Jia SUN Kai HUI Ru-Tai 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2006年第8期678-684,共7页
The 5-1ipoxygenase activating protein,an important regulator in the biosynthesis of proinflammatory leukotrienes,has been reported to confer risks for cardiovascular diseases and stroke.The purpose of this study is to... The 5-1ipoxygenase activating protein,an important regulator in the biosynthesis of proinflammatory leukotrienes,has been reported to confer risks for cardiovascular diseases and stroke.The purpose of this study is to assess whether genetic variants in the ALOX5AP encoding the 5-1ipoxygenase activating protein will influence the risk for stroke in the Chinese population.A total of 1773 patients with stroke and 1713 controls were recruited from seven clinical centers.Polymorphisms of SG13S114T/A and SG13S89G/A in the ALOX5AP were genotyped by the polymerase chain reaction and the restriction enzyme analysis.The multivariate logistic regression model was used to exclude the influence of the conventional vascular risk factors on stroke.The frequency of SG13S114A allele in the ALOX5AP was significantly higher in male patients with thrombotic stroke(33.6%)than in controls(29.2%;P=0.014).The SG13S 114AA genotype was significantly associated with a 1.62-fold risk for thrombotic stroke in men(95%confidence interval,1.11 to 2.35;P=0.012).The SG13S89G/A variant was not associated with stroke or its subtypes.Haplotype analysis showed no significant differences between stroke patients and controls.The present study suggested that a common genetic variant SG13Sll4T/A in the ALOX5AP gene is associated with an increased risk for atherothrombotic stroke in Chinese males,and racial differences in allele and genotype frequencies may account partially for the different association findings between populations. 展开更多
关键词 LEUKOTRIENES 5-1ipoxygenase activating protein genetics risk factors STROKE
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The reproductive toxicity of saponins isolated from Cortex Albiziae in female mice 被引量:6
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作者 SHU Yang CAO Mei +7 位作者 YIN Zhong-Qiong LI Ping LI Tai-Qiang LONG Xing-Fa ZHU Lian-Fa JIA Ren-Yong DAI Shu-Jun ZHAO Jian 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第2期119-126,共8页
Saponin frsom Cortex Albiziae(SCA) are extensively used in the clinical treatment of tumor and depression. However, SCA may cause several adverse effects, including reproductive toxicity. The present study was designe... Saponin frsom Cortex Albiziae(SCA) are extensively used in the clinical treatment of tumor and depression. However, SCA may cause several adverse effects, including reproductive toxicity. The present study was designed to assess the mechanism by which SCA cause reproductive toxicity in female mice. The general reproductive toxicity testing was accomplished in female Kunming mice. The animals were divided into four groups: three groups that were treated by oral gavage with 135, 270, and 540 mg·kg-1·d-1 of SCA prepared in physiological saline, respectively, and one vehicle control group that was treated with physiological saline only. The gestational toxicity tests were conducted at 540 mg·kg-1·d-1. The general reproductive toxicity results showed that the pregnancy rate of the SCA-treated group decreased with the pregnancy rate being decreased by 70% at 540 mg·kg-1·d-1. SCA elicited maternal toxicity in the ovary and the uterus, but no fetal toxicity or teratogenicity was observed. The rates of implantation in the early, middle, and late pregnancy were all decreased, with stillbirths and maternal deaths being observed. Histopathological changes showed that SCA adversely affected the ovary and the uterus. In conclusion, SCA-induced reproductive toxicity in female mice is most likely caused by its damage to the ovary and the uterus. 展开更多
关键词 SAPONIN CORTEX Albiziae FEMALE mice REPRODUCTIVE TOXICITY
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In vivo genome editing thrives with diversified CRISPR technologies 被引量:6
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作者 Xun Ma Avery Sum-Yu Wong +3 位作者 Hei-Yin Tam Samuel Yung-Kin Tsui Dittman Lai-Shun Chung Bo Feng 《Zoological Research》 SCIE CAS CSCD 2018年第2期58-71,共14页
Prokaryotic type II adaptive immune systems have been developed into the versatile CRISPR technology, which has been widely applied in site- specific genome editing and has revolutionized biomedical research due to it... Prokaryotic type II adaptive immune systems have been developed into the versatile CRISPR technology, which has been widely applied in site- specific genome editing and has revolutionized biomedical research due to its superior efficiency and flexibility. Recent studies have greatly diversified CRISPR technologies by coupling it with various DNA repair mechanisms and targeting strategies. These new advances have significantly expanded the generation of genetically modified animal models, either by including species in which targeted genetic modification could not be achieved previously, or through introducing complex genetic modifications that take multiple steps and cost years to achieve using traditional methods. Herein, we review the recent developments and applications of CRISPR-based technology in generating various animal models, and discuss the everlasting impact of this new progress on biomedical research. 展开更多
关键词 CRISPR/Cas9 Genome editing Animal models
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Prediction model of in-hospital mortality in elderly patients with acute heart failure based on retrospective study 被引量:9
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作者 Qian JIA Yu-Rong WANG +5 位作者 Ping HE Xue-Liang HUANG Wei YAN Yang MU Ktm-Lun HE Ya-Ping TIAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第11期669-678,共10页
Objectives The aim of this study was to develop a clinical risk model that is predictive of in-hospital mortality in elderly patients hos- pitalized with acute heart failure (AHF). Methods 2486 patients who were 60 ... Objectives The aim of this study was to develop a clinical risk model that is predictive of in-hospital mortality in elderly patients hos- pitalized with acute heart failure (AHF). Methods 2486 patients who were 60 years and older from intensive care units of Cardiology De- partment in the hospital were analyzed. Independent risk factors for in-hospital mortality were obtained by binary logistic regression and then used to establish the risk prediction score system (RPSS). The area under the curve (AUC) of receiver operator characteristic and C-statistic test were adopted to assess the performance of RPSS and to compare with previous get with the guidelines-heart failure (GWTG-HF). Re- sults By binary logistic regression analysis, heart rate (OR: 1.043, 95% CI: 1.030-1.057, P 〈 0.001), left ventricular ejection fraction (OR: 0.918, 95% CI: 0.833~).966, P 〈 0.001), pH value (OR: 0.001, 95% CI: 0.000-0.002, P 〈 0.001), renal dysfunction (OR: 0.120, 95% CI: 0.066M).220, P 〈 0.001) and NT-pro BNP (OR: 3.463, 95% CI: 1.870-6.413, P 〈 0.001) were independent risk factors of in-hospital mortal- ity for elderly AHF patients. Additionally, RPSS, which was composed of all the above-mentioned parameters, provided a better risk predic- tion than GWTG-THF (AUC: 0.873 vs. 0.818, P = 0.016). Conclusions Our risk prediction model, RPSS, provided a good prediction for in-hospital mortality in elderly patients with A/IF. 展开更多
关键词 Acute heart failure N-hospital mortality Prediction model Risk factors
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Predictive value of K-ras and PIK3CA in non-small cell lung cancer patients treated with EGFR-TKIs: a systemic review and meta-analysis 被引量:7
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作者 Jie-Ying Chen Ya-Nan Cheng +5 位作者 Lei Han Feng Wei Wen-Wen Yu Xin-Wei Zhang Shui Cao Jin-Pu Yu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2015年第2期126-139,共14页
Objective: A meta-analysis was performed to augment the insufficient data on the impact of mutative EGFR downstream phosphatidylinositol-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways on the... Objective: A meta-analysis was performed to augment the insufficient data on the impact of mutative EGFR downstream phosphatidylinositol-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways on the clinical efficiency of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment of non-small cell lung cancer (NSCLC) patients. Methods: Network databases were explored in April, 2015. Papers that investigated the clinical outcomes of NSCLC patients treated with EGFR-TKIs according to the status of K-ras and/or PIK3CA gene mutation were included. A quantitative meta-analysis was conducted using standard statistical methods. Odds ratios (ORs) for objective response rate (ORR) and hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS) were calculated. Results: Mutation in K-ras significantly predicted poor ORR [OR =0.22; 95% confidence interval (CI), 0.13-0.35], shorter PFS (HR =1.56; 95% CI, 1.27-1.92), and shorter OS (HR =1.59; 95% CI, 1.33-1.91) in NSCLC patients treated with EGFR-TKIs. Mutant PIK3CA significantly predicted shorter OS (HR =1.83; 95% CI, 1.05-3.20), showed poor ORR (OK =0.70; 95% CI, 0.22-2.18), and shorter PFS (HR = 1.79; 95% CI, 0.91-3.53) in NSCLC patients treated with EGFR-TKIs. Conclusion: K-ras mutation adversely affected the clinical response and survival of NSCLC patients treated with EGFR- TKIs. PIK3CA mutation showed similar trends. In addition to EGFR, adding K-ras and PIK3CA as routine gene biomarkers in clinical genetic analysis is valuable to optimize the effectiveness of EGFR-TKI regimens and identify optimal patients who will benefit from EGFR-TKI treatment. 展开更多
关键词 Non-small cell lung cancer (NSCLC) tyrosine kinase inhibitor (TKI) targeted therapy K-RAS PIK3CA META-ANALYSIS
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Microstructure Characterization of a Biogenic Shale Gas Formation——Insights from the Antrim Shale,Michigan Basin 被引量:2
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作者 Kouqi Liu Natalia Zakharova +3 位作者 Thomas Gentzis Adedoyin Adeyilola Humberto Carvajal-Ortiz Hallie Fowler 《Journal of Earth Science》 SCIE CAS CSCD 2020年第6期1229-1240,共12页
Biogenic gas shales,predominantly microbial in origin,form an important class of organicrich shale reservoirs with a significant economic potential.Yet large gaps remain in the understanding of their gas generation,st... Biogenic gas shales,predominantly microbial in origin,form an important class of organicrich shale reservoirs with a significant economic potential.Yet large gaps remain in the understanding of their gas generation,storage,and transport mechanisms,as previous studies have been largely focused on mature thermogenic shale reservoirs.In this study,the pore structure of 18 Antrim Shale samples was characterized using gas adsorption(CO2 and N2).The results show that most of the Antrim Shale samples are rich in organic matter content(0.58 wt.%to 14.15 wt.%),with highest values found in the Lachine and Norwood members.Samples from the Paxton Member,characterized by lower organic content,have smaller micropore surface area and micropore volume but larger meso-macro pore surface area and volume.The deconvolution results of the pore size distribution from the N2 adsorption indicate that all of the tested Antrim Shale samples have similar pore groups.Organic matter in the Antrim Shale hosts micro pores instead of meso-macro pores,while clay minerals host both micro and meso-macro pores.Mineralrelated pores play a primary role in the total porosity.The biogenic Antrim Shale,therefore,has different pore structures from other well-studied thermogenic gas shales worldwide. 展开更多
关键词 gas adsorption Antrim Shale biogenic shale organic matter
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Relationship of serum polyunsaturated fatty acids with cytokines in colorectal cancer 被引量:2
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作者 He-Jin Jia Peng-Jun Zhang +3 位作者 Yu-Lan Liu Chao-Guang Jiang Xu Zhu Ya-Ping Tian 《World Journal of Gastroenterology》 SCIE CAS 2016年第8期2524-2532,共9页
AIM: To investigate the relationship of serum levels of polyunsaturated fatty acid(PUFA) with kinds of cytokines in colorectal cancer(CRC).METHODS: Serum samples of 100 CRC patients were collected. The concentration o... AIM: To investigate the relationship of serum levels of polyunsaturated fatty acid(PUFA) with kinds of cytokines in colorectal cancer(CRC).METHODS: Serum samples of 100 CRC patients were collected. The concentration of total n-3 PUFA which included C18:3 n-3, C20:5 n-3, C22:5 n-3, C22:6 n-3 and the total n-6 PUFA included C18:2 n-6, C18:3 n-6, C20:3 n-6, C20:4 n-6, and C22:5 n-6 were detected onGC-2010 Plus Gas Chromatograph with a Omegawax TM 250 column. Cytokines were detected by Mag Plex TM-C microspheres. P values for the trend were estimated by creating a continuous variable using the median value within quartiles.RESULTS: Interleukin-6(IL-6) showed significantly positive association with the C20:4 n-6(P for trend = 0.004). Interferon gamma(IFN-γ) showed significant positive association with the C22:5 n-3(P for trend = 0.035). IL-8 and matrix metalloproteinase-9(MMP-9) showed significant inverse association with the C22:6 n-3(P for trend = 0.049, and 0.021). MMP-2 showed significant inverse association with the C20:5 n-3(P for trend = 0.008). MMP-7 showed significantly positive association with the ratio of n-6 PUFA and n-3 PUFA(P for trend = 0.008). MMP-7 also showed significantly inverse association with the ratio of C20:4 n-6 and(n-6 PUFA + n-3 PUFA)(P for trend = 0.024). IL-10(P for trend = 0.023) and IL-6(P for trend = 0.036) showed significantly positive association with the ratio of C20:4 n-6 and C20:5 n-3.CONCLUSION: Our data suggested that serum levels of PUFA is related to the inflammation of CRC, and also play different role in regulation of immune response. 展开更多
关键词 Polyunsaturated FATTY ACIDS CYTOKINE COLORECTAL cancer Odds ratio Nutrition
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Thermal maturity evaluation using Raman spectroscopy for oil shale samples of USA:comparisons with vitrinite reflectance and pyrolysis methods 被引量:2
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作者 MdGolam Kibria Souvik Das +3 位作者 Qin-Hong Hu Asish R.Basu Wen-Xuan Hu Subhadip Mandal 《Petroleum Science》 SCIE CAS CSCD 2020年第3期567-581,共15页
Thermal maturity is commonly assessed by various geochemical screening methods(e.g.,pyrolysis and organic petrology).In this contribution,we attempt to establish an alternative approach to estimating thermal maturity ... Thermal maturity is commonly assessed by various geochemical screening methods(e.g.,pyrolysis and organic petrology).In this contribution,we attempt to establish an alternative approach to estimating thermal maturity with Raman spectroscopy,using 24 North American oil shale samples with thermal maturity data generated by vitrinite reflectance(VRo%)and pyrolysis(Tmax)-based maturity calculation(VRe%).The representative shale samples are from the Haynesville(East Texas),Woodford(West Texas),Eagle Ford and Pearsall(South Texas)Formations,as well as Gothic,Mancos,and Niobrara Formation shales(all from Colorado).The Raman spectra of disordered carbonaceous matter(D1 and G bands separation)of these samples were directly obtained from the rock chips without prior sample preparation.Using the Gaussian and Lorentzian distribution approach,thermal maturities from VR were correlated with carbon G and D1.We found that the Raman band separation(RBS)displayed a better correlation for equivalent VRe%than vitrinite reflectance VRo%.The RBS(D1–G)distance versus total organic carbon,free hydrocarbons from thermal extraction(S1),and the remaining hydrocarbon generating potential(S2)indicate that the RBS(D1–G)distance is also related to kerogen type.Data presented here from three methods of maturity determination of shale demonstrate that Raman spectroscopy is a quick and valid approach to thermal maturity assessment. 展开更多
关键词 US shale Raman spectroscopy Vitrinite reflectance Thermal maturity
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Prediction of early-stage hepatocellular carcinoma using Onco Scan chromosomal copy number aberration data 被引量:2
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作者 Ming-Chin Yu Chao-Wei Lee +5 位作者 Yun-Shien Lee Jang-Hau Lian Chia-Lung Tsai Yi-Ping Liu Chun-Hsing Wu Chi-Neu Tsai 《World Journal of Gastroenterology》 SCIE CAS 2017年第44期7818-7829,共12页
AIM To identify chromosomal copy number aberrations(CNAs) in early-stage hepatocellular carcinoma(HCC) and analyze whether they are correlated with patient prognosis.METHODS One hundred and twenty patients with early-... AIM To identify chromosomal copy number aberrations(CNAs) in early-stage hepatocellular carcinoma(HCC) and analyze whether they are correlated with patient prognosis.METHODS One hundred and twenty patients with early-stage HCC were enrolled in our study, with the collection of formalin fixed, paraffin-embedded(FFPE) specimens and clinicopathological data. Tumor areas were marked by certified pathologists on a hematoxylin and eosinstained slide, and cancer and adjacent non-cancerous tissues underwent extraction of DNA, which was analyzed with the Affymetrix Onco Scan platform to assess CNAs and loss of heterozygosity(LOH). Ten individuals with nonmalignant disease were used as the control group. Another cohort consisting of 40 patients with stage Ⅰ/Ⅱ HCC were enrolled to analyze gene expression and to correlate findings with the Onco Scan data.RESULTS Copy number amplifications occurred at chromosomes 1 q21.1-q44 and 8 q12.3-24.3 and deletions were found at 4 q13.1-q35.2, 8 p 23.2-21.1, 16 q23.3-24.3, and 17 p13.3-12, while LOH commonly occurred at 1 p32.3, 3 p21.31, 8 p23.2-21.1, 16 q22.1-24.3, and 17 p 13.3-11 in early-stage HCC. Using Cox regression analysis, we also found that a higher percentage of genome change(≥ 60%) was an independent factor for worse prognosis in early-stage HCC(P = 0.031). Among the 875 genes in the Onco Scan Gene Chip, six were independent predictors of worse disease-free survival, of which three were amplified(MYC, ELAC2, and SYK) and three were deleted(GAK, MECOM, and WRN). Further, patients with HCC who exhibited ≥ 3 CNAs involving these six genes have worse outcomes compared to those who had < 3 CNAs(P < 0.001). Similarly, Asian patients with stage I HCC from The Cancer Genome Atlas harboring CNAs with these genes were also predicted to have poorer outcomes.CONCLUSION Patients with early-stage HCC and increased genome change or CNAs involving MYC, ELAC2, SYK, GAK, MECOM, or WRN are at risk for poorer outcome after resection. 展开更多
关键词 Early-stage hepatocellular carcinoma Copy number aberration Prognosis Onco Scan Molecular inversion probe
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Genetic variations in the SMAD4 gene and gastric cancer susceptibility 被引量:3
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作者 Dong-Mei Wu Hai-Xia Zhu +6 位作者 Qing-Hong Zhao Zhi-Zhong Zhang Shi-Zhi Wang Mei-Lin Wang Zheng-Dong Zhang Wei-Da Gong Ming Tan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第44期5635-5641,共7页
AIM:To explore the association between mothers against decapentaplegic homolog 4 (SMAD4) gene polymorphisms and gastric cancer risk.METHODS:Five tagging single nucleotide polymor-phisms (tSNPs) in the SMAD4 gene were ... AIM:To explore the association between mothers against decapentaplegic homolog 4 (SMAD4) gene polymorphisms and gastric cancer risk.METHODS:Five tagging single nucleotide polymor-phisms (tSNPs) in the SMAD4 gene were selected and genotyped in 322 gastric cancer cases and 351 cancerfree controls in a Chinese population by using the polymerase chain reactionrestriction fragment length polymorphism method.Immunohistochemistry was used to examine SMAD4 protein expression in 10 normal gastric tissues adjacent to tumors.RESULTS:In the single-locus analysis,two significantly decreased risk polymorphisms for gastric cancer were observed:the SNP3 rs17663887 TC genotype (adjusted odds ratio=0.38,95% confidence interval:0.21-0.71),compared with the wild-type TT genotype and the SNP5 rs12456284 GG genotype (0.31,0.16-0.60),and with the wild-type AA genotype.In the combined analyses of these two tSNPs,the combined genotypes with 2-3 protective alleles (SNP3 C and SNP5 G allele) had a significantly decreased risk of gastric cancer (0.28,0.16-0.49) than those with 0-1 protective allele.Furthermore,individuals with 0-1 protective allele had significantly decreased SMAD4 protein expression levels in the norma tissues adjacent to tumors than those with 2-3 protective alleles (P=0.025).CONCLUSION:These results suggest that genetic variants in the SMAD4 gene play a protective role in gastric cancer in a Chinese population. 展开更多
关键词 Mothers against decapentaplegic homolog 4 Genetic variation Gastric tumor Molecular epidemiology
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Maceral evolution of lacustrine shale and its effects on the development of organic pores during low mature to high mature stage:A case study from the Qingshankou Formation in northern Songliao Basin,northeast China 被引量:2
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作者 Liu Wang Bo Liu +4 位作者 Long-Hui Bai Mehdi Ostadhassan Thomas Gentzis Bo-Yang Wang Yi-Zhang Wang 《Petroleum Science》 SCIE EI CSCD 2023年第5期2709-2725,共17页
Organic matter(OM)hosted pores are crucial for the storage and migration of petroleum in shale reservoirs.Thermal maturity and macerals type are important factors controlling the development of pores therein.In this s... Organic matter(OM)hosted pores are crucial for the storage and migration of petroleum in shale reservoirs.Thermal maturity and macerals type are important factors controlling the development of pores therein.In this study,six lacustrine shale samples with different thermal maturities from the first member of the Qingshankou Formation in the Songliao Basin,of which vitrinite reflectance(R_(o))ranging from 0.58% to 1.43%,were selected for a comparative analysis.Scanning electron microscopy(SEM)and reflected light microscopy were combined to investigate the development of organic pores in different macerals during thermal maturation.The results show that alginite and liptodetrinite are the dominant primary macerals,followed by bituminite.Only a few primary organic pores developed in the alginite at the lowest maturity(R_(o)=0.58%).As a result of petroleum generation,oil-prone macerals began to transform to initial-oil solid bitumen at the early oil window(R_(o)=0.73%)and shrinkage cracks were observed.Initial-oil solid bitumen cracked to oil,gas and post-oil bitumen by primary cracking(R_(o)=0.98%).Moreover,solid bitumen(SB)was found to be the dominant OM when R_(o)>0.98%,which indicates that SB is the product of oil-prone macerals transformation.Many secondary bubble pores were observed on SB,which formed by gas release,while devolatilization cracks developed on migrated SB.Additionally,at the late oil window(Ro?1.16%),migrated SB filled the interparticle pore spaces.With further increase in temperature,the liquid oil underwent secondary cracking into pyrobitumen and gas,and spongy pores developed on the pyrobitumen at higher levels of maturity(Ro=1.43%),which formed when pyrobitumen cracked into gas.Vitrinite and inertinite are stable without any visible pores over the range of maturities,verifying their low petroleum generation potential.In addition,it was concluded that clay minerals could have a catalytic effect on the petroleum generation,which may explain why organicclay mixtures had more abundant pores than single OM particles.However,after R_(o)>0.98%,authigenic minerals occupied the organic pore spaces on the organic-clay mixtures,resulting in fewer pores compared to those observed in samples at the early to peak oil window. 展开更多
关键词 Lacustrine shale Maceral evolution Organic pores Scanning electron microscopy Reflected light microscopy
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Comparative Investigation of Alternative Negative Staining Reagents in Bacterial Morphological Study 被引量:1
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作者 Masaaki Minami Hiroshi Takase 《Journal of Biosciences and Medicines》 2017年第10期17-24,共8页
Negative staining is an effective method that can be used for electron microscopic study to observe fine structural morphology without destruction of bacterial structure. Although uranium acetate is used worldwide as ... Negative staining is an effective method that can be used for electron microscopic study to observe fine structural morphology without destruction of bacterial structure. Although uranium acetate is used worldwide as a general dyeing solution, it is extremely difficult to use it by a new purchase at a research institution because it falls under the nuclear regulation substance in Japan. Therefore, we examined alternative reagents for negative staining that could replace uranium acetate through bacterial observation with an electron microscope. Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pyogenes were examined by four stain reagents (phosphotungstic acid (PTA), EMstainer, TI blue, and uranium acetate). Pre cultured bacteria were stained with each stain reagents on a copper grid, washed with PBS, and observed with a transmission electron microscope. In the comparison between bacterial structures, the cell wall structure and bacterial flagella could be observed well in the order of PTA, EMstainer, and uranium acetate. With TI blue staining, flagella could be observed very poorly. In comparison between bacteria, gram negative bacteria such as Escherichia coli and Pseudomonas aeruginosa, could be observed well as compared with gram positive cocci such as Staphylococcus aureus and Streptococcus pyogenes. The uranium acetate looked very coarse in background particles. Since crystals tend to precipitate, TI blue also required filtering, and electron beams were absorbed by the agglomerated crystals, and the frequency of electronic burning occurred high frequency. In this study, there was clear difference in the observation conditions depending on the type of bacteria and the kind of the staining reagents. Especially, it was confirmed that good negative staining features of Pseudomonas aeruginosa by electron microscope were obtained by PTA and EMstainer staining. These alternative reagents are considered to be a candidate for a negative staining. 展开更多
关键词 NEGATIVE STAINING Electron MICROSCOPE BACTERIAL MICROMORPHOLOGY Phosphotungstic Acid EMstainer
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Identification of speckle-type POZ protein somatic mutations in African American prostate cancer 被引量:2
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作者 Eric Buckles Chiping Qian +6 位作者 Andrew Tadros Sumana Majumdar Jennifer Cvitanovic Jovanny Zabaleta John Estrada John Wilson Wanguo Liu 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第6期829-832,共4页
The speckle-type POZ protein (SPOP) is a tumor suppressor in prostate cancer (PCa). SPOP somatic mutations have been reported in up to 15% of PCa of those of European descent. However, the genetic roles of SPOP in... The speckle-type POZ protein (SPOP) is a tumor suppressor in prostate cancer (PCa). SPOP somatic mutations have been reported in up to 15% of PCa of those of European descent. However, the genetic roles of SPOP in African American (AA)-PCa are currently unknown. We sequenced the SPOP gene to identify somatic mutations in 49 AA prostate tumors and identified three missense mutations (p.Y87C, p.F102S, and p.G111E) in five AA prostate tumors (10%) and one synonymous variant (p.11061) in one tumor. Intriguingly, all of mutations and variants clustered in exon six, and all of the mutations altered conserved amino acids. Moreover, two mutations (p.F102S and p.G111E) have only been identified in AA-PCa to date. Quantitative real-time polymerase chain reaction analysis showed a lower level of SPOP expression in tumors carrying SPOP mutations than their matched normal prostate tissues. In addition, SPOP mutations and novel variants were detected in 5 of 27 aggressive PCa and one of 22 less aggressive PCa (P 〈 0.05). Further studies with increased sample size are needed to validate the clinicopathological significance of these SPOP mutations in AA-PCa. 展开更多
关键词 African American mutation analysis prostate cancer speckle-type POZ protein
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An optimized procedure for plant recovery from somatic embryos significantly facilitates the genetic improvement of Vitis 被引量:1
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作者 Zhijian T Li Kyung-Hee Kim +3 位作者 Sadanand A Dhekney Jonathan R Jasinski Matthew R Creech Dennis J Gray 《Horticulture Research》 SCIE 2014年第1期183-189,共7页
Plant regeneration from grapevine(Vitis spp.)via somatic embryogenesis typically is poor.Recovery of plants from Vitis rotundifolia Michx.(muscadine grape)is particularly problematic due to extremely low efficiency,in... Plant regeneration from grapevine(Vitis spp.)via somatic embryogenesis typically is poor.Recovery of plants from Vitis rotundifolia Michx.(muscadine grape)is particularly problematic due to extremely low efficiency,including extended culture durations required for embryo–plant conversion.Poor plant recovery is an obstacle to the selection of improved genetically modified lines.Somatic embryos(SEs)of V.rotundifolia cultivar Delicious(Del-HS)and Vitis vinifera L cultivar Thompson Seedless(TS)were used to identify culture media and conditions that promoted embryo differentiation and plant conversion;this resulted in a two-step culture system.In comparative culture experiments,C2D medium containing 6%sucrose was the most effective,among four distinct formulae tested,for inducing precocious SE germination and cell differentiation.This medium,further supplemented with 4 mM 6-benzylaminopurine(C2D4B),was subsequently determined to enhance post-germinative growth of SE.MS medium supplemented with 0.5 mM 1-naphthaleneacetic acid(MSN)was then utilized to stimulate root and shoot growth of germinated SE.An average of 35%and 80%‘Del-HS’and‘TS’SE,respectively,developed into plants.All plants developed robust root and shoot systems and exhibited excellent survival following transfer to soil.Over 150 plants of‘Del-HS’were regenerated and established within 2.5 months,which is a dramatic reduction from the 6-to 12-month time period previously required.Similarly,88‘TS’plant lines were obtained within the same time period.Subsequently,seven out of eight Vitis cultivars exhibited significantly increased plant conversion percentages,demonstrating broad application of the two-step culture system to produce the large numbers of independent plant lines needed for selection of desired traits. 展开更多
关键词 CULTIVAR VITIS CULTURE
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Optimal concentration of mesenchymal stem cells for fracture healing in a rat model with long bone fracture 被引量:2
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作者 Myung-Seo Kim Hyun-Ju Chung Kang-Il Kim 《World Journal of Stem Cells》 SCIE 2022年第12期839-850,共12页
BACKGROUND There is still no consensus on which concentration of mesenchymal stem cells(MSCs)to use for promoting fracture healing in a rat model of long bone fracture.AIM To assess the optimal concentration of MSCs f... BACKGROUND There is still no consensus on which concentration of mesenchymal stem cells(MSCs)to use for promoting fracture healing in a rat model of long bone fracture.AIM To assess the optimal concentration of MSCs for promoting fracture healing in a rat model.METHODS Wistar rats were divided into four groups according to MSC concentrations:Normal saline(C),2.5×10^(6)(L),5.0×10^(6)(M),and 10.0×10^(6)(H)groups.The MSCs were injected directly into the fracture site.The rats were sacrificed at 2 and 6 wk post-fracture.New bone formation[bone volume(BV)and percentage BV(PBV)]was evaluated using micro-computed tomography(CT).Histological analysis was performed to evaluate fracture healing score.The protein expression of factors related to MSC migration[stromal cell-derived factor 1(SDF-1),transforming growth factor-beta 1(TGF-β1)]and angiogenesis[vascular endothelial growth factor(VEGF)]was evaluated using western blot analysis.The expression of cytokines associated with osteogenesis[bone morphogenetic protein-2(BMP-2),TGF-β1 and VEGF]was evaluated using real-time polymerase chain reaction.RESULTS Micro-CT showed that BV and PBV was significantly increased in groups M and H compared to that in group C at 6 wk post-fracture(P=0.040,P=0.009;P=0.004,P=0.001,respectively).Significantly more cartilaginous tissue and immature bone were formed in groups M and H than in group C at 2 and 6 wk post-fracture(P=0.018,P=0.010;P=0.032,P=0.050,respectively).At 2 wk post fracture,SDF-1,TGF-β1 and VEGF expression were significantly higher in groups M and H than in group L(P=0.031,P=0.014;P<0.001,P<0.001;P=0.025,P<0.001,respectively).BMP-2 and VEGF expression were significantly higher in groups M and H than in group C at 6 wk postfracture(P=0.037,P=0.038;P=0.021,P=0.010).Compared to group L,TGF-β1 expression was significantly higher in groups H(P=0.016).There were no significant differences in expression levels of chemokines related to MSC migration,angiogenesis and cytokines associated with osteogenesis between M and H groups at 2 and 6 wk post-fracture.CONCLUSION The administration of at least 5.0×10^(6)MSCs was optimal to promote fracture healing in a rat model of long bone fractures. 展开更多
关键词 Rat model Femoral shaft fracture Mesenchymal stem cells Direct injection Optimal concentration Fracture healing
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Insulin exerts direct, IGF-1 independent actions in growth plate chondrocytes 被引量:1
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作者 Fengjie Zhang Qiling He +3 位作者 Wing Pui Tsang W Timothy Garvey Wai Yee Chan Chao Wan 《Bone Research》 SCIE CAS 2014年第2期121-130,共10页
Insufficient insulin production or action in diabetic states is associated with growth retardation and impaired bone healing, while the underling mechanisms are unknown. In this study, we sought to define the role of ... Insufficient insulin production or action in diabetic states is associated with growth retardation and impaired bone healing, while the underling mechanisms are unknown. In this study, we sought to define the role of insulin signaling in the growth plate. Insulin treatment of embryonic metatarsal bones from wild-type mice increased chondrocyte proliferation. Mice lacking insulin receptor (IR) selectively in chondrocytes (CartIR-/-) had no discernable differences in total femoral length compared to control littermates. However, CartIR-/- mice exhibited an increase in chondrocyte numbers in the growth plate than that of the controls. Chondrocytes lacking IR had elevated insulin-like growth factor (IGF)-IR mRNA and protein levels. Subsequently, IGF-1 induced phosphorylafion of Akt and ERK was enhanced, while this action was eliminated when the cells were treated with IGF-1R inhibitor Picropodophyllin. Deletion of the IR impaired chondrogenic differentiation, and the effect could not be restored by treatment of insulin, but partially rescued by IGF-1 treatment. Intriguingly, the size of hypertrophic chondrocytes was smaller in CartIR-/- mice when compared with that of the control littermates, which was associated with upregnlation of tuberous sclerosis complex 2 (TSC2). These results suggest that deletion of the IR in chondrocytes sensitizes IGF-1R signaling and action, IR and IGF-1R coordinate to regulate the proliferation, differentiation and hypertrophy of growth plate chondrocytes. 展开更多
关键词 IGF-1 independent actions in growth plate chondrocytes Insulin exerts direct
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复发性自然流产妇女血中膜联蛋白A5水平降低及膜联蛋白A5抗凝活性抵抗 被引量:1
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作者 Rand J.H. Arslan A.A. 李奎 《世界核心医学期刊文摘(妇产科学分册)》 2006年第4期12-12,共1页
Objective: We investigated whether levels of annexin A5,evidence for resistance to annexin A5 activity, and levels antiannexin A5 antibodies might be altered in women with a history of recurrent spontaneous pregnancy ... Objective: We investigated whether levels of annexin A5,evidence for resistance to annexin A5 activity, and levels antiannexin A5 antibodies might be altered in women with a history of recurrent spontaneous pregnancy losses. Study design: These annexin A5 parameters were assayed in 70 nonpregnant women with a history of ≥3 recurrent spontaneous pregnancy losses (cases) and 50 women without adverse pregnancy history (control subjects). Results: Cases had significantly lower plasma annexin A5 levels than control subjects (median, 4.7 ng/mL [range, 0.3-40.4 ng/mL] vs 6.7 ng/mL [range, 0.7-56.0]; P = .01), significantly reduced anticoagulant ratios (188%[range, 119%-279%] vs 238%[range, 159%-286%]; P < .0001), and reduced binding of annexin A5 to phospholipid (6.3 ng/aliquot phospholipid [range, 1.5-16.4 ng/aliquot phospholipid] vs 9.7 ng/aliquot phospholipid (range, 3.5-17.0 ng/aliquot phospholipid]; P = .0002). There were no significant differences in anti-annexin A5 antibody levels. Conclusion: Reduction of annexin A5 and interference with its anticoagulant and binding activities are associated significantly with a history of recurrent spontaneous pregnancy losses. These data support the concept of a significant role for annexin A5 in the maintenance of pregnancy. 展开更多
关键词 自然流产 膜联蛋白 A5 抗凝活性 妊娠史 非孕妇女 研究设计 结合活性
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Functional integration of newly generated neurons into striatum following cerebral ischemia in adult rat brain 被引量:2
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作者 Shang-Wei Hou Yong-Quan Wang +6 位作者 Ming Xu Di-Han Shen Lin-Mei Zhang Ji-Jiang ang Fang Huang Zhang Yu Feng-Yan Sun 《中国药理通讯》 2008年第3期12-13,共2页
关键词 神经元 大脑 临床分析 缺血症
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