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Virus Location and Lymphocyte Apoptosis in Lymph Nodes of Piglets Infected with PCV-2 被引量:1
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作者 SHI Lū-juan HAN Hui-li ZHANG Shu-xia 《Agricultural Sciences in China》 CAS CSCD 2008年第4期507-512,共6页
The present study has been performed to understand the location of the virus, type of apoptotic cells, and their relation to lymph nodes of piglets infected with porcine circovirus type Ⅱ (PCV-2). Nine 32-day-old c... The present study has been performed to understand the location of the virus, type of apoptotic cells, and their relation to lymph nodes of piglets infected with porcine circovirus type Ⅱ (PCV-2). Nine 32-day-old conventional piglets free of infection with PCV-2 were used, and distributed into three groups: control group (n = 3), piglets inoculated with PCV-2 alone (PCV-2, n = 3), and PCV-2 inoculated and KLH immunostimulated group (PCV-2 + KLH, n = 3). Superficial inguinal lymph nodes from all piglets were collected for histological examination after 32 days postinoculation, and immunohistochemistry for PCV-2 detection. Location of apoptotic cells was detected with TdT-mediated dUTP nick end labeling (TUNEL) and cell cycle, and the apoptotic rates were measured by flow cytometry. The characteristic histopathological lesions of the piglets in PCV-2 and PCV-2 + KLH were lymphocyte depletions in the cortex and paracortex of the lymph nodes, epithelioid-like macrophage infiltration, and intracytoplasmic inclusion bodies presented in epithelioid-like macrophages. PCV-2 was mainly found in epithelioid-like macrophages by immunohistochemistry. In the lymph nodes, lymphocytes presented higher apoptotic rates in the cortex by TUNEL, special B-cell areas, and similar apoptotic cells were found in this compartment in the control. The apoptotic rates of the lymph nodes were 0.41, 3.34, and 4.88% in the control, PCV-2, and PCV-2 + KLH groups by flow cytometry, respectively. The apoptotic rates of lymph nodes for PCV-2 and PCV-2 + KLH piglets were significantly higher than those for the control group (P〈0.05 and P〈0.01). The proliferation index (PI) was 0.17_+0.01, 0.12_+0.01 and 0.12_+0.04 in the control, PCV-2, and PCV-2 + KLH group, the PI of the control group was higher than that of the other groups, but without the statistical difference. PCV-2 can induce lymphocyte depletion in lymph nodes of piglets by blocking cell proliferation and promoting apoptosis. This is one of the mechanisms of immunosuppression on infected piglets by PCV-2. 展开更多
关键词 APOPTOSIS virus located lymph node PCV-2 PIGLETS
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基于空间模拟退火算法的NO_(2)空气监测站点优化:以闽西南城市群为例
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作者 邱月 祝鹏飞 +2 位作者 苏颖 Abiot Molla 任引 《生态学杂志》 北大核心 2025年第5期1662-1670,共9页
大气污染评价是城市规划与控制中重要组成部分,关系到人类健康和社会发展。合理布设空气质量监测站对区域空气质量分布的预测至关重要。本研究旨在评估空气监测点的最小样本容量,以表征空气NO_(2)的最优预测精度,并为预测模型建立可靠... 大气污染评价是城市规划与控制中重要组成部分,关系到人类健康和社会发展。合理布设空气质量监测站对区域空气质量分布的预测至关重要。本研究旨在评估空气监测点的最小样本容量,以表征空气NO_(2)的最优预测精度,并为预测模型建立可靠的输入。本文以中国闽西南地区地面NO_(2)监测站点优化为例,设计了基于空间模拟退火算法的空气质量监测网络空间优化的方法框架。基于空间模拟退火算法以最小克里金方差(MKV)为目标,改善监测站点的布局,提高空气污染监测的精度和效果。在优化过程中,使用了扰动算法对监测站点布局进行改变。并采用MKV进行评估(不考虑财务预算限制)寻求优化效率最高的采样数量。对地面NO_(2)空气污染监测站点的空间布局进行优化,通过优化,我们发现在增加160个监测站点后,NO_(2)的MKV从0.09μg·m^(-3)降低至0.02μg·m^(-3),预测精度提升了71.46%。这种优化可能改善监测系统的覆盖范围和采样密度,提高监测数据的准确性和可靠性。这对于及时识别和应对污染源、监测空气质量趋势以及制定环境政策至关重要。此外,该方法还有可能应用于其他形式的环境污染(如水、土壤和噪音)监测,这对今后空气监测站点的布设及管理思路提供了参考。 展开更多
关键词 监测站点布局 空间模拟退火算法 经验贝叶斯克里金插值法 no_(2)监测 布局优化 点位优化
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Evaluation of the protective effects of Crocus sativus L.against cypermethrin induced reproductive toxicity in male rats through the Nrf2 pathway and in silico ADMET analysis
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作者 Fareena Tariq Farah Ijaz +9 位作者 Yasameen Hameed Jasim Farah Naz Channa Sohail Ahmed Ahmed Shandookh Hameed Sobia Alyas Ahmed Raheem Rayshan Tahira Bibi Nazima Yousaf Khan Sadia Bibi Jameel Ahmed Buzdar 《Traditional Medicine Research》 2026年第3期12-25,共14页
Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to i... Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice. 展开更多
关键词 Crocus sativus L. CYPERMETHRIN male reproductive toxicity Nrf2 pathway in silico ADMET analysis
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含杂质超临界CO_(2)输送管道水膜生成模拟及腐蚀威胁预测 被引量:1
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作者 陈兵 张萧玉 +3 位作者 房启超 唐春丽 齐文娇 王香增 《腐蚀与防护》 北大核心 2025年第3期68-76,共9页
以延长油田一期管网工程中榆林能化-乔家洼干线CO_(2)输送管道为例,结合热力学分析了该实际管网工程中杂质水凝析过程及其腐蚀威胁,使用OLGA软件模拟了管线的水膜生成并预测了腐蚀威胁,分析了稳态工况和不同瞬态工况下水膜含量及存在位... 以延长油田一期管网工程中榆林能化-乔家洼干线CO_(2)输送管道为例,结合热力学分析了该实际管网工程中杂质水凝析过程及其腐蚀威胁,使用OLGA软件模拟了管线的水膜生成并预测了腐蚀威胁,分析了稳态工况和不同瞬态工况下水膜含量及存在位置变化,并基于试验数据验证了模拟方法的适用性。结果表明:在稳态运行过程中,该管线前22.3 km存在一定量的连续水膜,管内存在腐蚀威胁;随管线输量波动,水膜体积增加,低输量下存在水膜的管段更长;低压运行时水膜体积减少,但在压力恢复过程中,水膜体积迅速增加,被水膜覆盖的管线长度达到37 km;在停输/再启动工况下,水膜体积和存在水膜的管段长度均减小,但停输可能导致前8 km管线中的静态水膜发生聚集,造成管壁严重腐蚀;在泄漏工况下,管内水膜体积增加,存在水膜的管段长度增加至30 km,管内腐蚀威胁较大。 展开更多
关键词 超临界CO_(2) 腐蚀 水膜 存在位置
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老年男性2型糖尿病患者合并肌少-骨质疏松症相关因素研究
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作者 张任飞 董娟 +1 位作者 李悦芃 邱蕾 《老年医学与保健》 2025年第2期317-321,共5页
目的探讨老年男性2型糖尿病(T2DM)患者合并肌少--骨质疏松症(OS)的可能危险因素。方法选取2022年1月—2024年5月北京医院体检的60岁及以上老年男性T2DM患者404例。采集受试者基线信息;评估优势手握力、5次起坐时间和6 m步速;双能X射线... 目的探讨老年男性2型糖尿病(T2DM)患者合并肌少--骨质疏松症(OS)的可能危险因素。方法选取2022年1月—2024年5月北京医院体检的60岁及以上老年男性T2DM患者404例。采集受试者基线信息;评估优势手握力、5次起坐时间和6 m步速;双能X射线吸收法测定骨密度及身体成分。单因素和多因素Logistic回归法分析老年男性T2DM合并OS的影响因素。结果老年男性T2DM患者OS患病率28.96%(117/404)。多因素Logistic回归分析显示,体质量指数(OR=0.902,95%CI:0.775~0.986)、腰椎最低骨密度(OR=0.000,95%CI:0.000~0.014)及股骨颈骨密度(OR=0.001,95%CI:0.000~0.022)升高为OS的保护因素;增龄(OR=1.133,95%CI:1.052~1.257)、体脂率(OR=1.171,95%CI:1.008~1.421)升高及罹患慢性阻塞性肺疾病(OR=1.026,95%CI:1.007~1.052)为OS的危险因素。结论老年男性T2DM患者OS患病率较高,应关注体脂率较高、体质量指数与骨密度较低的高危人群。 展开更多
关键词 老年 男性 2型糖尿病 肌少--骨质疏松症
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小波降噪算法在CO_(2)管道中的泄漏精确定位
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作者 陈兵 祖江涛 +1 位作者 毕鉴 王香增 《西北大学学报(自然科学版)》 北大核心 2025年第5期956-969,共14页
负压波法适合碳捕获、利用与封存(carbon capture utilization and storage,CCUS)技术的CO_(2)管道泄漏定位检测,但超临界CO_(2)管输周边环境及管内高压产生的噪声,影响了定位的准确性。为此,选择小波变换对含噪声的压力信号进行分解降... 负压波法适合碳捕获、利用与封存(carbon capture utilization and storage,CCUS)技术的CO_(2)管道泄漏定位检测,但超临界CO_(2)管输周边环境及管内高压产生的噪声,影响了定位的准确性。为此,选择小波变换对含噪声的压力信号进行分解降噪,采用TGNET模拟软件建立CO_(2)管道泄漏模型,通过对比Botros的激波管泄放试验验证了泄漏模型的可行性。使用该泄漏模型对含噪声的压力信号进行小波降噪,再对降噪后的数据进行压差转化和互相关分析,最终得到各组压力传感器接收到压力信号的具体时间差。该泄漏模型还应用到了延长油田360000 t/a超临界CO_(2)管输方案,对人为设定的泄漏口压力噪声进行小波降噪和互相关分析。研究表明,经小波降噪后的压力信号更为稳定、精确,能够得到准确的时间差,为后续负压波法精确定位泄漏点位置提供了依据。 展开更多
关键词 CO_(2)管道 泄漏 定位 噪声 小波变换
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MicroRNA-27a-mediated repression of cysteine-rich secretory protein 2 translation in asthenoteratozoospermic patients 被引量:6
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作者 Jun-Hao Zhou Qi-Zhao Zhou +9 位作者 Jian-Kun Yang Xiao-Ming Lyu Jun Bian Wen-Bin Guo Zi-Jian Chen Ming Xia Hui Xia Tao Qi Xin Li Cun-Dong Liu 《Asian Journal of Andrology》 SCIE CAS CSCD 2017年第5期591-595,共5页
Cysteine-rich secretory protein 2 (CRISP2) is an important protein in spermatozoa that plays roles in modulating sperm flagellar motility, the acrosome reaction, and gamete fusion. Spermatozoa lacking CRISP2 exhibit... Cysteine-rich secretory protein 2 (CRISP2) is an important protein in spermatozoa that plays roles in modulating sperm flagellar motility, the acrosome reaction, and gamete fusion. Spermatozoa lacking CRISP2 exhibit low sperm motility and abnormal morphology. However, the molecular mechanisms underlying the reduction of CRISP2 in asthenoteratozoospermia (ATZ) remain unknown. In this study, low expression of CRISP2 protein rather than its mRNA was observed in the ejaculated spermatozoa from ATZ patients as compared with normozoospermic males. Subsequently, bioinformatic prediction, luciferase reporter assays, and microRNA-27a (miR-27a) transfection experiments revealed that miR-27a specifically targets CRISP2 by binding to its 3' untranslated region (3'-UTR), suppressing CRISP2 expression posttranscriptionally. Further evidence was provided by the clinical observation of high miR-27a expression in ejaculated spermatozoa from ATZ patients and a negative correlation between miR-27a expression and CRISP2 protein expression. Finally, a retrospective follow-up study supported that both high miR-27a expression and low CRISP2 protein expression were associated with low progressive sperm motility, abnormal morphology, and infertility. This study demonstrates a novel mechanism responsible for reduced CRISP2 expression in ATZ, which may offer a potential therapeutic target for treating male infertility, or for male contraception. 展开更多
关键词 asthenoteratozoospermia cysteine-rich secretory protein 2 male infertility microRNA-27a
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Novel DPY19L2 variants in globozoospermic patients and the overcoming this male infertility 被引量:10
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作者 Yong-Liang Shang Fu-Xi Zhu +9 位作者 Jie Yan Liang Chen Wen-Hao Tang Sai Xiao Wei-Ke Mo Zhi-Guo Zhang Xiao-Jin He Jie Qiao Yun-Xia Cao Wei Li 《Asian Journal of Andrology》 SCIE CAS CSCD 2019年第2期183-189,共7页
Globozoospermia has been reported to be a rare but severe causation of male infertility,which results from the failure of acrosome biogenesis and sperm head shaping.Variants of dpy-19-like 2(DPY19L2)are highly related... Globozoospermia has been reported to be a rare but severe causation of male infertility,which results from the failure of acrosome biogenesis and sperm head shaping.Variants of dpy-19-like 2(DPY19L2)are highly related to globozoospermia,but related investigations have been mainly performed in patients from Western countries.Here,we performed a screening of DPY19L2 variants in a cohort of Chinese globozoospermic patients and found that five of nine patients carried DPY19L2 deletions and the other four patients contained novel DPY19L2 point mutations,as revealed by whole-exome sequencing.Patient 3(P3)contained a heterozygous variant(c.2126+5G>A),P6 contained a homozygous nonsense mutation(c.1720C>T,p.Arg574*),P8 contained compound heterozygous variants(c.H82-1184delATCf p.Leu394_Ser395deIinsPhe;c.368A>T,p.Hisl23Arg),and P9 contained a heterozygous variant(c.H82-1184delATCTTI frameshift).We also reported intracytoplasmic sperm injection(ICSI)outcomes in the related patients,finding that ICSI followed by assisted oocyte activation(AOA)with calcium ionophore achieved high rates of live births.In summary,the infertility of these patients results from DPY19L2 dysfunction and can be treated by ICSI together with AOA. 展开更多
关键词 DPY19L2 GLOBOZOOSPERMIA male in fertility point mutation whole-exome sequencing
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Mitochondrial haplogroups associated with Japanese centenarians, Alzheimer's patients, Parkinson's patients, type 2 diabetic patients and healthy non-obese young males 被引量:4
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作者 Shigeru Takasaki 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2009年第7期425-434,共10页
The relationships between five classes of Japanese people (i.e., 96 centenarians, 96 Alzheimer's disease (AD) patients, 96 Parkinson's disease (PD) patients, 96 type 2 diabetic (T2D) patients, and 96 healthy ... The relationships between five classes of Japanese people (i.e., 96 centenarians, 96 Alzheimer's disease (AD) patients, 96 Parkinson's disease (PD) patients, 96 type 2 diabetic (T2D) patients, and 96 healthy non-obese young males) and their mitochondrial single nucleotide polymorphism (mtSNP) frequencies at individual mtDNA positions of the entire mitochondrial genome were examined using the radial basis function (RBF) network and the modified method. New findings of mitochondrial haplogroups were obtained for individual classes. The five classes of people were associated with the following haplogroups: Japanese centenarians-M7b2, D4b2a, and B5b; Japanese AD patients-G2a, B4cl, and N9b1; Japanese PD patients-M7b2, B4e, and B5b; Japanese T2D patients-B5b, M8al, G, D4, and F1; and Japanese healthy non-obese young males-D4g and D4b1b. From the points of common haplogroups among the five classes, the cente- narians have the common haplogroups M7b2 and B5b with the PD patients and common haplogroup B5b with the T2D patients. In addition, the 112 Japanese semi-supercentenarians (over 105 years old) recently reported were also examined by the method proposed. The results obtained were the haplogroups D4a, B4c1a, M7b2, F1, M1, and B5b. These results are different from the previously reported haplogroup classifications. As the proposed analysis method can predict a person's mtSNP constitution and the probabilities of becoming a centenarian, AD patient, PD patient, or T2D patient, it may be useful in initial diagnosis of various diseases. 展开更多
关键词 mtSNPs haplogroup semi-supercentenarians CENTENARIANS Alzheimer's disease Parkinson's disease type 2 diabetic patients healthy non-obese young males radial basis function (RBF)
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The genetic variation in Monocarboxylic acid transporter 2 (MCT2) has functional and clinical relevance with male infertility 被引量:2
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作者 Jinu Lee Dong Ryul Lee Suman Lee 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第5期694-697,I0007,共5页
Monocarboxylic acid transporter 2 (MCT2) transports pyruvate and lactate outside and inside of sperms, mainly as energy sources and plays roles in the regulation of spermatogenesis. We investigated the association a... Monocarboxylic acid transporter 2 (MCT2) transports pyruvate and lactate outside and inside of sperms, mainly as energy sources and plays roles in the regulation of spermatogenesis. We investigated the association among genetic variations in the MCT2 gene, male infertility and MCT2 expression levels in sperm. The functional and genetic significance of the intron 2 (+28201A 〉 G, rs10506398) and 3' untranslated region (UTR) single nucleotide polymorphism (SNP) (+2626G 〉 A, rs10506399) of MCT2 variants were investigated. Two MCT2 polymorphisms were associated with male infertility (n = 471, P 〈 0.05). In particular, the MCT2-3' UTR SNP (+2626 G 〉 A) had a strong association with the oligoasthenoteratozoospermia (OAT) group. The +2626GG type had an almost 2.4-fold higher sperm count than that of the +2626AA type (+2626GG; 66 x 106 vs +2626AA; 27 x 106, P 〈 0.0001). The MCT2-3' UTR SNP may be important for expression, as it is located at the MCT2 3' UTR. The average MCT2 protein amount in sperm of the +2626GG type was about two times higher than that of the +2626AA type. The results suggest that genetic variation in MCT2 has functional and clinical relevance with male infertility. 展开更多
关键词 3' UTR male infertility monocarboxylic acid transporter 2 single nucleotide polymorphism SPERM
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Molecular diagnosis of 5α-reductase-2 gene mutation in two Indian families with male pseudohermaphroditism 被引量:1
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作者 Marumudi Eunice Pascal Philibert +7 位作者 Bindu Kulshreshtha Francoise Audran Francoise Paris Madan L. Khurana Praveen E. Pulikkanath Kiran Kucheria Charles Sultan Ariachery C. Ammin 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第5期815-818,共4页
Aim: To identify the genotype of two Indians with male pseudohermaphroditism. Methods: Standard radioimmunoassay procedure was used for estimating hormonal levels. Conventional cytogenetic analysis was carded out fo... Aim: To identify the genotype of two Indians with male pseudohermaphroditism. Methods: Standard radioimmunoassay procedure was used for estimating hormonal levels. Conventional cytogenetic analysis was carded out for diagnosing the genetic sex in these subjects with genital ambiguity. Molecular analysis was carried out by standard polymerase chain reaction procedure using different sets of primers and reaction conditions specific for the 5α- reductase type 2 gene (SRDSA2) gene. Direct sequencing was carried out using the ABI Prism dye terminator sequencing kit and the ABI 310 sequencing apparatus. Results: We found an SRDSA2 gene mutation in exon 5, where arginine is substituted with glutamine (R246Q), in two males with pseudohermaphroditism and ambiguous genitalia from unrelated families. This is the first time this mutation has been reported in individuals from India. Conclusion: Identification of the R246Q mutation of the SRDSA2 gene from two unrelated Indian families possibly extends the founder gene effect. 展开更多
关键词 male pseudohermaphroditism 5αRD-2 deficiency DIHYDROTESTOSTERONE SRD5A2 gene mutation perineoscrotal hypospadias
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Ce-modified USY zeolite catalysts for catalytic oxidation of chlorinated VOCs:Effect of the location of CeO_(2) and its synergistic effect with USY zeolite 被引量:3
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作者 Xiaolin Guo Zhiming Li +3 位作者 Ang Zhou Yijun Shi Yong Wang Renxian Zhou 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第11期2068-2077,I0003,共11页
The catalytic behavior of a catalyst for chlorine-containing volatile organic compounds(CVOCs) oxidation largely depends on the synergistic interaction between the oxidizing and acidic sites.In the present work,two ca... The catalytic behavior of a catalyst for chlorine-containing volatile organic compounds(CVOCs) oxidation largely depends on the synergistic interaction between the oxidizing and acidic sites.In the present work,two catalysts with different distributions of CeO_(2) on the inner and outer surfaces of 4.0Ce-USY-ex and 4.0Ce-USY-dp(USY zeolite) were prepared respectively by ion exchange and deposition methods,with a purpose of finding out how the location of the oxidation sites(CeO_(2)) influence its synergistic effect with the acidic sites of zeolite.The results show that 4.0Ce-USY-ex is much more active for catalytic degradation of 1,2-dichloroethane(DCE),while 4.0Ce-USY-dp catalyst exhibit higher catalytic degradation activity for other structured CVOCs(dichloromethane(DCM),trichloroethylene(TCE),chlorobenzene(CB)).CeO_(2) in 4.0Ce-USY-ex catalyst mainly disperses in the pore channels of USY zeolite,and there are many strong acid centers on the surface,which is conducive to the dechlorination conversion of CVOCs.However,CeO_(2) in 4.0Ce-USY-dp catalyst is mainly distributed on the outer surface of USY and has strong oxidation ability,which contributes to the deep oxidation of CVOCs.Moreover,the presence of a large number of strong acid centers on the catalyst surface of 4.0Ce-USY-ex catalysts leads to severe accumulation of surface carbon species and significantly decreases its stability towards DCE.However,a large number of active oxygen species on the surface of 4.0Ce-USY-dp and CeO_(2) catalysts are beneficial to the deep oxidation of DCE,reducing the formation of surface carbon and thus improving the stability of the catalyst.Thus,the influence of the location of the oxidation sites on its synergistic effect with the acidic sites was established in the present work,which could provide some new ideas for the rational design of CVOCs degradation catalyst with appropriate distribution of active sites. 展开更多
关键词 CVOCs oxidation CeO_(2) USY location Synergistic effect Rare earths
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Regulation of fertilization in male rats by CatSper2 knockdown 被引量:3
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作者 Zhen Zhang Gen-Lin Wang +4 位作者 Hui-Xia Li Lian Li Qun-Wei Cui Cheng-Bin Wei Fei Zhou 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第2期301-309,共9页
Interest in ion channels as drug targets for contraception has grown with the realization that certain ion channel subunits are located exclusively in sperm. Selective knockdown of ion channel subunits can lead to inf... Interest in ion channels as drug targets for contraception has grown with the realization that certain ion channel subunits are located exclusively in sperm. Selective knockdown of ion channel subunits can lead to infertility without ill effects, and selective inhibitors and/ or openers of these ion channels could interfere with sperm function. In this study, in vivo electmporation (EP) and rete testis microinjection-mediated plasmid DNA were adopted to silence CatSper2 expression, which is essential in sperm hyperactivation. The results showed that high transfection efficiency and expression were achieved by plasmid DNA that was directly injected into the rete testis. As a result of the expression of CatSper2 being blocked, the treatment group showed significantly lower (P〈0.05) hyperactivation rate, fertilization rate in vitro, migration motility in viscoelastic solution and intracellular Ca2+ peak. The low hyperactivation and fertilization rates lasted for 60 days. Meanwhile, analysis of the sperm survival rate and testis histology indicated that in vivo EP had no significant effect on the function of the testis, spermatogenesis or sperm activity. The present study demonstrated that it was feasible to achieve male contraception by silencing the expression of CatSper2, the key protein involved in sperm hvoeractivation. 展开更多
关键词 Catsper2 in vivo electroporation male contraception rete testis microinjection
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Novel UBE2B-associated polymorphisms in an azoospermic / oligozoospermic population 被引量:2
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作者 Ivan Huang Benjamin R. Emery +3 位作者 Greg L. Christensen Jeanine Griffin C. Matthew Peterson Douglas T. Carrell 《Asian Journal of Andrology》 SCIE CAS CSCD 2008年第3期461-466,共6页
Aim: To assess whether abnormalities exist in the UBE2B gene in a population of infertile human males, and to establish biologic plausibility of any discovered mutations. Methods: We carried out polymerase chain rea... Aim: To assess whether abnormalities exist in the UBE2B gene in a population of infertile human males, and to establish biologic plausibility of any discovered mutations. Methods: We carried out polymerase chain reaction (PCR) amplification and sequence analysis of the 5'-untranslated region and six exons of the UBE2B gene, including flanking intronic regions, in a group of fertile and infertile men. Following the identification of a putative promoter region that contained single or dual triplet deletions within a 10-CGG repeat island, we evaluated the binding affinity of these identified polymorphisms as compared to the wild-type sequence to transcription factor SP1 using a DNA-protein gel shift assay. Results: There was a novel exonic single nucleotide polymorphism (SNP) noted in exon 4 in 5% of infertile men. In silico 3D modeling of the altered protein showed an innocuous isoleucine for valine substitution. There were no mutations noted within any of the other exons. Three novel intronic SNPs were identified within the fertile group, and seven novel intronic SNPs identified in the infertile group. The DNA-protein gel shift assay noted that both single CGG deletion and double CGG deletion bands had approximately twice the binding affinity compared to the wild-type for SP1. The negative control confirmed no non-specific protein binding. Conclusion- By themselves, a single or double CGG deletion is unlikely to pose biologic significance. However, such deletions in this suspected promoter region are associated with increased binding affinity for SP1, and might represent one of several factors required for alteration of UBE2B gene expression. 展开更多
关键词 UBE2B SP1 SPERMATOGENESIS male infertility single nucleotide polymorphism
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Expression of inducible nitric oxide synthase and cyclooxygenase-2 in pancreatic adenocarcinoma:Correlation with microvessel density 被引量:14
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作者 Hans U.Kasper Hella Wolf +2 位作者 Uta Drebber Helmut K.Wolf Michael A.Kern 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第13期1918-1922,共5页
AIM:Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins.Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide. Both have constitutive and inducible i... AIM:Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins.Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide. Both have constitutive and inducible isoforms.The inducible isoforms (iNOS and COX-2) are of great interest as regulators of tumor angiogenesis,tumorigenesis and inflammatory processes.This study was to clarify their role in pancreatic adenocarcinomas. METHODS:We investigated the immunohistochemical iNOS and COX-2 expression in 40 pancreatic ductal adenocardnomas of different grade and stage.The results were compared with microvessel density and dinicopathological data. RESULTS:Twenty-one (52.5%) of the cases showed iNOS expression,15 (37.5%) of the cases were positive for COX-2. The immunoreaction was heterogeneously distributed within the tumors.Staining intensity was different between the tumors.No correlation between iNOS and COX-2 expression was seen.There was no relationship with microvessel density. However,iNOS positive tumors developed more often distant metastases and the more malignant tumors showed a higher COX-2 expression.There was no correlation with other clinicopathological data. CONCLUSION:Approximately half of the cases expressed iNOS and COX-2.These two enzymes do not seem to be the key step in angiogenesis or carcinogenesis of pancreatic adenocarcinomas.Due to a low prevalence of COX-2 expression,chemoprevention of pancreatic carcinomas by COX-2 inhibitors can only achieve a limited success. 展开更多
关键词 Adenocarcinoma Aged Aged 80 and over Cyclooxygenase 2 Female Humans Immunohistochemistry ISOENZYMES Male Membrane Proteins MICROCIRCULATION Middle Aged Nitric Oxide Synthase Nitric Oxide Synthase Type II Pancreas Pancreatic Neoplasms Prostaglandin-Endoperoxide Synthases
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Effects of Warm Needling at Zusanli(ST 36)on NO and IL-2 Levels in the Middle-Aged and Old People 被引量:3
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作者 李苏 陈开阳 +3 位作者 吴英 焦健慧 陶立富 王友京 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2003年第2期127-128,共2页
42 middle-aged and old people at the age between 55-70 years were selected and given the warm needling at Zusanli (ST 36), and their IL-2 and NO contents of peripheral blood before and after acupuncture were determine... 42 middle-aged and old people at the age between 55-70 years were selected and given the warm needling at Zusanli (ST 36), and their IL-2 and NO contents of peripheral blood before and after acupuncture were determined. The results showed that IL-2 and NO contents increased significantly after the warm needling (P<0.01). 展开更多
关键词 Acupuncture Therapy Acupuncture Points Aged Female Humans Hypertension INTERLEUKIN-2 Male Middle Aged MOXIBUSTION Nitric Oxide Sleep Initiation and Maintenance Disorders
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体重指数正常的男性2型糖尿病患者合并非酒精性脂肪性肝病与骨代谢指标的相关性
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作者 张玲 崔仕健 张红军 《现代临床医学》 2025年第5期362-364,共3页
目的:分析体重指数(BMI)正常的男性2型糖尿病(T2DM)患者合并非酒精性脂肪性肝病(NAFLD)与骨代谢指标的相关性。方法:收集2022年1月至2023年1月在广元市第一人民医院住院的97例BMI正常的男性T2DM患者的临床资料,分为T2DM合并NAFLD组39例... 目的:分析体重指数(BMI)正常的男性2型糖尿病(T2DM)患者合并非酒精性脂肪性肝病(NAFLD)与骨代谢指标的相关性。方法:收集2022年1月至2023年1月在广元市第一人民医院住院的97例BMI正常的男性T2DM患者的临床资料,分为T2DM合并NAFLD组39例、T2DM无NAFLD组58例,比较两组骨代谢指标等临床资料。结果:T2DM合并NAFLD组患者的BMI、β-Ⅰ型胶原交联羧基端肽(β-CTX)、碱性磷酸酶(ALP)水平均高于T2DM无NAFLD组(P<0.05);logistic回归分析结果显示,BMI、ALP、β-CTX水平是T2DM患者合并NAFLD的影响因素(P<0.05)。结论:对于BMI正常的男性T2DM患者,仍需密切关注体重变化,定期复查ALP、β-CTX,预防NAFLD的发生。 展开更多
关键词 2型糖尿病 男性 非酒精性脂肪性肝病 骨代谢指标
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Correlation between sperm DNA 8-Hydroxy-2'-deoxyguanosine level and semen quality
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作者 Bing PANG Tai-Yi JIN +3 位作者 Xue-Zhi JIANG N G Viavian H M Shen C N Ong Shanghai Medical University,Shanghai 200032,China National University of Singapore,Singapore 119074,China 《Asian Journal of Andrology》 SCIE CAS CSCD 2001年第4期304-304,310,共2页
8-hydroxy-2’-deoxyguanosine (8-OHdG), a typical form ofDNA adducts, is a key molecular biomarker for DNA oxidativedamage. The aim of the present study was to evaluote the correla-tion between the sperm DNA 8-OHdG lev... 8-hydroxy-2’-deoxyguanosine (8-OHdG), a typical form ofDNA adducts, is a key molecular biomarker for DNA oxidativedamage. The aim of the present study was to evaluote the correla-tion between the sperm DNA 8-OHdG level and the semen quality.In 52 male infertile patients, the sperm DNA 8-OHdG level wasdetermined by a high performance liquid chromatograph with elec-trochemical detector and the semen quality was examined according 展开更多
关键词 8-hydroxy-2'-deoxyguanosine SPERM DNA semen quality male infertility
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A novel missense mutation in QRICH2 causes male infertility due to multiple morphological abnormalities of the sperm flagella
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作者 Yousaf Raza Huan Zhang +13 位作者 Muhammad Zubair Ansar Hussain Nisar Ahmad Min Chen Gang Yang Musavir Abbas Tanveer Abbas Muhammad Shoaib Ghulam Mustafa Imtiaz Ali Meftah Uddin Suixing Fan Wasim Shah Qinghua Shi 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第9期24-32,68,69,共11页
Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the ... Multiple morphological abnormalities of the sperm flagella(MMAF)are characterized by bent,irregular,short,coiled,and absent flagella.MMAF is caused by a variety of genes,some of which have been identified.However,the underlying genetic factors responsible for the majority of MMAF cases are still largely unknown.The glutamine-rich 2(QRICH2)gene plays an essential role in the development of sperm flagella by regulating the expression of essential sperm flagellar biogenesis-associated proteins,and genetic variants of QRICH2 have been identified as the primary cause of MMAF in humans and mice.Here,we recruited a Pakistani consanguineous family to identify the genetic variant causing infertility in patients with MMAF.Whole-exome sequencing and Sanger sequencing were conducted to identify potentially pathogenic variants causing MMAF in infertile patients.Hematoxylin and eosin(HE)staining was performed to analyze sperm morphology.Quantitative polymerase chain reaction,western blot,and immunofluorescence staining analyses were conducted to observe the expression of QRICH2 in spermatozoa.A novel homozygous missense variant(c.4618C>T)in QRICH2 was identified in the affected patients.Morphological analysis of spermatozoa revealed the MMAF phenotype in infertile patients.qPCR revealed a significant reduction in the level of sperm QRICH2 mRNA,and immunofluorescence staining revealed a lack of sperm QRICH2 expression.Additionally,patients harboring a homozygous QRICH2 mutation presented reduced expression of outer dense fiber 2(ODF2)in sperm,whereas sperm expression of A-kinase anchor protein 4(AKAP4)was normal.These findings expand our understanding of the genetic causes of MMAF-associated male infertility and emphasize the importance of genetic counseling. 展开更多
关键词 male infertility MMAF ASTHEnoZOOSPERMIA QRICH2 missense mutation
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Greedysearch based service location in P2P networks
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作者 Zhu Cheng Liu Zhong Zhang Weiming Yang Dongsheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期886-893,共8页
A model is built to analyze the performance of service location based on greedy search in P2P networks. Hops and relative QoS index of the node found in a service location process are used to evaluate the performance ... A model is built to analyze the performance of service location based on greedy search in P2P networks. Hops and relative QoS index of the node found in a service location process are used to evaluate the performance as well as the probability of locating the top 5% nodes with highest QoS level. Both model and simulation results show that, the performance of greedy search based service location improves significantly with the increase of the average degree of the network. It is found that, if changes of both overlay topology and QoS level of nodes can be ignored during a location process, greedy-search based service location has high probability of finding the nodes with relatively high QoS in small number of hops in a big overlay network. Model extension under arbitrary network degree distribution is also studied. 展开更多
关键词 greedy-search service location P2P network.
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