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Identification of normalization factors for quantitative realtime RT-PCR analysis of gene expression in Pacific abalone Haliotis discus hannai 被引量:1
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作者 邱礽 孙铂光 +2 位作者 房沙沙 孙黎 刘晓 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第2期421-430,共10页
Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) is widely used in studies of gene expression. In most of these studies, housekeeping genes are used as internal references without val... Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) is widely used in studies of gene expression. In most of these studies, housekeeping genes are used as internal references without validation. To identify appropriate reference genes for qRT-PCR in Pacific abalone Haliotis discus hannai, we examined the transcription stability of six housekeeping genes in abalone tissues in the presence and absence of bacterial infection. For this purpose, abalone were infected with the bacterial pathogen Fibrio anguillarum for 12 h and 48 h. The mRNA levels of the housekeeping genes in five tissues (digestive glands, foot muscle, gill, hemocyte, and mantle) were determined by qRT-PCR. The PCR data was subsequently analyzed with the geNorm and NormFinder algorithms. The results show that in the absence of bacterial infection, elongation factor-l-alpha and beta-actin were the most stably expressed genes in all tissues, and thus are suitable as cross-tissue type normalization factors. However, we did not identify any universal reference genes post infection because the most stable genes varied between tissue types. Furthermore, for most tissues, the optimal reference genes identified by both algorithms at 12 h and 48 h post-infection differed. These results indicate that bacterial infection induced significant changes in the expression of abalone housekeeping genes in a manner that is dependent on tissue type and duration of infection. As a result, different normalization factors must be used for different tissues at different infection points. 展开更多
关键词 Haliotis discus hannai housekeeping gene normalization factor quantitative real time rt-pcr reference gene
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A semi-quantitative coal burst risk classification system 被引量:5
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作者 Onur Vardar Chengguo Zhang +1 位作者 Ismet Canbulat Bruce Hebblewhite 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第5期721-727,共7页
Safety is the highest priority in the mining industry as underground mining in particular poses high safety risks to its workers. In underground coal mines, coal bursts are one of the most catastrophic hazards, which ... Safety is the highest priority in the mining industry as underground mining in particular poses high safety risks to its workers. In underground coal mines, coal bursts are one of the most catastrophic hazards, which involves sudden and violent dynamic coal mass failure with rapid ejection of the broken material into the mine workings. Despite decades of research, the contributing mechanisms of coal bursts are still not completely understood. Hence, it remains challenging to forecast coal bursts and quantify their likelihood of occurrence. However, a range of geological and geotechnical factors are associated with coal bursts and can increase the coal burst proneness. This paper introduces a semi-quantitative coal burst risk classification system, namely, BurstRisk. Based on back-analysis of case histories from Australia, China and the United States, BurstRisk classifies the coal burst risk into three categories:low, medium and high risk. In addition, it allows mining engineers to modify the weighting of the selected factors based on specific conditions. The risk classification charts introduced are for both longwall retreat and development sections of long-wall mining operations. This paper also provides a set of risk management strategies and control measures for effective coal burst mitigation. 展开更多
关键词 UNDERGROUND COAL MINING COAL BURST ROCKBURST Risk management Safety semi-quantitATIVE
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A Semi-Quantitative Analysis of Essential Micronutrient in Folium Lycii Using Laser-Induced Breakdown Spectroscopy Technique 被引量:3
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作者 孙对兄 苏茂根 +2 位作者 董晨钟 张大成 马新文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第4期478-481,共4页
Abstract In this paper, the capabilities of laser-induced breakdown spectroscopy (LIBS) for rapid analysis to multi-component plant are illustrated using a 1064 nm laser focused onto the surface of folium lycii. Bas... Abstract In this paper, the capabilities of laser-induced breakdown spectroscopy (LIBS) for rapid analysis to multi-component plant are illustrated using a 1064 nm laser focused onto the surface of folium lycii. Based on homogeneous plasma assumption, nine of essential micronutrients in folium lycii are identified. Using Saha equation and Boltzmann plot method electron density and plasma temperature are obtained, and their relative concentration (Ca, Mg, A1, Si, Ti, Na, K, Li, and Sr) are obtained employing a semi-quantitative method. 展开更多
关键词 PLASMA LIBS folium lycii semi-quantitative analysis
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Detection of Survivin mRNA in nasopharyngeal carcinoma by real-time fluorescence quantitative RT-PCR 被引量:1
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作者 Shengmiao Fu Junhong Cai +5 位作者 Zhihua Tu Yutian Wang Liqun Deng Zhu Liang Zhenqun Lin Xuanju Gong 《The Chinese-German Journal of Clinical Oncology》 CAS 2008年第9期523-526,共4页
Objective: To establish the method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in nasopharyngeat carcinoma (NPC) tissues. Methods: The total RNA was extracted from N... Objective: To establish the method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in nasopharyngeat carcinoma (NPC) tissues. Methods: The total RNA was extracted from NPC cell line CNE-2 and tissues with Trizol and then been transcribed reversely to cDNA, a method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in NPC tissues had been established, in which chronic nasopharyn-gitis patients' nasopharynx tissues treated as control group. Results: The expression of Survivin mRNA all could be detected either in CNE-2 cells, NPC tissues or in chronic nasopharyngitis patients' nasopharynx tissues, and there was higher the expression level of Survivin mRNA in NPC tissues than which in chronic nasopharyngitis patients' nasopharynx tissues, the difference was significant (P 〈 0.01). The expression of Survivin mRNA could be detected both in stage Ⅰ + Ⅱ and stage Ⅲ + Ⅳ NPC, and there was no significant difference in relative quantifications of gene expression between these two groups (P 〉 0.05). There was no relationship between Survivin mRNA expression and age and sex of NPC patients (P 〉 0.05). Conclusion: Real time fluorescence quantitative RT-PCR is a rapid, effective and high sensitive method for detecting the expression of Survivin mRNA in NPC tissues. The overexpression of Survivin mRNA may play some roles in pathogenesis of NPC. 展开更多
关键词 nasopharyngeal carcinoma (NPC) real-time fluorescence quantitative rt-pcr gene expression apoptosisinhibitor Survivin
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Detection and clinical significance of multidrug resistance-1 mRNA in bone marrow cells in children with acute lymphoblastic leukemia by real-time fluorescence quantitative RT-PCR 被引量:1
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作者 Yuan Lu Runming Jin +3 位作者 Kun Yang Lirong Sun Yan Xia Xiuying Pang 《Journal of Nanjing Medical University》 2008年第3期153-158,共6页
Objective: Multidrug resistance(MDR) is one of the most important reasons for treatment failure and recurrence of acute leukemia. Its manifestations are different in children with acute lymphoblastic leukemia(ALL... Objective: Multidrug resistance(MDR) is one of the most important reasons for treatment failure and recurrence of acute leukemia. Its manifestations are different in children with acute lymphoblastic leukemia(ALL) which may be due to different detection methods. This study was to detect the expression of MDR1 mRNA in bone marrow cells of children with ALL by real-time fluorescence- quantitative reverse transcription polymerase-chain reaction(FQ-RT-PCR), and combine minimal residual desease(MRD) detection by flow cytometry(FCM) and to study their relationship with treatment response and prognosis of ALL. Methods:The MDR1 mRNA levels in bone marrow cells from 67 children with ALL[28 had newly diagnosed disease, 27 had achieved complete remission(CR), 12 recurrent] and 22 children without leukemia were detected by FQ-RT-PCR. MRD was detected by FCM. The patients were observed for 9-101 months, with a median of 64 months. Results:Standard curves of human MDR1 and GAPDH genes were constructed successfully. MDR1 mRNA was detected in all children with a positive rate of 100%. The mRNA level of MDR1 was similar among the newly diagnosed ALL group, CR group, and control group(P 〉 0.05), but significantly higher in the recurrence group than that in newly diagnosed disease group and control group(0.50 ± 0.55 vs. 0.09 ± 0.26 and 0.12 ± 0.23, P〈 0.05). 54 ALL patients were followed up, and it was found that MDR1 mRNA level was significantly higher in ALL patients within 3 years duration than that of ALL patients with 3-6 years and over 6 years duration(0.63 ± 0.56 vs. 0.11 ± 0.12 and 0.04 ± 0.06, P〈 0.01). For the 28 children with newly diagnosed disease, the MDR1 mRNA level was similar between WBC 〉 50 ~ 109 group and WBC〈50 × 10^9 group(P〉 0.05). In the 33 CR patients, the MDR1 mRNA level was significantly higher in MRD〉10a group than that in MRD〈10a group(0.39 ± 0.47 vs. 0.03 ± 0.03, P 〈 0.05). Conclusion:The sensitivity and specificity of FQ-RT-PCR in detecting MDR1 mRNA in bone marrowy cells of children with ALL patients are high. MDR1 mRNA is expressed in children with and without leukemia. MDR1 mRNA is highly expressed in the CR ALL patients with high MRD, recurrence and short duration(within 3 years). Monitoring MRD and the MDR1 mRNA level might be helpful for individual treatment. 展开更多
关键词 LEUKEMIA CHILDREN multidrug resistance MDR1 gene minimal residual disease real-time fluorescence quantitative rt-pcr
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Synchronous Detection of DNA/RNA of Four Shrimp Viruses by Real-time Fluorescence Quantitative RT-PCR 被引量:1
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作者 Biao SHEN Zhongfa WANG +1 位作者 Xingjuan HU Songye GU 《Agricultural Biotechnology》 CAS 2014年第5期48-50,共3页
[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel rea... [ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel real-time fluorescence quantitative RT-PCR assay was established and optimized for simultaneously detecting DNA/RNA of four shrimp viruses (WSSV, IHHNV, TSV and YHV ). [ Result] The optimized real-time fluorescence quantitative RT-PCR system gener- ated typical amplification curves with high amplification efficiencies (E = 1.06, 1.07, 0.92 and 0.92, respectively), good hnear relationship ( r = 1 ), uniform repeatability ( standard deviation = 0.05 - 0.46 ; variation coefficient = 0.26% - 1.62% ) and high sensitivity, exhibiting no significant differences compared with re- al-time fluorescence quantitative PCR (average error of Ct value = 0.04 -0.40; T = 0.53 -2.50; P 〉 0.05 ). The total detection time was about 1 h. [ Conclusion] The optimized real-time fluorescence quantitative RT-PCR system can be used for rapid detection of WSSV, IHHNV, TSV and YHV. 展开更多
关键词 Real-time fluorescence quantitative rt-pcr Shrimp viruses Synchronous amplification of DNA/RNA
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Can semi-quantitative evaluation of uncertain (type II) time-intensity curves improve diagnosis in breast DCE-MRI? 被引量:1
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作者 Roberta Fusco Salvatore Filice +9 位作者 Vincenza Granata Ylenia Mandato Annamaria Porto Massimiliano D’Aiuto Massimo Rinaldo Maurizio Di Bonito Mario Sansone Carlo Sansone Antonio Rotondo Antonella Petrillo Petrillo 《Journal of Biomedical Science and Engineering》 2013年第3期418-425,共8页
Objective/Background: Qualitative assessment of uncertain (type II) time-intensity curves (TICs) in breast DCE-MRI is problematic and operator dependent. The aim of this work is to evaluate if a semi-quantitative asse... Objective/Background: Qualitative assessment of uncertain (type II) time-intensity curves (TICs) in breast DCE-MRI is problematic and operator dependent. The aim of this work is to evaluate if a semi-quantitative assessment of uncertain TICs could improve overall diagnostic performance. Methods: In this study 49 lesions from 44 patients were retrospectively analysed. Per each lesion one region-of-interest (ROI)- averaged TIC was qualitatively evaluated by two radiologists in consensus: all the ROIs resulted in type II (uncertain) TIC. The same TICs were semi-quantitatively re-classified on the basis of the difference between the signal intensities of the last-time-point and of the peak: this difference was classified according to two different cut-off ranges (±5% and ±3%). All patients were cytological or histological biopsy proven. Fisher test and McNemar test were performed to evaluate if results were statistically significant (p < 0.05). Results: Using ±5% cut-off 16 TICs were reclassified as type III and 12 as type I while 21 were reclassified again as type II. Using ±3% 22 TICs were reclassified as type III and 16 as type I while 11 were reclassified again as type II. The semi-quantitative classification was compared to the histological-cytological results: the sensitivity, specificity, positive and negative predictive values obtained with ±3% were 77%, 91%, 91% and 78% respectively while using ±5% were 58%, 96%, 94% and 68% respectively. Using the ±5% cut-off 26/28 (93%) TICs were correctly reclassified while using the ±3% cut-off 34/38 (90%) TICs were correctly reclassified (p < 0.05). Conclusions: Semi-quantitative methods in kinetic curve assessment on DCE-MRI could improve classification of qualitatively uncertain TICs, leading to a more accurate classification of suspicious breast lesions. 展开更多
关键词 BREAST Cancer Dynamic CONTRAST Enhanced-MRI Time Intensity CURVE TRACER Kinetics semi-quantitATIVE Analysis
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TaqMan real-time fluorescent quantitative RT-PCR in detection of macrophage inflammatory protein-2γ mRNA in myocarditis murine
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作者 杨佳荟 沈茜 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第5期301-304,共4页
Objective: To study the role of macrophage inflammatory protein (MIP)-2γ in myocarditis pathogenesis in BALB/c mice. Methods: The relationship between the progression of Coxsarckie virus B3(CVB3) viral myocarditis an... Objective: To study the role of macrophage inflammatory protein (MIP)-2γ in myocarditis pathogenesis in BALB/c mice. Methods: The relationship between the progression of Coxsarckie virus B3(CVB3) viral myocarditis and experimental autoimmune myocarditis and MIP-2γ mRNA expression in mouse was studied by TaqMan real-time fluorescent quantitative RT-PCR. Results: MIP-2γ mRNA expression rose on 3 to 5 d after CVB3 infection, reached peak on 7 d, and returned to normal level until 14 d, which corresponded well with the disease course. The MIP-2γ mRNA expression level rose significantly on the day 18 d after immunization with porcine cardiac myosin, which was consistent with pathological examination. Conclusion: MIP-2γ may be involved in the pathogenesis of myocarditis. 展开更多
关键词 TAQMAN real-time fluorescent quantitative rt-pcr MYOCARDITIS MIP-2γ MRNA
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THE DETECTION OF MDR1 GENE EXPRESSION USING FLUOROGENIC PROBE QUANTITATIVE RT-PCR METHOD
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作者 高劲松 马刚 +3 位作者 仝明 陈佩毅 王传华 何蕴韶 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2001年第2期96-100,共5页
Objective: To establish a fluoregenic probe quantitative RT-PCR (FQ-RT-PCR) method for detection of the expression of MDR1 gene in tumor cells and to investigate the expression of MDR1 gene in patients with lung cance... Objective: To establish a fluoregenic probe quantitative RT-PCR (FQ-RT-PCR) method for detection of the expression of MDR1 gene in tumor cells and to investigate the expression of MDR1 gene in patients with lung cancer. Methods: The fluorogenic quantitative RT-PCR method for detection of the expression of MDR1 gene was established. K562/ADM and K562 cell lines or 45 tumor tissues from patients with lung cancer were examined on PE Applied Biosystems 7700 Sequence Detection machine. Results: the average levels of MDR1 gene expression in K562/ADM cells and K562 cells were (6.86±0.65)× 107 copies/μg RNA and (8.49±0.67)×105 copies/μg RNA, respectively. The former was 80.8 times greater than the latter. Each sample was measured 10 times and the coefficient variation (CV) was 9.5% and 7.9%, respectively. Various levels of MDR1 gene expression were detected in 12 of 45 patients with lung cancer. Conclusion: Quantitative detection of MDR1 gene expression in tumor cells was achieved by using FQ-RT-PCR. FQ-RT-PCR is an accurate, and sensitive method and easy to perform. Using this method, low levels of MDR1 gene expression could be detected in 24% of the patients with lung cancer. 展开更多
关键词 Fluorogenic quantitative rt-pcr/MDR1 Expression/Real time DETECTION
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A quantitative RT-PCR assay for rapid detection of Eurasianlineage H10 subtype influenza A virus
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作者 Hailiang Sun Jian-Li Xue +7 位作者 Elizabeth Bailey Yifei Xu Guoliang Hu John Baroch Yi Zhang Lanny Pace Thomas J DeLiberto Xiu-Feng Wan 《Virologica Sinica》 SCIE CAS CSCD 2016年第5期444-447,共4页
Dear Editor,Influenza A viruses(IAVs)are single-stranded,negative sense RNA viruses.IAV subtype is determined on the basis of the viral surface glycoproteins,hemagglutinin(HA),and neuraminidase(NA).To date,18 HA and 1... Dear Editor,Influenza A viruses(IAVs)are single-stranded,negative sense RNA viruses.IAV subtype is determined on the basis of the viral surface glycoproteins,hemagglutinin(HA),and neuraminidase(NA).To date,18 HA and 11NA subtypes have been reported(Tong et al.,2012). 展开更多
关键词 PCR A quantitative rt-pcr assay for rapid detection of Eurasianlineage H10 subtype influenza A virus RT
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Analysis of photo inactivation damaged nucleic acid of VSV by means of quantitative RT-PCR
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《中国输血杂志》 CAS CSCD 2001年第S1期349-,共1页
关键词 Analysis of photo inactivation damaged nucleic acid of VSV by means of quantitative rt-pcr VSV ACID RT
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Establishment of Fluorescence Quantitative RT-PCR Assay for Detection of Equine Arteritis Virus
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作者 Wang Keke Liang Xinxin +7 位作者 Jiang Gangqiang Long Zhixin Hudusi Aierken Liu Zhiling Wang Yan Wu Xiaowei Xiao Yuanyuan Bai Meihua 《Animal Husbandry and Feed Science》 CAS 2024年第1期21-25,共5页
[Objective]The paper was to establish a fluorescence quantitative RT-PCR method for detection of equine arteritis virus(EAV).[Method]Primers and probes were developed for the EAV ORF7 gene sequence,and the reaction sy... [Objective]The paper was to establish a fluorescence quantitative RT-PCR method for detection of equine arteritis virus(EAV).[Method]Primers and probes were developed for the EAV ORF7 gene sequence,and the reaction system was optimized.Standard curves were established,leading to the initial development of the EAV fluorescence quantitative RT-PCR assay.The accuracy,specificity,and sensitivity of this method were subsequently evaluated.[Result]The EAV fluorescence quantitative RT-PCR assay demonstrated optimal performance at an annealing temperature of 61 C,with a final concentration of primer and probe set at 0.6μmol/L.The plasmid standard demonstrated a strong linear correlation with Ct values within the range of 1.6×10^(7)-1.6×10^(2)copies/μL.The equation of the standard curve was determined to be y=-2.68x+32.88,with an R^(2) value of 0.9927.Consequently,the EAV fluorescence quantitative RT-PCR assay was successfully established.The methodology employed was effective in detecting EAV,Theileria equi,equine herpesvirus-1(EHV-1),equine herpesvirus-4(EHV-4),and equine influenza virus(EIV).The findings indicated that the method was specifically capable of detecting EAV,while the other pathogens tested yielded negative results.The method demonstrated a high degree of specificity.It was employed to detect the standard plasmid cRNA synthesized through in vitro transcription following a 10-fold dilution.The results indicated that the minimum detection limit of the method was 1.6×10^(2) copies/μL,and it exhibited high sensitivity.The coefficient of variation,both within and between groups,was maintained at 1.8%,indicating good reproducibility.In this study,the fluorescence quantitative RT-PCR assay developed was utilized alongside the EAV fluorescence quantitative RT-PCR assay established by previous researchers to analyze a total of 234 clinical samples.Both methods yielded a positive detection rate of 14.1%,and the coincidence rate between the two techniques was found to be 100%.[Conclusion]The fluorescence quantitative RT-PCR assay developed in this study offers a novel approach and concept for the prevention and control of equine viral arteritis(EVA). 展开更多
关键词 Equine arteritis virus(EAV) ORF7 gene Fluorescence quantitative rt-pcr
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Research on Fast Semi-Quantitative Risk Assessment Method for High Temperature and High Pressure Gas Wells
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作者 Mifeng Zhao Hailong Geng +2 位作者 Jingcheng Zhang Junfeng Xie Kelin Wang 《World Journal of Engineering and Technology》 2021年第1期100-108,共9页
Aiming at the problem that the existing risk assessment methods in China cannot simply and accurately assess the safety risk of gas wells, a rapid semi-quantitative risk assessment method for gas wells under high temp... Aiming at the problem that the existing risk assessment methods in China cannot simply and accurately assess the safety risk of gas wells, a rapid semi-quantitative risk assessment method for gas wells under high temperature and pressure is studied. Based on the rapid risk assessment method of annulus well with pressure in Chevron Company and the existing risk assessment methods, the well barrier and annulus pressure of high temperature and high pressure gas wells are fully considered. A rapid semi-quantitative risk assessment method for high temperature and high pressure gas wells is established, which takes the annulus pressure value, well service life, annulus pressure recovery after pressure relief, reservoir conditions (formation pressure, production) and well CO<sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2 </span></sub><span style="font-family:Verdana;">and H</span><sub style="font-family:" white-space:normal;"=""><span style="font-size:12px;font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">S content as the key risk indexes. The method is applied in a gas field, and the risk value and risk grade of a practical well are semi-quantitatively evaluated. The overall risk situation of the well is obtained. The research results provide important technical guidance for the safe production of gas well.</span> 展开更多
关键词 HPHT semi-quantitATIVE Risk Assessment quantitative Scoring
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Semi-Quantitative Estimation of Ce<sup>3+</sup>/Ce<sup>4+</sup>Ratio in YAG:Ce<sup>3+</sup>Phosphor under Different Sintering Atmosphere
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作者 Lianming Wang Liqiang Zhuang +2 位作者 Hao Xin Yuexia Huang Deqiang Wang 《Open Journal of Inorganic Chemistry》 2015年第1期12-18,共7页
In order to confirm the relationship between the luminescence and the ratio of Ce3+/Ce4+ more clearly, a series of YAG:Ce3+ (Yttrium Aluminum Garnet, Y2.94Al5O12:0.06Ce3+) phosphors were pre- pared under different sin... In order to confirm the relationship between the luminescence and the ratio of Ce3+/Ce4+ more clearly, a series of YAG:Ce3+ (Yttrium Aluminum Garnet, Y2.94Al5O12:0.06Ce3+) phosphors were pre- pared under different sintering atmosphere. A semi-quantitative analysis based on X-ray photoe-lectron spectroscopy (XPS) was introduced to study the mole ratio of Ce3+/Ce4+ in the as-synthesized YAG:Ce3+ phosphors. The results indicated that the percentage of Ce3+/(Ce3+ + Ce4+) reached 88.46% under the reduction atmosphere. The emission intensity of YAG:Ce3+ phosphors was in-creased significantly with the increasing of Ce3+ concentration. 展开更多
关键词 YAG:Ce3+ PHOSPHOR semi-quantitATIVE ESTIMATION Luminescence RATIO of Ce3+/Ce4+ XPS Reduction Atmosphere
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Fault diagnosis of AMT gear shifting process based on semi-quantitative SDG model
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作者 LIU Hai-ou MENG Dong-mei PENG Jian-xin 《Journal of Beijing Institute of Technology》 EI CAS 2016年第3期316-322,共7页
In order to diagnose gear shifting process in automated manual transmission(AMT),a semi-quantitative signed directed graph(SDG)model is applied.Mathematical models are built by analysis of the power train dynamic ... In order to diagnose gear shifting process in automated manual transmission(AMT),a semi-quantitative signed directed graph(SDG)model is applied.Mathematical models are built by analysis of the power train dynamic and the gear shifting control process.The SDG model is built based on related priori knowledge.By calculating the fuzzy membership degree of each compatible passway and its possible fault source,we get the possibilities of failure for each possible fault source.We begin with the nodes with the maximum possibility of failure in order to find the failed part.The diagnosis example shows that it is feasible to use the semi-quantitative SDG model for fault diagnosis of the gear shifting process in AMT. 展开更多
关键词 semi-quantitative signed directed graph(SDG) fault diagnosis gear shifting process automated manual transmission (AMT)
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Hematization of Quartz Grains: Study of the Surface of Quartz Grains (M.E.B) and Semi-Quantitative Mineralization
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作者 Chia Marie Reine Kokoa Touvalé Marcel Kesse +2 位作者 Fory Yao Paul Assale Sougo Aoua Coulibaly Kouadio Affian 《Journal of Geoscience and Environment Protection》 2023年第11期82-90,共9页
Interest in the Côte d’Ivoire sedimentary basin has led to numerous investigations. All these investigations are aimed at understanding the functioning of the basin and a paleogeographic approach including sedim... Interest in the Côte d’Ivoire sedimentary basin has led to numerous investigations. All these investigations are aimed at understanding the functioning of the basin and a paleogeographic approach including sediment transport dynamics. However, the use of exoscopy and semi-quantitative mineralogy has been little developed. This study was carried out to compensate for this lack of interest in these methods. Its aim is to understand the transformation of quartz into hematite using exoscopy and semi-quantitative mineralogy in the Adiaké locality, in the eastern onshore basin of Côte d’Ivoire. Two methods were applied to 250 μm-diameter quartz grains from the 40 m coasts. Exoscopy provides information on microscopic texture, surface and corrosion, as well as determining the transport mechanism and deposition phases of quartz grains. Semi-quantitative mineralogy provides an estimate of the weight percentages of major element oxides and the ultrastructure of quartz grains. Exoscopy showed that these grains had been subjected to torrential fluvial transport. They were marked by mechanical and chemical traces during this transport and evolved in different environments. Semi-quantitative mineralogy shows the existence of negative and positive correlations between oxides. Negative correlations indicate a substitution, in order of importance, of silicon by iron, phosphorus and aluminum in these quartz. Positive correlations show that there is no substitution between the oxides concerned in these quartz grains. Divo’s quartz grains have recorded several mechanical and chemical microstructures of their sedimentary episodes, with the appearance of iron nodules in the ports left by silica. 展开更多
关键词 QUARTZ Exoscopy semi-quantitative Mineralogy Adiaké Ivory Coast
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Standardized Semi-Quantitative Evaluation of [123I]FP-CIT SPECT in a Multicenter Study
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作者 Andrea Skanjeti Giancarlo Castellano +10 位作者 Baldassarre Elia Francesca Dazzara Michela Zotta Gabriela Mariam Delgado Yabar Matteo Manfredi Marco Iudicello Maurizio Zibetti Patrizia Ferrero Paola Filippi Riccardo Emanuele Pellerito Valerio Podio 《Advances in Molecular Imaging》 2013年第4期55-60,共6页
To the best of our knowledge no multicenter studies have been published using standardized semi-quantitative evaluation of [123I]FP-CIT scan (DAT-SPECT). The aims of this study were: 1) to cross-compare semi-quantitat... To the best of our knowledge no multicenter studies have been published using standardized semi-quantitative evaluation of [123I]FP-CIT scan (DAT-SPECT). The aims of this study were: 1) to cross-compare semi-quantitative software-assisted evaluations of DAT-SPECTs performed in three centers with different equipments;2) to assess the accuracy of semi-quantitative evaluations of DAT-SPECT and 3) to identify the threshold with the best accuracy, sensitivity and specificity in a patient population with suspected parkinsonian syndrome. Materials and Methods: Two hundred twenty patients (mean age at the time of SPECT acquisition, 67.4 ± 9.5 yy) acquired in three centers (Ospedale San Luigi Gonzaga;Ospedale San Giovanni Battista Molinette;Ospedale Mauriziano Umberto I) were included. All of them underwent DAT-SPECT from January 2006 to July 2010. All exams were analyzed with the freely available software BASGAN and semi-quantitative data were used to predict disease. In particular, analyses were based on the values from the most deteriorated putamen and caudate, normalized for age and corrected for equipment. ROC analysis was performed and area under the curve (AUC) was estimated. Results: Analysis showed high AUCs (0.898, 0.864, 0.900 and 0.891 for each center and for the multicenter setting, respectively) confirming the very good accuracies reached. The best cut-off were 0.72 and 0.82 for putamen and caudate respectively. These thresholds allowed sensitivities and specificities in each center and in the multicenter setting of 76% and 96%, 91% and 82%, 93% and 90%, 86% and 89% respectively. No significant differences were observed between sensibility and specificity in each center. Conclusion: A unique threshold useful for all centers with high and similar sensitivities and specificities is possible after correction for age and equipments. The high accuracy reached in this multicenter trial by the semi-quantitative analysis seems similar to accuracies from qualitative analysis in other multicenter studies. 展开更多
关键词 Movement DISORDER PARKINSON Disease [123I]FP-CIT-SPECT semi-quantitATIVE EVALUATION MULTICENTER Study
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MSKUS、轴关键因子SDF-1、CXCR4与膝骨性关节炎K~L分级相关性及诊断价值
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作者 王慧娟 孟香艳 杨鹏飞 《贵州医科大学学报》 2026年第1期113-118,126,共7页
目的探讨肌骨超声(MSKUS)、轴关键因子基质细胞衍生因子1(SDF-1)、趋化因子受体4(CXCR4)与膝骨性关节炎(KOA)K~L分级相关性及诊断价值。方法选取2021年6月—2023年6月秦皇岛市海港医院收治的103例KOA患者作为研究组,另纳入同期103例健... 目的探讨肌骨超声(MSKUS)、轴关键因子基质细胞衍生因子1(SDF-1)、趋化因子受体4(CXCR4)与膝骨性关节炎(KOA)K~L分级相关性及诊断价值。方法选取2021年6月—2023年6月秦皇岛市海港医院收治的103例KOA患者作为研究组,另纳入同期103例健康体检者作为对照组;比较2组间MSKUS半定量评分、轴关键因子SDF-1、CXCR4水平差异,Spearman分析KOA患者K~L分级与MSKUS半定量评分、轴关键因子SDF-1、CXCR4的相关性,绘制受试者工作特征曲线(ROC)、求曲线下面积(AUC)及用校准曲线分析各指标单一及联合诊断效能。结果研究组MSKUS半定量总分、SDF-1、CXCR4水平高于对照组,且K~L分级中Ⅲ+Ⅳ级患者高于Ⅰ+Ⅱ级患者(P<0.05);KOA患者K~L分级与MSKUS半定量总分、轴关键因子SDF-1、CXCR4呈正相关(r=0.803、0.804、0.730,P<0.05);ROC曲线显示,MSKUS半定量总分、轴关键因子SDF-1、CXCR4单一诊断KOA的AUC分别为0.825(95%CI:0.767~0.875)、0.709(95%CI:0.642~0.770)、0.798(95%CI:0.737~0.851);MSKUS半定量总分、轴关键因子SDF-1、CXCR4联合诊断KOA的敏感度、特异性及准确度均高于单一诊断价值(P<0.05);校准曲线显示,联合诊断KOA的发生率与实际发生率基本一致,两条曲线贴合度较高。结论KOA患者MSKUS半定量总分及轴关键因子SDF-1、CXCR4表达与其K~L分级呈正相关,联合检测可显著提高KOA诊断效能。 展开更多
关键词 膝骨性关节炎 肌骨超声 半定量评分 基质细胞衍生因子1 趋化因子受体4
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刺五加皂苷合成关键酶基因表达的半定量RT-PCR分析 被引量:17
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作者 邢朝斌 龙月红 +3 位作者 吴鹏 何闪 梁能松 李宝财 《基因组学与应用生物学》 CAS CSCD 北大核心 2011年第6期691-696,共6页
根据已克隆的刺五加鲨烯合酶(squalene synthase,SS)、鲨烯环氧酶(squalene epoxidase,SE)和β-香树酯醇合成酶(β-amyrin synthase,bAS)基因序列信息设计引物,通过半定量RT-PCR分析了SS、SE和bAS基因在刺五加不同生长发育时期和不同器... 根据已克隆的刺五加鲨烯合酶(squalene synthase,SS)、鲨烯环氧酶(squalene epoxidase,SE)和β-香树酯醇合成酶(β-amyrin synthase,bAS)基因序列信息设计引物,通过半定量RT-PCR分析了SS、SE和bAS基因在刺五加不同生长发育时期和不同器官中表达量的变化。结果表明,SS、SE和bAS基因在各生长发育时期和各器官中均有表达,但表达量差异显著(P<0.05),三者均在盛花期表达量最高,之后降低,进入果实成熟期后SS和bAS的表达量迅速回升,SE无显著变化。SS和bAS在叶片和根中的表达量较高,SE表达量的最大值出现在叶片和幼茎中。刺五加SS、SE和bAS基因的表达间存在显著的正相关关系(P<0.05)。研究结果为进一步分析关键酶基因对刺五加三萜皂苷生物合成的影响奠定了基础。 展开更多
关键词 关键酶基因 表达 半定量RT—PCR
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聚丙烯酰胺凝胶银染技术在半定量RT-PCR中的应用 被引量:12
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作者 边杉 王颖 +4 位作者 于涛 丁选胜 吴梧桐 叶波平 奚涛 《中国药科大学学报》 CAS CSCD 北大核心 2004年第2期178-182,共5页
目的 :探讨聚丙烯酰胺凝胶银染技术在半定量RT PCR中的应用。方法 :提取正常组大鼠和链脲佐菌素致糖尿病模型组大鼠心肌组织总RNA ,逆转录得到cDNA第一链 ,以此为模板进行PCR扩增 ,利用聚丙烯酰胺凝胶电泳和DNA银染技术分析不同循环数... 目的 :探讨聚丙烯酰胺凝胶银染技术在半定量RT PCR中的应用。方法 :提取正常组大鼠和链脲佐菌素致糖尿病模型组大鼠心肌组织总RNA ,逆转录得到cDNA第一链 ,以此为模板进行PCR扩增 ,利用聚丙烯酰胺凝胶电泳和DNA银染技术分析不同循环数及模板量与PCR产物量间的关系。结果 :PCR扩增反应在第 2 0~ 2 5个循环 ,起始模板量为 0 8~ 2 4 μg时 ,PCR产物量与起始模板量呈现较好的线性关系。 结论 :通过控制起始模板量 ,减少PCR循环数使目的基因的扩增处于PCR扩增指数期 ,利用聚丙烯酰胺凝胶电泳和DNA银染技术 。 展开更多
关键词 聚丙烯酰胺凝胶电泳 DNA银染 半定量rt-pcr
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