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21.
目的:观察PCR仪与测序仪在丙型肝炎病毒(HCV)基因型检测中的应用。方法:选择2018年1月~2018年12月收治的134例HCV感染患者为研究对象,给予患者PCR仪检测、测序仪检测。结果:测序仪检测134例均可分型,PCR仪检测130例患者可分型,4例未能分型。PCR检测结果:134例HCV感染患者中,1b型59例,2a型47例,3a型6例,3b型15例,6a型3例,4例为分出型别。基因测序结果:134例均可分型:1型59例,2a型40例,2i型7例,3a型6例,3b型15例,6a型3例,6n型4例。PCR仪检测法检测符合率97.0%。结论:PCR仪测序仪检测用于丙型肝炎病毒基因型检测,操作便捷,但其只能检测探针覆盖的型别,个别罕见型别不能分型。  相似文献   
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1. To investigate Genkwa Flos hepatotoxicity, a cell metabolomics strategy combined with serum pharmacology was performed on human HL-7702 liver cells in this study.

2. Firstly, cell viability and biochemical indicators were determined and the cell morphology was observed to confirm the cell injury and develop a cell hepatotoxicity model. Then, with the help of cell metabolomics based on UPLC-MS, the Genkwa Flos group samples were completely separated from the blank group samples in the score plots and seven upregulated as well as two down-regulated putative biomarkers in the loading plot were identified and confirmed. Besides, two signal molecules and four enzymes involved in biosynthesis pathway of lysophosphatidylcholine and the sphingosine kinase/sphingosine-1-phosphate pathway were determined to investigate the relationship between Genkwa Flos hepatotoxicity and these two classic pathways. Finally, the metabolic pathways related to specific biomarkers and two classic metabolic pathways were analyzed to explain the possible mechanism of Genkwa Flos hepatotoxicity.

3. Based on the results, lipid peroxidation and oxidative stress, phospholipase A2/lysophosphatidylcholine pathway, the disturbance of sphingosine-1-phosphate metabolic profile centered on sphingosine kinase/sphingosine-1-phosphate pathway and fatty acid metabolism might be critical participators in the progression of liver injury induced by Genkwa Flos.  相似文献   

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In low and middle-income countries mammographic breast cancer screening is prohibitively expensive and a cheaper alternative option is to use ultrasound as the primary screening test. In 2009, China launched a breast cancer screening programme for rural women aged 35–64 years with clinical breast examination coupled with ultrasound as the primary tool. Our study aimed to analyse the cost-effectiveness of breast screening compared to no screening among Chinese rural women. We developed a Markov model to estimate the lifetime costs and effects for rural women aged 35 years from a societal perspective. Asymptomatic women in the intervention arm were screened every 3 years before age 64 years. Breast cancer in the non-screening arm can only be diagnosed on presentation of symptoms. Parameter uncertainty was explored using one-way and probabilistic sensitivity analyses. Compared to no screening, breast cancer screening cost $186.7 more and led to a loss of 0.20 quality-adjusted life years (QALYs). Breast screening was more expensive and did harm to health among rural women with an incremental cost-effectiveness ratio (ICER) of $-916/QALY. The sensitivity analysis identified utility loss from false positives as the factor that most influenced the results, but this did not affect the conclusions. In a rural setting with such low breast cancer incidence, screening for asymptomatic disease is not cost-effective with current screening tools. Priority should be given to ensure that symptomatic women have proper access to diagnosis and treatment at an early stage as this will lead to mortality reductions without the usual screening harms.  相似文献   
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目的 基于基因组Survey分析对刺果甘草Glycyrrhiza pallidiflora Maxim.基因组大小和杂合率进行估计,并通过叶绿体基因组序列特征对其在甘草属Glycyrrhiza L.中的系统发育位置进行研究。方法 使用二代测序技术对刺果甘草进行测序,采用K-mer方法对测序reads进行分析,估算刺果甘草基因组大小和杂合率,使用生物信息学方法进行叶绿体基因组组装、注释和系统发育分析。结果 Survey分析结果显示其基因组大小约为577.82 Mb,杂合度约为0.31%,重复序列比例约为53.72%。叶绿体基因组长度为127,267 bp,不具有典型的四分体结构,总GC含量为34.32%,包含110个基因,其中76个蛋白质编码基因,30个tRNA基因和4个rRNA基因。系统发育分析表明,刺果甘草与圆果甘草G. squamulosa Franch.亲缘较接近。结论 刺果甘草存在低杂合和重复序列较多的特点,为了更好地对全基因组进行序列拼接和组装,可尝试采用三代测序结合二代测序的分析策略进行基因组组装;刺果甘草叶绿体全基因组比对和系统发育分析,为后续开展甘草属遗传多样性研究和分子鉴定标记筛选提供了重要依据。  相似文献   
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我国奶牛养殖规模不断扩大,奶业产值比重逐步提高,给奶牛疫病防治带来巨大压力。奶牛乳房炎及细菌性肺炎等呼吸系统疾病和细菌性肠炎等消化系统疾病最为常见,抗菌药物的使用成为主要防治手段。但抗菌药物的不当使用易使细菌产生耐药性,增加临床治疗的成本和难度,危害我国奶牛产业发展。本文对截至2021年7月我国和美国、英国、日本、欧盟批准用于奶牛的抗菌药物产品进行整理、统计与分析,包括抗菌药物的分类、剂型以及适应证等,旨在为我国奶牛用抗菌药物管理、合理用药和新兽药开发提供参考。  相似文献   
29.

Aim

Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is an immune inhibitory receptor which is expressed within most types of hematopoietic cells and negatively regulates immune responses. Recently, we found LAIR-1 expression to be present within tumors of nonhematopoietic lineages. However, the roles of LAIR-1 in hepatocellular carcinoma (HCC) have yet to be examined. The purpose of this study was to investigate the expression of LAIR-1 in HCC tissue and assess its clinical significance at this site.

Materials and methods

Expression levels of LAIR-1 within HCC samples collected from 90 patients and compared with that of slides of normal liver tissue collected from 9 non-HCC patients were measured by immunohistochemistry using tissue microarrays. A semiquantitative score was assigned, as was based on staining intensity and percent of positive cells and a Spearman Rank correlation test was used to assess any potential significant correlations between LAIR-1 expression and clinicopathological factors. Overall survival analysis was performed using the Kaplan-Meier and Log Rank statistical test.

Results

LAIR-1 expression was detected in cancer tissue and adjacent tumor tissue, but not in normal liver tissue. The percent of LAIR-1-positive expression in cancer tissue of HCC samples was 97.78% (88/90) while that in adjacent tumor tissue was 96.67% (87/90). Significantly greater expression levels of LAIR-1 were obtained from cancer tissue (Mean?±?SD?=?5.722?±?2.145) than that in adjacent tumor tissue (4.141?±?1.486). In addition, LAIR-1 expression was found to be significantly correlated with pathological grade of HCC, T stage, and age. Expression levels of LAIR-1 were related with worse overall survival rates of HCC patients, especially in HCC patients with hepatic cirrhosis.

Conclusion

Results of this study show that LAIR-1 is expressed in HCC tissues and that high levels of LAIR-1 expression are associated with the poor cancer differentiation. In addition, overexpression of LAIR-1 was significantly associated with worse overall survival in the patients with HCC. These data suggest that LAIR-1 may be an independent predictor for clinical outcomes in patients with HCC.  相似文献   
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