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991.
企业员工应激源的因素结构研究   总被引:8,自引:1,他引:8  
目的 :该研究旨在确立企业员工应激源的因素结构。方法 :经过对 394 6名被试的探索性因素分析 ,提出企业员工应激源的 9因素结构。结果 :因素分别命名为职业发展、住房问题、工作特征、社会环境、人际关系、经济收入、子女问题、组织气氛和夫妻关系。结论 :企业员工应激源的 9因素结构获得了验证性因素分析的支持。  相似文献   
992.
Marchevsky AM  Wick MR 《Human pathology》2004,35(10):1179-1188
Recent advances in molecular pathology and other technologies such as proteomics present pathologists with the challenge of integrating the new information generated with high-throughput methods with current diagnostic models based mostly on histopathology and clinicopathologic correlations. Parallel developments in the field of medical informatics and bioinformatics provide the technical and mathematical methods to approach these problems in a rational manner. However, it remains unclear whether pathologists or other medical specialists will become primarily responsible for the development and maintenance of these multivariate and multidisciplinary diagnostic and prognostic models that are hoped to provide more accurate, individualized patient-based information. Evidence-based medicine (EBM) and medical decision analysis (MDA) are relatively new disciplines that use quantitative methods to assess the value of information, differentiate fact from myth, and integrate so-called best evidence into multivariate models for the assessment of prognosis, response to therapy, selection of laboratory tests, and other complex problems that influence individual patient care. We review from an epistemological viewpoint the current approach to information in pathology and describe some of the concepts developed by the practitioners of EBM and MDA.  相似文献   
993.
The full-length infectious cDNA clone was constructed and sequenced from the strain DM of echovirus 9, which was recently isolated from a 6-week-old child at the clinical onset of type 1 diabetes. Parallel with the isolate DM, the full-length infectious cDNA clone of the prototype strain echovirus 9 Barty (Barty-INF), was constructed and sequenced. Genetic relationships of the sequenced echo 9 viruses to the other members of the human enterovirus type B species were studied by phylogenetic analyses. Comparison of capsid protein sequences showed that the isolate DM was closely related to both prototype strains: Hill and Barty-INF. The only exception was the inner capsid protein VP4 where serotype specificity was not evident and the isolate DM clustered with the strain Hill and the strain Barty-INF with echovirus 30 Bastianni. Likewise, the nonstructural protein coding region, P2P3, of isolate DM was more similar to strain Hill than to strain Barty-INF. However, like echovirus 9 Barty, the isolate DM contained the RGD-motif in the carboxy terminus of capsid protein VP1. By blocking experiments using an RGD-containing peptide and a polyclonal rabbit antiserum to the alpha(v)beta(3)-integrin, it was shown that this molecule works as a cellular receptor for isolate DM. By using primary human islets, it was shown that the isolate DM is capable of infecting insulin-producing beta-cells like the corresponding prototype strains did. However, only isolate DM was clearly cytolytic for beta-cells. The infectious clones that were made allow further investigations of the molecular features responsible for the diabetogenicity of the isolate DM.  相似文献   
994.
目的探讨影响幕上高血压脑出血(SICH)患者预后的相关因素,以指导临床治疗和评估预后。方法回顾性分析符合本研究纳入标准的幕上高血压脑出血324例完整病历。以一般资料、起病症状、入院查体、影像学资料、治疗方式、并发症等43项为自变量,以发病后1个月后功能独立性评定评分(functional independence measure,FIM)为因变量,建立多重线性回归模型,筛选出对预后有影响的因素,并比较各因素的影响大小。结果经统计学处理发现血肿体积、入院时收缩期血压、GCS评分、脑室是否积血、血肿体积扩大、是否并发肺部感染和应激性溃疡等7项对预后有显著性的影响。结论血肿体积、入院GCS评分和脑室是否积血对预后影响有重要意义,可作为SICH患者预后的关键性指标。  相似文献   
995.
从技术和方法的角度阐述了关节机能运动学的发展历程.首先介绍了基于经典力学的关节运动机能学;然后从视频跟踪、透视技术、核磁成像三个方面分析了计算机辅助关节机能分析方法,并进一步讨论了机器人技术在运动机能分析中的应用情况.最后,简要讨论了关节运动机能学未来的发展趋势.  相似文献   
996.
目的: 建立人晶状体上皮细胞蛋白质组研究体系,探讨双向电泳和质谱鉴定技术在人晶状体上皮细胞蛋白质组研究中的作用。 方法: 体外培养人晶状体上皮细胞株,用两种不同方法提取总蛋白,进行固相pH梯度(IPG)等电聚焦双向凝胶电泳,凝胶通过GS-800扫描仪(Bio-Rad)获取图像并使用PDQuest专业图像分析软件分析。在此基础之上,胰酶消化蛋白质斑点并进行质谱分析。 结果: 获得了重复性较好的人晶状体上皮细胞蛋白质组电泳图谱。晶状体蛋白质斑点在等电点pH值为4-7、相对分子质量为17-72 kD之间均有分布。其中高丰度蛋白点主要分布于分子量19-50 kD、PI 5-7范围内。2个蛋白点通过质谱分析和数据库的检索得到了初步的鉴定。 结论: 建立起了一个稳定的分析人晶状体上皮细胞蛋白质组学实验体系;为进一步研究人类晶状体在生理状态及白内障等病理条件下的改变提供了蛋白质组学的研究方法和途径。  相似文献   
997.
BackgroundVulvovaginal candidiasis (VVC) is one of the most common lower genital tract infections in women; this unpleasant and extremely embarrassing pathology is one of the main reasons for gynaecological consultation. In Gabon, the prevalence of VVC remains poorly described even though VVC is known to be the leading gynaecological condition in several countries. This retrospective cross-sectional study sought to assess the prevalence of VVC among symptomatic women in southeastern Gabon.MethodsClinical samples were collected from patients suspected to have VVC during a 2-year period (from January 2016 to December 2017). Gram staining of vaginal smears provided indications of vaginal flora and confirmed the presence of yeast. Sabouraud-chloramphenicol and chromID Candida media were used to isolate yeast, and species identification was performed using morphological tests and the Vitek 2 Compact automated system.ResultsFor the 873 patients included in this study, the prevalence of VVC was 28.52%. Eleven Candida species were identified, with greater representation of Candida albicans (82.73%) than of Non Calbicans candida (NCAC) (17.27%), which were distributed as follows: Candida famata (4.02%), Candida spp. (3.61%), Candida rugosa (3.21%), Candida lipolytica (1.61%), Candida parapsilosis (1.61%), Candida glabrata (1.21%), Candida tropicalis (0.80%), Candida krusei (0.40%), Candida dubliniensis (0.40%), and Candida sphaerica (0.40%).ConclusionThis study offers the first estimation of VVC among Gabonese women in childbearing age with the symptoms. It showed that VVC is very common in Gabon. Calbicans as the most commonly represented species.  相似文献   
998.
Cytological scrape material of the oral mucosa from 114 patients with epithelial dysplasia and with oral cancer was stained with the Feulgen-reaction and investigated with an image analyzer. The size and the integrated optical density of cell nuclei, and four chromatin texture features were measured. All tumor slides contained cell nuclei with DNA greater than 5c, 16% of the slides had cell nuclei with DNA greater than 8c. A total of 14.5% of the tumor patients showed significantly increased DNA values in nuclei distant from the tumor. Two smears with severe epithelial dysplasia showed nuclei with DNA greater than 5c both in the tumor material and far from the tumor. Texture analysis allowed discrimination between benign, dysplastic and malignant smears. No correlation was found between DNA content and tumor staging. Image cytometry was a reliable method for detecting tumor cells. Epithelial dysplasia in areas distant from the tumor is probably due to "field canceration" of the epithelium.  相似文献   
999.
The K+ channel in rat parotid gland acinar cells were investigated by ensemble current noise analysis in single isolated cells employing the giga-seal whole cell current recording mode. Sets of 20–40 identical de- and hyperpolarization voltage steps were applied and the resultant current records were processed by computer to obtain the mean and the variance of the current. The time-course of the mean current could be fitted by the sum of two exponentials, suggesting a 3-state model. The simplest plausible hypothesis is a model with one open and two closed states. Assuming this model, the relationship between the variance (2) and the mean current (I) could be fitted by the function 2/I=i–I/N. The estimated single channeli/V-relations were similar to those taken from single channel current recordings, and the size of the population of channels per cell (N) was 76±26 (n=12). The validity of the model was tested by a successful simulation of the time-course of the variance.  相似文献   
1000.
精液分析中精子密度室内质量控制方法研究   总被引:2,自引:0,他引:2  
目的建立一种可行的精液密度测定的质量控制方法.方法采用血细胞计数板和计算机辅助精液分析(CASA)两种方法,对所选取的与精子头部直径相近的质控珠进行高、中、低三种密度测定,分别于日内及日间测试12次.结果采用血细胞计数板方法测试高、中、低三种密度结果的日内变异系数分别为12.09%、8.86%、4.72%,日间变异系数分别为16.71%、10.65%、10.22%.CASA法日内变异系数分别为6.65%、5.93%、3.80%,日间变异系数分别为7.90%、6.84%、6.14%.结论质控珠可用于以上两种测试精子密度方法的室内质量控制,从而达到保证实验室测试精子密度质量的目的.  相似文献   
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