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81.

Introduction:

Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient.

Case and methods:

The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab).

Results:

Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip.

Conclusion:

The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events.  相似文献   
82.
Consumer distrust is only recently beginning to be perceived as an important e-commerce issue and, unlike online trust, the nature and role of distrust is much less established. This study examines the influence of two important consumer characteristics (ethical ideology and risk aversion) on consumer’s ethically-based distrust of online retailers. Also, the moderating role of consumer’s need for personal contact with sales staff is tested. Results from 409 online consumers confirm that both relativist-based ethical ideology and risk aversion are strongly and positively related to consumers’ distrust. Interestingly, our findings show that positive effects of relativism and risk aversion on consumer’s distrust are moderated by consumers’ need for personal interaction, which is more pronounced for those consumers with a high need for personal interaction with retail salespeople.  相似文献   
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简述陆地卫星多光谱扫描(MSS)影象的特点,着重介绍陆地卫星多光谱扫描影象适用于中、小比例尺的土地资源凋查  相似文献   
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Focusing on digital text messages containing information about students’ absences and sent to parents by schools, the paper investigates the way school absenteeism is produced within affective assemblages. The paper unfolds a theoretical and methodological approach of ‘going with’ the text messages, in entanglements of affective flows. The empirical engagements, produced together with multiple agents in two Swedish schools, show that within the assemblages of human and nonhuman bodies, the text messages can become ‘stirrers’ that evoke nervousness and anxiety, but also excitement and feelings of control that affect the production and conception of absenteeism. The affective flows of text messages thus travel in all directions, with and against notions of linearity. The conclusion emphasizes how the text messages, as affective materialities, are an inextricable part of the production of school absenteeism in multiple and sometimes unexpected ways.  相似文献   
89.
国际互联网的迅速发展,使应用软件的销售模式发生了翻天覆地的变化。企业可以不必购买先进昂贵的应用软件,只需通过ASP就可以在网上及时获得所需的应用软件以及相关的服务。因此,对ASP的定义、分类、市场培育以及前景作了详细分析,并对中国ASP市场的发展做出展望。  相似文献   
90.
分子伴侣与蛋白质折叠   总被引:2,自引:0,他引:2  
井明艳  孙建义 《科技通报》2004,20(5):407-411
新合成的多肽链必须先经折叠和装配后形成特定的三维结构才具有活性.在多肽链折叠过程中,往往会产生折叠异常蛋白,形成集聚体.分子伴侣可有效地调控多肽链的正确折叠,从而避免集聚体的形成.文章主要对分子伴侣的定义、作用、种类、特性等做一介绍。  相似文献   
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