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61.
The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone.  相似文献   
62.
Autoimmune thrombocytopenic purpura (AITP) is a bleeding disease in which autoantibodies are directed against the individual's own platelets, resulting in enhanced Fc-mediated platelet destruction by macrophages in the reticuloendothelial system. Most research in AITP has focused on characterization of the autoantibodies, while little has been devoted to the cellular immune mechanisms leading to autoantibody production. This report summarizes the current state of the literature and argues that enhanced T helper cell/antigen-presenting cell interactions in patients with AITP are the primary stimulus for the development of antiplatelet autoantibody production. Understanding these events is important for eventually identifying disease-initiating platelet autoantigens and ultimately developing specific immunotherapies for AITP.  相似文献   
63.
64.
Ruan  Sanbao  Fuller  Greg  Levin  Victor  Bruner  Janet M.  Zhang  Wei 《Journal of neuro-oncology》1998,37(3):223-228
The p21WAF1/Cip1 (p21) protein, a negative regulator of G1 checkpoint control, was overexpressed in the majority of human gliomas. To investigate whether p21 expression in brain metastases from various systemic origins is similar to that in gliomas and whether p21 expression is regulated differently in brain metastases and in corresponding primary tumors, we used immunohistochemical staining to examine the expression of p21 in paraffin-embedded sections prepared from primary colon and breast carcinomas and from metastatic brain tumors that originated from colon, breast, lung, and kidney cancers and from melanoma. Our results showed that 56% (28 of 50) of the brain metastases samples have more than 1% p21-positive staining cells compared with 87% of primary gliomas reported previously. Among the samples analyzed, p21 expression in brain metastases from breast carcinomas was much higher than in primary breast carcinomas. In contrast, p21 expression in brain metastases from colon carcinomas was less than primary colon carcinomas. The results from this pilot study suggest that p21 expression is regulated differently in metastatic and primary tumors.  相似文献   
65.
为了评价异环磷酰胺,美斯纳,阿霉素和5-氟脲嘧啶联治疗复发转移性乳癌的疗效。对乳腺癌根治术后接受常规CMF辅助化疗和放疗后,在2a内出现复发转移的26例患者应用IMAF方案化疗。结果完全缓解4例,部分缓解12例,总有效率为61.5%。毒副反应主要为恶性心呕吐、骨髓抑制,脱发和镜下血尿。结果表明IMAF方案是治疗复发转移性乳腺癌疗效较好的方案。  相似文献   
66.
目的:观察孕期大鼠摄入不同剂量的氟之后,对子代鼠血液和骨氟浓度及软骨细胞和骨关节结构的影响,以探索通过妊娠期母体给氟预防乳牙龋齿的新途径。方法:给妊娠SD大鼠分别用N aF按1 m g/kg体重、10 m g/kg体重和50 m g/kg体重灌胃至分娩,并用0.9%N aC l灌胃作为对照组。结果:①实验组各组子鼠血清中的氟化物含量均较对照组高(P<0.01);并且与母鼠摄入的氟剂量呈正相关。②在中、高剂量组子鼠上肢骨骨氟的含量明显高于对照组。③在高剂量组子鼠的上肢骨切片中可见软骨细胞和关节结构的破坏。结论:①妊娠期母体摄入的氟化物可进入其子体体内。②当母鼠摄入的氟化物剂量过高时,可引起骨组织的毒性损害。  相似文献   
67.
大蒜素对大鼠心室肌细胞L-型钙通道的影响   总被引:9,自引:0,他引:9  
目的:探讨大蒜素对大鼠心室肌细胞L-型钙通道的作用.方法:用急性酶解法获得大鼠的单个心肌细胞,用标准的全细胞膜片钳技术记录钙通道电流.结果:5、50、250和500μmol/L大蒜素分别抑制钙电流4.4%、26.91%、38.06%、72.90%.250μmol/L大蒜素能使心肌细胞钙电流-电压曲线明显上移,峰电流密度从(7.17±0.65)pA/pF减少至(4.44±0.52)pA/pF(n=15,P<0.05),但激活电位、峰电位和翻转电位无明显改变(P>0.05).大蒜素能使钙电流失活曲线明显左移(P<0.05).大蒜素对钙电流激活曲线、失活再复活曲线和频率依赖性无明显影响(P>0.05).结论:大蒜素呈浓度依赖性地抑制心肌细胞L-型钙通道.  相似文献   
68.
Regional healthcare platforms collect clinical data from hospitals in specific areas for the purpose of healthcare management. It is a common requirement to reuse the data for clinical research. However, we have to face challenges like the inconsistence of terminology in electronic health records (EHR) and the complexities in data quality and data formats in regional healthcare platform. In this paper, we propose methodology and process on constructing large scale cohorts which forms the basis of causality and comparative effectiveness relationship in epidemiology. We firstly constructed a Chinese terminology knowledge graph to deal with the diversity of vocabularies on regional platform. Secondly, we built special disease case repositories (i.e., heart failure repository) that utilize the graph to search the related patients and to normalize the data. Based on the requirements of the clinical research which aimed to explore the effectiveness of taking statin on 180-days readmission in patients with heart failure, we built a large-scale retrospective cohort with 29647 cases of heart failure patients from the heart failure repository. After the propensity score matching, the study group (n=6346) and the control group (n=6346) with parallel clinical characteristics were acquired. Logistic regression analysis showed that taking statins had a negative correlation with 180-days readmission in heart failure patients. This paper presents the workflow and application example of big data mining based on regional EHR data.  相似文献   
69.
目的 分析Lnczc3h7a在结直肠癌细胞中的表达及其对结肠癌细胞增殖和迁移的影响,并探讨其潜在的作用机制.方法 选择6种结直肠癌细胞株SW620、SW480、HCT116、DLD-1、Caco-2、HT-29与正常结直肠上皮细胞株FHC,采用RT-PCR法检测Lnczc3h7a在结直肠癌细胞株及正常结直肠上皮细胞株中...  相似文献   
70.
目的 研究胆道闭锁患儿肝脏组织中MMP-2、TGF-β1的表达,探讨其与胆道闭锁患儿肝纤维化的关系.方法 利用免疫组化法(SP法)检测33例胆道闭锁患儿肝脏组织中MMP-2、TGF-β1蛋白的表达,通过图像分析技术进行定量研究.结果 胆道闭锁患儿肝组织中MMP-2、TGF-β1蛋白均有不同程度的表达,以肝细胞胞浆、胞膜表达最为明显.MMP-2、TGF-β1蛋白在肝组织中的阳性表达随肝纤维化程度的加重而增强,呈正相关(前者r=0.5063,P<0.05;后者r=0.6179,P<0.05).MMP-2、TGF-β1在胆道闭锁患儿肝组织中的表达强度明显高于对照组(P<0.01),MMP-2与TGF-β1的表达有高度相关性(r=0.9200,P<0.01).结论 MMP-2、TGF-β1与胆道闭锁肝纤维化的发生、发展密切相关;抑制MMP-2、TGF-β1的表达有望阻止胆道闭锁患儿肝纤维化进程.  相似文献   
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