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51.
目的研究低氧培养大鼠心肌细胞Na 通道基因SCN5A mRNA表达的变化,并探讨其与丙二醛(M alond ialhyde,MDA)含量及超氧化物歧化酶(superoxide d ismutase,SOD)活性的关系。方法培养大鼠心肌细胞,检测各组培养液氧分压。用RT-PCR检测SCN5A mRNA表达,检测培养液MDA含量和细胞SOD活性。结果与对照组相比:SCN5A mRNA相对表达量低氧1 h和6 h组显著增高(P<0.001)、低氧12 h和24 h组显著降低(P<0.001);MDA含量显著增高而SOD活性显著降低。结论心肌细胞Na 通道基因SCN5A在低氧1 h和6 h mRNA表达上调,而在低氧12 h和24 h mRNA表达下调,且与脂质过氧化和SOD相关。  相似文献   
52.
经鼻内窥镜选择性鼻中隔粘膜下切除术   总被引:4,自引:0,他引:4  
目的:探讨经鼻内窥镜选择性鼻中隔粘膜下切除术的意义及手术方法。方法:根据不同的手术目的对204例需要行鼻中隔手术的病人,经鼻内窥镜实施选择性鼻中隔粘膜下切除术。结果:采用该技术对单纯性鼻中隔偏曲患者手术临床治愈率100%,其手术有效治愈头痛、鼻阻及鼻出血等鼻中隔偏曲临床症状,达到临床治疗目的。未出现鼻腔粘连、鼻中隔穿孔等并发症。有2例形成鼻中隔血肿,经放置引流管处理后治愈。对于解除高位鼻中隔偏曲解剖异常引发的鼻窦炎,手术后效果良好。取鼻中隔软骨做为修补材料手术效果满意。结论:经鼻内镜选择性鼻中隔粘膜下切除术目的性强、方法灵活、创伤小、并发症少、手术效果确切。  相似文献   
53.
Ding Y  He L  Zhang Q  Huang Z  Che X  Hou J  Wang H  Shen H  Qiu L  Li Z  Geng J  Cai J  Han H  Li X  Kang W  Weng D  Liang P  Jiang S 《The Journal of pathology》2004,203(2):622-630
We previously identified the major pathological changes in the respiratory and immune systems of patients who died of severe acute respiratory syndrome (SARS) but gained little information on the organ distribution of SARS-associated coronavirus (SARS-CoV). In the present study, we used a murine monoclonal antibody specific for SARS-CoV nucleoprotein, and probes specific for a SARS-CoV RNA polymerase gene fragment, for immunohistochemistry and in situ hybridization, respectively, to detect SARS-CoV systematically in tissues from patients who died of SARS. SARS-CoV was found in lung, trachea/bronchus, stomach, small intestine, distal convoluted renal tubule, sweat gland, parathyroid, pituitary, pancreas, adrenal gland, liver and cerebrum, but was not detected in oesophagus, spleen, lymph node, bone marrow, heart, aorta, cerebellum, thyroid, testis, ovary, uterus or muscle. These results suggest that, in addition to the respiratory system, the gastrointestinal tract and other organs with detectable SARS-CoV may also be targets of SARS-CoV infection. The pathological changes in these organs may be caused directly by the cytopathic effect mediated by local replication of the SARS-CoV; or indirectly as a result of systemic responses to respiratory failure or the harmful immune response induced by viral infection. In addition to viral spread through a respiratory route, SARS-CoV in the intestinal tract, kidney and sweat glands may be excreted via faeces, urine and sweat, thereby leading to virus transmission. This study provides important information for understanding the pathogenesis of SARS-CoV infection and sheds light on possible virus transmission pathways. This data will be useful for designing new strategies for prevention and treatment of SARS.  相似文献   
54.
Fuzzy rules to predict degree of malignancy in brain glioma   总被引:2,自引:0,他引:2  
The current pre-operative assessment of the degree of malignancy in brain glioma is based on magnetic resonance imaging (MRI) findings and clinical data. 280 cases were studied, of which 111 were high-grade malignancies and 169 were low-grade, so that regular and interpretable patterns of the relationships between glioma MRI features and the degree of malignancy could be acquired. However, as uncertainties in the data and missing values existed, a fuzzy rule extraction algorithm based on a fuzzy min-max neural network (FMMNN) was used. The performance of a multi-layer perceptron network (MLP) trained with the error back-propagation algorithm (BP), the decision tree algorithm ID3, nearest neighbour and the original fuzzy min-max neural network were also evaluated. The results showed that two fuzzy decision rules on only six features achieved an accuracy of 84.6% (89.9% for low-grade and 76.6% for high-grade cases). Investigations with the proposed algorithm revealed that age, mass effect, oedema, post-contrast enhancement, blood supply, calcification, haemorrhage and the signal intensity of the T1-weighted image were important diagnostic factors.  相似文献   
55.
Mutations in the PKD1 gene are responsible for autosomal dominant polycystic kidney disease (ADPKD). Although PKD1 has been cloned and shown to be expressed at high levels in the fetal ureteric bud and ADPKD cystic epithelia in the human kidney, the function of its encoded protein, "polycystin-1" is unknown. In this study we used primary and immortalized human renal epithelial cell lines derived from normal fetal, adult, and ADPKD kidneys, that endogenously express PKD1, to study the biologic function of the polycystin-1 protein. ADPKD renal epithelial cells expressed high levels of polycystin-1 protein and showed increased adhesion to type I collagen by comparison with normal adult human renal epithelia that expressed little polycystin. Adherent ADPKD cells also expressed high levels of alpha2beta1-integrin and their attachment was inhibited by a functional monoclonal antibody to alpha2-integrin. Double labeling and confocal microscopy as well as coimmunoprecipitation analysis showed overlapping colocalization of polycystin-1 with alpha2beta1-integrin as well as with the focal adhesion proteins vinculin and paxillin in multiprotein clusters localized to focal areas of cell membrane contact with type I collagen matrix after short periods of attachment. Immunoprecipitation and Western immunoblot studies also showed that polycystin-1 was posttranslationally modified by tyrosine phosphorylation. These studies suggest that the PKD1-encoded protein is part of a large multiprotein complex in epithelial cells that functions in the regulation of extracellular matrix interactions with the plasma membrane and cell cytoskeleton.  相似文献   
56.
57.
孕妇睡眠质量与焦虑、抑郁的相关性研究   总被引:5,自引:0,他引:5  
目的,了解孕妇在妊娠期睡眠质量与焦虑抑郁情绪状态的相关关系。方法:采用匹茨堡睡眠质量指数量表,症状自评量表,状态-特质焦虑问卷,焦虑自评量表,抑郁自评量表定,对83例孕妇的睡眠质量,状态--特质焦虑,焦虑和抑郁状态水平进行调查分析。结果:孕妇的睡眠质量,入睡时间,睡眠时间,白天功能与焦虑和抑郁情绪症状呈正相关(P<0.05);孕妇睡眠质量与状态焦虑呈正相关关系(P<0.05),而入睡时间与特质焦虑呈正相关关系(P<0.05),结论;孕妇妊娠期睡眠质量与焦虑和抑郁情绪症状有正相关关系。  相似文献   
58.
目的:观察脂多糖(LPS)对大鼠肺微血管内皮细胞(RPMVECs)G蛋白的影响及甲基强的松龙的干预作用。方法:用流式细胞技术(FCM)检测G蛋白亚型的变化。结果:①10μg/ml LPS作用于RPMVECs30和90min后,Gsα蛋白水平较对照组显著下降。甲基强的松龙干预30和90min后,对LPS致RPMVECs膜Gsα蛋白水平的变化有显著抑制作用。②10μg/ml LPS作用于RPMVECs30和90min后,Giα蛋白水平较对照组显著下降。甲基强的松龙干预30和90min后,对LPS致RPMVECs膜Giα蛋白水平的变化有显著抑制作用。结论:①LPS诱导RPMVECS Gsα和Giα蛋白水平的变化可能是LPS诱导RPMVECs单层通透性增加的机制之一。②甲基强的松龙参与抑制LPS诱导RPMVECs单层通透性增加的作用。  相似文献   
59.
对博莱霉素肺纤维化大鼠模型不同时期作支气管肺泡灌洗液(BALF)细胞计数与分类、蛋白含量测定和磷脂及其组分测定,并与肺病理变化作对照分析。结果发现BALF细胞计数和分类与肺组织细胞浸润基本一致,BALF蛋白含量增加,磷脂酰甘油(PG)随病变进展而下降,磷脂酰肌醇(PI)和磷脂酰乙醇胺(PE)升高。PG/PI比值下降,PG/PI比值可作为肺纤维化的一种标志。  相似文献   
60.
在聚合物固体电解质(聚乙二醇不饱和聚酯网络-LiClO4)中进行吡咯聚合原位制得了聚吡咯/聚合物固体电解质双层复合膜。用扫描电镜观察复合膜的界面结构,用循环伏安和交流阻抗法研究了复合膜的电化学杂脱掺杂性能。结果表明,聚吡咯/聚合物固体电解质双层复合膜具有相互穿插渗透的固/固密接界面结构,这种界面结构改善了聚吡咯和聚俣物固体电解质间的界面接触,提高了聚吡咯在聚俣物固体电解质中的电化学掺杂脱掺杂性能。  相似文献   
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