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991.
应用生物素抗生物素过氧化酶法对103例乳腺癌石蜡切片进行雌激素受体检测,结果发现雌激素受体阳性率在导管内癌中较高,占71%,而在浸润性导管癌、髓样癌中较低,分别占57%、29%。分析了雌激素受体和组织类型关系,探讨了它和组织分级及核分级之间的联系。雌激素受体阳性率随组织分级升高而降低,随核的分级升高而增加。说明乳腺癌组织分化好,雌激素受体表达倾向阳性,而分化低的肿瘤,雌激素受体表达倾向阴性。雌激素受体阳性患者比阴性患者复发率低,存活时间长,预后好,其检测有助于判断患者预后,安排合理的治疗方案,提高治愈率。  相似文献   
992.
This study examined the impact of perceived stress on responses to messages that encouraged the performance of health promotion and disease detection behaviors. It was hypothesized that increases in perceived stress would be associated with decreased processing of messages encouraging disease detection behaviors, and that increases in perceived stress would not effect the processing of messages encouraging health promotion behaviors. To test these hypotheses participants completed a perceived stress measure and then read a message that encouraged the performance of either a health promotion or a disease detection behavior. Then the participants were asked to indicate their agreement with the message and to attempt to recall the message. The results indicated that participants experiencing higher levels of perceived stress spent less time reading and recalled less of the messages about detection behaviors than of the messages about promotion behaviors. When participants were experiencing lower levels of perceived stress these differences disappeared.
  相似文献   
993.
测量70个西藏现代藏族人颅40项指标;计算指数16项;根据指数确定颅型,额型,颌型,眶型,鼻型与腭型;进行数理统计;观察性别差异,发现男发性间各测量值差显著,  相似文献   
994.
目的研究路氏乳杆菌(Lactobacillus reuteri,也称罗伊氏乳杆菌)JCM1081菌体表面蛋白对其黏附HT-29细胞的影响。方法将路氏乳杆菌JCM1081菌体进行胰蛋白酶、蛋白酶K处理;用氯化锂和盐酸胍对乳杆菌表面的蛋白进行抽提,进行SDS-PAGE后与黏蛋白受体进行Western blot,并对杂交阳性蛋白进行质谱分析鉴定。结果路氏乳杆菌JCM1081菌体经胰蛋白酶、蛋白酶K处理后,其对HT-29细胞的黏附力显著下降(P<0.01);用氯化锂去除路氏乳杆菌JCM1081菌体外表面的S层蛋白后,路氏乳杆菌JCM1081对HT-29细胞的黏附力无显著变化;Western blot结果显示相对分子质量(Mr)为29×103和14×103的两种菌体表面蛋白与黏蛋白受体杂交中出现了强阳性;质谱分析结果显示29×103蛋白与路氏乳杆菌ATCC55730的h0793蛋白相似性高达71.1%。结论路氏乳杆菌JCM1081菌体表面的蛋白参与了乳杆菌的黏附,其中29×103和14×103的两种胞壁表面蛋白能够特异地识别黏蛋白受体并与之结合,29×103蛋白属ABC转运蛋白家族。  相似文献   
995.
The BXD2 strain of mice is one of approximately 80 BXD recombinant inbred (RI) mouse strains derived from an intercross between C57BL/6J (B6) and DBA/2J (D2) strains. We have discovered that adult BXD2 mice spontaneously develop generalized autoimmune disease, including glomerulonephritis (GN), increased serum titres of rheumatoid factor (RF) and anti-DNA antibody, and a spontaneous erosive arthritis characterized by mononuclear cell infiltration, synovial hyperplasia, and bone and cartilage erosion. The features of lupus and arthritis developed by the BXD2 mice segregate in F2 mice generated by crossing BXD2 mice with the parental B6 and D2 strains. Genetic linkage analysis of the serum levels of anti-DNA and RF by using the BXD RI strains shows that the serum titers of anti-DNA and RF were influenced by a genetic locus on mouse chromosome (Chr) 2 near the marker D2Mit412 (78 cm, 163 Mb) and on Chr 4 near D4Mit146 (53.6 cm, 109 Mb), respectively. Both loci are close to the B-cell hyperactivity, lupus or GN susceptibility loci that have been identified previously. The results of our study suggest that the BXD2 strain of mice is a novel model for complex autoimmune disease that will be useful in identifying the mechanisms critical for the immunopathogenesis and genetic segregation of lupus and erosive arthritis.  相似文献   
996.
BACKGROUND: Schneider's first-rank symptoms involve an alienated feature of the sense of one's own mental or physical activity. To clarify the brain morphological basis for the production of these symptoms, volumes of the frontal and medial temporal regions and their clinical correlates were examined in patients with schizophrenia. METHOD: Twenty-two patients with schizophrenia and 44 age- and gender-matched healthy control subjects were included. All patients were in their psychotic episodes with definite Schneiderian symptoms, rated by using the Scale for Assessment of Positive Symptoms. Volumetric measurements of high-resolution magnetic resonance imaging were performed in the prefrontal area, cingulate gyrus, and precentral gyrus, and the medial temporal structures such as the amygdala, hippocampus, and parahippocampal gyrus. RESULTS: Patients had significantly decreased volumes in the cingulate gray matter and the amygdala compared to controls. In the patient group, Schneiderian symptom severity showed significant inverse correlations with volumes of the right posterior cingulate gray matter and of the left anterior parahippocampal gyrus. CONCLUSIONS: Schneiderian symptoms may be associated with morphological abnormalities in the limbic-paralimbic regions such as the cingulate gyrus and parahippocampal gyrus, which possibly serve the self-monitoring function and the coherent storage and reactivation of information.  相似文献   
997.
998.
本文用组织化学方法,选择能反映神经组织糖代谢三个途径的关键酸及碱性磷酸酶,对正常SD系大鼠海马酶活性进行半定量研究.结果CA1区锥体层琥珀酸脱氢酶(SDH)及细胞色素氧化酶(CCO)呈轻度反应,葡萄糖-6一磷酸脱氢酶(G—6—PD)及乳酸脱氢酶(LDH)呈强阳性.腔隙分子层LDH、G—6—PD呈轻度活性,CCO、SDH呈强阳性.CA1区锥体层碱性磷酸酶(AKP)活性最弱.讨论了酶活性不同与记忆的关系及临床意义.  相似文献   
999.
Minor lymphocyte stimulating locus (Mls) gene products in association with mouse major histocompatibility complex (MHC) class II molecules are known to determine the repertoire of T-cell receptor (TCR) in mature T cells. In order to test whether human class II molecules can present mouse Mls, HLA-DQ beta transgenic mice were generated. The expression and function of the DQ beta transgene were studied in the progeny of one selected founder which was H-2f and H-2E negative. In these mice, DQ beta molecules pairing with mouse A alpha chain and invariant chain are expressed on the cell surface in a tissue-specific manner. When the DQ beta gene was bred into the Mls-1a strain DBA/1 (H-2q), T cells bearing V beta 6 and V beta 8.1 TCR were clonally deleted in the thymus of DQ beta+ transgenics but not in DQ beta-negative full sibs. Thus, the data presented here clearly demonstrate that the human MHC DQ beta chain can present Mls in the clonal deletion of T cells. Our results also suggest the requirement for an interaction between CD4 and class II molecules (alpha chain) for clonal deletion of T cells to occur.  相似文献   
1000.
目的 对表面磁性膜血管内支架进行生物相容性研究,为该支架的临床应用提供实验依据.方法 通过溶血实验、动态凝血时间实验、急性全身毒性实验、皮内刺激实验、细胞毒性实验、热源实验、过敏实验、体内植入实验综合评价表面磁性膜血管内支架的生物相容性.结果 表面磁性膜血管内支架无溶血反应及凝血功能的改变,无急性全身毒性反应,无热源反应,支架材料中不存在致敏性物质;支架材料动物体内植入在初期有轻度的炎性反应,12周后炎性反应基本消失,未见炎性细胞浸润积聚现象.结论 表面磁性膜血管内支架具有良好的生物相容性,其应用于临床具有可行性和安全性.  相似文献   
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