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991.
采用聚合酶链反应(PCR)技术,对42例肝活切组织石蜡切片中乙型肝炎病毒(HBV)DNA进行检测,并与乙肝表面抗原(HBsAg)的免疫组织化学及血清学检测进行比较,HBV-PCR阳性率为73.8%,高于组织及血清HBsAg阳性率(分别为59.5%和50.0%)。3例病理形态呈肝炎改变,而血清HBsAg(─)的肝组织中有2例检出HBV-DNA,提示PCR的高度敏感性和准确性。83.3%的门脉性肝硬变和87.5%的肝细胞癌组织中HBV-PCR呈阳性,进一步证实了上述两病与HBV的关系密切。我们还发现肝细胞淤胆患者HBV感染率较高,HBV-DNA及组织HBsAg阳性比例各为6/9和4/8。 相似文献
992.
Mg^2+对离体灌流内皮素的大鼠心脏功能的影响 总被引:1,自引:0,他引:1
本实验在离体大鼠心脏灌流模型上,观察到10~(-9)mol/L内皮素灌流引起心肌挛缩,心功能降低,冠脉灌流量减少,以及心肌Ca~(2 )聚积,Mg~(2 )丧失等表现。灌流液含低镁(0.12mmol/L)时内皮素对心脏的上述作用显著增强,而在含高镁(4.8mmol/L)时明显减弱。Mg~(2 )影响内皮素对心脏作用的机制可能与其抑制心肌Ca~(2 )内流有关。实验结果提示避免缺镁,适当补充Mg~(2 )对于防治伴有循环内皮素水平增加的疾病或病理过程中的心脏损伤可能具有临床意义。 相似文献
993.
目的:了解肺炎克雷伯杆菌与膀胱上皮细胞的相互关系,观察肺炎克雷伯杆菌在人膀胱上皮细胞抹T24中生存的动态变化。方法:采用肺炎克雷伯杆菌临床分离抹03138侵袭T24细胞,并用庆大霉素杀死细胞外的细菌,分别于细菌进入细胞后的4、24、48及72h裂解细胞,释放出细胞内的活细菌,用平板菌落计数法计数胞内活菌数。结果:T24细胞内的肺炎克雷伯杆菌03138抹在实验48h内有一定生长,试验72h细胞内活菌数量明显减少。加入细胞因子(TNF-αd和INF-γ)可以促进上皮细胞清除胞内细菌。结论:膀胱上皮细胞清除进入细胞内的肺炎克雷伯杆菌,可能是泌尿道天然免疫的一种防御机制,而细胞因子可以调控上皮细胞的抗菌作用。 相似文献
994.
Our purpose in this work was to assess the reliability of the calibration coefficient for magnetic resonance water proton chemical shift temperature mapping. Over a six month period, the calibration coefficient was measured 15 times in several different phantoms. A highly linear relationship between water proton chemical shift and temperature change was found. The average temperature calibration coefficient determined from all studies was 0.009+/-0.001 ppm/degrees C. Four of the 15 studies were conducted on the same day using the same phantom. The average temperature calibration coefficient of these four studies was 0.0096+/-0.0001 ppm/degrees C. 相似文献
995.
Induction of vascular adhesion protein-1 during liver allograft rejection and concomitant cytomegalovirus infection in rats 总被引:3,自引:0,他引:3 下载免费PDF全文
Martelius T Salmi M Wu H Bruggeman C Höckerstedt K Jalkanen S Lautenschlager I 《The American journal of pathology》2000,157(4):1229-1237
Vascular adhesion protein-1 (VAP-1) is an adhesion molecule controlling lymphocyte recirculation through high endothelial venules of the lymph nodes. It has also been shown to be induced and to mediate lymphocyte adhesion at sites of inflammation. We studied the expression of VAP-1 and two other inducible adhesion molecules ICAM-1 and VCAM-1 in our experimental model of rat liver allograft rejection and, in addition, the effect of concomitant rat cytomegalovirus (RCMV) infection on this expression. Expression of VAP-1, ICAM-1, and VCAM-1 was studied in rat liver allografts with or without RCMV infection, isografts, and normal rat liver. Immunoperoxidase technique and monoclonal antibodies including a novel anti-VAP-1 reagent were used. VAP-1 expression was induced by acute rejection in sinusoids, hepatocytes, and also in bile ducts, when compared to the isografts or normal liver, where only blood vessels were consistently positive. Sinusoidal and hepatocyte expression of VAP-1 was prolonged by the presence of RCMV. ICAM-1 and VCAM-1 expression was also induced by acute rejection. However, RCMV increased sinusoidal VCAM-1 expression compared to uninfected grafts. The present experimental study shows that VAP-1 is up-regulated in acute rejection of liver allografts, and that this up-regulation is prolonged by RCMV infection. 相似文献
996.
用自行设计的踏车多指标心血管功能评价系统(E系统),对正常人,冠心病患者、心肌梗塞患者三组进行踏车运动前后Q—Tc变化及运动前后心血管功能评定。对静息时或运动后Q—Tc延长诊断冠心病价值及运动前后心血管功能变化规律的敏感性、特殊性分别进行对照和探讨。 相似文献
997.
Anderson RA; Wallace AM; Kicman AT; Wu FC 《Human reproduction (Oxford, England)》1997,12(8):1657-1662
Administration of supraphysiological doses of testosterone to normal men
causes inhibition of spermatogenesis, but while most become azoospermic,
30-55% maintain a low rate of spermatogenesis. We have investigated whether
there are differences in endogenous androgen production, of testicular and
adrenal origin, which may be related to the degree of suppression of
spermatogenesis. Thirty-three healthy Caucasian men were given weekly i.m.
injections of 200 mg testosterone oenanthate (TE), 18 became azoospermic,
while 15 remained oligozoospermic. Urinary excretion of epitestosterone, a
specific testicular product, was reduced to <10% of pretreatment values,
with no differences between the groups. Similar results were obtained for
other markers of testicular steroidogenesis. Urinary and plasma adrenal
androgens were also reduced during TE treatment: a statistically
significant decrease in both (P < 0.001 and P < 0.05 respectively)
was seen in the azoospermic but not oligozoospermic responders. These
results suggest that testicular steroidogenesis is decreased to <10% by
the administration of supraphysiological doses of exogenous testosterone.
Differences in the degree of ongoing steroidogenesis in the testis do not
appear to account for incomplete suppression of spermatogenesis, thus
differences in androgen metabolism may underlie this heterogeneous
response. A small but significant reduction in secretion of adrenal
androgens was also detectable, the relevance of which is unclear.
相似文献
998.
动脉粥样硬化斑块中内皮素生成及分布的免疫组织化学观察 总被引:1,自引:0,他引:1
应用免疫组化方法对人动脉粥样硬化(AS)斑块中内皮素(ET)进行分析,发现除内皮细胞外,增生的平滑肌细胞(SMC)中也含有大量的内皮素;在内皮剥脱的大鼠胸主动脉,增生的内膜SMC能产生丰富的内皮素。内皮素放射免疫测定证实SMC增生的活跃程度与内皮素量呈正比。提示内皮素合成增多与AS斑块内SMC增生关系密切。 相似文献
999.
One contributing factor to the loss of T cells in AIDS may be the impaired ability of T cell precursors to expand, as reflected in a decreased ability of patient cells to form T cell colonies in agar. We and others have noted such a defect in people with AIDS and ARC, and have found that suppressor cells and suppressive plasma contribute to decreased T-CFC formation. We report here that the reducing agents 2-mercaptoethanol (2-ME) and n-acetyl cysteine (NAC) can enhance colony formation in vitro. In part, 2-ME can reverse the defect in T cell colony-forming cells (T-CFC) formation by overcoming the effect of suppressor cells. In a group of 46 AIDS patients, T-CFC formation was initially 42 +/- 8% (mean +/- s.e.) that of control levels. 2-ME caused an increase of 401 +/- 76% in T-CFC formation which was significantly greater than the increase in control T-CFC formation; it also significantly enhanced T-CFC formation by cells from ARC patients. Suppressor cell activity from ten AIDS patients decreased from 58 +/- 21% to 12 +/- 10% when 2-ME was added. Similar data were obtained from 14 ARC patients. NAC, a related antioxidant with low toxicity, also enhanced T-CFC in cells of AIDS and ARC patients. Vitamin C generally did not increase T-CFC formation. The data suggest that certain antioxidants such as 2-ME and NAC may be useful in treatment protocols to enhance T cell numbers in patients with AIDS or ARC. 相似文献
1000.
Building a mouse model hallmarking the congenital human cytomegalovirus infection in central nervous system 总被引:6,自引:0,他引:6
Tang JL Wang ML Qiu JJ Wu D Hu W Shi BF Hu Y Li JP Tang J Wang M Qiu J Shi B Li J 《Archives of virology》2002,147(6):1189-1195
To investigate the mechanisms that human cytomegalovirus (HCMV) can vertically transmit from the placenta of mice to infect their offspring in the central nervous system (CNS) and cause congenital anomalies, and in order to provide basic research for preparing HCMV vaccine, we have developed a new type of mouse model of HCMV congenital CNS infection. Pure strain mice were propagated after being infected with HCMV. Then the degree of infection by HCMV to offspring was determined. The experiment shows that in the infection groups the mortality of fetal mice and the fatality of neonatal mice in one week are higher than that of the control groups (P < or = 0.05). At the same time we investigated the CNS of fetus's mice whose mothers were infected by HCMV. Our results showed: 1. The virus was successfully isolated from their cerebral cortex. 2. The signal of HCMV hybridization print was found in their nervous cell through in situ hybridization. 3. Especially human herpes virus-like particles and inclusion bodies in the plasm of nerve cell were found in the tissue of their brain under the electron microscope. This new type of mouse model of HCMV inherent CNS infection will help prepare HCMV vaccine and research HCMV congenital infection in CNS. 相似文献