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61.
A method of obtaining a vegetation sample in a culture-negative endocarditis is described. A combination of fluoroscopy and transesophageal echocardiography was utilized to obtain the sample. The results positively influenced the diagnosis and treatment in this 16-yr-old male with complex congenital heart disease. © 1996 Wiley-Liss, Inc.  相似文献   
62.
Objective. T cells treated with DNA methylation inhibitors overexpress lymphocyte function-associated antigen 1 (LFA-1), which results in autoreactivity, and the autoreactive cells cause a lupus-like disease in vivo, suggesting a mechanism by which some agents may cause drug-induced lupus. This study compared the effects of procainamide (Pca) and hydralazine (Hyd) with those of structural analogs, to determine if the degree of LFA-1 overexpression and T cell autoreactivity correlated with the ability of the agents to induce autoimmunity. Methods. Cloned murine T helper 2 cells were treated with Pca, N-acetylprocainamide, Hyd, Phthalazine, or hydroxyurea (HU). The treated cells were then compared for LFA-1 overexpression, autoreactivity, and the ability to induce autoimmunity in vivo. Results. Pca and Hyd were more potent than their analogs or HU in all 3 assays. Conclusion. The results support a relationship between LFA-1 overexpression, T cell autoreactivity, and autoimmunity, and suggest a mechanism by which Pca and Hyd, but not the analogs, may cause drug-induced lupus.  相似文献   
63.
Multidrug resistance (MDR) to anticancer drugs remains a serious obstacle to the success of cancer chemotherapy. Resveratrol, a polyphenol, present in natural products exerts anticancer activity and acts as a potential MDR inhibitor in various drug-resistant cancer cells. In the process of resensitization of drug-resistant cancer cells, resveratrol has been shown to interfere with ABC transporters and drug-metabolizing enzymes, increase DNA damage, inhibit cell cycle progression, and induce apoptosis and autophagy, as well as prevent the induction of epithelial to mesenchymal transition (EMT) and cancer stem cells (CSCs). This review summarizes the mechanisms by which resveratrol counteracts MDR in acquired drug-resistant cancer cell lines and provides a critical basis for understanding the regulation of MDR as well as the development of MDR-inhibiting drugs.  相似文献   
64.
Chan Su is a traditional Chinese medicine prepared from the dried white secretion of the auricular and skin glands of toads, and has been used as an oriental drug for the treatment of a number of diseases, including cancer. In this study, the potential of Chan Su (skin of Venenum Bufonis) to induce apoptosis in human lung carcinoma A549 cells was investigated. Treatment of A549 cells with skin of Venenum Bufonis resulted in the inhibition of cell growth and viability and the induction of apoptosis, which was shown by trypan blue counts, MTT assay, DAPI staining and flow cytometry analysis. The increase in apoptosis that was induced by skin of Venenum Bufonis was correlated with down-regulation of anti-apoptotic Bcl-2 expression, up-regulation of pro-apoptotic Fas ligand and death receptor 4, and a decrease in the mitochondrial membrane potential. Skin of Venenum Bufonis treatment induced the proteolytic activation of caspases and a concomitant degradation of poly(ADP-ribose)-polymerase and β-catenin protein. Cleavage of Bid and a down-regulation of the inhibitor of apoptosis family proteins were also observed in skin of Venenum Bufonis-treated A549 cells. Data from this study indicates that SVB induces the apoptosis of A549 cells through a signaling cascade of death receptor-mediated extrinsic and mitochondria-mediated intrinsic caspase pathways.  相似文献   
65.
青光眼(glaucoma)是一组视网膜神经节细胞及其轴突变性的进行性视神经病,其典型临床特征为视乳头凹陷性萎缩和特征性视野缺损,遗传因素在其发病过程中起着重要作用。本指南主要介绍单基因变异相关的青光眼,包括原发性先天性青光眼(primary congenital glaucom a,PCG)和原发性开角型青光眼(primary open-angle glaucoma,POAG)的致病基因、疾病诊断以及临床咨询等方面,旨在规范单基因青光眼临床分子遗传诊疗,为临床医生对单基因青光眼诊治和遗传咨询服务提供参考。  相似文献   
66.
Tse YC  Yung KK 《Brain research》2000,854(1-2):57-69
In order to characterize the expression of ionotropic glutamate receptor immunoreactivity in subpopulations of neurons in the rat substantia nigra pars reticulata (SNr), double labeling experiments were performed. Neurons in the reticulata were found to display GluR1, GluR2, GluR2/3, GluR4, N-methyl-D-aspartate receptor 1 (NMDAR1) and NMDAR2B immunoreactivity. Some of the reticulata neurons were shown to display GluR1 and GluR2 immunoreactivity or GluR2 and GluR4 immunoreactivity at the single cell level. In addition, subpopulations of reticulata neurons were characterized on the basis of the strong expression of parvalbumin (PV) and GABA transaminase immunoreactivity. All of the reticulata neurons that displayed strong immunoreactivity for PV or GABA transaminase also displayed immunoreactivity for GluR1, GluR2/3, GluR4, NMDAR1 and NMDAR2B. A tiny portion (around 15%) of reticulata neurons that display NMDAR1 immunoreactivity was found to be PV- or GABA-transaminase-negative. The present results indicate that native alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA)-type receptors and NMDA-type receptors in the rat substantia nigra are composed of heteromeric receptor subunits. The present findings further demonstrate that most of the AMPA-type and NMDA-type glutamate receptor subunits are primarily expressed by subpopulations of neurons in the rat SNr.  相似文献   
67.
The globus pallidus is believed to play a critical role in the normal function of the basal ganglia, and abnormal activity of its neurons may underlie some basal ganglia motor symptoms. A high density of benzodiazepine binding sites on GABAA receptors has been reported in the rat globus pallidus. The present study investigates the effect of activating the benzodiazepine site by the agonist zolpidem. In in vitro slices, 100 nM of zolpidem significantly prolonged the half decay time of both miniature and spontaneous inhibitory postsynaptic currents by 30.1 +/- 3.0% (n=12) and 17.8 +/- 2.4% (n=16), respectively, with no effect on their amplitudes and frequencies. In the behaving animal, when zolpidem was microinjected into the globus pallidus unilaterally, it caused a robust ipsilateral rotation (26.4 +/- 2.4 turns/30 min, n=8), significantly higher than that of control animals receiving vehicle injection (1.3 +/- 1.6 turns/30 min, n=6). This effect was in agreement with the in vitro effect of zolpidem in enhancing the action of GABA on postsynaptic GABAA receptors. All the effects of zolpidem, in vitro or in vivo, were sensitive to the benzodiazepine antagonist flumazenil, confirming the specificity on the benzodiazepine site. This finding on the effect of zolpidem on motor behavior provides a rationale for further investigations into its potential in the treatment of motor disorders originating from the basal ganglia.  相似文献   
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70.
Decay-accelerating factor (DAF) has been reported to be a cellular receptor for several enteroviruses. Buffalo green monkey kidney (BGMK) cells expressing human DAF (BGMK-hDAF cells) showed increased susceptibility and sensitivity to several types of enteroviruses compared to wild-type BGMK cells. When 17 frozen positive clinical samples were tested, BGMK cells detected 8 and BGMK-hDAF cells detected 16. Since the CaCo-2 cell line has been documented to support the replication of most enteroviruses, CaCo-2 cells were mixed with BGMK-hDAF cells in order to increase the number of viruses detected. Thirty-four frozen clinical samples that previously had tested positive for enteroviruses were tested, and the following numbers were detected: 33 of 34 by CaCo-2/BGMK-hDAF cells, 29 of 34 by CaCo-2/BGMK cells, 28 of 34 by H292/RD (E-mix A) and A-549/BGMK (E-mix B) cells, and 26 of 34 by MRC-5 and pRhMK cells.  相似文献   
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