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991.
丙型肝炎病毒基因分型及其与干扰素治疗应答的关系 总被引:4,自引:0,他引:4
目的为了解山西省丙型肝炎病毒的基因型和基因型对干扰素疗效的预示价值。方法用HCV5’NC区酶切分型方法对94例丙型肝炎病人进行基因分型,并观察其中45例患者对干扰素α1b治疗的应答。结果显示HCVⅠ组(Ⅰ、Ⅱ型)感染80例(851%),HCVⅡ组(Ⅲ、Ⅳ型)感染12例(128%),HCVⅠ/Ⅱ组混合感染2例(21%)。在接受干扰素治疗的病例中,HCVⅠ组感染(35例)的应答率为371%,持续应答率为171%,而Ⅱ组感染(10例)的应答率为80%,持续应答率为60%,两组相比,有显著性差异(P<005,P<0025)。结论表明山西省以HCVⅠ组感染为主,干扰素对HCVⅡ组感染的疗效优于HCVⅠ组感染,HCV基因型有预测干扰素疗效的意义。 相似文献
992.
Direct and endothelial cell-mediated effect of cyclosporin A on the proliferation of rat smooth muscle cells in vitro. 总被引:2,自引:1,他引:2
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D. Leszczynski Y. Zhao T. J. Yeagley M. L. Foegh 《The American journal of pathology》1993,142(1):149-155
Cyclosporin A (CsA) has been suggested to potentiate graft vascular disease by stimulation of smooth muscle cell (SMC) proliferation. Both the in vitro and in vivo data are discordant, showing both stimulatory and inhibitory effects of CsA on vascular SMC proliferation. The direct and endothelial cell-mediated effects of CsA on vascular SMC proliferation were examined in vitro using the incorporation of [3H]thymidine. All experiments were done in serum-free conditions. The exposure of SMC to CsA (0.0001 to 0.1 micrograms/ml) had no effect on proliferation. High doses of CsA (0.5 to 10.0 micrograms/ml) were toxic to the SMC and endothelial cells; 90% of SMC population died within 3 to 6 days of exposure to 10.0 micrograms/ml CsA. In the studies on the endothelial cell-mediated effect of CsA, the endothelial cell-conditioned medium (ECCM) significantly increased SMC proliferation. This stimulatory effect was significantly attenuated when the ECCM was obtained from endothelial cells exposed to CsA. Endothelin (ET) is suggested to be an endothelial-cell-derived growth factor for SMC, and implicated as a possible cause of the uncontrolled proliferation of SMC during development of graft vascular disease. Exposure of SMC to levels of recombinant ET similar to the levels found in the ECCM (0.19 + 0.01 pg/ml) significantly increased SMC proliferation. CsA increased fivefold ET concentration in the ECCM. However, despite this rise in ET levels, there was a 45% decrease in SMC proliferation. In conclusion, CsA does not exert a direct modulatory effect on SMC proliferation in vitro, but may inhibit SMC proliferation indirectly via endothelial cell-derived factors. These unidentified factor(s) inhibit SMC proliferation and abolish the mitogenic effect of ET on SMC. 相似文献
993.
994.
Na+ channel expression and neuronal function in the Na+/H+ exchanger 1 null mutant mouse 总被引:2,自引:0,他引:2
Mice lacking Na(+)/H(+) exchanger 1 (NHE1) suffer from recurrent seizures and die early postnatally. Although the mechanisms for seizures are not well established, our previous electrophysiological work has shown that neuronal excitability and Na(+) current density are increased in hippocampal CA1 neurons of these mutant mice. However, it is unknown whether this increased density is related to altered expression or functional regulation of Na(+) channels. In this work, we asked three questions: is the increased excitability limited to CA1 neurons, is the increased Na(+) current density related to an increased Na(+) channel expression, and, if so, which Na(+) channel subtype(s) is upregulated? Using neurophysiological, autoradiographic, and immunoblotting techniques, we showed that both CA1 and cortical neurons have an increase in membrane excitability and Na(+) current density; Na(+) channel density is selectively upregulated in the hippocampus and cortex (P < 0.05); and Na(+) channel subtype I is significantly increased in the hippocampus and Na(+) channel subtype II is increased in the cortex. Our results demonstrate that mice lacking NHE1 upregulate their Na(+) channel expression in the hippocampal and cortical regions selectively; this leads to an increase in Na(+) current density and membrane excitability. We speculate that neuronal overexcitability due to Na(+) channel upregulation in the hippocampus and cortex forms the basis of epileptic seizures in NHE1 mutant mice. 相似文献
995.
996.
18例恶性苗勒混合瘤临床病理分析 总被引:1,自引:0,他引:1
目的:探讨女性生殖系统恶性苗勒混合瘤(MMMT)的临床与病理特征。方法:对18例女性生殖系统MMMT进行光镜观察及免疫组化染色,结合临床资料进行分析,对9例进行了术后随访。结果:各部位MMMT的形态特征相似,均含有上皮及间叶两种组织成分,相互间有穿插和移行变化,组织成分形态多样,免疫组化有助于判断。恶性度与异型性、核分裂数及出血坏死程度有关。预后与临床分期有关。化疗有效。结论:MMMT的诊断主要依据组织形态学,预后与临床分期有关。 相似文献
997.
目的 :为了开发西洋参在临床医学方面的应用 ,提高CPHD病人的各项免疫指标。方法 :选择 4 0例CPHD病人 ,分成用药组 2 0例 ,对照组 (非用药组 ) 2 0例 ,通过流式细胞术检测病人外周血中T淋巴细胞亚群中各亚群所占的比例来反映机体的细胞免疫状态。结果 :通过两组临床研究观察 ,用药组疗效优于对照组 (P <0 0 5 )。西洋参茎叶皂甙可直接作用于淋巴细胞分化成熟过程 ,具有增强和调节CPHD病人机体免疫功能的作用。结论 :合理应用西洋参茎叶茎叶皂甙对改善CPHD病人免疫功能低下和紊乱状态 ,具有重要临床意义。 相似文献
998.
从临床收集耐亚胺培南的铜绿假单胞菌和鲍曼不动杆菌共50株,进行头孢他啶和2-巯基乙醇的表型协同试验(CAZ ME),然后进行金属酶IMP-1基因的PCR检测。选取IMP-1阳性株测序,用PCR方法检测有无一类整合子基因(IntI1)。表型的检测发现有28株为协同阳性,其中铜绿假单胞菌27株,鲍曼不动杆菌1株。PCR和测序检测出其中一株铜绿假单胞菌含有IMP-1基因,同时也含有IntI1基因。首次在中国西部地区发现产IMP-1型金属酶、同时也含有一类整合子的铜绿假单胞菌,对于临床上研究细菌的耐药性传播具有重要意义。 相似文献
999.
Accurate and efficient simulation of an x-ray transform for representative structures plays an important role in research and development of x-ray CT, for the evaluation and improvement of CT image reconstruction algorithms, in particular. Superquadrics are a family of three-dimensional objects, which can be used to model a variety of anatomical structures. In this paper, we propose an algorithm for the computation of x-ray transforms for superellipsoids and tori with a monochromatic x-ray. Their usefulness is demonstrated by projection and reconstruction of a superquadric-based thorax phantom. Our work indicates that superquadric modeling provides a more realistic visualization than quadratic modeling, and a faster computation than spline methods. 相似文献
1000.