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101.
目的探讨膀胱癌细胞nm23蛋白表达量与丝裂霉素药物敏感性之间的相关性.为临床膀胱移行细胞癌治疗方案选择提供理论依据.方法对32例临床病理诊断为膀胱移行细胞癌标本采用S-P免疫组化和图像分析技术检测细胞的nm23蛋白表达量;同时采用MTT法测定膀胱癌细胞对丝裂霉素的药物敏感性.结果膀胱癌nm23表达量与MMC抗药指数相关,相关指数为0.890(P<0.001).结论膀胱癌nm23蛋白表达量与MMC抗药指数呈正相关. 相似文献
102.
Effect of nitric oxide modulation on TGF-beta1 and matrix proteins in chronic cyclosporine nephrotoxicity 总被引:3,自引:0,他引:3
BACKGROUND: Chronic cyclosporine (CsA) nephrotoxicity is characterized by interstitial fibrosis and afferent arteriolar hyalinosis. L-arginine (L-Arg), the substrate for nitric oxide (NO) synthase and N-nitro-L-arginine-methyl ester (L-NAME), the NO synthase inhibitor, were shown to modulate acute CsA nephrotoxicity. However, the mechanism of fibrosis in chronic CsA nephrotoxicity remains unclear. Thus, we examined the effect of NO modulation on fibrosis and the expression of transforming growth factor-beta1 (TGF-beta1) and matrix proteins in chronic CsA nephrotoxicity. METHODS: Rats were administered CsA (7.5 mg/kg), CsA + L-Arg (1.7 g/kg), CsA + L-NAME (3.5 mg/kg), vehicle (VH), VH + L-Arg, and VH + L-NAME, and were sacrificed at 7 or 28 days. NO production, physiologic parameters, and histology were studied in addition to the mRNA expression of TGF-beta1, plasminogen activator inhibitor-1 (PAI-1) and the matrix proteins biglycan and collagens type I and IV by Northern and the protein expression of PAI-1 and fibronectin by enzyme-linked immunosorbent assay. RESULTS: While L-NAME strikingly reduced NO biosynthesis and worsened the glomerular filtration rate and CsA-induced fibrosis, L-Arg had the opposite beneficial effect. In addition, the CsA-induced up-regulated expression of TGF-beta1, PAI-1, and the matrix proteins biglycan, fibronectin, and collagen I was significantly increased with L-NAME and strikingly improved with L-Arg. Collagen IV expression was not affected. Also, NO modulation did not affect VH-treated rats. CONCLUSIONS: Chronic CsA nephrotoxicity can be aggravated by NO blockade and ameliorated by NO enhancement, suggesting that NO maintains a protective function. NO modulation was associated with a change in TGF-beta1 expression, which, in turn, was associated with alterations in matrix deposition and matrix degradation through its effect on PAI-1. 相似文献
103.
颗粒细胞瘤(GranularCelTumor,GCT)是一种罕见的肿瘤。常发生于舌、皮肤及皮下组织、乳腺等部位。呼吸道GCT发生率低,若累及呼吸道则以喉和支气管较多见。原发部位位于气管的GCT极少,截止到1986年英文文献仅有10例气管GCT报道,国内近13年未有气管颗粒细胞瘤报道,。本文报道1例30岁女性气管GCT患者,结合文献对气管GCT的组织发生、临床表现、病理特点、诊断与鉴别诊断以及治疗方法等问题进行讨论。 相似文献
104.
大鼠脑神经干细胞神经巢蛋白表达的流式细胞术检测 总被引:9,自引:1,他引:8
检测胎鼠及成年大鼠脑内神经干细胞特异性抗原神经巢蛋白的表达,判明啮齿类哺乳动物脑内神经干细胞存在的可能性及相应的部位。方法:显微手术下采取胎鼠及成年大鼠大脑与皮质下脑组织,间接荧光法标记nestin,以流式细胞术检测。结果胎鼠脑内普遍存在nestin阳性细胞,成年大鼠脑室旁组织中也存在nestin阳性细胞。 相似文献
105.
S. Yi J. R. Chen J. Viallet R. H. Schwall T. Nakamura M. S. Tsao 《British journal of cancer》1998,77(12):2162-2170
We have studied the mitogenic, motogenic and morphogenic effects of hepatocyte growth factor (HGF), also known as scatter factor (SF), on 15 non-small-cell lung carcinoma (NSCLC) cell lines that have had their ras genotype determined. HGF/SF stimulated proliferation in only three cell lines and exerted no mitogenic activity on six lines. The growth of the remaining six lines was inhibited. The mitogenic effects were not related to the ras genotype of these cell lines, but the inhibitory effect was more commonly observed in cell lines with relatively high levels of Met/HGF receptor (HGFR) expression. HGF/SF induced or enhanced both scatter activity on monolayer culture and single-cell invasion in collagen gels in approximately half of these cell lines. Although the ras genotype of tumour cells did not influence the HGF/SF-induced motogenic activity, cell lines with the mutant ras genotype more commonly demonstrated a spontaneous motogenic activity than those with the wild-type ras genotype. When tumour cells were grown in collagen gels, HGF/SF induced irregular branching extensions of cell aggregates formed by five out of eight adenocarcinoma cell lines, but significant lumen morphogenesis was distinctly absent. The presence of autocrine HGF/SF loop in these tumour cell lines did not influence their spontaneous or HGF/SF-induced mitogenic, motogenic or morphogenic activities. Overall, our data suggest that stimulation of cell motility, rather than proliferation or differentiation, is the predominant paracrine effect of HGF/SF on NSCLC cells in vitro. 相似文献
106.
药品说明书是药品获批准上市后的重要证明文件之一,是对被批准的适应症、用法、用量等有关用药重要信息的详细说明,是指导医患用药的关键依据。在《中华人民共和国药品管理法》、《药品注册管理办法》(试行)以及国家食品药品监督管理局局23号令等法律、法规和条例中,对药品说明书及相关内容明确了其要求和责任等,这对认识说明书的作用和地位,并且对其进行制订和核准都起着重要的指导作用。 相似文献
107.
Mortality: What Are the Roles of Risk Factor Prevalence,Screening, and Use of Recommended Treatment?
K. Robin Yabroff PhD MBA ; William F. Lawrence MD MSc ; Jason C. King MPH ; Patricia Mangan BA ; Kathleen Shakira Washington MPA ; Bin Yi MS; Jon F. Kerner PhD ; Jeanne S. Mandelblatt MD MPH 《The Journal of rural health》2005,21(2):149-157
CONTEXT: Despite advances in early detection and prevention of cervical cancer, women living in rural areas, and particularly in Appalachia, the rural South, the Texas/Mexico border, and the central valley of California, have had consistently higher rates of cervical cancer mortality than their counterparts in other areas during the past several decades. METHODS: This paper reviews the published literature from 1966 to July 2002 to assess three potential pathways underlying this excess mortality--high human papilloma virus (HPV) prevalence, lack of or infrequent screening and advanced disease at diagnosis, and under-use of recommended treatment and shorter survival. FINDINGS: Living in rural areas may impose barriers to cervical cancer control, including lack of transportation and medical care infrastructures. Population characteristics that place women at greater risk for developing and dying from cervical cancer, such as low income, lack of health insurance, and physician availability, are concentrated in rural areas. Published data, however, are insufficient to identify the key reasons for the observed mortality patterns. CONCLUSIONS: At this time, given the lack of definitive evidence in the published literature, decisions about priorities in areas with high rates of cervical cancer mortality will depend on knowledge of current levels of screening, incidence, and stage distribution; and service delivery infrastructures, resources, and acceptability of interventions to the target population. 相似文献
108.
109.
医院设备购置中的供应商选择 总被引:3,自引:6,他引:3
供应商选择在医院设备采购中越来越重要。本文构建了医疗设备的供应商评价体系,然后应用模糊综合评判方法建立了供应商评价模型,最后给出算例予以说明。 相似文献
110.