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991.
磷脂复合物对大鼠延缓衰老的作用 总被引:8,自引:0,他引:8
本文报告了磷脂复合物对9月龄SD大鼠血红细胞SOD活力,心肌丙二醛(MDA)含量及尾动脉容积脉搏图的影响,试验表明,基础饲料添加10%磷脂复合物原粉或稀释粉均能使血红细胞SOD活力显著增加,(P<0.01,P<0.05)。其中高剂量组心肌丙二醛含量显著降低(P<0.05),且容积脉搏图中降中峡相对深度显著增加(P<0.05)。结果提示,磷脂复合物有增加血红细胞SOD活力,降低脂质过氧化和减少尾动脉外周阻力的作用。 相似文献
992.
993.
膀胱移行细胞癌伴发前列腺腺癌五例 总被引:1,自引:1,他引:0
为了提高膀胱移行细胞癌伴发前列腺癌的诊断水平,对1986年至今收治经病理证实的5例膀胱移行细胞癌伴发前列腺腺癌患者,与膀胱肿瘤浸润前列腺及前列腺癌浸润膀胱两种疾病相比较。术前明确诊断需要注意:(1)前列腺直肠指诊必不可少;(2)术前前列腺穿刺活检可防止漏诊,尤其对可疑前列腺癌者更有必要;(3)膀胱镜检查、活检,前列腺特异性抗原检测具有一定意义。明确诊断对指导治疗及判断预后具有重要意义。 相似文献
994.
995.
996.
The potent inhibitory effects of cisapride, a specific blocker for human ether-a-go-go-related gene (HERG) channel, on gastric cancer cells 总被引:4,自引:0,他引:4
BACKGROUND: Ion channels may play a role in carcinogenesis. Human ether-a-go-go-related gene (HERG) encoding one of the components of delayed rectifier potassium currents has been indicated to be involved in tumor cell growth and death. Our aim is to investigate the effects of cisapride, a specific blocker for HERG channel, on human gastric cancer cells. METHODS: The effects of cisapride on the proliferation, clonogenicity, cell cycle and apoptosis of gastric cancer cells were evaluated by MTT assay, clonogenicity assay, flow cytometry and transmission electron microscopy. The expression of HERG mRNA and protein in gastric cancer cells and tissues was measured by RT-PCR, Western blot and immunohistochemistry, respectively. RESULTS: HERG mRNA and protein were exclusively expressed in gastric cancer cells. The HERG protein was localized in the cytoplasm and membrane of the gastric cancer cells. The proliferation of gastric cancer cells expressing HERG protein was inhibited in a time- and dose-dependent manner when treated with cisapride (P<0.05). The clonogenicity of gastric cancer cells treated with cisapride (100 nM) was reduced (P<0.05). Flow cytometric analysis indicated that cisapride tends to inhibit gastric cancer cells entering S phase from G(1) phase in the cell cycle (P<0.05). Apoptotic cells were found increased in gastric cancer cells treated with cisapride by both flow cytometry and electron microscopy. CONCLUSIONS: As HERG channel blocker, cisapride, can inhibit the growth of gastric cancer cells by altering distribution of cell cycle and inducing apoptosis so as to be of potential value in the treatment of gastric cancer. 相似文献
997.
998.
Pan ZG Kashuba VI Liu XQ Shao JY Zhang RH Jiang JH Guo C Zabarovsky E Ernberg I Zeng YX 《Cancer biology & therapy》2005,4(10):1116-1122
High frequency loss of 3p21.3 region is a common event in various kinds of tumors including nasopharyngeal carcinoma (NPC). RASSF1A has been identified as a putative tumor suppressor gene residing in this region. Chromosome alterations and epigenetic changes are commonly observed as mechanisms for inactivation of RASSF1A function. In this study, we applied the PCR-cloning-sequencing strategy to examine somatic mutations in RASSF1A in NPC tissues as compared with the sequences detected in the matched peripheral blood lymphocytes. Our results revealed a high incidence of RASSF1A mutation in primary tumor tissues of NPC. There are totally 35 mutations identified in 74% (17/23) of these NPC cases, including 30 transitions, three transversions and two deletions. Most of these mutations result in amino acid changes: three nonsense (stop codon) mutations, two-1 bp deletion (frameshift), 26 missense and the remaining four are synonymous (silent). No obvious 'hot-spot' mutations were observed in this study. A similarly high rate (74%) of promoter methylation of RASSF1A was also detected in the same group of NPC tissues, but no significant correlation between mutation and methylation was detected. Our results suggest various mechanisms involved in inactivation of RASSF1A function and indicate a critical role of RASSF1A in NPC development. 相似文献
999.
Nonylphenol and Nonylphenol Ethoxylates in River Water, Drinking Water,and Fish Tissues in the Area of Chongqing, China 总被引:7,自引:0,他引:7
Shao B Hu J Yang M An W Tao S 《Archives of environmental contamination and toxicology》2005,48(4):467-473
Little attention has been paid to the estrogenic-like compounds, such as 4-nonylphenol (4-NP) and its potential precursor nonylphenol ethoxylates (NPEOs), in China although its usage is huge. Water samples and corresponding drinking water samples were seasonally collected at five sites of each of the two main rivers in Chongqing Area. Individual nonylphenol ethoxylates (NPEOs) and 4-NP in the Changjiang River and Jialingjiang River were detected by normal-phase liquid chromatography electrospray ionization mass spectrometry and gas chromatography-mass spectrometry. The results indicated that of the five sampling points in the two rivers, NPEOs were the dominant pollutant in April and December with the similar distribution profile, and total NPEOs with different ethylene oxide lengths were 6.9–97.6 g/L in April and 2.5–52.7 g/L in December. However, NP was the dominant pollutant in July with a concentration of 1.7–7.3 g/L. Corresponding drinking water samples derived from river water as source suggested that the conventional water treatment process used in the five waterworks could remove NPEOs from the source water with high removal efficiency (>99%). The 4-NP removal efficiency, however, varied in a range of 62% to 95%, leaving a significantly high concentration of NP (0.1 to 2.7 g/L) in drinking water in July. Fish samples taken in December 2000 contained 4-NP of 1.9g/g and NPEOs of 0.4–48.3g/g, with the highest concentration level found in liver. 相似文献
1000.
丙型肝炎病毒感染患者13~14年后病毒组织学随访观察 总被引:2,自引:0,他引:2
Rao HY Wei L Zhao JM Sun DG Guo F Ma H Fang JL Shao J Zhang LF Sun Y Wang H 《中华医学杂志》2005,85(17):1166-1170
目的了解丙型肝炎病毒(HCV)感染后持续活动者的临床转归和肝脏组织学情况。方法5例因输血而感染丙型肝炎者,为女性,4例因单采血浆还输血球而感染丙型肝炎者,为男性,总共9例,所有感染者感染时间、感染途径清楚。采用炎症分级纤维化分期以及修正的Knodell评分对肝脏活检组织的炎症和纤维化程度进行评价,超声检查,血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)采用速率法,抗HCV采用酶联免疫吸附试验(ELISA)方法,HCVRNA定性检测采用RocheCobasHCV聚合酶链反应(PCR)试剂盒,HCVRNA定量采用BayerHCV分枝DNA(bDNA)试剂盒,HCVRNA基因型采用BayerLiPA基因型分析方法。结果(1)9例慢性丙型肝炎感染者共随访13~14年,其间于诊断时、1992、1995、1999、2003、2004年共检测6次ALT水平,均高于正常上限值(ULN)。(2)2004年检测9例慢性丙型肝炎感染者HCVRNA定性均为阳性,定量从3.57×108拷贝/L~7.21×109拷贝/L,大于2.00×109拷贝/L者5例。3例感染者为基因2型,其余6例为基因1b型。(3)9例慢性丙型肝炎感染者超声诊断为慢性炎症轻度者3例(3/9),占33.3%;中度6例(6/9),占66.7%;重度0例;脂肪肝1例(1/9),占11.1%。未发现失代偿性肝硬化和原发性肝癌。(4)9例慢性丙型肝炎感染者的肝组织炎症活动度(HAI)分数为5~8.5分,纤维 相似文献