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91.
Meghna R Adhvaryu Narshimha Reddy Minoo H Parabia 《African journal of traditional, complementary, and alternative medicines》2008,5(4):409-418
The anti-tumor activity and chemopreventive potential of four Ayurvedic herbs viz. Curcuma longa L., Ocimum sanctum L., Tinospora cordifolia (Wild) Miers ex Hook.f & Thomas and Zizyphus mauritiana Lam. were evaluated using Dalton Lymphoma ascites (DLA) tumor model in Swiss Albino mice. The outcome was assessed using survival time, peritoneal ascitic fluid (Tumor volume) and hematological indices as parameters. Animals were divided into five groups (n = 6) viz. one DLA control and four Herb + DLA treated groups. All the four herb + DLA groups were pre-treated with respective herbs for 7 days and hematological indices were measured for entire five groups. On day-8 animals were inoculated with 1×106 DLA cells i.p., and Herb + DLA groups were continued with oral herbal treatment for 21-days. Hematological parameters and tumor volume were assessed to find the effects of herbs. Short term in vitro cytotoxicity was determined by Trypan Blue exclusion method and LDH leakage assay using different concentrations of herbal extracts and 5-FU as a positive control and IC50 for each herbal extract and 5-FU were determined. Oral administration of crude herb increased the survival time and decreased the peritoneal ascitic fluid content significantly. Hb, RBCs and total WBC which were altered by DLA inoculation were restored significantly by all the herbs except O. sanctum. All the four herbs showed in vitro cytotoxic activity against DLA cell-line. Moreover inter group comparison of all the four herbs for anti-tumor activity showed efficacy in the following order- T. cordifolia > Z. mauritiana ≥ C. longa > O. sanctum respectively. 相似文献
92.
中学生学业能力倾向测验的初步编制 总被引:2,自引:1,他引:2
目的:编制一个适用于中学生的学业能力倾向测验。方法:采用理论与工作分析相结合的编制策略而成的中学生学业能力倾向测验包括A、B两个复本,均由三个分量表含七个分测验组成,分别测量语文.数理及图形等能力。研究样本由河北省石家庄市1424名中学生组成,并对其中468人分别进行信效度检验。结果:①各分测验原始分基本随年级升高而增长;②各分测验难度在0.46~0.54。鉴别指数在0.38~0.52;③各分量表及总分的重测相关系数在0.68~0.92,α系数在0.64~0.89.G系数在0.64~0.92;④探索性因素分析表明各分测验对基本能力因子均有中度以上的负荷,抽取的三个因子解释了总方差的72.18%(A式)和73.53%(B式);⑤测验分数与长一鞍团体智力测验、与教师评价均呈显著正相关。测验分数在不同年级之间存在显著差异。学习成绩的回归分析可见,测验分数与考试成绩显著正相关,语文及数理分量表进入考试总成绩的回归方程。结论:中学生学业能力倾向测验的条目质量及信效度符合心理测量学的基本要求。 相似文献
93.
培养细胞整装内质网三维结构的多态性 总被引:3,自引:0,他引:3
用高锰酸钾-锇酸固定法制备了5种培养细胞整装内质网标本,并在扫描电镜下对其三维结构进行了观察。观察结果表明内质网是由膜性小管构成的贯穿整个细胞质的管囊网络样膜性区室,并以多种形态深入到细胞伪足及突起中;细胞质中内质网则表现为簇状网络(见于GCM3T3细胞)、多态性多孔扁囊样网络、筛网状网络、条索状网络、大孔条索网状和细孔扁囊样分区网络、不规则管网状和多孔管囊分区网络(见于CV-1细胞)、细管网络(见于CCL187和CCL229细胞)、球囊网络(见于CCL187和A431细胞)和不规则管网状网络(见于A431细胞)等。内质网的这种多态性提示它是一种高度可变的结构,其可变性可能与细胞特性、分化程度、细胞功能状态及细胞骨架系统的分布变化等因素有关。 相似文献
94.
95.
目的 研究针对HBV X基因区设计的小干扰RNA(siRNA)表达载体质粒pGenesil-siHBV X 对HepG2.2.15细胞HBV表达和复制的抑制效果及特异性。方法 针对HBV X区设计siRNA表达载体质粒pGenesil- siHBV X。分别用培养液(空白对照)、脂质体Metafectene、pGenesil 空载体、pGenesil-siHK(阴性对照)、pGenesil-siAFP(特异性对照)、pGenesil-siHBV X处理或转染HepG2.2.15细胞各3次。于每次转染后24 h,取各组细胞培养上清液,用时间分辨荧光免疫测定技术检测上清液中HBsAg和HBeAg含量,用化学发光法检测AFP含量,用PCR荧光定量技术检测HBV-DNA复制水平。
结果 pGenesil-siHBV X转染能抑制HepG2.2.15细胞对HBV标志物的表达,且抑制作用随转染次数增加而增强。第3次转染后,pGenesil-siHBV X组细胞上清液中 HBsAg、 HBeAg和HBV-DNA检测结果分别为(6.26 ± 1.07)ng/ml 、(0.13 ± 0.05)Ncu/ml和(3.01 ± 0.40)×107拷贝/ml,与空白对照组的(22.50 ± 1.39)ng/ml、(1.12 ± 0.11)Ncu/ml和(12.33 ± 1.28)×107拷贝/ml比较,差异有统计学意义(t值分别为12.80、12.21、9.71,P < 0.05);pGenesil-siHBV X 转染不影响细胞对AFP的表达(t = 0.18,P = 0.86)。结论 pGenesil-siHBV X可以有效和特异地抑制HepG 2.2. 15细胞HBV-DNA的复制及HBsAg和HBeAg表达。 相似文献
96.
Nomura H Nishimori H Yasoshima T Hata F Tanaka H Nakajima F Honma T Araya J Kamiguchi K Isomura H Sato N Denno R Hirata K 《Clinical & experimental metastasis》2002,19(5):391-399
To elucidate the mechanisms of metastasis, we established two sublines HPC-1H5 with a highly liver metastatic cell line and
HPC-1P5a with a highly peritoneal disseminating cell line, which were sequentially selected from the parental pancreatic cancer
cell line HPC-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed
genes involved in cancer metastasis by cDNA macroarray. Microscopic findings for the three cell lines were the same. The tumorigenicity,
in vitro growth ability, motile activity, adhesive activity and the production of IL-8 of metastatic sublines were higher than those
of parental HPC-1 cells. Particularly, HPC-1H5 cells showed clearly higher levels of IL-8 expression and tumors of HPC-1H5
cells grew faster and bigger than those of HPC-1P5a cells. In cDNA macroarray analysis of HPC-1H5 cells, 22 genes were up-regulated
and 44 genes were down-regulated compared with parental HPC-1 cells. In HPC-1P5a cells, 9 genes were up-regulated and 28 genes
were down-regulated compared with parental HPC-1 cells. This study provides a demonstration of global gene expression analysis
of pancreatic cancer cells with liver metastasis and peritoneal dissemination. Furthermore, our results provide a new insight
into the study of liver metastasis and peritoneal dissemination of human pancreatic cancer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
97.
Chen BF Chen PJ Jow GM Sablon E Liu CJ Chen DS Kao JH 《Journal of medical virology》2004,74(4):536-542
The clinical relevance of hepatitis B virus (HBV) genotypes has been documented; however, the prevalence of mixed HBV genotype infections in at-risk groups remains controversial. The HBV genotypes were determined in 325 HBV-infected intravenous drug users (IVDU) who were at a greater risk of multiple exposures to different HBV genotypes by using a newly developed line probe assay. The distribution of HBV genotype was as follows: genotype A alone in 2 (0.6%); genotype B alone in 256 (78.8%); genotype C alone in 10 (3.1%); mixed genotype A and B in 18 (5.5%); genotype B and C in 30 (9.2%); genotype B and D in 1 (0.3%); genotype A and C in 1 (0.3%); and mixed infections of genotype A, B, and C in 3 (0.9%). Clonal analysis confirmed further the existence of mixed genotype infection and recombination between different genotypes. Compared with our previous data, the line probe assay seemed more sensitive than polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay in identifying HBV genotype (98.8% vs. 65.0%) and detecting mixed genotype infections (16.3% vs. 0%). In conclusion, the prevalence of mixed HBV infections is substantially higher in IVDU in endemic areas, and the line probe assay is a useful method for rapid genotyping of HBV, with particular reference to the detection of mixed genotype infections. 相似文献
98.
The anticonvulsant drug phenytoin, in less than cytotoxic concentrations, caused significant reductions in Ig secretion by unstimulated or EBV-stimulated normal MNC, as measured by PFC or secretion of Ig into the culture medium. Isotype-specific LBL varied in their sensitivity, the secretion of IgA (1 line) and IgG (3 lines) being reduced by phenytoin near therapeutic concentrations, whereas that of IgM (1 line) was resistant. Six-day exposure of MNC to phenytoin caused no selective depletion of or enrichment for B cells, monocytes or T cell subsets. The results suggest that the reduction in serum Ig levels reported in phenytoin-treated epileptic patients is, at least in part, due to a direct effect of the drug on the B lymphocyte. However, among EBV-activated normal MNC, those secreting IgA were no more sensitive to the drug than those secreting IgG or IgM, and other factors may, therefore, operate to cause the preferential reduction in serum IgA in phenytoin-treated patients. 相似文献
99.
100.
澳门中学生精神信仰的现状研究 总被引:2,自引:0,他引:2
目的考察澳门中学生精神信仰的现状与特点。方法采用中学生精神信仰问卷对1379名澳门中学生的精神信仰进行调查。结果1澳门中学生在一级信仰因素上的均值排列顺序由高到低依次是实用信仰、社会信仰、超自然信仰。在7个二级信仰维度上的均值排列顺序由高到低依次为家庭主义、生命崇拜、国家民族、政治信仰、神灵崇拜、金钱物质、宗教信仰。2女生在宗教信仰和神灵崇拜上的得分显著高于男生。3高三年级学生在金钱物质和国家民族的信仰程度最高,得分高于其他年级。4学生干部在国家民族、政治信仰、生命崇拜和家庭主义上的得分显著高于非学生干部。5学习成绩好的学生和成绩中等的学生在国家民族、政治信仰和家庭主义上的得分显著高于学习成绩差的学生。结论澳门中学生的精神信仰总体上是积极健康向上的。 相似文献