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71.
AIM:To investigate the effect of tea-polyphenols (TP) on the activation of NF-κB and the expression of TGF-β1 mRNA in THP-1 cells (a human acute monocytic leukemia cell line). METHODS:THP-1 cells were incubated with the different concentrations of TP, VLDL, LDL or ox-LDL. In the THP-1 cellls, the nuclear malposition rate of NF-κB was detected with immunohistochemistry technique, the positive index of the TGF-β1 mRNA expression was detected by hybridization in situ, and accumulation of total cholesterol (TC) in cells incubated with 0.4-40 μg/L TP was determined with oxidase assay. RESULTS:The nuclear malposition rate of NF-κB, the positive index of the TGF-β1 mRNA expression and TC in THP-1 cells incubated with 0.4-40 μg/L of TP were lower than those with 0 μg/L of TP in TP-V group, TP-L group and TP-O (P<0.05). The differences of these markers in THP-1 cells incubated with more than 40 μg/L TP in TP-V group, TP-L group and TP-O were not statistically significant, compared with TP-C group (P>0.05). CONCLUSION:TP inhibited the activation of NF-κB, the expression of TGF-β1 mRNA and the foam cell formation in the mono-macrophage. 相似文献
72.
Accomodation of important sources of uncertainty in ecological models is essential to realistically predicting ecological processes. The purpose of this project is to develop a robust methodology for modeling natural processes on a landscape while accounting for the variability in a process by utilizing environmental and spatial random effects. A hierarchical Bayesian framework has allowed the simultaneous integration of these effects. This framework naturally assumes variables to be random and the posterior distribution of the model provides probabilistic information about the process. Two species in the genus Desmodium were used as examples to illustrate the utility of the model in Southeast Missouri, USA. In addition, two validation techniques were applied to evaluate the qualitative and quantitative characteristics of the predictions.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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番石榴果实发育的初步研究 总被引:7,自引:0,他引:7
以东山月拔和二十一世纪这2个品种为试材,研究了番石榴(Psidium guajava L)果实的发育动态规律。结果表明:番石榴的果实发育呈现双“S”型;果实重量和果核重量的发育呈显著的正相关;推测果实发育后期为进行果实产期调控的关键时期;建议以果实发育的直径大小以及果实转蒂下垂作为确定进行产期调控的田间依据。 相似文献
77.
以红富士苹果果实为试材,在盛花后30d以内,分3次向幼果中引入EGTA和LaCl3,研究了两种钙的抑制剂对果实细胞超微结构和果实生长的影响。结果表明,EGTA主要是在盛花后20d以前影响果肉细胞形态建成,导致细胞扭曲变形;而La3+是在盛花后20d以后,细胞开始扭曲变形,盛花后10d,质体上开始出现淀粉粒,盛花后30d,质体上淀粉粒明显增多。两种抑制剂对幼果发育有不同程度的影响。LaCl3处理,对幼果发育有抑制作用,其中,花后20d处理,抑制效应最强。花后20dEGTA处理,对果实的横径生长有一定的促进作用,其它两次处理,则表现出对幼果生长的抑制效应。 相似文献
78.
The major role of DNA polymerase β was thought to be limited in its involvement in short patch base excision repair by removing 5’-deoxyribose phosphate and base insertion. However, the recent researches indicate that polymerase β might take part in a wide spectrum of DNA metabolism reactions, including long patch base excision repair, DNA replication, recombination, meiosis and transleisional DNA synthesis. Because of its wide and important cellular function, an inappropriate intracellular polymerase β level might be associated with genomic instability. Down-regulation or mutation of polymerase β is mutagenic due to deficient in DNA repair, while overexpression of this error-prone β polymerase might perturb the normal function of other accurate polymerases and cause genomic instability as well. 相似文献
79.
SHANG Zhan-ping HOU Zhong-chi ZHU Shi-gong JI Guo-yi WANG Jian-chun ZHAO Wan 《园艺学报》2002,18(12):1521-1523
AIM: To investigate the activity of interleukin-1β converting enzyme in transplanted intracerebral rat gliomas under angiotensin II-induced hypertension chemotherapy. METHODS: The brain tumor model was produced in Wistar rats by stereotaxic inoculation of C6 glioma cells (1×1012 /L). Tumor-bearing rats were treated with carmustine, teniposide and lisplatin (chemotherapy) during angiotensin II-induced hypertension. Then, the survival time of tumor-bearing rats, tumor blood flow, the concentration of drug, volume of gliomas and the activity of interleukin-1β converting enzyme in glioma were examined.RESULTS: The survival time of tumor-bearing rats was significantly longer in chemotherapy with angiotensin II-induced hypertension group than that of chemotherapy alone. In addition, regional tumor blood flow, the concentration of chemotherapeutic drug and the activity of interleukin -1β converting enzyme in transplanted rat gliomas were increased, while the volume of gliomas was decreased in hypertention chemotherapy group compared with chemotherapy alone. CONCLUSION: Chemotherapy with angiotensin II-induced hypertension has a enhancing effect on chemotherapy for improving the drug delivery to tumor tissue by a increased tumor blood flow and enhancing activity of interleukin -1β converting enzyme. 相似文献
80.
苹果果实日灼人工诱导技术及阈值温度研究 总被引:10,自引:3,他引:10
使用自制的日灼诱导设备,在无风或微风的晴天对活体果实进行田间日灼诱导,通过改变诱导室内的气温来控制和调节果面温度,从而确定了不同苹果品种果实发生日灼的阈值温度。试验证明: 自制的诱导设备运行平稳,诱导期间可保持果温基本稳定,大多数情况下,处理期间果面平均温度与实际设定温度的差异小于0.12℃ ,温度变化幅度一般小于±0.5℃ 。本试验所测定的9个苹果品种日灼阈值温度为(45.9±0.5)℃ (48.5±0.5)℃。光照对日灼发生有重要影响,即使在同样的阈值温度下,有光的处理果实发生日灼,而无光的处理则不发生日灼。 相似文献