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991.
992.
槟榔(Areca catechu L.)的民族植物学 总被引:3,自引:0,他引:3
本文从民族植物学的观点介绍了我国南方各省嚼槟榔的习俗、历史及演变,分析了这个习俗的形成原因及槟榔的药用价值。作者认为咀嚼槟榔有成瘾性,但是否对人的中枢神经系统有损害,必须进一步研究。作者对这种习俗提出了几点看法和建议,对槟榔的开发利用有重要参考价值。 相似文献
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994.
995.
Kitada H Miyata M Nakamura T Tozawa A Honma W Shimada M Nagata K Sinal CJ Guo GL Gonzalez FJ Yamazoe Y 《The Journal of biological chemistry》2003,278(20):17838-17844
Supplement of 1% lithocholic acid (LCA) in the diet for 5-9 days resulted in elevated levels of the marker for liver damage aspartate aminotransferase and alkaline phosphatase activities in both farnesoid X receptor (FXR)-null and wild-type female mice. The levels were clearly higher in wild-type mice than in FXR-null mice, despite the diminished expression of a bile salt export pump in the latter. Consistent with liver toxicity marker activities, serum and liver levels of bile acids, particularly LCA and taurolithocholic acid, were clearly higher in wild-type mice than in FXR-null mice after 1% LCA supplement. Marked increases in hepatic sulfating activity for LCA (5.5-fold) and hydroxysteroid sulfotransferase (St) 2a (5.8-fold) were detected in liver of FXR-null mice. A 7.4-fold higher 3alpha-sulfated bile acid concentration was observed in bile of FXR-null mice fed an LCA diet compared with that of wild-type mice. Liver St2a content was inversely correlated with levels of alkaline phosphatase. In contrast, microsomal LCA 6beta-hydroxylation was not increased and was in fact lower in FXR-null mice compared in wild-type mice. Clear decreases in mRNA encoding sodium taurocholate cotransporting polypeptide, organic anion transporting polypeptide 1, and liver-specific organic anion transporter-1 function in bile acid import were detected in LCA-fed mice. These transporter levels are higher in FXR-null mice than wild-type mice after 1% LCA supplement. No obvious changes were detected in the Mrp2, Mrp3, and Mrp4 mRNAs. These results indicate hydroxysteroid sulfotransferase-mediated LCA sulfation as a major pathway for protection against LCA-induced liver damage. Furthermore, Northern blot analysis using FXR-null, pregnane X receptor-null, and FXR-pregnane X receptor double-null mice suggests a repressive role of these nuclear receptors on basal St2a expression. 相似文献
996.
C. H. Fu W. W. Guo J. H. Liu X. X. Deng 《In vitro cellular & developmental biology. Plant》2003,39(3):360-364
Summary Somatic hybrid plants were regenerated via electrofusion between leaf-derived protoplasts of ‘Chicken heart’ sweet wampee
(Clausena lansium) and embryogenic protoplasts of ‘Newhall’ navel orange (Citrus sinensis Osbeck). Most of the complete plantlets were formed via mini-grafting. Flow cytometry showed that most of the regenerants
were tetraploids as expected, but unexpectedly three plantlets were triploids. Simple sequence repeat (SSR) analysis of seven
randomly selected tetraploids and the three triploids showed that they had specific fragments from both fusion parents, thereby
confirming their hybridity. Analysis of cytoplasmic genomes using universal primers revealed that their chloroplast DNA (cpDNA)
band pattern was identical to the mesophyll parent, while their mitochondrial genomes were of the navel orange type. According
to the SSR results, the triploids obtained in this study were most likely due to chromosome elimination of ‘Chicken heart’
sweet wampee prior to plant regeneration. 相似文献
997.
亚临床甲亢和甲减发病的实验室调查 总被引:2,自引:1,他引:2
目的 探讨本地区亚临床甲状腺疾病的发病情况。 方法 随机抽样 2 550例健康体检者作甲状腺功能检测 ,以促甲状腺素 ( TSH)水平异常的检出率来判断亚临床甲状腺疾病的发病率。 结果 亚临床甲亢的检出率为5.4 5% ,亚临床甲减的检出率为 6 .98% ;两种疾病 T3、T4、FT3、 FT4 和 TSH的均数比较具有非常显著性差异 ( P <0 .0 1)。 结论 本地区具有亚临床甲状腺疾病的发病现象 ,亚临床甲减的发病率比亚临床甲亢稍高 相似文献
998.
Wei Guo Dong Ren Xiuting Chen Xiang'an Tu Shuai Huang Min Wang Libing Song Xuenong Zou Xinsheng Peng 《Journal of cellular biochemistry》2013,114(7):1606-1615
The principal problem arising from prostate cancer (PCa) is its propensity to metastasize to bones, and it's crucial to understand the mechanism of tumor progression to metastasis in order to develop therapies that may reduce the morbidity and mortality of PCa patients. Although we had identified that microRNA(miR)‐145 could repress bone metastasis of PCa via regulating epithelial–mesenchymal transition (EMT) in previous study, it is still unknown how miR‐145 regulated EMT. In the present study, we constructed a luciferase reporter system and identified HEF1 as a direct target of miR‐145. More importantly, HEF1 was shown to promote migration, invasion and EMT of PC‐3 cells, a human PCa cell line originated from a bone metastatic PCa specimen. And HEF1 was also shown to partially mediate miR‐145 suppression of EMT and invasion. Furthermore, inhibition of HEF1 repressed bone invasion of PC‐3 cells in vivo. Expression of HEF1 was negatively correlated with miR‐145 in primary PCa and bone metastatic specimens, but HEF1 was higher in samples which were more likely to commit to bone metastasis or those with higher free prostate‐specific antigen (fPSA) levels and Gleason scores. Taken together, these findings indicate that HEF1 promotes EMT and bone invasion in prostate cancer by directly targeted by miR‐145, and miR‐145 suppresses EMT and invasion, at least in part, through repressing HEF1. J. Cell. Biochem. 114: 1606–1615, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
999.
Lu Guo Xiaoyan Hu Tongfu Xu Xin Qi Yang Wan Xiaopeng Liu Yali Jiang Lianying Zhang 《Molecular biology reports》2011,38(3):1869-1874
Zinc is an essential nutrient for all organisms, which is involved in the function of numerous key enzymes in metabolism.
Two gene families have been identified involved in zinc homeostasis. ZnT transporters reduce intracellular zinc while Zip
transporters increase intracellular zinc. Previous studies in our laboratory have shown that Zip-1, ZnT-1, Zip-2 and LIV-1
mRNA are associated with zinc level in established human breast cancer in nude mice model. In this study, six zinc transporters:
ZnT-1, ZnT-2, ZnT-4, Zip-1, Zip-8 and Zip-13 were chosen. We aim to determine the relation between zinc transporters and zinc
level in kidney and lung of Wistar rats. Eighteen Wistar rats were randomly divided into three groups: normal group, zinc-deficiency
group and pair-fed group. After 22 days, the rats were killed and organs samples were taken, then zinc transporters mRNA were
detected by RT-PCR. Compared with the normal group, Zip-13 shows an up-regulation (P < 0.05) in zinc-deficiency group both in kidney and lung, and Zip-8 was significantly lower (P < 0.05) in zinc-deficiency group in kidney. 相似文献
1000.
Chang Y Guo David L Brautigan James M Larner 《The Journal of biological chemistry》2002,277(7):4839-4844
Ionizing radiation (IR) is known to activate multiple cell cycle checkpoints that are thought to enhance the ability of cells to respond to DNA damage. Protein phosphatase 2A (PP2A) has been implicated in IR-induced activation of checkpoints; therefore, Jurkat cells were exposed to an activating dose of IR or sham treatment as control, and nuclear extracts were analyzed for PP2A by Mono Q anion exchange chromatography and microcystin affinity chromatography. PP2A exists in eukaryotic cells both as a heterodimer consisting of a 65-kDa scaffolding subunit (A) plus a 36-kDa catalytic subunit (C) and as ABC heterotrimers, containing one of a variety of regulatory (B) subunits. Here we show that IR produces a transient and reversible reduction in the amount of nuclear AB55C heterotrimer without affecting the AB'C heterotrimer or AC heterodimer. In ataxia telangiectasia-mutated (ATM)-deficient cells the amount of nuclear PP2A heterotrimer relative to heterodimer was not reduced by radiation, but the radiation response was restored by transfection of these cells with plasmids encoding ATM. Wortmannin, an inhibitor of kinases such as phosphatidylinositol 3-kinase, also prevented the IR-induced reduction in nuclear PP2A heterotrimer. The changes in nuclear PP2A occurred without a noticeable difference in the carboxyl-terminal methylation of the C subunit, which is known to influence association with B subunits. We conclude a novel ATM-dependent mechanism is regulating association of B55 subunits with nuclear PP2A in response to IR. 相似文献