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1.
IntroductionGenistein and daidzein (Fig.1 ) ,two majorisoflavonoids in soybeans,were reported to playimportant roles in cancer prevention[1 ,2 ] .Previousstudies demonstrated that genistein and daidzeininhibited the growth of leukemia,breast,colonand prostate cancers[38] .Our earlier studies alsodemonstrated that daidzein enhanced the immunefunction in mice[9,1 0 ] . These functions madegenistein and daidzein promising candidates forcancer prevention. However,it is usually themetastatic disse…  相似文献   
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IntroductionIn recent years,a great deal of attention hasfocused on finding potential anti- tumor agentsfrom natural sources[14 ] .A vast number ofpromising candidate molecules,especiallycomponents extracted from plants,have beenevaluated[59] .  Herbs have a long history of use as Chinesetraditional medicine.Caesalpinia minax (C.minax) is a wild plantin Yunnan Province,China.The high level of ultraviolet radiation in thistropical province causes widespread skin diseases inthis area.Extract…  相似文献   
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Calreticulin is a unique calcium-binding protein with multiple functions mostly located in the sarcoplasmic/endoplasmic reticulum. A large amount of calcium is absorbed from the medium and transported to mineralization sites during biomineralization in pearl oyster. This paper describes the cloning of the full-length cDNA of calreticulin from Pinctada fucata, namely PCRT. PCRT encodes a deduced 414-amino acid protein, which includes a predicted 17- amino acid signal peptide and an endoplasmic reticulum retrieval sequence HDEL. The protein shows 63%-76% sequence identity and shares some common characteristics with calreticulins from other species. Semi-quantitative RT-PCR indicates that PCRT is ubiquitously expressed in all tissues tested with the highest expression in the hemolymph and the mantle. In situ hybridization analysis of PCRT in the mantle showed strong signals in the inner fold, the inner side of middle fold, and the inner side of outer fold of the mantle epithelium, All these results suggest PCRT might be involved in Ca^2+ transport and storage during oyster biomineralization.  相似文献   
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碳纤维加固低配箍混凝土梁板柱节点的抗震试验   总被引:18,自引:1,他引:18  
简要介绍了五个用碳纤维加固的混凝土低配箍梁板柱节点低周反复试验的情况 ,对试验结果进行了分析 ,发现加固后的节点极限承载力和抗震性能都有大幅度的提高 ,各项性能指标都达到并超过了我国现行抗震规范的要求 ,因此碳纤维加固混凝土节点技术是一个值得进一步深入研究的课题 .  相似文献   
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Alkaline phosphatase from Pinctada fucata was inactivated by o-phthalaldehyde (OPA). The inactivation followed pseudo first-order kinetics with a second rate constant of 0.167 (mmol/L)^-1·min^-1 at pH 7.5 and 25℃. A Tsou's plot analysis showed that inactivation occurred upon formation of one isoindole group. The OPA-modified enzyme lost the ability to bind with the specific affinity column and the presence of substrates or competitive inhibitors protected the enzyme from inactivation. The results revealed that the OPA-reaction site was at the enzyme substrate binding site. Prior modification of the enzyme by lysine or histidine specific reagent abolished formation of the isoindole derivatives, suggesting that lysine and histidine residues were involved in the OPA-induced inactivation. Taken together, OPA inactivated the alkaline phosphatase from Pinctada fucata by cross-linking lysine and histidine residues at the active site and formed an isoindole group at the substrate binding site of the enzyme.  相似文献   
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IntroductionGonadotropin- releasing hormone ( Gn RH) ,whichis synthesized in the brain and secreted into theanterior pituitary,plays a central role in thecontrol of mammalian reproduction[1,2 ] .Gn RH andGn RH m RNA have been reported to exist in non-hypothalamic tissues such as ovary[3,4 ] ,breast[5] ,testes,and placenta[6] .The Gn RH binding siteand its m RNA have also been found inextrapituitary tissues,including gonads andplacenta[7] .These findings indicate the biologicalsignifican…  相似文献   
8.
IntroductionThe progression of a tumor cell from benigndelimited proliferation to malignant and metastaticgrowth is the majorcause of poorclinical outcomesof cancer therapy.Angiogenesis in the host is acharacteristic phenomenon of most malignanttumors.With adequate blood supply,tumor cellswill not only grow,but also acquire metastaticpotential[1] . This process may involve theproduction of tumor- derived mediators ofendothelial cell migration and proliferation throughenzymes ( such as collagen…  相似文献   
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二齿蝗属(Bidentacris Zheng,1982)是网翅蝗科(Arcypteridae)中的一个小属,建立于1982年(郑哲民,1982),该属的种类分布于我国的西南和南部地区。最近,我们在整理本属标本时,发现有三个新种及两个新组合,现将研究结果报导如下。模式标本保存于陕西师范大学生物系蝗虫研究室。  相似文献   
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导弹射击精度鉴定中Bayes方法的运用   总被引:6,自引:2,他引:4  
以导弹射击精度鉴定问题为对象,研究了运用Bayes理论从仿真试验数据中提取有用信息,从而实现在少量现场试验样本情况下有效完成试验鉴定任务的方法。在简要介绍Bayes理论基本思想的基础上,着重介绍了运用自动(Bootstrap)法从仿真试验结果中获取验前信息的基本思想和一般方法。以及在获得前信息后结合现场试验样本进行导弹射击精度鉴定的方法;最后本文还指出了将Bayes方法应用于具体工程实践时必须考虑的一些问题。  相似文献   
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