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991.
Jianbo Xiao Tingting Chen Longsheng Chen Fan Yang 《Journal of inorganic biochemistry》2010,104(11):1148-201
Baicalein and genistein were studied for the affinities for human serum albumin (HSA) in the presence and absence of three CdTe quantum dots (QDs) with different sizes. Three typical CdTe QDs with maximum emissions of 535 nm (green-emitting, G-QDs), 598 nm (yellow-emitting, Y-QDs), and 654 nm (red-emitting, R-QDs) were tested. The fluorescence intensities of HSA decreased remarkably with increasing concentration of QDs. Baicalein resulted in an obvious blue-shift of the λem of HSA from 340 to 334 nm. However, the extents of blue-shifts induced by baicalein and genistein in the presence of QDs were much bigger than that in the absence of QDs. The quenching process of baicalein for HSA was easily affected by the QDs size than that of genistein. QDs increased the quenching constant from 136.97% to 162.24% for baicalein. However, QDs only increased the quenching constants from 20.56% to 32.23% for genistein. G-QDs, Y-QDs, and R-QDs increased the affinities of baicalein for HSA about 3.02%, 6.38% and 9.40%. G-QDs, Y-QDs, and R-QDs increased the affinities of genistein for HSA about 2.56%, 13.46% and 19.44%. The binding affinities of baicalein and genistein for HSA increased with increasing QDs size. 相似文献
992.
993.
Haiyan Wei Xuhua Mi Ling Ji Lichuan Yang Qingjie Xia Yuquan Wei Isamu Miyamori ChunYuan Fan 《Biochemistry. Biokhimii?a》2010,75(3):304-309
In this study, we focused on the relationship between aldosterone and NOX1 expression in vascular smooth muscle cells (VSMCs). For the first time, with the use of specific inhibitors of protein kinase
C (PKC), we report that PKCδ mediates upregulation of NOX1 induced by 10 nM aldosterone in cultured VSMCs. Participation of PKC in the mediation of NOX1 regulation was further confirmed by the effect of diacylglycerol, a PKC agonist, on the NOX1 RNA in A7r5 cells with Northern blot analysis. To establish cause and effect, we next silenced the PKCδ gene partly by RNA
interference and found knockdown of PKCδ gene attenuated aldosterone-induced NOX1 expression, generation of superoxide, as well as protein synthesis in VSMCs. Taken together, these data indicated PKCδ might
mediate aldosterone-dependent NOX1 upregulation in VSMCs. In addition, we showed that the cascade from aldosterone to PKCδ activation had the participation
of the mineralocorticoid receptor. 相似文献
994.
Mae Responte YiFan Chiu Po Peng Rafe M. Brown ChiaYen Dai YongChao Su 《Ecology and evolution》2021,11(16):11241
Oceanic islands are unique geographic systems that promote local adaptations and allopatric speciation in many of their highly endemic taxa. This is a common case in the Philippine Archipelago, where numerous unrelated taxa on islands have been inferred to have diversified in isolation. However, few cases have been reported in invertebrates especially among parasitic organisms. Here, we tested for biogeographical structure in novel populations of the “generalist" kleptoparasitic spider, Argyrodes lanyuensis Yoshida, Tso & Severinghaus, 1998 in the Philippines. Results showed that, in addition to Orchid/Lanyu Island, this species has a wide geographic distribution in the Philippine Archipelago. The estimated divergence time of this lineage using the mitochondrial cytochrome oxidase 1 (mt‐CO1) suggests that this species diverged ca 3.12 MYA, during the Pliocene. Two reciprocal monophyletic clades were elucidated in A. lanyuensis, but with limited differentiation across Pleistocene Aggregate Island Complex (PAIC) boundaries and modern‐day islands. However, in our analyses of morphological variation, we identified two phenotypically differentiated units in males (Orchid Island, Taiwan + Luzon, Philippine PAIC populations vs. Palawan + West Visayan + Mindanao PAIC populations). We infer that this species diverged in the southern portion of the Philippine Archipelago and only recently colonized Orchid Island. Our study provides new information on the extensive distribution of A. lanyuensis outside Orchid Island, Taiwan, but we documented a very limited geographically associated genetic variation. Our study points to behavioral phenomena such as foraging behavior as essential contributor to the evolutionary process of species diversification, in contrast to the traditionally invoked geographic drivers of divergence. 相似文献
995.
996.
六种检测猪瘟病毒方法的比较 总被引:1,自引:0,他引:1
【目的】本研究旨在比较6种检测猪瘟病毒方法的优缺点。【方法】应用病毒分离、胶体金免疫层析试纸条、抗原捕捉ELISA、反转录-聚合酶链式反应(RT-PCR)、TaqMan荧光定量RT-PCR(RT-qPCR)和反转录-环介导等温扩增方法(RT-LAMP)等6种方法,分别对50份疑似猪瘟病料中的猪瘟病毒(Classical swine fevervirus,CSFV)进行检测。【结果】结果表明:RT-qPCR和RT-LAMP方法检出阳性样品数为13份,RT-PCR为11份,病毒分离为10份,抗原捕捉ELISA为9份,胶体金试纸条为8份;6种方法均检测为阳性8份,均为阴性37份。【结论】结果提示,在对猪瘟病毒进行检测时,RT-qPCR、RT-LAMP和RT-PCR由于其灵敏性高,可作为首选检测方法,但操作时需要避免假阳性的出现;病毒分离方法虽然操作繁琐,但结果准确,是确诊猪瘟必不可少的检测方法;抗原捕捉ELISA和胶体金试纸条检测时间较短,由于其敏感性较低所限,主要用于对畜群进行检测,不适合个体检测。 相似文献
997.
998.
用盆栽普通烟草幼苗为材料,以简化的植物组织培养实验步骤为基础,设计不同的培养条件,探究了温度和光照对试管苗生长的影响,发现光温适宜的培养室中培养的再生植株高度较低,叶片绿色;而高温弱光下培养的再生植株较高,叶片黄绿色。试管苗的这些生长差异明显与温度的高低和光照的强弱有关。本文介绍的实验方法也可以用于探究pH、植物激素、培养基的类型等对试管苗生长的影响。 相似文献
999.
肝炎后肝硬化患者肝癌发生的保护因素与危险因素研究 总被引:1,自引:0,他引:1
目的:通过回顾性病例对照研究,探讨多种因素在病毒性肝炎后肝化门静脉高压症患者HCC发生过程中的作用以及脾切除是否抑制了肝癌的发生进程。方法:收集第四军医大学西京医院病案统计室检索2002年1月~2008年12月之间出院诊断为病毒性肝炎后(HBV/HCV)肝硬化门脉高压的病例2300余例,收集所有病例的一般资料,临床及实验室检查数据,影象学检查结果,以及在治疗过程中的脾切除手术史。采用病例对照,按年龄、性别两个指标进行1:1配对,根据研究对象是否合并HCC将其分为合并HCC组(组1),未合并HCC组(组2),采用SPSS17.0进行单因素分析及多因素logistic回归分析。结果:描述性统计结果显示,两组的ALB、AST、TP、ALP、GGT等差异有统计学意义(P<0.05),而PLT、ALT、TBIL等在两组间差异无统计学意义(P>0.05)。将单因素分析有意义的研究因素纳入多因素logistic回归方程得知,AST、ALP、GGT异常升高增加了肝癌发生的危险性,而行脾切除和门奇断流术明显降低了肝癌发生的危险性,仅为无手术患者肝癌发生危险性的57.1%(OR:0.571,95%CI:0.394~0.825)。... 相似文献
1000.
目的:比较连续性血液净化(continuous blood purification,CBP)和血液透析(haemodialysis,HD)治疗尿毒症脑病的疗效.方法:70例尿毒症脑病(uremic encephalopathy,UE)患者随机分成连续性血液净化(CBP)组(n=35)和血液透析(HD)组(n=35),分别给予相应治疗.观察缓解率、平均动脉压、肾功能、电解质及血气指标等.结果:1周缓解率分别为100%(CBP组)和65.7%(HD组)(P<0.05);两组的BUN,Scr,K+,Na+,Cl-和β2-MG均显著降低(P<0.05),但治疗后CBP组的BUN,Scr和β2-MG显著低于HD组(P<0.05);CBP组的HC03-和pH较治疗前显著降低(P<0.05),而HD组中HC03-和pH治疗前后无显著改变(P>0.05).CBP组治疗前后平均动脉压变化无统计学差异(P>0.05),HD组低血压发生率为13.7%,高血压发生率为15.4%.结论:CBP治疗能很好清除BUN、Scr和β2-MG,纠正电解质及酸碱紊乱,维持患者血液动力学,具有较好的临床疗效. 相似文献