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931.
Lu M  Zhang Y  Liu YM 《生理科学进展》2007,38(2):159-162
c-Ski/SnoN是由原癌基因c-ski/sno编码的核蛋白,属于Ski家族成员。近年来有研究表明c-Ski/SnoN是TGF-β1/Smad信号通路的重要负性调控因子,通过与Smad蛋白相互作用来抑制TGF-β1靶基因的活化。本文就c-Ski/SnoN对TGF-β1/Smad信号通路的调节作用,以及在肾间质纤维化的发生发展中的作用及机制作一综述。  相似文献   
932.
Xia  Jun  Hao  Xianzhe  Wang  Tangang  Li  Huiqin  Shi  Xiaojuan  Liu  Yongchang  Luo  Honghai 《Journal of Plant Growth Regulation》2023,42(1):319-334
Journal of Plant Growth Regulation - Exogenous substances play an important role in the response of cotton to low-temperature conditions during the germination stage, but little is known about the...  相似文献   
933.
A total of 321 individuals from six cattle populations of four species in a bovine subfamily in China were studied using 12 pairs of microsatellite markers. The genetic diversities within and between populations were calculated. The phylogenetic trees were constructed by (δμ)^2 and DA distances, and the divergence times between populations were estimated by (δμ)^2. Altogether, 144 microsatellite alleles were detected including 24 private alleles and nine shared alleles. Chinese Holstein had the largest number of private alleles (10), whereas Bohai black and Buffalo had the smallest number of private alleles (2). Chinese Holstein showed the highest genetic variability. Its observed number of alleles (Na), mean effective number of alleles (MNA), and mean heterozygosity (He) were 7.7500, 4.9722, and 0.7719, respectively, whereas, the Buffalo and Yak showed low genetic variability. In the phylogenetic trees, Luxi and Holstein grouped first, followed by Bohai and Minnan. Yak branched next and buffalo emerged as the most divergent population from other cattle populations. Luxi and Bohai were estimated to have diverged 0.039-0.105 million years ago (MYA), however, buffalo and Holstein diverged 0.501-1.337 MYA. The divergence time of Yak versus Minnan, Holstein and buffalo was 0.136-0.363, 0.273-0.729, and 0.326-0.600 MYA, respectively.  相似文献   
934.
935.
Liu YJ 《Cell》2001,106(3):259-262
  相似文献   
936.
937.
厌氧条件下,微生物可以通过厌氧代谢产生甲烷(CH4),由此衍生的厌氧消化技术可实现能源的回收利用.产CH4的关键步骤是刺激发酵细菌和产甲烷古菌之间的有效电子转移,电活性微生物可以取代传统的氢/甲酸盐实现直接种间电子传递,其电子传递效率更高.添加导电材料可以促进直接种间电子传递并提高CH4产率,是一种更有效的强化电子传递...  相似文献   
938.
Multiple organs express testin (TES), including the heart. Nevertheless, current understanding of the influence of TES on cardiovascular diseases, especially on cardiac hypertrophy and its etiology, is insufficient. This study investigated the influence of TES on cardiac hypertrophy and its etiology. Murine models with excessive TES expression specific to the heart were constructed with an adeno‐associated virus expression system. Cardiac hypertrophy was stimulated through aortic banding (AB). The severity of cardiac hypertrophy was evaluated through molecular, echocardiographic, pathological, and hemodynamic examination. The findings of our study revealed that TES expression was remarkably suppressed not only in failing human hearts but also in mouse hearts with cardiac hypertrophy. It was discovered that excessive TES expression driven by an adeno‐associated viral vector noticeably inhibited hypertrophy triggered by angiotensin II (Ang II) in cultivated cardiomyocytes from newborn rats. It was also revealed that TES knockdown via AdshTES caused the reverse phenotype in cardiomyocytes. Furthermore, it was proved that excessive TES expression attenuated the ventricular dilation, cardiac hypertrophy, dysfunction, and fibrosis triggered by AB in mice. It was discovered that TES directly interacted with calcineurin and suppressed its downstream signalling pathway. Moreover, the inactivation of calcineurin with cyclosporin A greatly offset the exacerbated hypertrophic response triggered by AB in TES knockdown mice. Overall, the findings of our study suggest that TES serves as a crucial regulator of the hypertrophic reaction by hindering the calcineurin‐dependent pathway in the heart.  相似文献   
939.
目的:观察一次性力竭运动过程及恢复期大鼠纹状体细胞外液中多巴胺(DA)和5-羟色胺(5-HT)及其代谢物浓度的动态变化规律。方法:采用活体微透析结合毛细管电泳.激光诱导技术,连续观察清醒大鼠在一次性力竭运动过程及恢复期纹状体细胞外液中酪氨酸(Tyr)、5-HT、5-羟吲哚乙酸(5-HIAA)、色氨酸(Trp)和DA浓度的动态变化。结果:大鼠纹状体细胞外液中TW、5-HT、5-HIAA水平运动初期均未见显著变化(P〉0.05),运动后期、力竭及恢复期均显著高于安静水平(P〈0.05,P〈0.01);DA、Tyr水平在运动后期、力竭及恢复期显著高于安静水平(P〈0.05,P〈0.01);DA/5-HT运动初期显著升高(P〈0.05,P〈0.01),运动后期出现下降趋势,力竭前15min降至最低点。而恢复期略有回升,但运动后期、力竭及恢复期与安静状态相比均无显著差异。结论:力竭运动过程中大鼠纹状体细胞外液中DA和5-HT的动态变化具有阶段性特征,运动疲劳过程中状体内DA和5-HT两种神经递质的代谢水平均显著增强,而其中以5-HT的作用占优。  相似文献   
940.
To comprehend the diversity and potential control of soil-dwelling fungi, Isaria and Paecilomyces, against the red imported fire ant Solenopsis invicta (Hymenoptera, Formicidae), an investigation was carried out between 2004 and 2008. From 258 soil samples collected from 16 central and southern provinces and cities in China, a total of 171 isolates of the genra Isaria and Paecilomyce were isolated, and the species I. javanicus, P. marquandii and I. fumosoroseus were found more abundant than I. cateniobliquus, P. carneus, P. inflatus and P. lilacinus. Geographic differences of isolating rates were observed as well. Samples from the southern areas had higher fungal isolating rates than those from the central areas. Subsequently, 47 isolates were further tested for pathogencity against the red imported fire ant. All isolates except P115 showed certain pathogenic potential (the mean is 52.3% at 4000 conidiospores/mL) to the ant. I. javanicus was the most effective species with a mean pathogenicity of 80.6%, while pathogenicities of P. marquandii, P. gunni and I. fumosoroseus were 44, 21 and 49%, respectively. Furthermore, the more effective isolates P028 of I. javanicus and P003 of I. fumosoroseus were tested in a virulence experiment. The LD50 values of P028 and P003 against major and miner workers were determined as 412,280 and 854,451 conidiospores/cm2, respectively. Meanwhile, the LT50 values at 1000 conidiospores/cm2 were 7.1 and 6.6 d in isolate P003 and 6.8 and 6.6 d in isolate P028.  相似文献   
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