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71.
We investigated the distribution of myofibroblasts and CD34-positive stromal cells in normal gallbladder and its pathological conditions (cholecystitis, n=25) using immunohistochemistry and in situ hybridization. In the wall of normal gallbladder, myofibroblasts were generally absent from all layers, but many CD34-positive stromal cells were observed in the connective tissue layer. In chronic cholecystitis with mild perimuscular fibrosis, a small to moderate number of myofibroblasts appeared in the mucosal layer. In chronic cholecystitis with marked perimuscular fibrosis, a small to large number of myofibroblasts appeared predominantly in the connective tissue layer, whereas the number of CD34-positive stromal cells decreased at the same location, although the number of myofibroblasts increased. In chronic cholecystitis with xanthogranulomatous foci, a small to large number of myofibroblasts were observed in the periphery of the xanthogranulomatous reaction and adjacent area. In contrast, CD34-positive stromal cells were completely absent or were limited to the area just around the xanthogranulomatous reaction. Induction of collagen type I and III mRNA was predominantly observed in the cytoplasm of myofibroblasts associated with the marked fibrosis, which consisted primarily of mature collagen fibers, and in the cytoplasm of myofibroblasts around the xanthogranulomatous reaction, respectively. Finally, myofibroblasts were observed in all subtypes. The increased number of myofibroblasts was most prominent in the connective tissue layer of chronic cholecystitis with marked perimuscular fibrosis or in the area adjacent to xanthogranulomatous foci of chronic cholecystitis. Under these conditions, CD34-positive stromal cells tended to disappear from the connective tissue layer, which exhibited an increase in myofibroblasts.  相似文献   
72.
An experiment was conducted to investigate the effect of phytase transgenic corn (PTC) on intestinal microflora, and the fate of transgenic DNA and protein in the digesta and tissues of broilers. A total of 160 1-day-old Arbor Acres commercial male broilers were randomly assigned to 20 cages (8 chicks per cage) with 10 cages (replicates) for each treatment. Birds were fed with a diet containing either PTC (54.0% during 1–21 days and 61.0% during 22–42 days) or non-transgenic isogenic control corn (CC) for a duration of 42 days. There were no significant differences (P>0.05) between birds fed with the PTC diets and those fed with the CC diets in the quantities of aerobic bacteria, anaerobic bacteria, colibacillus and lactobacilli, or microbial diversities in the contents of ileum and cecum. Transgenic phyA2 DNA was not detected, but phyA2 protein was detected in the digesta of duodenum and jejunum of broilers fed with the PTC diets. Both transgenic phyA2 DNA and protein fragments were not found in the digesta of the ileum and rectum, heart, liver, kidney, and breast or thigh muscles of broilers fed with the PTC diets. It was concluded that PTC had no adverse effect on the quantity and diversity of gut microorganisms; Transgenic phyA2 DNA or protein was rapidly degraded in the intestinal tract and was not transferred to the tissues of broilers.  相似文献   
73.
恢复梯度上华中亚热带森林生物多样性、林分因子及功能特性对生物量、生产力的影响 草地群落上进行的控制实验大都发现生物多样性对生态系统功能有显著促进作用。然而,在天然林中,多样性与林分因子、群落功能特性的相对作用大小仍存在争议。本文在森林恢复梯度上,研究这3类因素对生物量和生产力的相对影响。我们在湖北神农架设置了处于不同恢复阶段的24块(600 m2)亚热 带森林样地,计算了林分生物量和生产力。选择5个关键的植物功能性状,并计算了群落的功能多样性(功能丰富度、功能均匀度和功能离散度)和性状的加权平均值(CWM)。使用一般线性模型(GLMs)、变异分离等方法探究林分因子(密度、林龄、群落最大树高等)、功能特性、物种和功能多样性对生物量和生产力的相对重要性。研究结果表明,随着森林恢复,林分生物量和生产力显著增加,群落物种丰富度显著增加,而功能离散度显著降低。变异分离结果表明,多样性对生物量和生产力的单独效应不显著,但可能通过与林分因子和功能特性的协同效应来影响生物量和生产力。总体而言,我们发现林分因子对亚热带森林生物量和生产力的影响最大,功能特性显著影响生产力,但不影响生物量。这些结果说明,在森林经营中,调整林分结构和群落物种特性是提高森林碳储量和固碳潜力的有效途径。  相似文献   
74.
Circulating exosomes delivering microRNAs are involved in the occurrence and development of cardiovascular diseases. How are the circulating exosomes involved in the repair of endothelial injury in acute myocardial infarction (AMI) convalescence (3-7 days) was still not clear. In this study, circulating exosomes from AMI patients (AMI-Exo) and healthy controls (Normal-Exo) were extracted. In vitro and in vivo, our study showed that circulating exosomes protected endothelial cells (HUVECs) from oxidative stress damage; meanwhile, Normal-Exo showed better protective effects. Through the application of related inhibitors, we found that circulating exosomes shuttled between HUVECs via dynamin. Microarry analysis and qRT-PCR of circulating exosomes showed higher expression of miR-193a-5p in Normal-Exo. Our study showed that miR-193a-5p was the key factor on protecting endothelial cells in vitro and in vivo. Bioinformatics analyses found that activin A receptor type I (ACVR1) was the potential downstream target of miR-193a-5p, which was confirmed by ACVR1 expression and dual-luciferase report. Inhibitor of ACVR1 showed similar protective effects as miR-193a-5p. While overexpression of ACVR1 could attenuate protective effects of miR-193a-5p. To sum up, these findings suggest that circulating exosomes could shuttle between cells through dynamin and deliver miR-193a-5p to protect endothelial cells from oxidative stress damage via ACVR1.  相似文献   
75.
中国美利奴(新疆军垦型)绵羊9个微卫星基因座多态性研究   总被引:10,自引:1,他引:10  
赵宗胜  王根林  郭继刚  李大全 《遗传》2006,28(8):939-944
利用PCR技术和复合电泳银染技术检测中国美利奴(新疆军垦型)绵羊第1号染色体上BM6506,BM1824,BM6438, ILSTS004和OarDB6 等5个基因座和第6号染色体上 BM4621,OarHH55,BM143和OarJMP8 等4个基因座,共9个基因座的基因频率(Pi)、个体鉴别力(DP)、杂合度(H)、多态信息含量(PIC)、和非父排除概率(PE)。结果显示:9个微卫星基因座的基因型分布符合Hardy-Weinberg平衡,绵羊中9个微卫星基因座中BM4621 基因座的DP、H、PIC和PE都为最高。9个微卫星基因座的累积个体鉴别力(CDP)为0.99999,累积非父排除能力(CPE)为0.99915。结果显示9个微卫星基因座适用于中国美利奴(新疆军垦型)绵羊的遗传连锁分析、个体识别和亲权鉴定等研究领域。  相似文献   
76.
Guo ZF  Yan ZH  Wang JR  Wei YM  Zheng YL 《Hereditas》2005,142(2005):56-64
The high-molecular-weight (HMW) prolamines subunits and their coding sequences from wheat-related diploid species Crithopsis delileana were investigated. Only one HMW prolamine subunit with the similar electrophoresis mobility to the y-type HMW glutenin subunit of hexaploid wheat was observed in two accessions of C. delileana by SDS-PAGE analyses of the total storage protein fractions. It was confirmed by sequencing and expression analysis that this prolamine subunit was an x-type subunit. The amino acid sequence of this subunit had the similar typical structure to those of x-type HMW glutenin genes previously described in wheat. An in-frame stop codon was found in the coding sequences of y-type prolamine subunits. It was found by specifically extraction of HMW prolamines and sequence analysis that the coding regions of Ky prolamine subunit gene is very likely to be not expressed as a full-length protein. Phylogenetic analysis indicated that the Kx subunit could be clustered together with 1Ax1 subunit by an interior paralleled branch, and Ky subunit (inactive) was most closely related to the 1Ay subunit. The coding sequences of Kx subunit could successfully be expressed in bacterial expression system, and the expressed protein had the same electrophoresis mobility as the Kx subunit from the seed of C. delileana. It was the first time that the HMW prolamines subunits encoded by K genome of C. delileana were characterized.  相似文献   
77.
水稻大粒种质资源和遗传分析   总被引:14,自引:0,他引:14  
谷粒重量是构成产量的三要素之一,对提高水稻产量具有重要意义.本文概述了国内外水稻大粒种质资源的现状,同时对粒重基因遗传分析的研究进展进行了综述.粒重是一个受多基因控制的数量性状,目前定位的粒重数量性状位点至少达89个、精细定位1个粒重基因gw3.1和1个长粒基因Lk-4(t)以及克隆1个粒重基因GS3,并在此基础上讨论了粒重在育种上的应用.  相似文献   
78.
Developmental control of Arabidopsis seed oil biosynthesis   总被引:2,自引:0,他引:2  
Wang H  Guo J  Lambert KN  Lin Y 《Planta》2007,226(3):773-783
  相似文献   
79.
A restoration program for the control of cyanobacterial blooms and the re-establishment of submerged macrophytes was conducted in Meiliang Bay of Lake Taihu since 2003. The effect of this ecological projects on plankton community and water quality, and factors regulating phytoplankton community were investigated in 2005. In general, some improvements of water quality occurred in the ecological restoration region, especially in the region of restoring aquatic macrophytes, where we detected significant reduction of nutrients. However, it seems the abundance of phytoplankton cannot be effectively control by the present ecological engineering. The phytoplankton abundance was high in the target restoration zone. Results of CCA and correlation analysis indicate that the phytoplankton community was mainly controlled by physico-chemical factors. Cyanobacteria species were positively related with pH, temperature, TP and TSS, while negatively related with TN, TN/TP and conductivity. The most discriminant variable was TN/TP, which explained 15% of the total variance of phytoplankton. However, TN was more important for the fluctuation of TN/TP than TP. It suggested that TN may be the ultimate factor controlling the phytoplankton community in Lake Taihu. Variation partitioning analysis showed that the pure contribution of crustacean was low for the variation of phytoplankton, suggesting that top-down control by crustacean zooplankton was weak in Lake Taihu. In general, this study suggested the reduction of nutrient load should be more important than top-down control using zooplankton for the ecosystem restoration in Lake Taihu.  相似文献   
80.
Previous studies have shown that gene therapy with inducible nitric oxide synthase (iNOS) protects against myocardial infarction at 3 days after gene transfer. However, the long-term effects of iNOS gene therapy on myocardial ischemic injury and cardiac function are unknown. To address this issue, we used a recombinant adenovirus 5 (Ad5) vector (Av3) with deletions of the E1, E2a, and E3 regions, which enables long-lasting recombinant gene expression for at least 2 mo due to lack of inflammation. Mice received intramyocardial injections in the left ventricular (LV) anterior wall of Av3/LacZ (LacZ group) or Av3/iNOS (iNOS group); 1 or 2 mo later, they were subjected to myocardial infarction (30-min coronary occlusion followed by 4 h of reperfusion). Cardiac iNOS gene expression was confirmed by immunoblotting and activity assays at 1 and 2 mo after gene transfer. In the iNOS group, infarct size (percentage of risk region) was significantly reduced (P < 0.05) both at 1 mo (24.2 +/- 3.4%, n = 6, vs. 48.0 +/- 3.6%, n = 8, in the LacZ group) and at 2 mo (23.4 +/- 3.1%, n = 8, vs. 36.6 +/- 2.4%, n = 7). The infarct-sparing effects of iNOS gene therapy were as powerful as those observed 24 h after ischemic preconditioning (23.1 +/- 3.4%, n = 10). iNOS gene transfer had no effect on LV function or dimensions up to 8 wk later (echocardiography). These data demonstrate that iNOS gene therapy mediated by the Av3 vector affords long-term (2 mo) cardioprotection without inflammation or adverse functional consequences, a finding that provides a rationale for further preclinical testing of this therapy.  相似文献   
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