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51.
将临床收集确诊的40只细小病毒病犬分为黄芪多糖组和常规治疗组,对黄芪多糖是否具有治疗犬细小病毒病的作用进行试验研究,并以犬血常规变化来检验其疗效。结果表明:细小病毒病以2~5月龄犬发病较多,并以肠炎型为主。犬感染细小病毒后白细胞数、红细胞数、血红蛋白含量、红细胞压积均低于正常值范围。黄芪多糖能够升高病犬白细胞数、红细胞数、血红蛋白含量,除红细胞数外,在治疗第6天均恢复到正常水平。黄芪多糖能够升高病犬血清中SOD的活性,治疗第6天与基础值比较差异极显著(P〈0.01);同时能够降低病犬血清中MDA的含量,在治疗第6天与基础值比较差异极显著(P〈0.01),与健康对照组相近。黄芪多糖组治愈率为90%,常规治疗组治愈率为70%。  相似文献   
52.
支持细胞对维持精子形成过程中的微环境起决定作用,它可以通过分泌功能、细胞间连接形成的血睾屏障功能以及吞噬功能等来促进精子的形成过程,其发育异常会导致不同程度的雄性生殖缺陷。基于支持细胞在雄性动物生殖过程中的作用,体外培养高纯度支持细胞可成为研究睾丸两大核心功能-精子发生和性激素分泌功能相关调节机制重要的细胞模型。此外,体外培养睾丸支持细胞也可作为生殖毒理学等新兴热点领域的细胞模型,为评估和研究环境因素对雄性生殖的影响提供便利。因此,作者系统地归纳、总结了目前关于动物支持细胞生物功能的研究及常用的体外分离纯化、培养及鉴定方法,以期为利用动物支持细胞开展雄性生殖领域的研究提供参考。  相似文献   
53.
卢泽艳  邵义祥 《安徽农业科学》2012,40(23):11684-11687
小鼠眼睑发育需要表皮角质形成细胞的增殖、分化、凋亡及迁移的协调作用。表皮角质形成细胞是研究眼睑闭合不全机制重要的细胞模型。表皮角质形成细胞培养时,贴壁差,增殖力低,生活力弱,生长条件要求高,传代次数有限。对近年来表皮角质形成细胞的体外培养方法及其在遗传性眼睑闭合不全研究中的应用进行综述,以期为表皮角质形成细胞的长期培养和研究人类先天性眼睑发育缺陷机制提供参考。  相似文献   
54.
Recent soil‐management practices such as no‐tillage and minimal tillage, when applied to the irrigated rice crop, promote changes in soil composition as a result of anaerobic degradation of organic matter. Several short‐chain organic acids are formed, such as acetic acid. The objective of this work was to determine the effect of calcium (Ca) on plant development under stress by acetic acid toxicity. The experiment was conducted in hydroponics by testing different Ca (0.2, 1.0, and 5.0 mmol L?1) and acetic acid (0 and 2.5 mmol L?1) concentrations. The variables evaluated were the root system morphological parameters (total length, radius, area, dry‐matter weight, and main root growth), shoot parameters (shoot dry matter, plant height), and concentration and total accumulated nitrogen (N), phosphorus (P), potassium (K), Ca, and magnesium (Mg) in the plants. The growth of the root system and the shoots of rice plants were not affected by the addition of Ca to the treatments containing acetic acid.  相似文献   
55.
罗杰  刘玉堂  阚涛  钟清明 《野生动物》2010,31(2):74-76,112
分别采用组织块法和消化法2种接种方法进行银狐垂体细胞系构建研究。在消化法中使用不同浓度的胰蛋白酶来检验效果,同时在原代培养期使用反复差速贴壁法纯化,传代培养期结合使用反复差速贴壁以及两步消化法进行处理。结果表明:组织块法接种后成纤维细胞生长明显,原代培养后期成纤维细胞已为主要细胞;降低胰蛋白酶浓度能降低对细胞损伤,但消化时间会增长;采用消化法接种在抑制成纤维细胞生长方面效果好于组织块法。纯化效果上,结合反复差速贴壁法与两步消化法处理后获得了较好的效果,在原代培养时期能较好去除成纤维细胞并通过持续使用该方法可在传二代后获得较高纯度的细胞,纯度能达到80%以上,能够建立细胞系。  相似文献   
56.
AIM: To detect the expression of miRNA-363 and SOX4 in osteosarcoma tissues and to investigate the effect of miRNA-363 on the viability and apoptosis of human osteosarcoma cell line MG-63.METHODS: Real-time PCR was used to detect the expression level and the relationship of miRNA-363 and SOX4 mRNA in the osteosarcoma tissues and the corresponding paratumorous tissues collected from 63 patients. The expression levels of miRNA-363 and SOX4 in osteosarcoma cell line MG-63 after transfected with miRNA-363 mimics were measured. The cell viability was measured by CCK-8 assay. Flow cytometry was used to monitor the changes of cell cycle and apoptosis. The changes of SOX4 and miRNA-363 expression levels in the MG-63 cells after transfection with SOX4 siRNA or pcDNA/SOX4 was detect by real-time PCR.RESULTS: The expressed level of miRNA-363 was lower, and the expression level of SOX4 was higher in the osteosarcoma tissues than those in the adjacent normal tissues. A significantly negative correlation between the expression levels of miRNA-363 and SOX4 was observed. The expression of miRNA-363 in the MG-63 cells after transfection with miRNA-363 mimics was significantly up-regulated, while the expression of SOX4 in the MG-63 cells was significantly down-regulated, with significant difference as compared with the cells transfected with miRNA-NC and control cells. The viability of MG-63 cells was inhibited, the cell cycle was arrested in G0/G1 phase, and the cell apoptosis was increased by transfection with miRNA-363 mimics. The relative protein expression levels of SOX4 in SOX4 siRNA group and pcNDA/SOX4 group were significantly different from those in negative control group, but the relative expression levels of miRNA-363 had no significant difference. Over-expression of SOX4 restored the viability of the MG-63 cells reduced by miR-363.CONCLUSION: The expression level of miRNA-363 is low in human osteosarcoma tissue. miRNA-363 may inhibits the viability of osteosarcoma cell line MG-63 and promotes cell apoptosis in vitro via inhibiting the SOX4 expression.  相似文献   
57.
Probably the most known and best studied type of plant resistance to pathogenic infections is the hypersensitive response (HR), a form of localized programmed cell death associated with restriction or killing of pathogens that often leads to macroscopically visible localized tissue necrosis. It is generally assumed that cell death and resistance within the HR are physiologically and genetically linked. However, there has been considerable speculation about whether cell death is an absolute requirement for resistance conditioned by the HR. This review discusses the relation of cell death and resistance in the HR, in particular, the importance of cell death in this process. We intend to focus on the increasing amount of research evidence showing that in several plant-pathogen interactions, the two main components of the HR – resistance and cell death – can be physiologically, genetically and temporally uncoupled. In other words, HR should be considered as a combination of resistance and cell death responses, where cell death may be dispensable for plant disease resistance. The varying contribution of these two components (i.e. cell death and resistance) generates an array of defense strategies differing in efficiency. Thus, a very early and rapid defense response seems to contribute to the development of macroscopically symptomless (extreme) resistance, while a moderately early defense response results in resistance with the concomitant development of controlled and limited cell and tissue death (HR). Accordingly, a delayed and failed attempt by the host to elicit resistance responses would result in massively stressed plant tissues (e.g. “systemic HR”) and a partial or almost complete loss of control over pathogen invasion. The dynamic nature of resistance responses in plants implies that resistance can be effective with or without cell death but its outcome and efficiency may depend primarily on the timing and speed of the host response.  相似文献   
58.
The anthracnose fungus Colletotrichum orbiculare invades hosts and establishes biotrophy, later switching to necrotrophy, together with the secretion of an arsenal of effectors. In this review, we describe current progress in the study of pathogen effectors. We identified three virulence-related effectors in C. orbiculare, and revealed part of the strategy for effector-mediated infection, including suppression of immunity triggered by particular effectors. The virulence-related effectors accumulate in a unique interfacial region between C. orbiculare and cucumbers around the neck of primary biotrophic invasive hyphae. We found that the secretion of effectors toward the interface involves exocytosis and SEC22-dependent ER-Golgi traffic.  相似文献   
59.
The hemibiotrophic fungus Colletotrichum orbiculare forms appressoria as infection structures and primarily establishes biotrophic infection in cucumber epidermal cells. Subsequently, it develops necrotrophic infection. In the pre-invasion stage, morphogenesis of appressoria of C. orbiculare is triggered by signals from the plant surface. We found that C. orbiculare PAG1 (Perish-in-the-Absence-of-GYP1), a component of MOR [morphogenesis-related NDR (nuclear Dbf2-related) kinase network] plays an essential role as a key component of the plant-specific signaling pathway and that hydrolysis of cutin by a spore surface esterase creates a cutin monomer that constitutes a key plant-derived signal. Development of the infection structure of C. orbiculare is strictly regulated by the cell cycle and we found that proper regulation of G1/S progression via two-component GAP genes, consisting of BUB2 (Budding-Uninhibited-by-Benomyl-2) and BFA1 (Byr-Four-Alike-1) is essential for the establishment of successful infection. In the post-invasion stage, the establishment of the biotrophic phase of hemibiotrophic fungi is crucial for successful infection. We found that C. orbiculare WHI2 (WHIsky-2), an Saccharomyces cerevisiae stress regulator homolog, is involved in the phase transition from biotrophy to necrotrophy through TOR (Target of Rapamycin) signaling, and is thus essential for full pathogenesis.  相似文献   
60.
AIM:To investigate the effects of serine/threonine kinase 15 (STK15) overexpression on the growth of human esophageal squamous-cell carcinoma (ESCC) cell line KYSE150. METHODS:Recombinant pEGFP-C1-STK15 expression vector was transfected into KYSE150 cells using LipofectamineTM 2000 and the expression of STK15 was detected by fluorescence microscopy and Western blotting. The proliferation of the cells in vitro was measured by MTT assay. The cell cycle distribution and apoptosis were detected by flow cytometry. The proliferation of the cells in vivo was measured by tumorigenicity experiment in nude mice. RESULTS:After recombinant pEGFP-C1-STK15 expression vector was stably transfected into KYSE150 cells, GFP-STK15 fusion protein localized to centrosome and spindle. The STK15-overexpressing colonies were further confirmed by Western blotting. MTT assay showed that the proliferation of the cells in STK15 overexpression group was increased compared with control group (P<0.01). Flow cytometry analysis showed that the percentage of the cells in G0/G1 phase and the cell apoptosis in STK15 overexpression group were decreased compared with control group (P<0.01). The tumorigenicity experiment in nude mice showed that the proliferation of the cells in STK15 overexpression group was increased compared with control group (P<0.01). CONCLUSION: Overexpression of STK15 in human ESCC KYSE150 cells promotes the cell growth in vitro and in vivo, indicating that STK15 may serve as a novel therapeutic target for esophageal carcinoma.  相似文献   
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