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991.
大鼠膝骨关节炎滑膜细胞原代培养   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:建立原代培养膝骨关节炎大鼠滑膜细胞的方法。方法:取膝骨关节炎大鼠膝关节滑膜组织,用酶消化法消化、分离细胞,用DMEM培养液进行培养并传代,观察滑膜细胞生长状况、并用细胞形态学及细胞免疫化学鉴定。结果:用酶消化法培养膝骨关节炎滑膜细胞,方法简单、成功率高、细胞形态典型。结论:单一的胶原酶消化法是一种有效的滑膜细胞原代培养的方法,可以满足一般实验需求。  相似文献   
992.
通过单因素试验分析不同碳源、氮源、无机盐对(Sphingomonas paucimobilisFJAT-5627)产胶量的影响,确定最适碳源、氮源、无机盐,并在单因素筛选试验的基础上,利用Box-Benhnken设计和响应面分析法对碳源、氮源和无机盐进行优化,得到少动鞘脂单胞菌产生结冷肢发酵培养基最佳优化组合.实验结果表明,少动鞘脂单胞菌产胶量发酵最适碳源、氮源和无机盐分别为淀粉、豆饼粉和KH2PO4.响应面法得到产胶量(Y)与碳源淀粉(x1)、氮源豆饼粉(x2)和无机盐KH2PO4(x3)的回归方程为:Y=13.87+0.54x1+0.22x2-0.42x3-3.26x12-1.85x22-1.51x32+0.053x1x2+0.067x1x3+0.4x2x3.优化培养基组合为:淀粉浓度为30g/L,豆饼粉浓度为5 g/L,KH2PO4的浓度为0.7g/L,且此组合下少动鞘脂假单胞发酵得到结冷胶可达23.87g/L.  相似文献   
993.
目的探索和建立东方田鼠皮肤成纤维细胞体外分离、培养的技术方法并观察其生物学特性。方法采用含10%小牛血清的Dulbecco改良Eagle培养液(DMEM)和1640两种培养体系,运用组织块贴壁法和胰酶消化法,分别对出生后1、3 d和5 d的东方田鼠乳鼠皮肤成纤维细胞进行原代分离、培养。苏木素-伊红染色及倒置相差显微镜下观察成纤维细胞形态和生长特性。结果 0.25%胰酶消化分离出生后1 d和3 d东方田鼠乳鼠皮肤较出生后5 d组织可获得较多数量细胞,成纤维细胞在体外快速贴壁生长,一般6~7 d长满培养瓶,细胞纯度高,HE染色细胞呈长梭形,胞核明显;DMEM和1640两种培养液均可用于东方田鼠皮肤成纤维细胞的培养,但细胞传代后生长趋缓,只可传代2~3次。本实验运用组织块贴壁法未能培养出皮肤成纤维细胞。结论确定了有效分离东方田鼠皮肤成纤维细胞的日龄和方法,为进一步深入研究提供了技术方法和操作依据。  相似文献   
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995.
There has long been controversy concerning the relative importance of environment and ancestry in determining the characteristics of living creatures including members of the human species. At the beginning of the present century most biologists and anthropologists seem to have assumed that environment had little or no effect upon our bodily traits. We inherited them. The studies of Franz Boas on Changes in Bodily Form of Descendants of Immigrants cast doubts upon this assumption, and provoked considerable resentment. Since 1911, however, quite a few scholars have confirmed and elaborated upon the findings of Boas. At the same time, many other studies have demonstrated secular changes bodily size and shape within quite a few different populations. The idea of bodily plasticity has therefore, by this decade, become quite acceptable. This paper recounts the historical sequence of events leading to the change in anthropological assumptions, mentioning the scholars whose work contributed to this Important advance in scientific understanding.  相似文献   
996.
These experiments were done to determine whether the culture medium used for the spontaneous maturation of mouse oocytes can affect the subsequent capacity of the ova to become fertilized and complete preimplantation development in vitro and development to live young. Oocytes obtained from antral follicles of gonadotropin-primed immature mice underwent spontaneous maturation in control medium, i.e. Eagle's Minimum Essential Medium (MEM) supplemented with 5% fetal bovine serum, or in one of eight different media which were also supplemented with serum. All of the ova were fertilized in Whitten's medium and were assessed for cleavage to the 2-cell stage and for further preimplantation development to blastocysts during culture in Whitten's medium. Three of the eight media used for oocyte maturation improved the capacity of the ova to develop to the blastocyst stage when compared with the control: Waymouth MB 752/1, MEM with non-essential amino acids, and MEM Alpha; Waymouth medium promoted the highest frequency of development of ova to the blastocyst stage. Moreover, the blastocysts derived from oocytes that matured in Waymouth medium contained more cells than blastocysts derived from oocytes that matured in control medium. Although BGJb medium promoted the cleavage of eggs to the 2-cell stage when present during oocyte maturation, it had a detrimental effect on their subsequent preimplantation developmental capacity. Following transfer to foster mothers, more 2-cell stage embryos developed to live young after oocyte maturation in Waymouth medium (21%) than in control medium (13%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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998.
999.
The cytochrome P450-mediated synthesis of dopamine from tyramine has been shown in vitro. The aim of the present study was to demonstrate the ability of rat cytochrome P450 (CYP) 2D to synthesize dopamine from tyramine in the brain in vivo. We employed two experimental models using reserpinized rats with a blockade of the classical pathway of dopamine synthesis from tyrosine. Model A estimated dopamine production from endogenous tyramine in brain structures in vivo (ex vivo measurement of a tissue dopamine level), while Model B measured extracellular dopamine produced from exogenous tyramine (an in vivo microdialysis). In Model A, quinine (a CYP2D inhibitor) given intraperitoneally caused a significant decrease in dopamine level in the striatum and nucleus accumbens and tended to fall in the substantia nigra and frontal cortex. In Model B, an increase in extracellular dopamine level was observed after tyramine given intrastructurally (the striatum). After joint administration of tyramine and quinine, the amount of the dopamine formed was significantly lower compared to the group receiving tyramine only. The results of the two complementary experimental models indicate that the hydroxylation of tyramine to dopamine may take place in rat brain in vivo, and that CYP2D catalyzes this reaction.  相似文献   
1000.
目的:探索牛肠激酶催化亚基工程菌高效表达的培养条件。方法:牛肠激酶催化亚基基因的初步表达,筛选构建工程菌,从以下方面入手优化培养条件:培养基的组成、摇瓶发酵培养条件、培养基的PH、种龄、接种量、培养时间等,并且通过Western Blotting和SDS-PAGE等鉴定不同条件下的实验结果,从而确定最佳培养条件。结果:通过鉴定实验结果,从不同种平行培养条件中选择产量最高的培养条件,作为最优培养条件。结论:成功地探索并鉴定了工程菌的适宜培养条件。  相似文献   
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