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101.
丙烯酰胺对大鼠胚胎神经细胞分化的影响 总被引:3,自引:0,他引:3
用细胞微团培养法研究丙烯酰胺对大鼠胚胎神经细胞分化的影响。结果表明,当细胞培养物中丙烯酰胺浓度大于60μg/ml时,可明显抑制细胞分化,表现为细胞集落数目减少,细胞表面突起和集落间神经纤维束减少,细胞形态改变。其半数分化抑制浓度(ICd50)为75μg/ml,半数存活抑制浓度(ICv50)为90μg/ml,两者较为接近。认为丙烯酰胺对细胞分化的抑制作用可能被其细胞毒作用所掩盖,其致畸作用不可忽视。 相似文献
102.
Michael S NOBES Carol A POLLOCK Pan T HENG Michaelj FIELD 《Nephrology (Carlton, Vic.)》1995,1(4):277-283
Summary: The present studies assessed the effects of manipulating extracellular sodium (Na) concentration and Na transport on cellular hypertrophy and hyperplasia in primary culture of rat proximal tubular cells. A concentration-dependent effect on thymidine incorporation and protein content was observed with cell culture media Na concentration of 130, 140 and 150 mmol/L. This effect was independent of osmolality (matched with mannitol) and no stimulatory effect occurred if choline was substituted for Na. Cells derived from sham-operated (Sx) animals exposed to a higher media concentration of Na (150 vs 140 mmol/L) had both stimulated thymidine incorporation to 186.8 ± 35.41% (P<0.05) and enhanced cell protein content to 134.7 ± 135% (P<0.05). This effect was more pronounced in cell cultures derived from unilaterally nephrectomized (Nx) animals, being 212.8 ± 31.5% (P<0.01) for thymidine incorporation (P<0.05 vs cells from sham-operated animals grown in high Na media) and 114.4 ± 3.2% (P<0.001) for protein content (P=0.11 vs sham-operated cells grown in similar conditions). the addition of 10?4 mmol/L ethylisopropyl amiloride hydrochloride (EIPA) to Nx cells in a normal or high Na concentration media resulted in a decrease in cellular protein content to 82.6 ± 6.8% (P<0.05) and 85.5 ± 0.2% (P<0.0001) compared to respective controls. 10?4 mol/L EIPA in media supplemented with insulin-like growth factor (IGF-1) blocked the proliferative response normally seen in response to this growth factor from 156.6 ± 13.7 to 27.5 ± 3.1% (P<0.0001) compared to control. However, the presence of EIPA did not abrogate the hypertrophic response elicited by IGF-1 (cell protein content 128.1 ± 13.1% of control with IGF-1 vs 124.9 ± 12.5 with IGF-1 and EIPA; P= n.s.). Addition of 10?4 mol/L EIPA to 10% serum derived from either Sx or Nx animals blocked the growth response to the sera, limiting the cellular protein content to 76.6 ± 5.5% (P<0.0001) and 89.7 ± 4.4% (P<0.0001) and thymidine incorporation to quiescent levels of 0.2 ± 0.1% (P<0.0001) and 0.4 ± 0.1% (P<0.0001) compared to respective controls. In summary, rat renal proximal tubular cell growth is influenced by Na concentrations in the cell culture environment and inhibited in the presence of EIPA. This supports a role for altered epithelial transport in the cellular growth response to a number of stimuli. 相似文献
103.
The knee meniscus exhibits extensive spatial variations in native healing capacity, biochemical composition, and cell morphology that suggest the existence of distinct phenotypes for meniscus cells. Constitutive gene expression levels of appropriate extracellular matrix proteins may serve as useful molecular markers of cellular phenotypes; however, relatively little is known of variations in the gene expression for meniscus cells of different regions of the tissue. The objective of the present study was to evaluate constitutive differences between radial inner and outer regions in gene expression for extracellular matrix proteins relevant to the meniscus. A secondary objective was to determine if these region-specific differences in gene expression are maintained after periods of monolayer culture. The innermost regions of the meniscus were found to constitutively express higher mRNA levels for proteins highly expressed in articular cartilage, including aggrecan, type II collagen, and NOS2. In contrast, the outer meniscus was found to contain higher gene expression for proteins associated with fibrous tissues including type I collagen, and the proteases MMP2 and MMP3. Isolated inner and outer meniscus cells maintained these region-specific gene expression patterns for collagens and proteoglycans during short-term monolayer culture. The results provide new information that suggests the utility of constitutive gene expression levels as molecular markers to distinguish tissue and cells of the inner and outer meniscus. 相似文献
104.
恙虫病东方体在无生命培养基内生长的研究 总被引:1,自引:0,他引:1
目的 恙虫病东方体 (Orientiatsutsugamushi;Ot)被认为属专性细胞内寄生。特别是制备大量抗原培养难的问题 ,是近一个世纪以来人们渴望解决的难题。为证实是否能在无生命培养基生长。方法 用Vero -E6个单层组织细胞培养OtJL - 90株与标准Gilliam株 ,在合适时取该培养物接种于Ⅲ号无生命固体培养基培养 ,置 36℃ (± 1℃ )培养 18- 2 4h。结果 可见生长一群无色透明或半透明光滑、湿润、圆形或枫叶样小菌落 ,并产生一种难闻的臭味。两种方法培养物分别做了生物学性状鉴定、形态染色、小白鼠致病力、血清学特异性间接免疫荧光检测。各株Ot经两种培养获得培养物特性基本一致。结论 Ot能在细胞内生长也能在无生命培养基内生长 ,解决了Ot大量抗原培养难的困扰。 相似文献
105.
糖骨康胶囊治疗糖尿病骨质疏松临床研究 总被引:2,自引:0,他引:2
目的:观察糖骨康胶囊对糖尿病骨质疏松的治疗作用。方法:将216例患者,遵照随机、盲法、对照原则分为治疗组144例、对照组72例,其中治疗组给予糖骨康胶囊,对照组给予甘露消渴丸,治疗8w后观察疗效。结果:治疗组显效率为40.0%;总有效率为88.6%。对照组显效率为28.9%,总有效率为82.6%。结论:糖骨康胶囊对2型糖尿病骨质疏松有显著的防治作用。 相似文献
106.
本文对比观察了中西医结合治疗与单纯西药治疗慢性肾炎的临床疗效,结果表明,前者缓解率及总有效率分别为79.8%和92.1%,显著高于对照组(均P<0.01)。治疗组各临床类型及各中医证型的疗效亦均明显高于对照组相对应的各型肾炎(P<0.05~0.01)。治疗组各型肾炎之血液流变学及甲皱微循环改善均较对照组为显著。两组中完全缓解加基本缓解者,该两类检查指标改善极为显著(P<0.05~0.01),而好转及无效者则无明显改善(P>0.05)。提示临床疗效与之密切相关。 相似文献
107.
猕猴桃中药复方制剂对血清SOD及MDA含量的影响 总被引:4,自引:0,他引:4
猕猴桃中药复方制剂系采用猕猴桃汁为基质,配加绞股蓝、丹参等中药的有效成分制成。为了研究它的保健作用,在63例50岁以上、无急性疾病的中、老年人,36例30~49岁健康的青年,32例14~17岁健康的少年中进行试验,10ml每日2次连续服用30天后,中老年人血液SOD显著增高,70岁以上老人平均增高2.8倍,血清MDA明显下降,70岁以上平均下降87.5%。 相似文献
108.
Macrophage-like cells from explant cultures of rat sciatic nerve produce apolipoprotein E 总被引:3,自引:0,他引:3
Apolipoprotein E is synthesized and secreted by degenerating peripheral nerve, but the role of resident endoneurial cells in this process is not clear. To exclude the involvement of nonresident cells, we examined the cellular source of endoneurial apolipoprotein E in explant cultures of rat sciatic nerve. The cellular outgrowth from these explant cultures released apolipoprotein E into the culture medium. The cellular outgrowth contained fibroblasts, Schwann cells, and a population of cells with many phenotypic characteristics of macrophages, including the production of apolipoprotein E. No other cell type in the cultures appeared to contribute to this production. These data suggest that apolipoprotein E is produced by resident endoneurial cells in explant cultures and that these cells are macrophages. 相似文献
109.
110.
大鼠嗅鞘细胞的培养和纯化 总被引:3,自引:0,他引:3
目的 建立一种可行的培养和纯化嗅鞘细胞的方法以对其进行研究。方法 利用显微外科技术 ,从新生大鼠脑中取出嗅球的嗅神经组织 ,去除脑膜和微血管 ,消化后细胞以 1× 10 6个细胞 /ml接种在含有 10 %的DMEM/F12 ( 1∶1)培养液中于体外进行培养 ,利用阿糖胞苷Arac和Thy1.1单抗去除成纤维细胞 ,胰酶传代时通过仔细的监测将星形胶质细胞去掉 ,通过纯化获得大量的嗅鞘细胞。结果 嗅鞘细胞较容易培养 ,其增殖速度较快 ,污染的星形胶质细胞和成纤维细胞可有效地被去除 ,显微镜下嗅鞘细胞有卵圆形的胞体和长的、细的突触 ,为双级或多级的细胞 ;透射电镜显示细胞具有锯齿状的核 ,伴有大块染色体和电子密度的胞浆及散在的纤维。形态学和超微结构显示我们获得了较纯的细胞。结论 所建立的培养方法可行 ,适宜从新生大鼠中获得嗅鞘细胞。 相似文献