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81.
Yehoshua Gozes Douglas E. Brenneman Mati Fridkin Richard Asofsky Illana Gozes 《Brain research》1991,540(1-2):319-321
Vasoactive intestinal peptide (VIP) is a neuropeptide which also interacts with cells of the immune system. The paucity of specific VIP receptor antagonists has hampered studies of possible receptor heterogeneity and of VIP function. To aid in achieving these goals, a new VIP antagonist, a hybrid between neurotensin and VIP, has been synthesized. This peptide interacted with VIP receptors on spinal cord cells with an affinity 10-fold greater than VIP itself. In contrast, 1000-fold higher concentrations of the antagonist were required to displace labeled VIP from its receptor on lymphoid cells as compared to VIP itself, suggesting VIP receptor heterogeneity between immune and spinal cord cells. 相似文献
82.
Summary Nephrolithiasis is presented in 18–40% of patients with primary hyperparathyroidism. Our work suggests that citrate, an inhibitor of calcium salts, could be involved in the presence of renal lithiasis because hyperparathyroid stone formers show less citrate elimination than nonstone formers. 相似文献
83.
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
84.
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
85.
自1977~1988年我院共收治13例原发睾丸恶性淋巴瘤,占同期睾丸恶性肿瘤的11.5%。本病少见,大部分发生在50岁以上。本文50岁以上者10例,约占80%。此病预后差,本文11侧2年内死亡,占85%。5年生存率仅为15%。本文5例术后辅以放、化疗,8例术后单纯化疗,两者生存期无明显差异,故我们认为手术 化疗为本病的首选治疗方案。 相似文献
86.
本文应用单克隆抗体检测33例原发性肺癌病人治疗前后外周血中T淋巴细胞亚群变化。结果提示:肺癌病人外周血中T细胞亚群明显有别于正常人,主要表现为T_H细胞降低和T_S细胞升高以及T_H/T_S比值明显倒置。短期观察结果表明,肺癌病人外周血中T_S细胞持续升高和T_H/T_S比值持续降低者,预后不良。临床检测T细胞亚群变化及它们的动态变化可作为判断宿主抗肿瘤免疫功能状态、病情发展和预后的敏感指标。 相似文献
87.
目的 探讨原发性骨质疏松骨折的治疗方法。方法 对 138例原发性骨质疏松骨折 ,在治疗骨折的同时采用联合用药 ,中西医结合用药及脉冲电磁场进行病因学治疗。结果 138例中 134例获得 8~ 36个月 ,平均 13.5个月的随访 ,按优、良、可、差疗效评定标准 ,优 4 8例 ,良 6 2例 ,可 14例 ,差 6例 ,优良率 85.1% ,另 4例半年后死于其它疾病。结论 原性骨质疏松性骨折必须在进行骨折治疗的同时 ,进行骨质疏松病因学的治疗 ,二者结合才能收到较好的疗效 相似文献
88.
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
89.
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
90.
目的:了解三、四年级小学生心理健康状况,探讨小学生心理健康与家庭环境因素关系。方法:采用小学生心理健康诊断测验(MHT)和家庭环境量表(FES)对柳州市四所小学三、四年级1781名小学生的心理健康状况及其家庭环境进行调查。结果:家庭环境中的亲密度、情感表达、知识性、娱乐性、道德宗教、组织性与心理健康问题因子呈负相关关系;家庭环境中的矛盾性、独立性、成功性、控制性与心理健康问题因子呈正相关关系;多元回归分析发现家庭环境中的亲密度、情感表达、知识性、娱乐性、组织性对三、四年级小学生心理健康有积极影响;家庭环境中的矛盾性、独立性、成功性、道德宗教、控制性对三、四年级小学生心理健康有消极影响。结论:家庭环境对三、四年级小学生心理健康水平有重要影响。 相似文献