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91.
H. Iwata A. Matsuyama N. Okumura S. Yoshida Y. Lee K. Imaizumi S. Shiosaka 《Brain research》1991,550(2):329-332
We examined the localization of basic fibroblast growth factor (basic FGF) in the adult rat brain by immunohistochemical and Western blotting analysis using a specific antibody against a synthetic basic FGF fragment (N-terminal 12 residues). The antibody did not cross-react with acidic FGF. Basic FGF-like immunoreactivity was located exclusively in the neuronal elements and had very heterogenous distribution. Immunoreactive cell bodies were observed in the paraventricular, supraoptic and circular nuclei of the hypothalamus. Numerous immunoreactive neuronal processes originating from these basic FGF-positive cells extended lateroventrally and then caudally to the internal layer of the median eminence. In addition, the neurohypophysis contained a significant number of basic FGF-like immunoreactive fibers. Western-blotting analysis revealed that the hypothalamus and the hypophysis contained a main band of basic FGF immunoreactive with an apparent molecular weight of 17 kDa. These results show that the hypothalamo-hypophyseal neuroendocrine pathway contains basic FGF. 相似文献
92.
目的探讨妊高征(PIH)合并胎儿宫内发育迟缓(IUGR)时胎盘病理改变与胎盘组织中血管细胞粘附分子-1(VCAM-1)表达水平变化的关系。方法选取本院2001年1~9月分娩的妊高征合并IUGR患者(实验组)胎盘30例、单纯IUGR(IUGR组)28例、单纯PIH(PIH组)25例、正常妊娠(正常妊娠组)30例,常规HE染色及PAS染色,观察胎盘形态学变化。利用免疫组化方法对胎盘组织切片染色,观察子宫蜕膜层中螺旋动脉、绒毛组织滋养细胞及绒毛中毛细血管的VCAM-1表达。结果实验组中22例(73.33%)胎盘有明显病理改变,有病理改变的胎盘蜕膜组织内血管内皮细胞及胎盘绒毛毛细血管内皮VCAM-1的表达显著高于无病理改变者(P<0.001);而绒毛上皮组织滋养层细胞VCAM-1的表达则显著低于无病理改变者(P=0.019)。结论妊高征合并IUGR时胎盘发生了明显的病理改变,这种病理改变与胎盘中VCAM-1的异常表达密切相关。 相似文献
93.
Biochemical and ultrastructural alterations produced by miconazole and econazole in Trypanosoma cruzi 总被引:6,自引:0,他引:6
R Docampo S N Moreno J F Turrens A M Katzin S M Gonzalez-Cappa A O Stoppani 《Molecular and biochemical parasitology》1981,3(3):169-180
Miconazole and econazole, two fungicide imidazole derivatives, completely inhibited growth of Trypanosoma cruzi (Tulahuen strain) at concentrations of about 20 muM. Culturing of T. cruzi in the presence of lower doses of imidazole derivatives produced: decrease of 5,7-diene sterol content in epimastigotes (including ergosterol); disappearance of the nuclear chromatin, vacuolization and decrease in the electron density of the cytoplasm; selective surface alterations as revealed by an increased response to wheat-germ- and phytohemagglutinin. At variance with the effect of miconazole on Candida (De Nollin et al. (1977) Antimicrobial. Agents Chemother. 11, 500-513), miconazole and econazole, under the experimental conditions used, did not increase the rate of hydrogen peroxide generation by T. cruzi. 相似文献
94.
95.
96.
Guidance of dopaminergic neuritic growth by immature astrocytes in organotypic cultures of rat fetal ventral mesencephalon. 总被引:3,自引:0,他引:3
Astrocytes, with their many functions in producing and controlling the environment in the brain, are of great interest when it comes to studying regeneration after injury and neurodegenerative diseases such as in grafting in Parkinson's disease. This study was performed to investigate astrocytic guidance of growth derived from dopaminergic neurons using organotypic cultures of rat fetal ventral mesencephalon. Primary cultures were studied at different time points starting from 3 days up to 28 days. Cultures were treated with either interleukin-1 beta (IL-1 beta), which has stimulating effects on astrocytic proliferation, or the astrocytic inhibitor cytosine arabinoside (Ara-C). Tyrosine hydroxylase (TH)-immunohistochemistry was used to visualize dopaminergic neurons, and antibodies against glial fibrillary acidic protein (GFAP) and S100 beta were used to label astrocytes. The results revealed that a robust TH-positive nerve fiber production was seen already at 3 days in vitro. These neurites had disappeared by 5 days. This early nerve fiber outgrowth was not guided by direct interactions with glial cells. Later, at 7 days in vitro, a second wave of TH-positive neuritic outgrowth was clearly observed. GFAP-positive astrocytic processes guided these neurites. TH-positive neurites arborized overlying S100 beta-positive astrocytes in an area distal to the GFAP-positive astrocytic processes. Treatment with IL-1 beta resulted in an increased area of TH-positive nerve fiber network. In cultures treated with Ara-C, neither astrocytes nor outgrowth of dopaminergic neurites were observed. In conclusion, this study shows that astrocytes play a major role in long-term dopaminergic outgrowth, both in axonal elongation and branching of neurites. The long-term nerve fiber growth is preceded by an early transient outgrowth of dopamine neurites. 相似文献
97.
目的观察肠外营养与生长激素联合应用对大手术术后患者蛋白代谢的影响。方法将拟实施外科大手术(四类以上手术)熏APACHE-Ⅱ评分>7分的患者30例,入院后随机分为3组熏A组穴n=10雪押肠外营养治疗与生长激素穴金磊赛增雪联合治疗组(PN+GH)鸦B组穴n=10雪押肠外营养治疗组(PN)鸦C组穴n=10雪押正常补液组。其中A组在术后第2天开始给予生长激素皮下肌注,连续7d。结果术后8d内,B、C组患者均处于负氮平衡状态,血清白蛋白与胰岛素样生长因子-Ⅰ(IGF-Ⅰ)维持较低水平,A组在术后5d机体开始恢复氮平衡,血清白蛋白与IGF-Ⅰ水平逐渐上升,A组与B、C组比较差异有显著性(P<0.05)。结论较大的外科手术打击后,单纯给予常规的肠外营养要素不能被机体有效的利用,GH能够提高机体对肠外营养要素的利用率,促进机体蛋白合成。 相似文献
98.
神经活素对Pc12细胞作用的初步观察 总被引:1,自引:0,他引:1
从胎脑、颌下腺、肌肉组织中制备神经活素。其性能同脑活素一样:可促进Pc12细胞的突起生长,提高其胞浆内乳酸脱氢酶活性,电泳显示二者有相同的三条带。提示:神经活素有可能替代脑活素应用于临床。 相似文献
99.
ABSTRACT. This study shows that children with late-diagnosed congenital dislocation of the hip (CDH) have close to normal height development during the initial 6.0 years of life. The treatment consisted of immobilization for 0.5 to 1.3 years starting between 0.2 and 0.7 years of age. The present work addresses one specific issue that is related to the age at onset of the childhood component of the ICP growth model. The onset normally appears between 0.5 and 1.0 year of age, and is recognized as an increase in length/height velocity. The onset is thus found during a period of increasing motor activity. The normal successive change from sitting to walking position may have some influence on the onset of this tempo change in early linear growth. The present documentation implies that there is no such influence. In all 14 children with CDH, the onset manifested during the period of immobilization, and the average age at onset was found to be Virtually equivalent with that of the controls. Our conclusion is that immobilization has no significant influence on the age at onset of the childhood phase of growth. The onset is accomplished independent of body position, be it lying down or normal for the age. 相似文献
100.
C. Gupta 《Urological research》1997,25(4):277-281
Previous studies from this laboratory indicated a role for epidermal growth factor (EGF) in androgen-dependent male reproductive tract differentiation of the fetal mouse. Expression of an EGF-like protein during Wolffian duct differentiation was indicated from the determinations by radioimmunoassay (RIA) and radioreceptor assay. To further characterize the protein and to assess its role in male sexual differentiation, expression of the protein has been analyzed by Western blot assay and its tissue-specific cellular expression has been determined by immunocytochemical assay in the present study. Western blot analysis of the 18-day fetal male reproductive tract detected an immunoreactive band of the predicted 6-kDa size. Immunocytochemical analysis also detected EGF-specific immunostaining in the Wolffian duct derivatives. At day 18 of gestation, the staining was localized predominantly in the epithelial nuclei of the Wolffian duct derivatives whereas at days 14 and 16 of gestation, the staining was equally distributed in the mesenchymal and epithelial sites of the Wolffian duct derivative. The intensity of the staining increased with progression of differentiation during the 14th–18th days of gestation. Prenatal exposure to the antiandrogen flutamide significantly reduced the immunostaining of the duct. Thus, a role for EGF in Wolffian duct differentiation is indicated. 相似文献