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991.
男科学组织工程研究前景 总被引:4,自引:3,他引:1
利用组织工程技术进行细胞移植的设想 ,已经为男科领域的组织再建工作提供了许多可能。为改善、修复或替代现有组织的功能 ,组织工程的应用研究 ,已经在睾丸间质细胞、睾丸假体、阴茎海绵体、阴茎假体等方面开展。虽然大多数再建工作仍然停留在实验阶段 ,但是有些技术也被用于临床 ,并取得满意的结果。本文简要地综述了组织工程在男科学的应用 相似文献
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995.
目的 观察Wistar大鼠大脑中动脉永久性闭塞后不同时段,缺血半影区小胶质细胞和神经元形态学变化及bFGF在皮层和海马的表达规律。方法 将雄性Wistar大鼠48只,随机分为假手术对照组和永久性局灶性脑缺血组,后者再根据缺血时间不同分5个亚组。假手术组:仅暴露大脑中动脉,2h后断头取脑。永久性局灶性脑缺血组:建立大鼠大脑中动脉闭塞模型,分别于缺血后3d、7d、14d、28d、42d断头取脑,行HE和免疫组化染色。观察梗死灶周围半影区的小胶质细胞和神经元的形态学变化和bFGF在皮层及海马部位的表达规律。结果 HE染色可见脑缺血3d时半影区有少量小胶质细胞出现,14d小胶质细胞增多达高峰,42d趋于稳定。脑缺血3d梗死灶周围皮质神经元和胶质细胞开始表达bFGF,7d表达增强,14d达高峰,28d表达开始减弱,42d仍有一定表达,bFGF在海马的表达也有相同规律。结论 小胶质细胞的肥大和增生性变化以及bFGF的表达,不仅发生于脑缺血早期,晚期仍显示持续性变化,表明小胶质细胞活动以及bFGF的表达贯穿于脑缺血的整个病理过程。 相似文献
996.
前列腺癌细胞株Du145裸鼠胫骨部骨肿瘤转移模型的建立 总被引:2,自引:0,他引:2
目的:建立一种裸鼠前列腺癌骨转移模型,观察肿瘤局部生长和远处转移情况,并进一步探讨其应用价值。方法:9只6周龄雄性BALB/C裸鼠麻醉后,将前肢及左后肢固定,以1 m l TB针筒-29G针头从胫骨头关节窝,刺入骨髓腔缓缓注入人前列腺癌Du145细胞悬液30μl(约5×106个细胞)至骨髓腔,以建立前列腺癌骨转移模型。观察裸鼠生命体征变化。于濒死状态下处死,取右后肢及其附近淋巴结、肺脏和肝脏等标本,用40 m l/L甲醛固定、石蜡包埋、苏木精-伊红染色后显微镜下观察。结果:9只裸鼠中有6只模型建立成功。接种后平均48 d裸鼠出现跛行现象,右后肢胫骨部可触及米粒大小的包块,质硬,进一步发展至小鼠行走障碍。55 d后出现恶病质,解剖后发现右后肢胫骨部骨质疏松,局部有“腐肉”样组织突出髓腔,填塞肌肉间隙,病理证实为肿瘤组织。肝脏泛黄、被膜皱缩,镜下呈急性重型肝炎的病理改变。结论:胫骨内注射细胞悬液制作裸鼠前列腺癌骨转移模型较好地模拟了人前列腺癌在骨骼微环境中的生长及转归情况,是研究前列腺肿瘤骨转移的适宜模型。 相似文献
997.
Alcohol is an important risk factor for human oesophageal cancer. There is evidence from epidemiological studies that some
specific alcoholic drinks, e.g. Calvados apple brandy, are associated with a greater risk than others. Alcohol induces cytochrome
P450 2E1 (CYP2E1) and the hypothesis was tested that different alcoholic beverages, containing a variety of alcoholic compounds,
could differentially induce expression of cytochrome P450 enzymes. Twelve groups of five rats each were treated for 3 days
with different alcoholic beverages (ethanol alone, whisky, farm-produced or commercial Calvados brandy, beer, cider, wine)
adjusted to 4, 10 or 20% of ethanol in drinking water. Immunoblotting using a monoclonal antibody specific for rat CYP2E1
revealed a single protein band in liver microsomes. Densitometric quantitation of microsomal proteins demonstrated a significant
two-, three- and sixfold increase in band intensity after treatment with ethanol concentrations of 4, 10 and 20% respectively,
compared to control rats drinking water alone. There was a dose-dependent increase in liver microsomal metabolism of CYP2E1
substrates (para-nitrophenol and dimethylnitrosamine) in ethanol-treated rats. However, there were no significant differences
in the level of CYP2E1 protein or enzymatic activity between the different alcoholic beverages at the same ethanol concentration.
There was a slight increase in hepatic CYP1A-related enzymatic activities in the alcohol-treated rats compared to the controls,
but no difference between the treated groups either with dose of ethanol or type of beverage. These data show that induction
of CYP2E1 with acute alcohol treatment is predominantly determined by the ethanol content of the beverage.
Received: 10 February 1997 / Accepted: 26 May 1997 相似文献
998.
Fumonisins as a possible contributory risk factor for primary liver cancer: A 3-year study of corn harvested in Haimen, China, by HPLC and ELISA 总被引:13,自引:0,他引:13
Y. Ueno K. Iijima S.-D. Wang Y. Sugiura M. Sekijima T. Tanaka C. Chen S.-Z. Yu 《Food and chemical toxicology》1997,35(12):1143-1150
Employing HPLC fluorometry, gas-liquid chromatography (GLC) and a novel enzymelinked immunosorbent assay (ELISA) based on a monoclonal antibody, 40 corn samples, each collected in 1993 from agricultural stocks for human consumption in Haimen (Jiangsu County) and Penlai (Shandong Province), high- and low-risk areas for primary liver cancer (PLC) in China, respectively, were analysed for fumonisins (FBs), aflatoxins (AFs) and trichothecenes. Levels and positive rates of FBs and deoxynivalenol (DON) were significantly higher in Haimen than in Penlai. ELISA of the 40 corn samples harvested in the two areas in 1994 revealed that FB contamination levels and rates in these areas were comparable to those observed in 1993 in Haimen. ELISA analysis of 1993 and 1994 products revealed a wide occurrence of AFB1 but the positive rates as well as levels were not significantly different between these areas. ELISA of the same sample number of corn harvested in 1995 revealed that FB contamination in Haimen was significantly higher than in Penlai. These 3-yearly surveys of corn samples (240 in total) demonstrated that corn harvested in Haimen was highly contaminated with FBs and that the contamination level, as well as positive rate in 1993 and 1995, were 10–50-fold higher than those in Penlai, suggesting FBs as a risk factor for promotion of PLC in endemic areas, along with the trichothecene DON. Co-contamination with AFs, potent hepatocarcinogens, was assumed to play an important role in the initiation of hepatocarcinogenesis. 相似文献
999.
1000.
levers Carolyn E.; Brown Ronald T.; Lambert Richard G.; Hsu Lewis; Eckman James R. 《Journal of pediatric psychology》1998,23(6):377-388
Objective: To examine moderating effects of family functioningand social support on the relationship of child-related stressorsto caregivers' psychological adaptation in a sample of caregiversof children with a chronic illness. Method: Participants were 67 caregivers of children and adolescentswith sickle cell syndromes. We conducted MANOVAs and subsequenteffect size calculations to determine if family functioningwould buffer the effects of caring for difficult-to-manage childrenwith this illness. Results: Findings supported a moderator effect of family functioningon the association of children's externalizing behavioral problemsto caregivers symptoms of hostility. Greater levels of cohesiveand adaptive family functioning buffered the potential detrimentaleffects of caring for children perceived as hard to manage.No significant associations were obtained between measures ofcaregivers' psychological adaptation and the severity of theirchildren's disease. Conclusions: We make recommendations for family systems interventions,particularly for caregivers of children with behavior problems. 相似文献