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31.
17 alpha-Alkylated androgens are highly effective in preventing attacks in HAE patients. These drugs, however, seem to be implicated in the development of cholestatic jaundice, peliosis hepatis, and liver tumors. In order to assess the risk-benefit balance of the long-term therapy with androgen derivatives, a follow-up investigation was performed in 13 HAE patients. The results of this study indicate that long-term treatment (15 to 47 mo) with low doses of danazol or stanozolol does not induce significant hepatic damage detectable by laboratory tests or liver biopsy. However, the limited number of patients, although in a rather long period of observation, still suggests a careful control and the use of minimal effective doses.  相似文献   
32.
I.R. Duce  P. Keen 《Neuroscience》1983,8(4):861-866
The uptake of [3H]glutamate and [3H]glutamine into rat dorsal root ganglia has been examined by autoradiography and thin-layer chromatography. [3H]glutamate was selectively accumulated by satellite glial cells and after 10 min, 53% of this had been converted to [3H]glutamine. [3H]glutamine, on the other hand, entered neuronal perikarya and 40% was converted to [3H]glutamate. It is suggested that these selective uptake processes provide supporting evidence for the existence of a neuronal-glial glutamine cycle in dorsal root ganglia. Small dark (B) cells accumulated 6 times as much [3H]glutamine as did large light (A) cells. The reasons for this marked difference in the metabolism of the two main types of dorsal root ganglion neurone are discussed.  相似文献   
33.
The release of [3H]γ-aminobutyrate (GABA) neosynthesized from [3H]glutamine was estimated in one substantia nigra and in the ipsilateral thalamus of halothane-anesthetized cats by perfusing a [3H]glutamine-enriched physiological medium through a push-pull cannula implanted in the two structures under investigation. After two hours of superfusion, muscimol (10?6 M) was delivered through the nigral push-pull cannula for 50–60 min and local- and distal-evoked changes of [3H]GABA release were analyzed. In some experiments, changes of global neuronal activity induced by muscimol application were recorded in different thalamic nuclei, using a bipolar electrode. In a few of the above experiments, biochemical and electrophysiological determinations were simultaneously performed in the substantia nigra and the thalamus. The nigral application of muscimol (10?6 M) induced locally an activation of the substantia nigra reticulata cells, as well as an increase in release of [3H]GABA.Distally, in the thalamus, two types of biochemical and electrophysiological responses were observed according to the localization of the tip of the push-pull cannula or the electrode. (1) An increased release of [3H]GABA and a depression of the global multi-unit cellular activity were obtained in the ventralis medialis-ventralis lateralis, the centralis lateralis and the paracentralis nuclei. These effects could reflect an activation of the GABAergic nigrothalamic neurons projecting to these different thalamic nuclei. (2) In contrast, in the medialis dorsalis paralamellar zone adjacent to the intralaminar nuclei of the thalamus, a decrease of [3H]GABA release and an activation of the multi-unit activity were obtained. These latter results may suggest either a polysynaptic response or the non-GABAergic nature of the nigrothalamic neurons afferent to the medialis dorsalis paralamellar zone.  相似文献   
34.
The cellular localization of the uptake of [3H]taurine and [3H]β-alanine was studied in cultures of rat central nervous system using autoradiography. In brain stem and spinal cord cultures, both amino acids were taken up by neurones and glial cells. In cerebellar cultures, [3H]taurine was accumulated by all glial cells and by a small number of neurones, whereas [3H]β-alanine was only taken up by glial elements. The uptake of both amino acids was sodium and temperature dependent, indicating an active transport mechanism.The results provide further support for the hypothesis that taurine and β-alanine are neurotransmitters in the mammalian central nervous system.  相似文献   
35.
Reflections on experimental and human pathology of aggression   总被引:1,自引:0,他引:1  
On the basis of the already proposed distinction between "normal" and "pathological" aggression in laboratory animals, it is essayed an integration of the experimental findings derived from a specific animal model of aggression with the available clinical information on human violent behavior. The too disregarded importance of the role played by the inhibitory control of brain functions, appears instead reportedly essential in the regulation of emotions and behavior, and is of great relevance in explaining the behavioral changes that follow induced or spontaneous impairment of the serotonergic system of the brain. As a matter of fact, the numerous evidences indicate that genetic predisposition and induced or acquired defects of serotonergic inhibitory control greatly concur to precipitate anomalous strong aggression. Interestingly, the cluster of symptoms presented by laboratory rats in consequence of the serotonergic discontrol, has many unexpected similarities with several pathological conditions of man. This fact confers to laboratory experiments the value of a tool aimed at a better understanding of the biological mechanisms which underlie corresponding alterations of human conduct, with special reference to pathological aggression and violence. In this line, some specific nutrient defects and/or malabsorption conditions can be important in the facilitation or elicitation of mental illness including human aggression. In addition, the efficacy and neurochemical action of those substances capable to partially or completely block or prevent experimental aggression, will likely assume equal relevance in the management or prevention of human violent behavior.  相似文献   
36.
目的 探索Gadd45β和Gadd45γ在亚砷酸钠所致的MIHA细胞周期改变中的作用,为砷中毒的人群防治提供依据。方法 收集贵州省兴仁县雨樟镇交乐病区砷中毒人群以及格沙屯正常人群分别作为砷中毒组和对照组,实时荧光定量PCR检测各组人群Gadd45β和Gadd45γ基因mRNA表达水平。同时,分别以不同剂量亚砷酸钠、不同时间处理MIHA细胞,流式细胞术测定细胞周期改变情况,实时荧光定量PCR和免疫印迹法分别检测Gadd45β和Gadd45γ基因mRNA表达水平和蛋白表达情况。在上述实验基础上,针对Gadd45β和Gadd45γ基因分别设计的siRNA作用于染砷的MIHA细胞,反向验证Gadd45β和Gadd45γ基因在砷致细胞周期改变过程中的影响。统计学分析采用独立样本t检验比较两组间差异,采用单因素方差比较多组间差异。结果 人群实验研究发现,与对照组相比,砷中毒患者Gadd45β和Gadd45γ基因mRNA表达水平升高(t = 2.576,P = 0.011;t = 2.312,P = 0.022);MIHA细胞中,随亚砷酸钠染毒剂量、染毒时间增加,细胞G2/M期比例明显升高(F剂量 = 340.136,P<0.001;F时间 = 49.194,P<0.001);在相对较低亚砷酸钠浓度(低于20 μmol/L)、一定时间内(低于48 h)Gadd45β和Gadd45γ基因mRNA和蛋白表达水平随染砷剂量、染砷时间升高而升高,超过该浓度范围和作用时间后,出现表达下降的现象(Gadd45β:F剂量-蛋白 = 37.568,P<0.001;F剂量- mRNA = 9.771,P<0.001;F时间-蛋白 = 61.144,P<0.001;F时间- mRNA = 46.366,P = 0.001;Gadd45γ:F剂量-蛋白 = 12.989,P = 0.001;F剂量- mRNA = 23.613,P<0.001;F时间-蛋白 = 27.425,P<0.001;F时间- mRNA = 37.969,P<0.001)。转染siRNA分别下调Gadd45β和Gadd45γ的表达后,细胞周期都出现G2/M期比例下调(t = 3.053,P = 0.038;t = 14.47,P<0.001)。结论 砷致Gadd45β和Gadd45γ基因表达水平升高在其诱导MIHA细胞出现G2/M期阻滞过程中发挥重要作用。  相似文献   
37.
 目的 系统评价与分析恩替卡韦(ETV)序贯聚乙二醇化干扰素-α(Peg-IFN-α)与单用ETV在治疗慢性乙型肝炎患者中的临床疗效。方法 计算机检索PubMed、Embase、Cochrane Library、中国知网、万方数据库,搜索有关ETV及ETV序贯Peg-IFN-α治疗慢性乙型肝炎的随机对照试验研究,应用Stata 16.0软件对符合纳入条件的临床研究进行系统评价与分析。结果 共纳入10篇文献,1 250例患者,其中553例患者采用ETV序贯Peg-IFN-α治疗,697例患者单用ETV治疗,两组患者组间基线特征比较,差异均无统计学意义(均P>0.05)。ETV序贯Peg-IFN-α试验组的HBsAg转换率、HBsAg清除率、HBeAg转换率、HBeAg清除率均高于ETV对照组,差异均有统计学意义(均P<0.05)。结论 在慢性乙型肝炎抗病毒治疗中,总体上ETV序贯Peg-IFN-α治疗疗效优于单用ETV。  相似文献   
38.
Receptors for IgM were detected on peripheral blood human eosinophils by a rosette technique with ox red blood cells coated with the IgM fraction of the specific immunserum. Between 14 % and 43 % (mean 27 %) FcµR positive cells were found after an overnight incubation period at 37°C by using this technique. The specificity of the receptors for IgM was assessed by studying the inhibitory capacity of purified human IgM in the rosette assay. From an ultrastructural point of view, the EAM rosette-forming cells are mature eosinophlic granulocytes characterized by a nucleus with a variable number of lobes and a certain number of «first type» granules partially or totally devoid of their content.  相似文献   
39.
40.
观察大剂量丙种球蛋白(IvIg)静脉注射治疗急性期格林-巴利综合征的临床疗效。方法:随机将36例急性进展期格林-巴利病人分成两组,观察组在对照组治疗基础上,应用大量(IvIg)静脉注射。结果:观察组与对照组疗效相比,治愈率及进步率明显高于对照组,显效率接近对照组,肌肉恢复时间观察组中病人病程明显缩短。结论:IvIg治疗格林-巴利使用上越早,疗效越显著。能减少并发症,缩短病程,故此疗法可作为GBS的简便抢救措施。  相似文献   
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