Antioxidant and glutathione-related enzymatic activities in rat sciatic nerve

The present work tries to establish the antioxidant capacity of the peripheral nervous tissue of the rat, in terms of the enzymatic activities present in this tissue that either prevent the formation of activated species as the semiquinone radical (DT-diaphorase), protect against activated oxygen species (superoxide dismutase, glutathione peroxidase), conjugate natural toxic products or xenobiotics (glutathione S-transferases, especially the activity conjugating 4-hydroxy-nonenal), or complete the glutathione system metabolism (glutathione disulfide reductase, γ-glutamyl transpeptidase). All the activities studied are lower in this tissue than they are in liver, except for γ-glutamyl transpeptidase. The relevance of the results obtained and its possible relationship with different neuropathies is discussed. It is concluded that the peripheral nervous tissue is by far less protected than the liver against oxidative damage.     

刺激视上核对大鼠痛阈及电针镇痛的影响

以钾离子透引起的大鼠甩尾反应为痛指标，观察了电和化学刺激视上核（ＳＯＮ）对大鼠痛阈（ＰＴ）和电针（ＥＡ）镇痛的影响。电刺激ＳＯＮ后，ＰＴ明显高于假刺激组（Ｐ＜０．０５～０．００１），电刺激ＳＯＮ后电针足三里，镇痛效应明显提高，并有明显的量效关系。电刺激ＳＯＮ的近旁部位（０．５—１ｍｍ）对ＰＴ及电针镇痛无明显影响。ＳＯＮ内注射Ｌ－谷氨酸（Ｌ－Ｇｌｕ）后痛阈和电针镇痛效应都明显对照组，也有明显的量效关     

特异性DNA倍增技术检测t-PA cDNA基因在表达细胞中的稳定性

利用特异性DNA倍增技术(polymerase chain Reaction,PCR)检测t-PA cDNA基因在表达细胞基因组中的稳定性,并对所得的PCR反应产物进行了限制性内切酶片段、分子杂交和核苷酸顺序分析等方面的研究,证实了t-PA cDNA基因已插入到表达细胞染色体中。这种方法快速、简便、灵敏度和特异性高,是检测基因工程表达细胞中cDNA基因稳定整合状况的好方法。     

肾细胞癌伴静脉癌栓15例临床分析

１９８５～１９９４年治疗肾细胞癌伴静脉癌栓１５例。按癌栓水平分为肾型１０例，肝下型４例，肝上型１例。Ｂ超和ＣＴ检查总确诊率７３％。手术１４例均完整取出癌栓，术后１３例接受５－ＦＵ加ＭＭＣ方案化疗。随访３个月～５年，１例肝下型和２例肾型无瘤存活分别３６、４３、５２个月，余均在术后２年内死亡。认为Ｂ超与ＣＴ互补应用可基本确诊静脉癌栓，除肝上型和已有血管壁浸润者外大部分癌栓可采用松解游离同时渐渐拉出的方式取出，癌栓水平除肝上型外对预后影响不大。     

Melatonin reduces nitric oxide synthase activity in rat hypothalamus

Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity.     

胃粘膜上皮“适应性细胞保护”机制防止胃肿瘤发生的作用

投用致癌剂的对照组其胃肿瘤发生率为22.2％。若同时给予40％Z醇液空腹灌胃,则胃肿瘤发生率达55.9％。如在给乙醇液前15分钟,先给予4％的辣椒煎液灌胃,则胃肿瘤发生率只有20.0％,相近于对照组的水平(后2组差别有极显著意义,P<0.01)。这种给损伤剂(乙醇)之前先给予微刺激剂(辣椒)所产生的胃粘膜的保护作用,是通过促使胃粘膜上皮细胞合成内源性前列腺素(PGs)来实现的,是一种“适应性细胞保护”机制。这种保护胃粘膜的作用可降低胃肿瘤的发生率。     

A binding site peptide fragment of the nicotinic acetylcholine receptor. Sequence-specific assignment of 1H-NMR resonances in the dodecamer alpha 185-196

The total sequence-specific 1H assignment for the alpha 185-peptide was accomplished by analysis of COSY spectra along with spin-decoupling and confirmatory NOE difference experiments. Some ambiguities in the assignments were successfully addressed utilizing additional peptides with selective amino acid substitutions. The chemical shifts of several of the C alpha H resonances, along with evidence for a slowly exchanging amide at Thr-191 suggest that the alpha 185-peptide may contain a certain amount of non-random coil structure. The role of any such ordered structure in the mechanism of binding to alpha-bungarotoxin remains to be determined. The assignment of the peptide 1H resonances will facilitate the analysis and identification of chemical shift perturbations observed upon formation of the complex between alpha-bungarotoxin and the alpha 185-peptide [7].     

微量元素锌在佝偻病治疗中的效果观察

目的 :探讨补充锌 +维生素D +钙剂治疗佝偻病的效果。方法 :随机分为 3组 ,每组各 5 3例。对照组给予常规治疗 (即维生素D +钙剂 ) ,治疗 1组先给予锌治疗 1个月后 +常规治疗 ,治疗 2组同时给予锌 +常规治疗。 3个月为 1疗程。治疗前后检测血清微量元素及骨碱性磷酸酶 (BALP)等项目。结果 :治疗 1、2组疗效好于对照组 ,差异非常显著 (P <0 0 1) ;治疗1组疗效好于治疗 2组 ,差异有显著性 (P <0 0 5 )。结论 :治疗大多数伴低锌的佝偻病先补锌 1个月 ,再加常规治疗 ,疗效更佳。