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21.
In vitro activation of purified rat microsomal glutathione transferase 1 (MGST1) by S-nitrosylation has been recently reported. This study was designated to explore its in vivo relevance. Unexpectedly, we failed to detect S-nitrosylated MGST1 in rat liver microsomes treated with S-nitrosoglutathione (GSNO); neither did we observe MGST1 S-nitrosylation in endotoxin challenged rats. However, by using matrix-assisted laser dissociation/ionization time-of-flight mass spectrometry (MALDI-TOF MS), we identified several other proteins which are susceptible to S-nitrosylation in liver microsomes, including retinol dehydrogenase type I (RODH I), aldolase B, cytochrome P4502C11, and peroxiredoxin 1. Our results suggest that MGST1 S-nitrosylation is unlikely to be involved in the protection mechanism against nitrosative stress caused by endotoxin challenge. Further studies on the novel S-nitrosylable microsomal proteins are also warranted.  相似文献   
22.
Stem cells and periodontal regeneration   总被引:10,自引:0,他引:10  
  相似文献   
23.
In this study, an animal model of multiple system organ failure (MSOF) in rabbits, engendered by feeding E. coli prior to severe hemorrhagic shock, was used for the purpose of investigating 1) the relationship between lipopolysaccharide (LPS) and MSOF, and 2) the effectiveness of Re-LPS antiserum in preventing MSOF. The results showed that endotoxemia occurred very early, and its degree correlated well with that of organ dysfunction. Re-LPS antiserum administration abated the toxic effects and lowered the incidence of MSOF. These results suggest that sequential analysis of circulating LPS levels may be useful for the early diagnosis of MSOF, and that gut-derived endotoxin might play an important role in the pathogenesis of experimental MSOF.  相似文献   
24.
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3'-untranslated region of the CLDN5 locus was associated with schizophrenia (chi(2) = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5'-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (chi(2)) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (chi(2) = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors.  相似文献   
25.
In order to investigate the antagonistic effect of Glycyrrhiza Uralensis Fish (GUF) and Chelidonium maJus L (CML) on gastrccarcinogenesis induced by MNNG in Wastar rats, we treated the rats with MNNG alone (group 1) and with MNNG plus GUF and CML (group 2 and 3) respectively. The incidence of infiltrating adenocarcinoma of the glandular stomach and duodenum in group 2 was significantly lower than that in group 1 (26.7% vs. 67.8%). The differentiation and aggressivenees of carcinomas occured in group 2 were much better and mild than those in group 1. Present study also demonstrated that the inhibitory effect of CML on proliferation of human stomach carcinoma cell line MGC-803 was very remarkable; in addition, GUF and CML were able to antagonise the mutagenic activation of MNNG. These results suggest that GUF and CML may be empoyed in prevention of gastric carcinoma.  相似文献   
26.
用单纯疱疹病毒-1型(HSV-1)感染BGM细胞、Hela细胞、HEL细胞及A549细胞,利用空斑试验,比较四种细胞对HSV-1的敏感性。结果示,HSV-1在BGM细胞培养中空斑形成单位(PFU)数最多,出现细胞病变的时间早。提示BGM细胞可为HSV-1的分离培养提供一种新的、敏感细胞。  相似文献   
27.
对照观察了28例Graves病患者及29名正常人血浆甲状旁腺激素、(PTH)血钙、血磷、碱性磷酸酶的基础值。Graves病组血碱性磷酸酶明显高于对照组,而PTH、钙、磷无显著差异。Graves病组血钙>2.75mmol/L者占21%,与某些文献大致相符。正常组血钙与PTH基础值间呈负相关,而Graves病组该两值间无相关,提示Graves病时血钙浓度的平衡调节中PTH以外的因素如甲状腺激素等可能对其影响较大。  相似文献   
28.
宋柏根  李义清 《肿瘤》1993,13(5):201-204
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。  相似文献   
29.
D Yan  Y Jin  X Zhang  J Li  L Shi  Z Chen  X Li  Y Lin 《中医杂志(英文版)》1997,17(4):294-298
The levels of plasma norepinephrine (NE) and epinephrine (E) were determined by HPLC in 220 patients with various TCM liver syndromes, and in 96 healthy subjects as controls. The plasma NE and E contents were higher in patients with liver excess syndromes, including Ganqi Yujie (GQYJ [symbol: see text]) syndrome, Ganyang Shangkang (GYSK [symbol: see text]) syndrome, Ganhuo Shangyan (GHSY [symbol: see text]) syndrome, and Ganyang Huafeng (GYHF [symbol: see text]) syndrome; while they were lower in patients with liver deficiency syndromes, including Ganqixu (GQX [symbol: see text]) syndrome, Ganxuexu (GXX [symbol: see text]) syndrome, and Ganyinxu (GYX [symbol: see text]) syndrome. Futhermore, when Ganshen Yinxu (GSYX [symbol: see text]) syndrome was turned into GYSK and then into GYHF, the plasma NE and E contents increased in order of precedence; while when GQYJ was turned into Ganyu Pixu (GYPX [symbol: see text]) syndrome, both NE and E contents decreased. The results suggest that the plasma NE and E contents are reliable objective parameters for the study of pathophysiological basis of the liver excess and liver deficiency syndromes, and the liver-kidney and liver-spleen interrelated syndromes.  相似文献   
30.
扩散法被动式甲醛个体监测器(Ⅱ型)的研制   总被引:1,自引:0,他引:1  
介绍了一种基于气体分子扩散原理的被动式甲醛个体采样器,它是在Ⅰ型采样器的基础上完成的。采用甘油(20%)/偏重亚硫酸钠(0.25%)浸渍的定量滤纸(φ42mm)作为吸收层,空气中甲醛扩散到吸收层上,形成稳定的化合物。采样一定时间后,取出吸收层,洗脱后,用AHMT化学比色法测定所采集到的甲醛。这种采样器的平均采样速率为83ml/min,标准偏差为7.2ml/min,与有动力吸收管采样的方法相比较,总不确定度小于±25%。  相似文献   
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