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41.
将66只昆明小鼠随机分为11组:正常组、模型组及鬼针草全草、叶和枝总黄酮治疗组,每治疗组分为低、中和高剂量(40、80、160 mg/kg)亚组,鬼针草总黄酮(TFB)采用正交试验法提取.治疗组连续灌胃14 d后以四氯化碳(CCl4)建立小鼠急性肝损伤模型,IFCC速率法检测小鼠血清中丙氨酸氨基转移酶(alanine transaminase, ALT)、天冬氨酸氨基转移酶(aspartate transaminase,AST)和乳酸脱氢酶(lactate dehydrogenase,LDH)活性.观察不同生理部位TFB对小鼠急性肝损伤时肝功能的影响,探讨其肝损伤保护作用.结果表明:与模型组相比,叶和全草TFB(40 mg/kg)和枝TFB(80 mg/kg)能极显著降低ALT含量(P<0.01);仅有叶TFB(40 mg/kg)能极显著降低AST含量(P<0.01),而枝TFB(160 mg/kg)能极显著升高AST(P<0.01)含量;叶和全草TFB在40 mg/kg时LDH活性极显著降低(P<0.01).提示鬼针草不同生理部位TFB在急性肝损伤中的作用不同,仅有叶TFB在低剂量(40 mg/kg)时表现出较好的肝保护作用,其余鬼针草各组提示可能肝毒性较大.  相似文献   
42.
Riemerella anatipestifer is the causative agent of septicemia anserum exsudativa in ducks. Its pathogenesis and virulence factors are still unclear. The glycolytic enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), an anchorless and multifunctional protein on the surface of several pathogenic microorganisms, is involved in virulence and adhesion. Whether homologs of GAPDH exist, and display similar characteristics in R. anatipestifer (RaGAPDH) has not been determined. In our research, the RaGAPDH activity from various R. anatipestifer isolates was confirmed. Twenty-two gapdh genes from genomic DNA of R. anatipestifer isolates were cloned and sequenced for phylogenetic analysis. The distribution of RaGAPDH in R. anatipestifer CZ2 strain was confirmed by antisera to recombinant RaGAPDH. The ability of purified RaGAPDH to bind host proteins was analyzed by solid-phase ligand-binding assay. Results revealed that all R. anatipestifer isolates showed different levels of GAPDH activity except four strains, which contained a gapdh-like gene. The gapdh of R. anatipestifer, which is located phylogenetically in the same branch as enterohemorrhagic Escherichia coli (EHEC), belonged to class I GAPDH, and encoded a 36.7-kDa protein. All RaGAPDH-encoding gene sequences from field isolates of R. anatipestifer displayed 100% homology. The RaGAPDH localized on the extracellular membrane of several R. anatipestifer strains. Further, it was released into the culture medium, and exhibited GAPDH enzyme activity. We also confirmed the binding of RaGAPDH to plasminogen and fibrinogen. These results demonstrated that GAPDH was present in R. anatipestifer, although not in all strains, and that RaGAPDH might contribute to the microorganism’s virulence.  相似文献   
43.
通过PCR和DNA测序技术,获得了大鳞副泥鳅(Paramisgurnus dabryanus)线粒体基因组的部分序列,所得4段序列长度共计11552 bp,包括5个蛋白质编码基因(ND1、ND2、ND4、ND4L、ND6和Cytb),14个t RNA基因.本研究获得序列的碱基组成为A 28.9%、C 27.7%、G 15.7%、T 27.7%,可看出(A+T)(C+G);测出的蛋白编码基因的碱基都有一个明显的现象,就是G的含量很明显的少于其他碱基,而C的含量都比较高,并且(A+T)(C+G),这样的结果表现出明显的反G偏倚和碱基组成偏好性.将大鳞副泥鳅Cytb序列与Gen Bank其他6种鱼类的Cytb序列进行%对,表明大鳞副泥鳅与洛东江高丽鳅和俄罗斯泥鳅亲缘关系最近.用NJ法构建7种鱼类的进化关系树,结果表明:大鳞副泥鳅与洛东江高丽鳅和俄罗斯泥鳅最先聚类,再与其他鳅科鱼类相聚,最后与鲤科鱼类斑马鱼相聚,结果与传统分类一致.  相似文献   
44.
Short-chain acyl-CoA dehydrogenase (ACAD) deficiency is an extremely rare inherited mitochondrial disorder of fat metabolism. This belongs to a group of diseases known as fatty acid oxidation disorders. Screening programmes have provided evidence that all the fatty acid oxidation disorders combined are among the most common inborn errors of metabolism. Mitochondrial beta oxidation of fatty acids is an essential energy producing pathway. It is a particularly important pathway during prolonged periods of starvation and during periods of reduced caloric intake due to gastrointestinal illness or increased energy expenditure during febrile illness. The most common presentation is an acute episode of life threatening coma and hypoglycemia induced by a period of fasting due to defective hepatic ketogenesis. Here, the case of a 4 month old female patient who had seizures since the third day of her birth and persistent hypoglycemia is described. She was born to parents of second degree consanguinity after 10 years of infertility treatment. There was history of delayed cry after birth. Metabolic screening for TSH, galactosemia, 17-OHP, G6PD, cystic fibrosis, biotinidase were normal. Tandem mass spectrometric (TMS) screening for blood amino acids, organic acids, fatty acids showed elevated butyryl carnitine (C4) as 3.40 μmol/L (normal <2.00 μmol/L), hexanoyl carnitine (C6) as 0.92 μmol/L (normal <0.72 μmol/L), C4/C3 as 2.93 μmol/L (normal <1.18 μmol/L). The child was started immediately on carnitor syrup (carnitine) 1/2 ml twice daily. Limitation of fasting stress and dietary fat was advised. Baby responded well by gaining weight and seizures were controlled. Until now, less than 25 patients have been reported worldwide. The limited number of patients diagnosed until now is due to the rarity of the disorder resulting in under diagnosis.  相似文献   
45.
The presentation of long-chain fatty acid oxidation disorders (FAOD), unlike short and medium-chain disorders can be with secondary defects in mitochondrial function along with typical features of FAOD. We report an infant with Reye-like presentation and acylcarnitine profile suggestive of very-long-chain acyl-CoA dehydrogenase deficiency who had lactic acidosis and urine gas chromatographic pattern of mitochondrial defects.  相似文献   
46.
将均三嗪型活性染料—活性嫩黄M—7G共价偶于聚乙二醇(PEG6000)分子上,构建双水相系统,能使醇母脱氢酶(以下简称ADH)分配系数增值11倍。观察了影响ADH分配系数的各种因素,设计了借液—液萃取方式快速部分纯化ADN的方案,经部分纯化后,ADH的比活力按每毫克制剂含单位数计算提高至700倍;按每毫克蛋白质含单位数计算提高至16倍,酶活力回收率可达86%。  相似文献   
47.
通过PCR扩增并克隆测序,获得了鳡(Elopichthys bambusa)线粒体ND5基因序列,该基因全长为1836bp,编码611个氨基酸残基的蛋白质,其起始密码子为ATG,终止密码子为TAA.分析该基因碱基组成及密码子使用情况,发现A+T含量高于G+C,并且在密码子第三位点存在明显的反G偏倚.将鳡ND5基因序列与GenBank中其他10个物种的ND5基因序列进行比对,结果表明鳡与鲢鱼的亲缘关系最近,青鱼次之.用NJ法构建11个物种的系统进化树,结果表明雅罗鱼亚科、鲌亚科和鲢亚科之间的亲缘关系很近,而鲤亚科与它们之间的亲缘关系相对较远.  相似文献   
48.
Laboratory infarction diagnostics are based on the detection of elevated serum activities of creatine kinase (CK) Creatine kinase Isoenzyme MB (CKMB) and Transaminases. Determination of these cardiac marker enzymes permits the diagnosis of transmural myocardial infarction. However in such patients the diagnosis of acute myocardial infarction can be confirmed by the clinical symptoms and changes in the ECG, in addition to the enzyme assays. The 50 AMI patients selected in the present study were those admitted to the ICCU of Shri Krishna Hospital, Karamsad. The blood samples were taken at Zero hours (i.e. at the time of admission of the patient). Within 6 hrs of the starting of chest pain, 1.5 million units of streptokinase were mixed with 100 to 150ml of normal saline and administered by infusion over a period of one hour. The blood samples were further collected at intervals of 6 hrs, 14hrs, 32hrs, 48hrs, 5th day and 7th day. The blood samples were analyzed for CK, CKMB, SGOT, α HBDH and Cardiac specific Troponin T. By 6hrs the CK and CKMB values had started rising, the rise continuing at 14hrs with peak values at 32hrs. The CK showed a slight decrease by 48 hrs. The cardiac Troponin T showed wide time window from 4 hrs to 7th day for detecting myocardial damage. The maximum cardiac Troponin T values were during the first 24hrs. Cardiac Troponin T in serum appears to be a more sensitive and early indicator of myocardial cell injury in comparison to CKMB.  相似文献   
49.
Objective  To investigate the protective effect of nicorandil and amlodipine in isoproterenol induced myocardial necrosis in rats. Methods  The effect of nicorandil and amlodipine on bio-chemical parameters during isoproterenol induced myocardial necrosis in rats was examined by determining the activity of creatine phosphokinase (CK), lactate dehydrogenase (LDH), and transaminases (AST, ALT) in the serum of the animals. Results  Isoproterenol (150mg/kg/day) administered rats showed statistically significant rise in activities of LDH(1.02±0.19 to 1.85±0.05), CK(4.3±0.19 to 7.37±.27), AST(0.38±.03 to 0.78±.05) and ALT(0.19±.017 to 0.346±.027) in the serum. Pre-co-treatment of rats with nicorandil and amlodipine significantly lowered the raised levels of these enzymes and thereby restoring the enzyme activity to near normal as was clear from the chart i.e. LDH was 1.10±0.04, CK was 4.37±0.19, AST and ALT were 0.39±0.028 and 0.199±0.04 respectively. Conclusion  It is demonstrated that pre-co-treatment with nicorandil and amlodipine either alone or in combination help in providing protective effect on isoproterenol induced myocardial necrosis.  相似文献   
50.
Glucose-6-phosphate dehydrogenase (G6PD), a cytoplasmic enzyme, plays a protective role during oxidative stress in eucaryotic cells, since they provide coenzymes and substrates to the primary antioxidant enzymes. The redistribution of G6PD in the hippocampus was studied post-ischemia (PI). There was a characteristic localisation of G6PD in pyramidal cell layers of the rat hippocampus. In hippocampus CA1 cells were stained weakly whereas CA3 cells showed strong histochemical staining. Ischemia induced up-regulation of G6PD in the hippocampus was in a specific manner. First, the activity increased in the whole hippocampus (at 4 hours PI) which persisted 6 hrs PI in CA1 area. However G6PD activity decreased in the CA3 area & dentate gyrus. At 10 & 24 hrs PI, activity decreased in CA1 area but normalised in CA3 area & dentate gyrus compared to controls. This suggests that the sensitive CA1 neurons are transiently capable of generating an anti-oxidative arsenal to cope with the oxidative stress in the first few hours PI. We can conclude that the brain contains inducible endogenous mechanisms that are capable of enhancing the ability of neurons to withstand lethal ischemic challenge. (Presently working in Vardhman Mahavir Medical College & Safdarjung Hospital, New Delhi)  相似文献   
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