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排序方式: 共有335条查询结果,搜索用时 17 毫秒
1.
救脑宁注射液对培养神经细胞缺氧缺糖损伤的保护作用 总被引:1,自引:0,他引:1
为了探索“救脑宁”注射液对中风病的疗效机理 ,将原代培养 8~ 12d的新生大鼠皮层神经细胞进行缺氧缺糖处理 ,观察该药对缺氧缺糖损伤神经细胞的影响。结果表明 :缺氧缺糖组细胞上清液中丙二醛 (MDA)含量、乳酸脱氢酶 (LDH)活性较对照组显著升高 ,细胞超氧化物岐化酶 (SOD)活性和细胞生存率则显著降低 ,救脑宁组MDA、LDH显著低于缺氧缺糖组 ,而SOD活性及细胞生存率则高于缺氧缺糖组 (P <0 0 1)。因此 ,抗脂质过氧化损伤、提高神经细胞对缺氧缺糖的耐受性 ,可能是其疗效机理之一。 相似文献
2.
天麻素对缺血再灌注损伤星形胶质细胞的保护作用及其对一氧化氮合成酶活性的影响 总被引:23,自引:0,他引:23
观察天麻素对脑缺血再灌注损伤星形胶质细胞胶原纤维酸性蛋白 (GFAP)表达、乳酸脱氢酶(LDH)漏出量以及一氧化氮合成酶 (NOS)活性的影响。结果 :天麻素大、小剂量组GFAP纤维样改变减轻 ,强阳性反应细胞数减少 ;LDH漏出量下降 ;NOS活性减弱。提示 :天麻素对模拟脑缺血再灌注损伤星形胶质细胞有良好的保护作用 ,其途径之一可能是通过抑制NOS活性的反应性增强来实现的。 相似文献
3.
4.
实热证、虚热证模型大鼠肝细胞琥珀酸脱氢酶活性研究 总被引:7,自引:0,他引:7
观察实热证、虚热证大鼠模型组与治疗组肝细胞线粒体琥珀酸脱氢酶(SDH)活性的变化。用紫外分光光度计测定肝细胞线粒体琥珀酸脱氢酶活性。结果表明:热证时(实热、虚热)SDH活性升高,经清热解毒、滋阴清热中药治疗后,SDH活性有所降低。说明:实热证、虚热证与机体能量代谢呈正相关,中药治疗有利于肝细胞线粒体呼吸亢进的恢复。 相似文献
5.
Nilsen TO Ebbesson LO Kiilerich P Björnsson BT Madsen SS McCormick SD Stefansson SO 《General and comparative endocrinology》2008,155(3):762-772
The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four days and one month seawater (SW) acclimation. Plasma GH and gill GH receptor (GHR) mRNA levels increased continuously during the spring smoltification period in the anadromous, but not in landlocked salmon. There were no differences in plasma IGF-I levels between strains, or any increase during smoltification. Gill IGF-I and IGF-I receptor (IGF-IR) mRNA levels increased in anadromous salmon during smoltification, with no changes observed in landlocked fish. Gill PRLR mRNA levels remained stable in both strains during spring. Plasma cortisol levels in anadromous salmon increased 5-fold in May and June, but not in landlocked salmon. Gill glucocorticoid receptor (GR) mRNA levels were elevated in both strains at the time of peak smoltification in anadromous salmon, while mineralocorticoid receptor (MR) mRNA levels remained stable. Only anadromous salmon showed an increase of gill 11beta-hydroxysteroid dehydrogenase type-2 (11beta-HSD2) mRNA levels in May. GH and gill GHR mRNA levels increased in both strains following four days of SW exposure in mid-May, whereas only the anadromous salmon displayed elevated plasma GH and GHR mRNA after one month in SW. Plasma IGF-I increased after four days in SW in both strains, decreasing in both strains after one month in SW. Gill IGF-I mRNA levels were only increased in landlocked salmon after 4days in SW. Gill IGF-IR mRNA levels in SW did not differ from FW levels in either strain. Gill PRLR mRNA did not change after four days of SW exposure, and decreased in both strains after one month in SW. Plasma cortisol levels did not change following SW exposure in either strain. Gill GR, 11beta-HSD2 and MR mRNA levels increased after four days in SW in both strains, whereas only the anadromous strain maintained elevated gill GR and 11beta-HSD2 mRNA levels after one month in SW. The results indicate that hormones and receptors of the GH and cortisol axes are present at significantly lower levels during spring development and SW acclimation in landlocked relative to anadromous salmon. These findings suggest that attenuation of GH and cortisol axes may, at least partially, result in reduced preparatory upregulation of key gill ion-secretory proteins, possibly a result of reduced selection pressure for marine adaptations in landlocked salmon. 相似文献
6.
7.
Association of the ADH2 genotypes with skin responses after ethanol exposure in Japanese male university students 总被引:2,自引:0,他引:2
BACKGROUND: A contribution of the alcohol dehydrogenase-2 (ADH2) polymorphism to alcohol sensitivity and alcohol drinking behavior is still controversial. In this study, we examined the effects of the ADH2 genotypes on skin reactions to ethanol and habitual alcohol intake among Japanese male university students, controlling for the effects of the low Km aldehyde dehydrogenase (ALDH2) genotype, as an extension of our previous study. METHODS: The study subjects were 357 Japanese male students [average age (mean +/- SD) was 23.7 +/- 3.0 years] in a medical university. The subjects completed a questionnaire regarding self-reported alcohol-associated symptoms and alcohol-drinking behavior. The ADH2 and ALDH2 genotypes were determined through digestion of polymerase chain reaction products by restriction enzymes. All subjects participated in the ethanol patch test. We observed skin responses at 0, 5, 15, and 20 min after removal of the tape. RESULTS: Among the ALDH2*1/*1 genotypes, only some subjects with ADH2*1/*2 or ADH2*2/*2 exhibited a positive response, which increased with increasing time after the removal. However, none of comparisons between the different ADH2 genotypes reached statistical significance. Among the ALDH2*1/*2 genotypes, those with ADH2*1/*2 or ADH2*2/*2 showed a significant increase in response with increasing time after the removal and revealed a significantly higher positivity rate at 15 min than those with ADH2*1/*1. In those with the ALDH2*1/*2 genotype, the positive rate of facial flushing with one glass of beer was higher in those with ADH2*1/*2 and ADH2*2/*2 than those with ADH2*1/*1, although this was not significant. However, the ADH2 genotype did not seem to influence drinking frequency or amounts of alcohol intake in each ALDH2 genotype. CONCLUSIONS: This study finds further evidence for a contribution of the ADH2 polymorphism to skin reactions after either local or systemic ethanol exposure in Asian people. However, the effects of the ADH2 polymorphism may be mild because this polymorphism does not seem to influence alcohol drinking behavior in these study subjects. 相似文献
8.
Daniel GETACHER FELEKE Mehdi NATEGHPOUR Afsaneh MOTEVALLI HAGHI Homa HAJJARAN Leila FARIVAR Mehdi MOHEBALI Reza RAOOFIAN 《Iranian Journal of Parasitology》2015,10(4):505-516
Background:
Parasite lactate dehydrogenase (pLDH) is extensively employed as malaria rapid diagnostic tests (RDTs). Moreover, it is a well-known drug target candidate. However, the genetic diversity of this gene might influence performance of RDT kits and its drug target candidacy. This study aimed to determine polymorphism of pLDH gene from Iranian isolates of P. vivax and P. falciparum.Methods:
Genomic DNA was extracted from whole blood of microscopically confirmed P. vivax and P. falciparum infected patients. pLDH gene of P. falciparum and P. vivax was amplified using conventional PCR from 43 symptomatic malaria patients from Sistan and Baluchistan Province, Southeast Iran from 2012 to 2013.Results:
Sequence analysis of 15 P. vivax LDH showed fourteen had 100% identity with P. vivax Sal-1 and Belem strains. Two nucleotide substitutions were detected with only one resulted in amino acid change. Analysis of P. falciparum LDH sequences showed six of the seven sequences had 100% homology with P. falciparum 3D7 and Mzr-1. Moreover, PfLDH displayed three nucleotide changes that resulted in changing only one amino acid. PvLDH and PfLDH showed 75%–76% nucleotide and 90.4%–90.76% amino acid homology.Conclusion:
pLDH gene from Iranian P. falciparum and P. vivax isolates displayed 98.8–100% homology with 1–3 nucleotide substitutions. This indicated this gene was relatively conserved. Additional studies can be done weather this genetic variation can influence the performance of pLDH based RDTs or not. 相似文献9.
Yoshihiko Maezawa Masayoshi Yamauchi Gotaro Toda Hitoshi Suzuki Susumu Sakurai 《Alcoholism, clinical and experimental research》1995,19(4):951-954
The liver enzymes, alcohol dehydrogenase (ADH) and aldehyde de-hydrogenase (ALDH), which are responsible for the oxidative metabolism of ethanol, are polymorphic in humans. Cytochrome P450IIE1 , an ethanol-inducible isozyme of liver microsomal P450 , is also important in ethanol metabolism. Genetic polymorphisms in the 5'-flanking region of the human cytochrome P450IIE1 gene have recently been reported. We hypothesized that the polymorphisms of ADH , ALDH , and P450IIE1 modify the susceptibility to development of alcoholism. We determined the genotypes of the ADH2 , ALDH2 , and P450IIE1 loci of 96 Japanese alcoholics and 60 healthy male subjects, using leukocyte DNA by the restriction fragment-length polymorphism by polymerase chain reaction. The alcoholics had significantly higher frequencies of the ADH2 1 and ALDH2 1 alleles than did the healthy subjects. No significant difference in the frequency of the P45011E1 genotype was observed between the alcoholics and the healthy subjects. In conclusion, genetic polymorphisms of the ADH and ALDH genes, but not of the P45011E1 gene, influence the risk of developing alcoholism in Japanese. 相似文献
10.
Joan Caballería América Giménez Hernán Andreu Ramón Deulofeu Albert Parés Llorenç Caballería Antonio M. Ballesta Joan Rodés 《Alcoholism, clinical and experimental research》1997,21(9):1619-1622
The effects of zinc on first-pass metabolism (FPM) of ethanol and gastric and hepatic alcohol dehydrogenase (ADH) activities have been investigated in two groups of male Wistar rats fed a liquid ethanol diet with normal zinc content (7.6 mg/liter), or zinc supplemented (76 mg/liter), for 21 days, and in two pair-fed groups receiving the same diets without ethanol. Alcoholic rats with normal dietary zinc had lower FPM (1.64 ± 0.25 vs. 2.43 ± 0.20 mM ± hr, p < 0.05) and gastric ADH activity (184 ± 7 vs. 335 ± 41 μmol/min/mg protein, p < 0.01) than control rats. Zinc supplementation did not produce any change in FPM or in gastric ADH activity in control rats. By contrast, in alcoholic rats, the zinc supplement increased gastric ADH activity (247 ± 31 vs. 184 ± 7 μmol/min/mg protein, p < 0.05) and decreased the areas under the curve of blood ethanol concentrations after the intragastric administration of 0.25 g/kg of body weight of ethanol (0.78 ± 0.07 vs. 1.71 ± 0.24 mM ± hr, p < 0.05), thereby increasing the FPM. In conclusion, in alcohol-fed rats, the administration of zinc supplements restores gastric ADH activity and improves the FPM of ethanol. These effects may be one of the mechanisms in which zinc has a beneficial role in preventing the development of alcoholic hepatic lesions. 相似文献