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1.
目的:为了解谷胱甘肽S-转移酶及其同工酶在原发性肝癌患者中的表达情况。方法:采用免疫组化方法对不同分化程度肝癌组织32例和肝硬化组织11例行GSTs和GST-π表达的研究,并以γ-GT作为对照;同时对128例不同肝病患者血清中GSTs活性作检测。结果:GSTs、GST-π及γ-GT的表达与肿瘤的分化程度有关,分化越差,阳性率越低,反之亦然;GST-π在分化良好组阳性表达率明显高于肝为后肝硬化组(P<0.05);血清GSTs活性检测肝癌组与正常对照组相比没有显著性差异(P>0.05)。结论:GST-π是优于γ-GT的肝癌标志酶,尤其在分化程度良好的肝癌,对临床区分肝癌的分化程度有一定的意义。 相似文献
2.
用聚焦层析结合DEAE-Sephadex A-50离子交换层析,从正常人肝浸液中分离得两个精氨酸酶同工酶组分.经聚丙烯酰胺凝胶电泳(PAGE)鉴定从聚焦层析得到的第一峰同工酶组分为一条蛋白带,第二峰具有精氨酸酶活性的蛋白组分的主要蛋白带也极明显。各蛋白质成分向阴极电泳的前后顺序与从聚焦层析洗脱的先后次序一致。两型同工酶的比活力分别约为2050U/mg及790U/mg。用SDS-PAGE检测两型同工酶均由两种亚基组成,且分子量近似。 相似文献
3.
韩猛 《天津医科大学学报》2004,10(3):425-426
目的 :观察病毒性、化脓性脑炎脑脊液(csf)中乳酸脱氢酶 (LDH)活性及其各同功酶活性百分率的变化。方法:病毒性脑炎24例 ,化脓性脑炎15例 ,酶动力学法检测脑脊液总乳酸脱氢酶 (TLDH)活性 ,琼脂糖凝胶电泳法检测脑脊液中LDH各同功酶活性百分率。结果:病毒性脑炎与对照组比较 ,脑脊液总乳酸脱氢酶 (TLDH)明显降低 (P<0.01) ,LDH1同功酶显著降低 (P<0.01) ,LDH5显著升高 (P<0.01) ;化脓性脑炎与对照组比较脑脊液TLDH明显升高 (P<0.01) ,LDH1同功酶明显降低 (P<0.01) ,LDH5明显升高 (P<0.01)。结论:脑脊液TLDH值的测定可以鉴别病毒性、化脓性脑膜炎 ,检测脑脊液LDH各同功酶活性 (LDH1和LDH5)的变化程度对脑炎的进展及预后有一定的价值。 相似文献
4.
Activities of creatine kinase isoenzymes in single skeletal muscle fibres of trained and untrained rats 总被引:1,自引:0,他引:1
Katsumasa Yamashita Toshitada Yoshioka 《Pflügers Archiv : European journal of physiology》1992,421(2-3):270-273
Biochemical changes in the creatine kinase isoenzyme compositions in single muscle fibres of different types in rats were induced by endurance running training. Single muscle fibres were dissected from the soleus and extensor digitorum longus muscles of Wistarstrain male rats trained on a motor-driven treadmill for 16 weeks. Each fibre was typed histochemically (SO, slow-twitch oxidative; FOG, fast-twitch oxidative glycolytic; FG, fast-twitch glycolytic), and the activities of total creatine kinase and its four isoenzymes (CK-MM, -MB,-BB, and mitochondrial creatine kinase) were measured. The endurance training did not affect the total creatine kinase activity, but resulted in significantly increased activities of CK-MB and CK-BB in SO and FOG fibres, and the mitochondrial enzyme activity in FOG and FG fibres. Endurance training induced biochemical changes in the isoenzyme compositions, specifically in FOG fibres. These results suggest that changes in creatine kinase isoenzymes with endurance training reflect changes in the energy metabolism in the different muscle fibres, supporting the hypothesis that the different isoenzymes play different roles in energy transduction. 相似文献
5.
A P Orfanos R Guthrie D C Jinks 《Clinica chimica acta; international journal of clinical chemistry》1987,166(2-3):219-225
Human alkaline phosphatases extracted with butanol from liver, kidney and placenta, and from foetal and adult small intestine each contain fragments with molecular masses within the range of approximately 8 kDa to 20 kDa which can be removed by digestion with bromelain. However, in the case of adult intestine, this fragment (which is presumed to represent a membrane-binding domain) can only be demonstrated in tissue extracted immediately after removal at operation. Similar fragments are also present in foetal intestinal phosphatase in amniotic fluid, and in liver and bone alkaline phosphatases recovered from serum. Again, however, adult intestinal phosphatase from serum differs in the absence of the bromelain-sensitive fragment. These observations indicate differences in the ways in which intestinal and non-intestinal alkaline phosphatases gain access to the circulation, and also have implications for structural studies on intestinal phosphatase extracted post mortem from adult tissue. 相似文献
6.
毒黄素对血清乳酸脱氢酶同工酶的影响 总被引:1,自引:0,他引:1
目的 探讨毒黄素对某些器官的中毒机理。方法 利用从酵米面椰毒假单胞菌中所分离提取出的毒黄素对18例人血清中的乳酸脱氢酶(LDH)及其同工酶进行测定。结果 乳酸脱氢酶总活力下降,LDH1受抑制,活性下降,差异显著。结论 毒黄素可抑制心肌能量供应,毒害心肌。 相似文献
7.
Summary. Superoxide dismutase-like activity (SOD-like), isoenzyme lactate dehydrogenase-C4 (LDH-C4) and NADH-diaphorase activities in spermatozoa have been investigated from 58 normozoospermic and 27 oligozoospermic men. Significantly higher SOD-like, LDH-C4 and diaphorase activities ( P <0.01, P <0.005 and P <0.0001, respectively) were detected in spermatozoa from oligozoospermic men, compared to the activities found in normozoospermic samples. SOD-like activity (mean±SE) in oligozoospermic samples amounted to 8.3±1.6 U 10−8 spermatozoa, while in spermatozoa in normozoospermic men with a sperm concentration above 20 million of spermatozoa per ml amounted to 4.2±0.5 U 10−8 . There was a close correlation between the SOD-like activity and biochemical indicators of the presence of residual cytoplasm i.e. isoenzyme LDH-C4 and NADH-diaphorase (r = 0.53 and r = 0.66 in normozoospermic and r = 0.63 and r = 0.54 in oligozoospermic men, respectively). A positive relationship between SOD-like activity and experimentally-induced lipid peroxidation was detected in 54 infertile men (r = 0.30; P <0.05). These findings suggest that a higher level of superoxide dismutase-like activity may reflect a defect in the development or maturation of spermatozoa and, thereby, a decreased fertility potential. Hence, determination of SOD-like activity may give information on the state of maturity of human spermatozoa, while its role in the antioxidative protection remains to be determined. 相似文献
8.
H. Ohno PhD F. Hirata K. Terayama T. Kawarabayashi R. Doi T. Kondo N. Taniguchi 《European journal of applied physiology》1983,51(2):257-268
Summary Studies of the influences of physical exercise of short duration (bicycle ergometer, 200 W for 30 min) on the activities of carbonic anhydrase isoenzymes (CA-B and CA-C types) and zinc concentration in erythrocytes were made on 5 untrained healthy male volunteers. The subjects were rested for 30 min after the exercise. There were significant decreases in the levels of zinc, CA-B, total carbonic anhydrase activity and CA-B-dependent activity immediately after exercise, but after 30 min of rest they all returned to their pre-exercise levels. No significant change in CA-C level or CA-C-dependent activity was found after exercise. Immediately after exercise, total carbonic anhydrase activity and CA-B-dependent activity following the addition of Zn2+ showed significant increases, compared with their respective activities without Zn2+ addition. However, no such effects were observed just before exercise or after rest; the addition of Zn2+ had no effect on CA-C-dependent activity at any time. A significant correlation was found between the changes in concentration of zinc and CA-B-dependent activity after exercise (r=0.711). The findings of the present study suggest that active CA-B enzymes are converted in part to inactive enzymes during acute physical exercise, possibly by decreased zinc binding. Moreover, the change in CA-B-dependent activity correlated well with the changes in pH and HCO3 concentrations in venous blood (r=0.853 and r=0.718, respectively). One may speculate that an adaptive decrease in CA-B-dependent activity in erythrocytes occurs with increased acidification in blood during heavy physical exercise of short duration.The present study was presented to the Fifth International Symposium on the Biochemistry of Exercise, Boston, June 1–5, 1982 相似文献
9.
目的:探讨碱性磷酸酶(ALP)同工酶在肿瘤诊断中的应用。方法:采用神经氨酸苷酶对正常人及患者血清中ALP同工酶进行处理后进行琼脂糖等电聚焦。结果:121例肿瘤患者中的92例有一等电点为6.2的区带,其阳性率为76%。结论:琼脂糖等电聚焦法分离ALP同工酶在肿瘤诊断中具有一定价值。 相似文献
10.