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A sublethal concentration of technical grade endosulfan (END) inhibited 35 to 55% of the activities of cytoplasmic malate dehydrogenase (cMDH), mitochondrial malate dehydrogenase (mMDH), and lactate dehydrogenase (LDH) in the liver and the skeletal muscle of a freshwater catfish, Clarias batrachus, after 7 days of exposure. The activity remained in the inhibited state up to 28 days. The withdrawal of END from the medium after 1 week of exposure gradually restored the activities to control levels within 21 days in the skeletal muscle and 28 days in the liver. The administration of actinomycin D or cycloheximide between the 14th and the 21st day of the withdrawal of END almost completely inhibited the withdrawal-dependent recovery in the activities of all the three enzymes. This indicates de novo synthesis of the enzymes during the recovery period. A conjoint treatment of END and triiodothyronine (T3) raised the activities of cMDH, mMDH, and LDH in the liver and the skeletal muscle up to the control levels. This shows that the inhibitory effect of END may be relieved in presence of T3. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed few changes in the pattern of cytoplasmic proteins of the liver and the skeletal muscle in response to exposure to END. 相似文献
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目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
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Ten smoker sportsmen and 17 non-smoker sportsmen and 41 smoker non-sportsmen were studied. Lung function was assessed by means of Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1), the ratio of FEV1 to FVC (FEV1%) and Peak Expiratory Flow Rate (PEFR). For the smokers, all the tests were conducted before smoking (BS) and 30 min after smoking (AS) two cigarettes consecutively to observe the acute effect of smoking. In the smoker sportsmen there was no significant difference between BS and AS measures of lung function. Before smoking smoker sportsmen had lower values for FEV1, FEV1% and PEFR than non-smoker sportsmen (p less than 0.05). However, smoker sportsmen show higher BS values of FEV1 (p less than 0.01), FEV1% (p less than 0.01) and PEFR (p less than 0.05) compared with those of smoker non-sportsmen who had similar smoking indices. These results indicated that the smoker sportsmen, despite exhibiting some degree of lung function impairment in relation to non-smoker sportsmen, still maintained rather better lung function status than the smoker non-sportsmen. 相似文献
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P. Meera P. R. Rao R. Shanker O. Tripathi 《Immunopharmacology and immunotoxicology》1992,14(1):261-282
Mice were fed for 24 weeks with three different subtoxic dosages of γ-HCH (0.012, 0.12 and 1.2 mg/kg) mixed in powdered feed. The immunological profile was assessed at an interval of one month during the entire exposure period. Both the cell mediated and humoral components of immunity showed a biphasic response characterized initially by stimulation followed by suppression in a dose dependent manner. However, γ-HCH did not affect the functional properties of peritoneal macrophages. Histological changes in lymphoid organs were in accordance with the biphasic immunomodulatory effects of γ -HCH. 相似文献
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Rupture of the distal biceps tendon: evaluation with MR imaging 总被引:2,自引:0,他引:2
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S. C. Mishra H. Sharma A. Tripathi 《Indian journal of otolaryngology and head and neck surgery》1993,45(1):29-30
A case of veruccous carcinoma of the maxilla extending to alveulus and palate is reported. Treated with radical maxillectomy: there has been no recurrence within one year. The coexistance of submicous fibrosis and veruccous carcinoma is observed and the histological features of the later are highlighted. 相似文献