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81.
Continuous proteolysis resulting in consumption of major cytoskeletal proteins may be essential for platelet activation and aggregation. In this study we evaluated the effect of a known protease inhibitor, Leupeptin, on agonist induced platelet aggregation and secretion. Platelets exposed to 10 ugs/ml of Leupeptin did not aggregate in response to the action of thrombin (0.2u/ml). However, a concentration of Leupeptin as high as 250 ugs/ml did not prevent arachidonate induced aggregation and secretion. Leupeptin (100 ugs/ml) effectively blocked thrombin (0.2 u/ml) induced elevation of cytosolic calcium, but did not affect arachidonate induced elevation of platelet intracellular calcium levels. At a concentration of 100 ug/ml, Leupeptin effectively blocked thrombin (0.5u/ml) induced clot formation of platelet poor plasma, suggesting that it can exert its effect on thrombin by preventing fibrinogen degradation. Effective Ki for the competitive inhibition of thrombin induced hydrolysis of a chromogenic substrate, S2238, by Leupeptin was 2.4 uM. Leupeptin inhibition of platelet function was reversible by washing platelets free of the polypeptide. Results of our study demonstrate that Leupeptin inhibits thrombin induced platelet activation, probably by interfering with its proteolytic activity on the platelet surface membrane. However, inhibition of platelet surface membrane associated proteases did not prevent activation of platelets by other agonists. 相似文献
82.
Radhaiah V. Girija M. Jayantha Rao K. 《Bulletin of environmental contamination and toxicology》1987,39(6):1006-1011
Bulletin of Environmental Contamination and Toxicology - 相似文献
83.
Jaggi Rao Theodore A Golden Richard E Fitzpatrick 《Dermatologic surgery》2002,28(8):768-71; discussion 771
BACKGROUND: With the popularity of laser skin resurfacing for the correction of photoaging and the improvement of acne scarring, it is important to note complications that may result from this procedure. Infections must be recognized and treated early, as some can result in permanent local destruction and systemic spread to other body sites. OBJECTIVE: To increase the awareness of an unusual infection that may result from laser resurfacing. METHODS: We report the case of a 52-year-old woman who presented with two symmetrical nodules 1 month after full-face skin resurfacing with CO2 laser. These were found to be abscesses caused by Mycobacterium fortuitum infection. RESULTS: The diagnosis was established following surgical debridement and subsequent culture grown from the exudate. Oral antibiotic treatment guided by organism sensitivity resulted in complete clearance of the infection with no recurrence or sequelae after 3 years of follow-up. CONCLUSION: This case demonstrates that atypical mycobacterial infections may arise after laser resurfacing procedures, despite proper technique, sterile instrumentation, and appropriate perioperative medications and postoperative wound care. If diagnosed and treated early, this potentially disastrous complication can be cured with no permanent sequelae. 相似文献
84.
Methylcholanthrene (approximately 300 micrograms) plus beeswax-impregnated thread, when placed inside the canal of the uterine cervix of virgin female adult mice for 30, 60 and 90 days produced cervical tumors in 0.0, 10 and 30% of mice, respectively. Employing this experimental cervical carcinogenesis model system, the present study evaluated the modulatory influence of medroxyprogesterone acetate (MPA) on the incidences of precancerous and cancerous lesions in the cervical epithelium as well as on phase I and phase II drug metabolizing enzymes and acid soluble sulfhydryl level in the liver. Intramuscular administration of MPA (50 micrograms every 5th day) to the carcinogen-thread inserted mice for 30, 60 and 90 days produced cervical tumors respectively in 0.0, 13.3 and 60.5% (P less than 0.05) of mice. A significant increase (P less than 0.05) in hyperplasia was also observed in the present study. A significant decrease in cytochrome b5 was found after 30 days. 相似文献
85.
A study was undertaken to assess the health, nutrition and psychosocial profile of Institutionalized children in four States--Uttar Pradesh, Andhra Pradesh, Karnataka and West Bengal. A sample of 3,822 children from 70 institutions in 6-18 years age group formed the subjects of the study. It was observed that the destitute children were mainly taken care of in three types of institutions, viz, Voluntary, Government Aided and Government run institutions. Calorie deficiency and deficiency of Vitamins and minerals characterized the diets of these children. In general, there was no deficit of protein in their diets. Growth wise, these children were retarded both in height and weight compared to standards. However, they fared better in comparison to their age and sex counterparts in the rural and urban poor. Psychosocial profile of these children indicated that the prevailing environment in the institutions is less conducive for intellectual stimulation but not so for the development of skills of self-help, locomotion, socialization and imagery. 相似文献
86.
87.
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
88.
89.
L’incontinence fécale est un problème fréquent en pratique médicale mais souvent sous-estimé et mal traité. Cet artiele revoit l’épidémiologie, les mécanismes pathophysiologiques et les approaches diagnostiques des patients souffrant d’incontinence fécale. De plus, je ferai une synthèse des traitements médicaux de l’incontinence fécale. Une anamnèse systématique et une étude de la morphologie et de la physiologie anorectales permet souvent de mettre en évidence les mécanismes pathogéniques sous-jacents et d’orienter le traitement. 相似文献
90.
Summary. Parameters were obtained from the reproductive organs of ethanol-fed, gossypol-treated Sprague Dawley rats. The experimental animals were fed either on a normal (15.17%) or low protein (8.00%) diet. Measurements included reproductive organ weights, seminal characteristics, serum concentration of testosterone and histological, stereological and histomorphometric evaluation of the testis. The testis size, length and diameter of the seminiferous tubule had the least values in the protein-malnourished, gossy-pol-treated rats (3.01±0.26 g, 0.56 ± 0.03 m, 281.34±11.30 μn), in comparison to corresponding animals which had received ethanol simultaneously with gossypol (3.40 ± 0.25, 0.71±0.06m, 314.42 ± 11.61 μn). As gossypol and ethanol are both associated with reduced reproductive capacity, this unexpected but interesting finding lends support to the hypothesis that either a normal dietary protein or ethanol consumption may modify the action of gossypol on body tissues, including the testis. This effect, presumably mediated through changes caused to the bioavailability of gossypol, modifies its antifertility activity. The present observation further highlights the need to consider the concurrent administration of other drugs, such as alcohol, and the nutritional status in the evaluation of gossypol for various potential uses. 相似文献