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991.
The cardiotoxic effects of hydralazine and prenalterol, given alone and in combination, were assessed in rats and rabbits. Acute myocardial necrosis was induced by a single administration of each drug alone in rats. However, the incidence and severity of lesions were markedly enhanced when both drugs were given in combination. Rats that received the same treatment for 10 consecutive days showed minimal or no acute necrosis, demonstrating the development of a resistance to further cardiotoxic effects of the drugs. Rabbits showed only minimal lesions when either drug was used alone and no enhancement of lesions when they were given in combination. From these data, it is concluded that the possibility of a cardiotoxic interaction exists when these drugs are used in combination and that the heavy rat (500-600 g) is a more sensitive model than the rabbit for studies of this nature. 相似文献
992.
Studies of the blood lipid peroxide status and vitamin E levels in patients with chronic active hepatitis and alcoholic liver disease 总被引:1,自引:0,他引:1
M Mézes A Pár P Németh T Jávor 《International journal of clinical pharmacology research》1986,6(4):333-338
As free radicals and lipid peroxidation are involved in the pathogenesis of different inflammatory diseases of the liver, the blood malondialdehyde content, the activity or quantity of free radical eliminating enzymes and the natural antioxidant, vitamin E serum level has been studied in ten patients with chronic active hepatitis and in six subjects with alcoholic liver disease. Thirty healthy volunteers served as controls. The serum malondialdehyde/thiobarbituric acid reactive substance and its concentrations increased significantly in both hepatitis groups. The superoxide dismutase content was also raised in the patients' sera. The serum glutathione peroxidase (GSH-Px) activity was decreased in both groups, while the red blood cell GSH-Px showed a significantly lower activity in the alcoholic hepatitis patients. Serum catalase activity and vitamin E levels in both types of chronic hepatitis were not significantly different from the healthy controls. 相似文献
993.
994.
995.
T. A. Fedotcheva N. L. Shimanovskii A. I. Senderovich N. S. Chermnykh A. V. Semeikin V. M. Rzheznikov L. E. Golubovskaya G. S. Grinenko V. V. Banin P. V. Sergeev 《Pharmaceutical Chemistry Journal》2007,41(7):345-349
The hormonal compound with the highest cytostatic activity against MCF-7 tumor cells (human breast cancer, BC) and the lowest
activity against normal cells (rat skin fibroblasts) was sought among gestagens, androstenes, and antiestrogencytostatics.
It was found that antiestrogencytostatics and androstenes had the highest cytostatic activity against tumor cells whereas
gestagens and antiestrogencytostatics were least active against fibroblasts. Studies of the activity of the hormonal compounds
in combination with doxorubicin on the viability of MCF-7 and rat skin fibroblasts found that all investigated compounds with
the exception of dehydroepiandrosterone (DHEA) intensify the cytostatic activity of doxorubicin against tumor cells, the greatest
effect seen for antiestrogencytostatics. A chemoprotective effect of androstenes on normal cells was noted.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 7, pp. 3–7, July, 2007. 相似文献
996.
997.
K Tanaka Y Miyake S Sasaki Y Ohya S Miyamoto I Matsunaga T Yoshida Y Hirota H Oda 《Magnesium research》2006,19(4):268-275
There have only been a few studies on the role of mineral intake in tooth loss. We investigated the association between mineral intake and the prevalence of tooth loss in Japan. We used the baseline data on 1002 pregnant women who were enrolled in the Osaka Maternal and Child Health Study between November 2001 and March 2003. Tooth loss was defined as the previous extraction of one or more teeth. Nutrient intake was assessed by a validated diet history questionnaire. Prevalence odds ratios and confidence intervals were estimated by applying a multiple logistic regression model. The adjusted odds ratio upon comparison of the highest quartile with the lowest quartile of magnesium intake was 0.64 (95% confidence interval, 0.42-0.99), showing a tendency for an inverse dose-response relationship (p for linear trend = 0.05). There were no associations between the level of consumption of calcium, phosphate, iron, zinc, or copper and tooth loss. The present findings suggest that intake of magnesium is related to reduced prevalence of tooth loss among young Japanese women. 相似文献
998.
999.
Extranodal lymphomas presenting as soft tissue sarcomas to a sarcoma service over a two-year period.
J K O'Neill V Devaraj D A T Silver P Sarsfield C A Stone 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(6):646-654
Non-Hodgkin's lymphoma usually presents with lymphadenopathy at multiple sites but can also involve any part of the musculoskeletal system. Occasionally the presentation is with a soft tissue mass. The presentation of large, superficial lymphomatous masses is similar both clinically and radiologically to that of soft tissue sarcomas. The six cases of lymphoma presenting to the Exeter Sarcoma Service as suspected soft tissue sarcomas, over a two-year period (2002-2004), are presented. We describe the clinical and imaging characteristics of these tumours and their subsequent management. Our cases showed variability in presentation. Only one of the six cases presented with pain and one with tenderness. Four of the cases had no lymphadenopathy and the other two had lymphadenopathy restricted to one nodal basin. Overlying soft tissue swelling occurred in four cases and in distal limb swelling beyond the mass in one case. Radiologically, lymphomas are known to be likely to exhibit confluent lymphadenopathy that is rare in patients with soft tissue sarcoma. Confluent lymphadenopathy was demonstrated in only one case of this series of patients. It is thought that lymphomas infiltrate across anatomical fascial planes more readily than sarcomas and in four of our six cases this feature was present. Clinical history, examination and MRI are insufficient to differentiate between soft tissue sarcoma and lymphoma and the importance of obtaining a pathological diagnosis prior to surgery is clear. It is crucial to differentiate lymphoma from sarcoma in order to avoid unnecessary excisional procedures in lymphoma patients. 相似文献
1000.