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991.
992.
G H Mickisch G T Merlino P M Aiken M M Gottesman I Pastan 《The Journal of urology》1991,146(2):447-453
Multidrug resistance in human renal cell carcinoma is mainly caused by expression of the MDR1 gene and is characterized by a broad spectrum cross resistance to many natural product chemotherapeutic agents. This resistance can be overcome by applying chemosensitizers which inhibit the function of the MDR1 gene product P-glycoprotein. The development of new reversing agents with fewer side effects and a higher potency in modifying resistance is a high priority of research on drug resistance. We have evaluated four new verapamil derivatives on 21 primary human renal cell carcinomas in vitro, and also tested them in an MDR-transgenic mice model. These mice express the human MDR1 gene in their bone marrow cells and measurement of their white blood counts provides a simple, rapid and reliable system to screen for the potency of MDR-reversing agents in vivo. We demonstrate here that all four drugs are effective in reversing multidrug resistance in primary cultures of human renal cell carcinomas when used in combination with vinblastine chemotherapy, and to a lesser extent with doxorubicin or daunomycin chemotherapy. Our in vivo data indicate that two of these reversing agents display low toxicity at high concentrations and are more effective at low, clinically achievable concentrations, than the other two drugs and R-verapamil. These results make the two new drugs attractive candidates to be taken into clinical trials. 相似文献
993.
994.
995.
996.
Furfuryl amine salt of 4-chloro-N-(2-furylmethyl)-5-sulfamoyl anthranilic acid was shown to exert more pronounced diuretic and saluretic action in rats, mice and dogs than that of furosemide. The previous administration of furfuryl amine salt of furosemide promoted normalization of the excretory processes of the kidney and increased survival rate of rats in ischemia of the single kidney. The antiedema activity of the drug was found to be much more pronounced than that of furosemide. 相似文献
997.
998.
12-month outcome of patients with major depression and comorbid psychiatric or medical illness (compound depression) 总被引:1,自引:0,他引:1
G I Keitner C E Ryan I W Miller R Kohn N B Epstein 《The American journal of psychiatry》1991,148(3):345-350
OBJECTIVE: Inpatients with major depressive illness often have coexistent nonaffective psychiatric and/or medical conditions. The authors' objective is to address the following questions: 1) What is the effect of comorbid illness on the severity of major depression and associated psychosocial factors? 2) How does the course of depression differ for patients with and without concurrent illness? 3) Do patients with compound depression differ in rate of recovery and time to recovery from patients with pure depression? METHOD: The subjects were 78 patients with a DSM-III diagnosis of major depression who were consecutively admitted to an acute care university-affiliated psychiatric hospital; 37 of these patients had major depression only and 41 had major depression compounded by a coexisting axis I, II, or III condition. The patients were studied while hospitalized and for 12 months after hospital discharge. Instruments used included the Modified Hamilton Rating Scale for Depression, the Global Assessment Scale, and the Social Readjustment Rating Scale. RESULTS: Patients with compound depression reported significantly poorer functioning over the 12-month follow-up period and had lower recovery rates than the patients with pure depression. There were no differences in recovery rates between men and women with compound depression, but significantly more men than women with pure depression recovered. CONCLUSIONS: Compound depression is a common clinical occurrence, the course of illness is more difficult for patients with compound depression than for patients with pure depression, and the recovery rate of patients with compound depression is lower than that of patients with pure depression. 相似文献
999.
Distribution of thymic tissue in the mediastinal adipose tissue. 总被引:5,自引:0,他引:5
I Fukai Y Funato T Mizuno T Hashimoto A Masaoka 《The Journal of thoracic and cardiovascular surgery》1991,101(6):1099-1102
The distribution of thymic tissue in the anterior mediastinal, retrocarinal, and preaortic fat was examined histologically in 27 autopsy subjects. Thymic tissue was found in the anterior mediastinal fat in 12 subjects (44.4%), in the retrocarinal fat in two (7.4%), and in the preaortic fat in none. The finding of ectopic thymic tissue in these areas has not been reported previously, would appear to be surgically inaccessible via a median sternotomy, and may be responsible in part for some of the failures of thymectomy in the treatment of myasthenia gravis. 相似文献
1000.
A survey of endoscopy units in the West Midlands, UK, was undertaken to ascertain the management of colonic perforation during colonoscopy. Fifteen perforations were reported from a total of 17,500 colonoscopies performed in 14 units (a rate of 0.09 per cent). In seven patients the diagnosis was suspected or diagnosed immediately and in the remaining eight 2-72 h later. Four patients with associated pathology (carcinoma, Crohn's disease, ulcerative colitis and a polyp) had resection and primary anastomosis. Seven patients had a simple oversew, four of these having had a delayed diagnosis. In four cases the site of perforation was not identified, but only one patient had conservative treatment. Three patients had drainage and a defunctioning colostomy. There was no significant morbidity following treatment. It is recommended that patients who have had a good bowel preparation should be treated conservatively unless there is a large perforation or an underlying carcinoma. 相似文献