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11.
Intravenous dose-response data obtained from renal clearance studies in anesthetized dogs indicated that bumetanide was approximately 30-fold more potent than furosemide in enhancing sodium excretion. After the administration of 0.01 mg/kg of bumetanide or 1.0 mg/kg of furosemide, the relationship between i.v. diuretic activity and tissue distribution was evaluated. In dog renal clearance experiments, bumetanide and furosemide significantly enhanced urine flow, sodium and potassium excretion. Inulin clearance as an estimate of glomerular filtration rate was not altered by either drug, but sodium reabsorption was decreased with bumetanide (13%) and furosemide (12%). At these diuretic doses, both compounds were bound to dog plasma protein to about the same extent (86-91%), although total plasma levels were 100-fold higher for furosemide. Within 1/2 hour after the i.v. administration of 14C-bumetanide or 14C-furosemide, 86 to 99% of the 14C in urine, plasma, kidney, and liver appeared as unchanged drug. One minute after maximal diuresis bumetanide was found to have a higher affinity (3-fold) for kidney compared to furosemide. These data offer a possible explanation for the i.v. diuretic potency difference between these two compounds. Furthermore, the lack of significant difference in plasma protein binding and the absence of urinary metabolites of either drug suggest that other factors may also contribute to the marked differences in diuretic activity between bumetanide and furosemide.  相似文献   
12.
Over a ten-year period, 129 patients with idiopathic pelviureteric obstruction were randomly selected for splinted or unsplinted pyeloplasties. Of these groups, the patients with splinted pyeloplasties had a lower incidence of postoperative complications. The long-term results were similar in both groups.  相似文献   
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The results of magnet implantation in the upper and lower eyelids of 29 patients suffering from Keratopathia due to lagophthalmos due to facial palsy as well as the surgical techniques involved are described. Contrary to a lateral tarsorrhaphy - still popular today - this method does not alter the form or the size of the palpebral fissure nor does it hinder the visual field. It is technically simple to perform and easily reversible should nerve function recover. The subjective results were also good.  相似文献   
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Official physical examinations of migrant workers upon immigration are required before work permits are issued. The screening of 74,983 applicants during 1972 to 1974 revealed sera reactive to serological tests for syphilis in 0-8 per cent. (range 0-5 to 1-1 per cent.) of all persons concerned and fifteen cases of early syphilis. The incidence of recent infections among immigrants is lower than that reported among the inhabitants of Vienna. General statistics on the spread of venereal diseases among immigrant workers are not available after they start work. Some evidence is provided by those who had to be traced for compulsory examination because they had defaulted from treatment or follow-up, because they were suspected of clandestine prostitution, or because they were reported to be sources of infection. 257 (60-6 per cent.) of 414 individuals who were wanted for reasons of syphilis control could be located and eighteen (7 per cent.) of those who were examined had early infectious lesions.  相似文献   
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Cell proliferation in the prostate complex of the castrate mouse   总被引:1,自引:0,他引:1  
Cell proliferation during 100 h of continuous androgen challenge was studied in the seminal vesicle and coagulating gland of Balb/c mice castrated 3 days or 14 days prior to the first daily injection of 250 mug testosterone propionate. Continuous labelling with [3H] thymidine indicated that the seminal vesicle was almost totally responsive to androgen, as early as 3 days after castration, whereas the androgen sensitivity of the coagulating gland increased from 30% at 3 days after castration to 85% at 14 days after castration. In both tissues the magnitude of the proliferative reaction could be related to the extent of cell loss prior to stimulation. The duration of the pre-replicative phase in the response of the seminal vesicle to androgen was 20-25 h both at 3 and 14 days after castration. In the coagulating gland the pre-replicative phase was 40 h at 3 days after castration and 20 h at 14 days after castration. The maximum uptake of [7alpha-3H] testosterone administered to mice 3 days after castration was significantly greater (P less than 0-01) in the seminal vesicle compared to the coagulating gland. At 14 days the seminal vesicle and coagulating gland exhibited a similar capacity for uptake. The in vivo metabolism of [7alpha-3H] testosterone was studied by thin layer chromatography 30 min and 120 min after administration. A high proportion of the radioactivity extracted from all the tissues was associated with highly polar steroids. At 3 days after castration, the seminal vesicle, 2 h after administration of radioactive testosterone, retained a much higher proportion of radioactivity associated with dihydrotestosterone than did the coagulating gland. The localization of steroid in mice 3 days after castration was studied by dry-mount autoradiography at intervals up to 2 h after the injection of [1,2,6,7(n)-3H]-testosterone. A heavier deposition of silver grains was observed over autoradiographs of the seminal vesicle. In the seminal vesicle the grains were primarily located over nuclear areas whereas in the coagulating gland the grains were diffusely distributed over both nuclear areas and over cytoplasmic areas.  相似文献   
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In 51 actively purging cholera patients the efficacy of doxycycline, a long-acting tetracycline, was compared with a placebo and tetracycline hydrochloride. Seventeen patients who were given doxycycline at the recommended dose of 2 mg/kg at the beginning of the study, at 12 h, and at the repeated dose once daily purged a mean volume of 5.1 liters of stool and received an average of 5.7 liters of intravenous fluid. Nineteen patients receiving the placebo purged 10.1 liters of stool and received 9.7 liters of fluid. Fifteen patients given tetracycline hydrochloride at 6-h intervals passed 4.8 liters of stool and received 5.5 liters of fluid. The durations of diarrhea calculated in 8-h periods were 3.5, 8.0, and 4.1 h in the respective groups receiving doxycycline, placebo, and tetracycline. The differences between the doxycycline and placebo treatments and the tetracycline and placebo treatments were statistically significant. Those receiving doxycycline became vibrio-free in about 3 days as compared with 2 days for those receiving tetracycline; the group given the placebo were vibrio positive for the duration of their hospitalization. The results show that in the treatment of cholera the administration of doxycycline once daily has effects equal to those when tetracycline is administered at 6-h intervals. This is a distinct advantage because it decreases the demand on nursing personnel in epidemics. Also, doxycycline may be safely administered in cases of suspected renal failure from prolonged shock in cholera.  相似文献   
20.
1. The effects of intravenous (i.v.) administration of the vasodilator drugs prazosin or diazoxide on blood pressure and plasma renin activity were evaluated in the anaesthetized dog. 2. Prazosin and diazoxide both induced a rapid reduction in the mean arterial pressure to 73% and 75% of control values respectively. 3. Prazosin lowered plasma renin activity to 62% (P less than 0-025) of the control value whereas diazoxide raised plasma renin activity to 178% (P less than 0.05) of the control value. 4. The combination of vasodilatation and low renin activity observed following the administration of prazosin is unique, and may have clinical significance if these factors reduce the vascular complications of hypertension.  相似文献   
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