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31.
Dionosil Oily (a suspension of propyliodone crystals in peanut oil and powdered tantalum were introduced into the right principal bronchi of rabbit lungs. The left lungs were used as controls. Pressure-volume characteristics of excised lungs with Dionosil Oily or peanut oil demonstrated significantly reduced compliance on inflation at a pressure of 3-4 cm H2O. These lungs also retained less air on deflation and therefore demonstrated a significantly reduced stability index. Histological sections revealed microatelectasis closely associated with crystals and/or peanut oil. Lungs with tantalum powder were not measurably influenced by the bronchographic agents. Surface balance experiments with lung surfactant and synthetic dipalmitoyl phosphatidylcholine (DPPC) demonstrated an increased minimum surface tension due to the oil suspension of propyliodone, peanut oil and particles (propyliodone and tantalum). There is good evidence that the oil suspension of propyliodone reduced the surface activity of lung surfactant in situ. Particles also may prevent the minimum surface tension from reaching relatively low values if they enter the alveoli in sufficient quantities.  相似文献   
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The metabolism of 3H-testosterone by the epididymis and accessory organs of adult male rats exposed continuously to microdoses of cyproterone acetate from subcutaneous capsules were studied. The major metabolite of 3H-testosterone in the epididymis, vas deferens and ventral prostate of control rat was dihydrotestosterone while the formation of androstanediol by these tissues was low. The highest percentage of DHT was formed by the ventral prostate and cauda epididymis. In rats exposed to cyproterone acetate for four months, the conversion of testosterone to DHT was inhibited in all the tissues but maximally in the ventral prostate and cauda epididymis. In these rats, the secretory function of the ventral prostate was normal while that of the epididymis was markedly decreased. These data are discussed based on the differential thresholds of androgens required to regulate the functions of the accessory organs.  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   
37.
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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Clark's equation used in its inverted form (double reciprocal plots) was shown to be valid regarding the interaction of histamine with its receptors in the guinea-pig ileum. Burimamide, a typical H2-receptor antagonist potentiated the stimulating effect of small concentrations of histamine (10(-6) M) on the intestinal smooth muscle, probably, by blocking H2-receptors which may show the opposite effect. The calculated parameters of affinity (pKn) remained constant under different conditions. A linear correlation between length of the preparation and maximal contractions has been found.  相似文献   
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