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991.
Melphalan and analogous aniline mustard derivatives were tested on antitumor activity in vitro. All compounds showed similar antiproliferative effects against melanoma B16, sarcoma 180 and leukemia P388D1. Thus, the singular clinical efficiency of melphalan may not simply be explained by a selective uptake employing amino acid carrier systems of tumor cells.  相似文献   
992.
We selected a group of male dialysis patients complaining of sexual dysfunction in whom penile vascular insufficiency and drug-induced impotence had been excluded. Monitoring of nocturnal penile tumescence was used to confirm organic disturbance. Patients with normal serum prolactin concentrations (n = 18) had significantly lower serum zinc values than normal controls (P less than 0.001) and were entered in a 6-month double-blind study comparing oral zinc acetate with placebo. Patients with elevated prolactin concentrations (n = 8) were entered in a 3-month double-blind crossover study comparing oral pergolide mesylate with placebo. In the zinc study, serum zinc concentrations increased (P less than 0.05) in the zinc-treated but not the placebo-treated group. One of nine patients receiving zinc reported improved sexual function, as did two of nine patients receiving placebo. There were no significant changes in sperm counts, nocturnal penile tumescence, testosterone, sex hormone binding globulin or gonadotrophin concentrations in either treatment group. In the pergolide study, serum prolactin values decreased (P less than 0.01) in the pergolide but not in the placebo treatment period. One patient reported improved sexual function during the pergolide treatment period and two during the placebo period. There were no significant changes in sperm counts, nocturnal penile tumescence, testosterone, sex hormone binding globulin or gonadotrophin concentrations after pergolide. These studies show no benefit of zinc or pergolide compared with placebo in the treatment of uraemic impotence.  相似文献   
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A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14-15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized.  相似文献   
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Syphilis can be spread during the practice of dentistry by direct contact with mucosal lesions of primary and secondary syphilis or blood and saliva from infected patients. The dentist also can play an important role in the control of syphilis by identification of the signs and symptoms of syphilis, patient education, and referral. The incidence of syphilis and the impact of control measures are presented with the emphasis on the past 5 years. The signs and symptoms of primary, secondary, latent, and late (tertiary) syphilis are reviewed. Current medical treatment is presented. The oral manifestations of syphilis are discussed as well as the dental management of the infected patient.  相似文献   
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