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The influence of food and water intake on mefenamic acid (N-2,3-xylylanthranilic acid) bioavailability from commercial capsules of high bioavailability was studied in four healthy male volunteers. The drug was administered as a single oral dose of 250 mg, under fasting or nonfasting conditions, and a 4 X 4 Latin-square design was used. Eight blood samples were collected over a 24-h period following drug administration, and the drug plasma concentrations were determined by HPLC. The bioavailability of mefenamic acid from capsules was markedly influenced in the fasting subjects by the water but not by the food intake. A good correlation was found between the bioavailability and amount of water ingested with the drug in the fasting subjects. The area under the plasma concentration-time curve (AUC0-infinity) of mefenamic acid was highest when the capsule was taken with 50 mL of water or immediately after a meal. Increasing the amount of water from 50 to 500 mL in the fasting subjects caused a significant reduction in AUC0-infinity.  相似文献   
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Norfloxacin, a new quinolinecarboxylic acid derivative, was administered to 30 male patients with gonococcal urethritis at a daily dose of 600 mg for 7-21 days. The clinical response was evaluated after administration of 7 days as excellent; Negative culture of N. gonorrhoeae. WBC less than 3/hpf in first voided urine sediment, good; Negative culture, WBC greater than or equal to 3/hpf, and poor; Positive culture. The result was excellent in 14 cases and good in 16 cases. No subjective side effects were observed. The minimum inhibitory concentration (MIC) distribution against the clinically isolated 30 strains of N. gonorrhoeae ranged from 0.0096 micrograms/ml to 0.34 micrograms/ml. Seven of thirty strains were resistant to ABPC. The MIC of these 7 strains ranged from 0.018 micrograms/ml to 0.18 micrograms/ml. Seven cases with ABPC resistant strains had a similar clinical response to other cases. Twelve patients (40%) developed post gonococcal urethritis for 7-14 days after treatment. Clinical observation of this series suggests that a 7 day therapy of Norfloxacin for the patients with gonococcal urethritis is sufficiently effective and that treatment should be changed to other antibacterial agents in the case of post gonococcal urethritis, since continuous administration for more than 7 days of Norfloxacin is not so effective.  相似文献   
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OBJECTIVES: Lateral biopsies are thought to have a better cancer detection rate compared with standard sextant biopsies. This study aimed to determine whether lateral peripheral zone biopsies in Japanese men who underwent transrectal ultrasound-guided prostate biopsies provided a significantly higher cancer detection rate than sextant biopsies. METHODS: Between 1999 and 2004, data were collected from 461 men who underwent prostate biopsy and had enough data regarding the performance of lateral biopsies for statistical analysis. There were two categories in this study: (i) patients who underwent sextant prostate biopsies; and (ii) patients who underwent sextant biopsies plus lateral biopsies. RESULTS: Prostate cancer was detected in 141 (30.6%) of 461 patients. It was detected in 24 (22.2%) of 108 patients who underwent sextant biopsies and 117 (33.1%) of 353 patients who underwent sextant plus lateral biopsies. Lateral biopsies were not associated with a statistically higher rate of positive biopsy findings; however, we found a significantly higher ratio of patients with positive findings in those with prostate specific antigen (PSA) levels 10 ng/mL (one of 71, 1.4%) among those who had positive cores only in lateral biopsy samples (P < 0.0001). CONCLUSIONS: Lateral biopsies did not show a significantly higher detection ratio of prostate cancer compared to sextant biopsies. However, lateral biopsies were more effective than sextant biopsies in patients with lower PSA levels. Our findings might be useful for the establishment of biopsy strategies to detect prostate cancer, especially in patients with lower PSA levels.  相似文献   
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Repeated administration of a large dose of methamphetamine (MA) (25 mg/kg, i.p. twice daily for 4 days) to mice enhanced locomotor activity and decreased stereotyped behavior following a subsequent injection of MA. Simultaneous determinations of catecholamines revealed a depletion of brain dopamine. The moderate doses of haloperidol significantly enhanced MA-induced locomotor activity in mice. A significant enhancement of MA-induced locomotor activity was observed in the rats pretreated with 6-hydroxydopamine into the striatum, and this effect correlated negatively with the striatal dopamine level. These results suggest that hypofunction of striatal dopaminergic neuron systems induced by repeated administration of MA may be one of possible mechanisms of the enhancement of MA-induced locomotor activity due to the decrease of stereotyped behavior.  相似文献   
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When the neural tube of avian embryos is separated from the notochord and floor plate, motoneurons in the spinal cord fail to develop. In order to investigate the factors involved in this phenomenon, cell proliferation activity and cell death were observed following paramedian incision of the neural tube at the level of the segmental plate using colchicine, BrdU, and TUNEL methods. If the notochord and/or floor plate produces a substance(s) that promotes cell division in the basal plate neuroepithelium or that supports the survival of the motoneuron's neuroblasts, mitotic figures should not be present in the neuroepithelium nor should substantial cell death be observed in the ventral aspect of the notochord- and floor plate-deprived neural tube. Surprisingly, however, neither result was observed in the present experiments, with the exception of a considerable amount of homogeneously distributed cell death. Neuroepithelial cells continued to proliferate and gave rise to neuroblasts. Nevertheless, motoneurons failed to develop, and the neural tube was enveloped by only the basement membrane of the alar plate (S. Hirano and H. Tanaka, 1994,Dev. Growth Differ.36, 481–488). These morphological results revealed that the cause of the development of the anterior horn lacking a neural tube in the notochord- and neural tube-eliminated embryos is not the elimination of the source of the surviving factor(s) of the motoneuron's neuroblasts, but rather the elimination of the signals to induce the motoneurons, derived from the notochord and/or floor plate. The larger amount of cell death in the neural tube on the experimental side suggests that a nonspecific survival factor(s), necessary for the survival of a variety of types of neuroblasts, is also produced by the notochord and/or floor plate.  相似文献   
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Transrectal ultrasonotomography is useful in following patients with benign prostatic hypertrophy, because prostatic shape and weight are precisely assumed. We studied the effect of chlormadinone acetate (CMA) on benign prostatic hypertrophy. CMA (50 mg/day) was administered to 30 patients with benign prostatic hypertrophy. Weight reduction over 10% of the gland was noticed in 24 cases (80%). Mictional conditions were improved in 70% subjectively and in 71.4% objectively. However, the number of nocturia decreased in only 18.9%. Reduction rate of the weight was unrelated with the weight of prostate before administration of CMA. Duration of administration of CMA and the reduction rate were estimated. There was no definite difference in reduction rate for the first 15 months, but there was a slightly high reduction rate after administration of CMA for more than 24 months. In 3 cases, the shape and weight of prostate were studied after discontinuation of CMA. The size of prostate showed a tendency to increase gradually.  相似文献   
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