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991.
The pharmacokinetics of dibenzylamine administered in a sustained drug delivery system with cefazolin was studied after i.m. administration of a dose of 1250 mg to healthy volunteers. The serum and urine levels of dibenzylamine were determined by a GLC technique using a specific nitrogen-phosphorus detector. Characterization of the kinetic parameters was performed by applying compartmental and non-compartmental analysis. Dibenzylamine was found to reach concentrations close to 300 ng ml-1 approximately 5 h after administration. The elimination constant had a value of 0.832 +/- 0.821 h-1 (mean +/- S.D.), which is higher than the release constant of the derivative (0.109 +/- 0.072 h-1) (mean +/- S.D.). These results show that release of dibenzylamine may be considered the limiting kinetic process, which governs the elimination of the product from the organism. Only a small amount of dibenzylamine is excreted in urine unchanged 3.43 +/- 3.28 per cent (mean +/- S.D.). Using the pharmacokinetic parameters calculated for dibenzylamine, a prediction has been made of the concentrations reached in a multiple dosage regimen after administration of a dose of 1250 mg every 24 h. The accumulation factor was 1.09. 相似文献
992.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14
993.
Experience in the management of myelomeningocele in Puerto Rico 总被引:1,自引:0,他引:1
The medical records of 128 children with myelomeningocele who were treated at the Pediatric University Hospital, Puerto Rico Medical Center, from January, 1980, to July, 1985, were reviewed retrospectively. The medical and surgical management during the first hospitalization of these children was studied in detail for predefined parameters. The average age at the time of myelomeningocele repair was 6.6 days. Statistical analysis showed that repair of the myelomeningocele defect before 48 hours of age did not reduce the occurrence of ventriculitis. The incidence of ventriculitis secondary to the management of the myelomeningocele lesion was 12.5%. Complications after repair of the myelomeningocele (including skin flap necrosis, cerebrospinal fluid leaks, and wound infection) were present in 43.8% of the patients who developed ventriculitis and in 19.0% of those who did not. This observation is statistically significant (p = 0.03) and indicates that complications of healing after myelomeningocele repair represent the most significant risk factor for the development of ventriculitis. 相似文献
994.
R Martínez Jordá C Aguirre R Calvo J M Rodríguez-Sasiaín S Erill 《The Journal of pharmacy and pharmacology》1990,42(3):164-166
Penbutolol is a beta-adrenoceptor antagonist that is extensively bound to alpha 1-acid glycoprotein (alpha 1-AGP), a protein that increases in inflammatory diseases thereby binding more drug in such conditions. Changes in serum binding can lead to modifications in the pharmacokinetics and pharmacodynamics of a drug, therefore, the central effect (as the anticonvulsant response) and brain uptake of penbutolol given intravenously to mice with experimental inflammation have been measured. A significant decrease of the central effect of penbutolol and its brain uptake was seen in diseased when compared with control animals (P less than 0.01). A parallel decrease in free fraction of penbutolol in diseased vs normal animals was detected. These results suggest that there is an increase in serum binding of basic drugs related to increments in alpha 1-AGP concentration, which reduces their central pharmacological effect. 相似文献
995.
A total of 163 Hysterothylacium aduncum specimens, obtained from two gadoids and one percid, were studied by electrophoresis of the enzymes glucose phosphate isomerase
and phosphoglucomutase. The two loci deviated significantly from the Hardy-Weinberg equilibrium, both when considering all
specimens and when distinguishing the hosts. This could suggest that there is no single species in either case.
Received: 16 June 1997 / Accepted: 11 July 1997 相似文献
996.
Distribution of Hepatitis B Virus Genotypes in Two Different Pediatric Populations from Argentina 总被引:12,自引:2,他引:10 下载免费PDF全文
V. A. Mbayed J. L. Lpez P. F. S. Telenta G. Palacios I. Badía A. Ferro C. Galoppo R. Campos 《Journal of clinical microbiology》1998,36(11):3362-3365
Differences in pathogenesis and the probability of becoming a chronic carrier depend on the age at which hepatitis B virus (HBV) infection is acquired, ranging from 82% in infants less than 6 months of age to 15 to 30% in older children. HBV genotypes from 22 pediatric patients from two areas that differ in prevalence have been determined. Phylogenetic analysis shows a clear difference between the genotype distribution in Buenos Aires, a low-prevalence area, and that found in Gualeguay, Entre Ríos, a high-prevalence area. While the analysis allocated the sequences in the Buenos Aires group to genotypes A (36%), D (9%), and F (55%), the Gualeguay group presented exclusively genotype A isolates with very low nucleotide divergence, which suggests a strong founder viral population. The high prevalence of genotype F in the Buenos Aires group and its high intragroup heterogeneity agree with the American origin of this genotype. 相似文献
997.
Anderson RA; Evans LW; Irvine DS; McIntyre MA; Groome NP; Riley SC 《Human reproduction (Oxford, England)》1998,13(12):3319-3325
Follistatin is a binding protein for the activin and inhibin family of
hormones, regulating their biological activity. In the male reproductive
tract, the interaction of these factors is likely to be involved in the
regulation of the proliferation of several cell types. We have investigated
the presence of follistatin and activin A in seminal plasma using specific
immunoassays and have localized follistatin and activin/inhibin subunits in
the adult human testis, prostate and seminal vesicle to establish their
likely sources. High concentrations of immunoreactive follistatin were
present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in
peripheral plasma) and were similar in men with oligo/azoospermia and
following vasectomy. Follistatin immunoreactivity was localized to both
Leydig and Sertoli cells of the testis, and to epithelial cells of the
prostate gland and seminal vesicle, which are likely to be the predominant
sources of the hormone in seminal plasma. Activin A was also present in
seminal plasma in normal men but was undetectable following vasectomy, thus
deriving from the testis. Consistent with this finding, the betaA-subunit
was immunolocalized in Sertoli and Leydig cells but was not present in
seminal vesicle or prostate gland. The functional significance of the high
concentrations of follistatin secreted into seminal plasma by the prostate
gland and/or seminal vesicle is uncertain, but they may regulate the
biological activity of testis-derived activin A and inhibin B.
相似文献
998.
北京市城区四~六年级小学生体力活动现状 总被引:4,自引:3,他引:1
目的 了解小学生体力活动模式,为采取有效的措施促进他们积极参加体力活动、制定相关政策和健康目标提供依据。方法 随机选取北京市城区4所小学四~六年小学生453名,采用问卷调查和Caltrac体力活动测量仪收集其上周参加体力活动的情况。结果 男女生经常参加的业余活动依次为上下楼梯、劳动、步行、跑步等,男女生平均每天参加业余体力活动的时间分别为1.30、1.1lh,每天业余体力活动消耗的能量分别为27.89、23.65kJ/kg,每天总体力活动消耗的能量分别为42.17、35.53kJ/kg,每天静坐时间分别为2.00、1.79h,男女生各评价指标之间差异均无显性。结论 男女生经常参加的活动类型大致相同,活动水平接近。 相似文献
999.
E Díaz-Rubio J Jimeno A Antón E Aranda J Sánchez B Massuti J Cruz-Hernández A Carrato M Martin J Belón 《American journal of clinical oncology》1992,15(1):56-60
One hundred sixty consecutive patients with histologically confirmed colorectal cancer (advanced disease) without prior chemotherapy were entered in a randomized trial comparing 5-fluorouracil (5-FU) 1,000 mg/m2 intravenously per day for 5 consecutive days in continuous infusion versus cisplatin (CP) 100 mg/m2 on day 1 plus 5-FU as described on days 2 to 6. In both arms, treatment was recycled every 4 weeks. Both groups were well balanced for age, sex, colon or rectal origin, median time between diagnosis to advanced disease, performance status at entry, and visceral involvement. The overall response rate in the combination and in the single arm were 18 and 23%, respectively. There were no differences in time to progression (a median of 17.8 and 14.9 weeks for CP-5-FU and 5-FU, respectively) and in overall survival (a median of 71.2 and 59.6 weeks, respectively). The incidence of grade 3-4 emesis was significantly higher in the CP-containing chemotherapy (p = .00001). Our study has failed to demonstrate any clinical benefit from adding cisplatin to 5-FU in patients with cancer of the colon and rectum. 相似文献
1000.