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71.
采用HPLC测定健康志愿者血浆中头孢克洛的浓度。方法简便快速,结果准确。平均回收率为102.18±4.01%,日间及日内RSD均小于6%。血药浓度-时间曲线符合一室模型。  相似文献   
72.
目的:探讨乌苯美司对小鼠药物动力学及与实验性肿瘤转移治疗活性间的关系。方法:用放射免疫法测定小鼠在不同给药途径下的乌苯美司血清药物动力学及观察乌苯美司对黑色素瘤肺转移模型的治疗活性。结果:乌苯美司iv的T12较短,初始血药浓度较高。iv和im给药后的曲线下面积较大;po及ip则较小。不同给药途径对实验性肿瘤转移均有治疗作用。结论:乌苯美司的血清T12较短,其治疗活性取决于冲击和高剂量的给药方式。  相似文献   
73.
Summary The single- and repeated-dose pharmacokinetics of sabeluzole have been determined in six elderly patients with [senile] dementia of the Alzheimer type.After a single oral dose of 10 mg sabeluzole, the peak plasma concentration was attained at 1 to 4 h; it averaged 42 ng·ml–1. On repeated dosing (10 mg b. d.), steady-state was virtually attained after 3 days of treatment. Steadystate mean trough and peak plasma concentrations fluctuated between 53 and 94 ng·ml–1. The mean terminal half-life after a single dose and at steady-state was of the order of 33 h.Sabeluzole was well tolerated and at the end of treatment, no systematic changes in blood haematology, biochemistry or urinalysis were seen.  相似文献   
74.
氟罗沙星的体内外试验相关性研究   总被引:4,自引:1,他引:3  
本文研究了新型喹诺酮类药物氟罗沙星体外溶出与体内吸收之间的相关性。实验表明,本品口服吸收在血清中达峰时间较快,作用持久,消除半衰期为9.60hr。在人工胃液中溶出速率较快,在血清达峰之前,体内吸收与体外溶出量之间呈现良好的相关性。  相似文献   
75.
We report an adult female with a rare giant choledochal cyst. The patient presented following a normal pregnancy with the classical triad of an abdominal mass associated with jaundice and right upper quadrant abdominal pain. The cyst was excised using an intramural technique and biliary reconstruction achieved with a Roux-en-Y hepaticojejunostomy. Our patient has remained well with no evidence of malignancy over a 12 year review period. The aetiology and current management of this condition are discussed.  相似文献   
76.
A simulation study was conducted to compare the cost and performance of various models for population analysis of the steady state pharmacokinetic data arising from a one-compartment model with Michaelis-Menten elimination. The usual Michaelis-Menten model (MM) and its variants provide no estimate of the volume of distribution, and generally give poor estimates of the maximal elimination rate and the Michaelis-Menten constant. The exact solution to the Michaelis-Menten differential equation (TRUE) requires a precise analysis method designed for estimation of population pharmacokinetic parameters (the first-order conditional estimation method) and also considerable computational time to estimate population mean parameters accurately. The one-compartment model with dose-dependent clearance (DDCL), in conjunction with the first-order conditional estimation or Laplacian method, ran approximately 20-fold faster than TRUE and gave accurate population mean parameters for a drug having a long biological half-life relative to the dosing interval. These findings suggest that the well-known MM and its variants should be used carefully for the analysis of blood concentrations of a drug with Michaelis-Menten elimination kinetics, and that TRUE, in conjunction with a precise analysis method, should be considered for estimating population pharmacokinetic parameters. In addition, DDCL is a promising alternative to TRUE with respect to computation time, when the dosing interval is short relative to the biological half-life of a drug. This work was supported in part by the Epilepsy Research Foundation, the Nakatomi Foundation, and a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan.  相似文献   
77.
Summary The influence of treatment with ponsinomycin, a new macrolide antibiotic, on the pharmacokinetics of cyclosporin A has been studied in 10 renal transplant patients. The pharmacokinetics of cyclosporin A was investigated at steady state, before and during treatment with ponsinomycin.On average, the blood levels of cyclosporin A were doubled by the macrolide, possibly due to a decrease in elimination or/and to an increase in absorption.Ponsinomycin should be use very carefully in patients treated with cyclosporin A.  相似文献   
78.
The pharmacokinetics of a single oral dose of the neuroleptic drug zuclopenthixol (10 or 6 mg) was studied in 6 extensive and 6 poor metabolizers of debrisoquine. The peak plasma concentrations of zuclopenthixol did not differ between the phenotypes, whereas the plasma elimination half-life was significantly longer in poor than in extensive metabolizers (29.9 +/- 6.6 vs 17.6 +/- 6.9 h). Accordingly, the total oral plasma clearance was lower in poor than in extensive metabolizers (0.78 +/- 0.27 vs 2.12 +/- 0.65 1/h/kg). Ten of the volunteers had previously participated in a similar study in which the kinetics of perphenazine, another neuroleptic drug, were studied in poor and in extensive metabolizers of debrisoquine. There was a significant correlation between the oral clearance of perphenazine and that of zuclopenthixol among these 10 subjects. The study indicates that the disposition of zuclopenthixol, as well as that of perphenazine, is related to the genetically determined capacity to hydroxylate debrisoquine. The significance of this polymorphism for the clinical use of neuroleptics is discussed.  相似文献   
79.
Summary The absorption of almitrine from the upper gastrointestinal tract has been evaluated in 6 healthy volunteers by an intubation technique. Almitrine bismesylate dissolved in malic acid was introduced into the stomach after homogenization with a meal containing the marker14C-polyethylene glycol (PEG) 4000. Unlabeled PEG 4000 was infused into the second part of duodenum throughout the experiment. Samples of the luminal content were collected every 15 min for four hours from the stomach and at the ligament of Treitz. Blood was also collected.Almitrine was neither absorbed from nor metabolized in the stomach. About 37% of the quantity of drug emptied from the stomach was absorbed from the duodenum. Almitrine was detected in plasma 50 min after ingestion of the meal and its plasma concentration-time profile reflected the cumulative gastric emptying rate. The metabolite tetrahydroxy almitrine was found in intestinal samples as soon as unchanged drug was detected in plasma. The intraluminal rate of formation of the metabolite increased with time.The results suggest hepatic metabolism of almitrine followed by rapid excretion of the metabolite in the bile.  相似文献   
80.
Long-term results of cervical interbody fusion with PMMA were evaluated in a retrospective study. X-ray films of 83 patients were obtainable. Post-operative follow-up in this series was between 15 and 20 years. The results show that PMMA is engrafted after about 2 years. Stable vertebral interbody fusion is obtained in about 90% of cases. Development of malignoma was not observed. Resorptive bone alterations, which can be seen in about 2% of cases one to two years after operation are shown not to be progressive. This process heals and stable fusion develops.  相似文献   
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