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991.
Disposition of tacrolimus in isolated perfused rat liver: influence of troleandomycin, cyclosporine, and gg918. 总被引:4,自引:0,他引:4
The disposition of tacrolimus and the influence of cyclosporine, troleandomycin, and GF120918 (GG918, or N-[4-[2-(1,2,3,4-tetrahydro-6,7-dimethoxy-2-isoquinolinyl)-ethyl]-phenyl]-9,10-dihydro-5-methoxy-9-oxo-4-acridine carboxamine) on its hepatic disposition were examined in the isolated perfused rat liver. Livers from groups of rats were perfused in a recirculatory manner following a bolus dose of tacrolimus (100 microg), a substrate for P-glycoprotein (P-gp) and CYP3A, or with felodipine (200 microg), a substrate only for CYP3A. Perfusions of each substrate were also examined in groups of rats in the presence of the inhibitors: troleandomycin (20 microM, CYP3A inhibitor), GG918 (1 microM, P-gp inhibitor), or cyclosporine (10 microM, CYP3A and P-gp inhibitor). In all experiments, perfusate and bile were collected for 60 min. Tacrolimus, felodipine, and their primary metabolites were determined in perfusate and bile by liquid chromatography/tandem mass spectrometry. The area under the curve (AUC) from 0 to 30 min was determined. For the dual CYP3A and P-gp substrate, tacrolimus, AUC +/- S.D. was decreased from control (2,260 +/- 430 ng. min/ml) by GG918 (1,730 +/- 270 ng. min/ml, P < 0.05) and was increased by troleandomycin (5,200 +/- 2,470 ng. min/ml, P < 0.05) and cyclosporine (4,390 +/- 2,080 ng. min/ml, P < 0.05). For the exclusive CYP3A substrate, felodipine, AUC was unchanged from control by GG918 but increased by troleandomycin and cyclosporine. It is concluded that GG918 increased the hepatic exposure of tacrolimus by inhibiting the canalicular P-gp transport, whereas GG918 has no effect on hepatic disposition of felodipine. These results support our hypothesis that the hepatic metabolic clearance of a dual substrate will be increased by inhibiting the efflux transporter. 相似文献
992.
993.
为了提高对胃平滑肌肿瘤的认识,作者回顾性分析了20例经手术、病理证实的胃平滑肌肿瘤的钡餐造影所见。结果表明,胃底与胃体上部是胃平滑肌肿瘤的病变高发区。本病具有典型胃粘膜下肿瘤的X线特征,腔内型者可见胃内边缘光滑的充盈缺损或软组织肿块,粘膜展平或推移;腔外型者可见突出胃外肿块或/和胃与邻近脏器受压;腔内外型者具有上述双重特征,肿瘤较大者多有溃疡形成,甚至囊变,根据肿瘤的大小、形态、生长类型及溃疡表现可作良恶性鉴别。本病的术前诊断主要依靠X线钡餐检查,但无胃肠压迫的腔外型肿瘤,钡餐则难以发现,CT或选择性血管造影可助诊断。 相似文献
994.
浙江医科大学附二院门诊处方中精神药物使用调查 总被引:1,自引:0,他引:1
本文对浙江医科大学附属二院1993年7月间31378张合格处方进行统计分析,并用限定日剂量(DDD)和药物使用指数(DUI)为指标,分析镇静催眠药物使用情况。结果表明苯二氮 类药方2067张,占总处方量的6.59%,巴比妥类药方49张,占0.16%,麻醉药方111张;占0.35%。苯二氮 类药方中.女性处方量1202张,男性处方量865张,男、女组间比较有显著性差异。苯二氮 类药方多分布在神经内科,常用的药有舒乐安定和阿普唑仑。九种常用的苯二氮 类药和麻醉性镇痛药的DUI均小于1。提示药物滥用现象少见,该院对这类药物的管理比较严格。麻醉性镇痛药中二氢埃托啡处方占67.57%。 相似文献
995.
Summary Based on the gate-related receptor hypothesis, an analysis of kinetics of AN-132, a new antiarrhythmic agent, blockade of
cardiac sodium channels and the gate-related receptor which is bound by the drug was performed by computer simulation. Model-predicted
apparent rates of onset of AN-132 (30 μmol/L) blocking were 0.051, 0.038, and 0.034 AF−1 at stimulation frequencies of 1.0, 2.0 and 3.0 Hz, respectively. The time constant of recovery from block by AN-132 at resting
potential -90 mV was 39.5 s. These findings are in agreement with those experimental data documented. The analysis of gate-related
receptor shows that AN-132 binds the inactivation gate-related receptor, and the binding and unbinding are modulated by the
inactivation process. 相似文献
996.
Lung function, smoking, age and mortality data in 158 adult severe alpha1-antitrypsin deficient, PiZZ individuals, followed from 1963 to 1982 were analyzed. Low initial FEV1 value was significantly associated with increased mortality (p < 0.005). A 3 yr mortality rate of 40% was found in individuals whose initial FEV1 values were less than 30% of that predicted. In contrast, the corresponding 3-yr mortality among those whose initial FEV1 values were between 30 and 65% of that predicted was only 7%. Smokers were found to have significantly lower FEV1 levels (p = 0.008) and higher mortality (p < 0.005) than non-smokers. The difference between current and ex-smokers in mortality and FEV1 level were not statistically significant (p = 0.9 and p>0.25, respectively). Cross-sectional analysis of the initial FEV1 values indicated a significant decline (p < 0.005) of FEV1 with increasing age. This decline was greater among smokers than non-smokers. Longitudinal analysis of FEV1 rates of decline in 80 cases with follow-up FEV1 measurements failed to detect any significant differences between smokers and non-smokers, but was performed late in the disease process. The application of these results to the planning of studies on replacement therapy, smoking intervention strategy and longitudinal follow-up is discussed. 相似文献
997.
以苏州七子山垃圾填埋场为背景,采用理论分析的方法,探讨山谷型垃圾填埋场合理的渗滤液收集系统的形式和定量计算方法。 相似文献
998.
Data Bank and Consulting System for Medical Management of Patiens with Acute Radiation Sickness 总被引:1,自引:1,他引:0
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Tang Zhongming Ye Genyao Mao Bingzhi Luo Qingliang Wang Guilin Liu Xiuwen Lin Ke Wu Dechang 《中华放射医学与防护杂志》1995,15(5):306-310
DataBankandConsultingSystemforMedicalManagementofPatienswithAcuteRadiationSickness¥TangZhongming;YeGenyao;MaoBingzhi;LuoQingl... 相似文献
999.
Zhen-yu Wu Laurent P. Rivory Michael S. Roberts 《Journal of pharmacokinetics and pharmacodynamics》1993,21(6):653-688
Distribution of Evans Blue (EB), sucrose, and water into the isolated perfused rat hindlimb was studied under various conditions using the multiple indicator dilution (MID) technique. Statistical moment analyses of the outflow profiles for the EB, sucrose, and water were used to define the vascular, extravascular, and total water spaces, respectively. The varied perfusion conditions included albumin content (2, 4.7, and 7%), temperature (25, 37, and 42 C), perfusate flow rate (2, 4, 8, and 12 ml/min) and the presence/absence of red blood cells. The range of studies undertaken were chosen to represent the variety of conditions used in the preparation of both isolated animal and human limbs, the latter being particularly important in cytotoxic therapy for recurrent malignant melanoma. The distribution volumes of EB, sucrose, and water were dependent on the flow rate and the albumin content of perfusate. The normalized variances (CV
2
) of the markers were of the following order: sucrose (2.18) > water (1.58) > EB (0.68), indicating that some disequilibrium occurs during the capillary exchange of water and sucrose. It is suggested that a Krebs-Henseleit buffer containing 2% BSA is a suitable perfusate for most studies of the isolated rat hindlimb perfusion. The effect of albumin concentration manifests itself only at higher flows.We acknowledge the support of the National Heart Foundation (Queensland) and the Mayne Bequest Foundation. This study was conducted while the investigator (Z.Y. Wu) was in receipt of a WHO Research Training Grant. Professor M. S. Roberts also acknowledges the support of the Queensland and Northern New South Wales Lions Kidney & Medical Research Foundation. 相似文献
1000.
阻断大脑中动脉建立大鼠局灶性脑梗塞模型的观察 总被引:4,自引:0,他引:4
通过经颅阻断大鼠大脑中动脉制成局灶性脑缺血动物模型。大脑中动脉阻塞后大鼠均出现各种神经病学征象。氯化三苯基四氮唑染色发现梗塞区位于皮质及基底节。光镜和电镜观察大脑中动脉阻塞后脑组织的病理改变,发现梗塞区不同程度的细胞和间质变性坏死。结果表明该模型是比较理想的局灶性脑缺血模型. 相似文献