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71.
Bill J Gurley Ashley Swain Gary W Barone D Keith Williams Philip Breen C Ryan Yates Leslie B Stuart Martha A Hubbard Yudong Tong Sreekhar Cheboyina 《Drug metabolism and disposition》2007,35(2):240-245
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo. 相似文献
72.
End-systolic pressure-volume relations (ESPVRs) were analyzed in 10 closed-chest autonomically blocked dogs before and after volume loading that restored end-diastolic volume to its value measured in the control conscious state. Dogs had been previously instrumented with a left ventricular pressure micromanometer and ultrasonic crystals for measurements of major, anteroposterior, and septum-free wall diameters. Left ventricular volume was calculated with an ellipsoidal model in the left ventricular cavity. ESPVRs obtained during caval occlusion after volume loading were curvilinear as shown by the division of the relation into two parts. The initial part of the relation had a significantly smaller ESPVR slope (Ees, 12.0 +/- 1.8 mm Hg/ml) and ESPVR volume-axis intercept (Vd, - 3.5 +/- 0.8 ml) than the final part of the relation (19.5 +/- 3.1 mm Hg/ml and 0.0 +/- 0.6 ml, respectively, p less than 0.01). The end-diastolic volume-peak dP/dt relation showed a similar curvilinearity when end-diastolic volumes were larger than 1.5-1.7 times the minimal end-diastolic volume reached during caval occlusion. ESPVRs were not different during aortic constriction and caval occlusion when end-diastolic volume was small. In contrast, with large end-diastolic volumes, Ees and Vd were significantly smaller during caval occlusion than during aortic constriction. The final part of ESPVR (with small end-diastolic volume) had the same slope and intercept as that during aortic constriction. We conclude that preload produces a curvilinearity of ESPVR that significantly modifies derived indexes when the range of preload changes is large. 相似文献
73.
为运用循证医学方法对中药熏洗治疗膝骨性关节炎(OA)的临床疗效及安全性进行系统评价和Meta分析。全面收集了中药熏洗治疗OA的文献资料。在严格质量评价基础上,对研究结果进行定性分析。合并各篇优、良为阳性结果,中、差为阴性结果。利用RevMan4.1软件对多个研究结果的总体疗效进行固定效应模型的Meta分析,并进行敏感性分析。用漏斗图表示发表性偏倚。结果显示,中药熏洗治疗OA的效应值OR=2.68.95%可信区间为[1.82,3.95];敏感性分析显示效应值稳定;漏斗图图形不对称;无中药熏洗不良反应的报道。表明中药熏洗治疗OA有一定的疗效,由于漏斗图提示存在发表性偏倚,加上现有临床研究存在的方法学问题,现在的研究结论有一定的局限性,欲得出公认的结论,尚有待进行设计严谨的多中心、随机对照试验。 相似文献
74.
双利肝能显著降低慢性乙型肝炎患者血浆内皮素(ET)水平,使机体细胞免疫功能得以改善,血清乙肝病毒脱氧核糖核酸(HBV DNA)含量显著下降,延长疗程后,能否起到使HBV转阴的效果,有待临床进一步观察。本文观察连续给予双利肝胶囊24周喂养后,对大鼠产生的毒性反应及其恢复过程,为临床用安全剂量提供试验依据。 相似文献
75.
Rapid growth in biomedical research coupled with dramatic advancement in biotechnology has significantly improved our understanding of the molecular basis involving cancer development and progression. This improvement has led to the discovery of new molecular markers for cancer diagnosis and prognosis as well as new molecular targets for cancer treatment and intervention. Continuous emergence of some new developing area in molecular profiling, new therapeutic agents, tissue microenvironment and systems biology have made significant progress in clinical oncology. Clinical research and investigation that focus on these new developments have begun to show exciting results that indicate future promises in improving patient management and survival. 相似文献
76.
便秘是老年糖尿病患者的常见合并症之一.笔者自2006年6月~2007年6月以济川煎为基础方加味治疗老年糖尿病患者合并便秘24例,现报道如下.
…… 相似文献
77.
兔骨髓间充质干细胞Ⅱ型胶原表达的实验研究 总被引:1,自引:1,他引:0
目的探讨兔骨髓间充质干细胞表达Ⅱ型胶原的实验研究方法。方法利用β1转化生长因子腺病毒表达载体(Ad—TGFβ1)转染兔骨髓间充质干细胞(MSCs),观察转染后的Ⅱ型胶原表达。结果细胞转染后Ⅱ型胶原在免疫印记和免疫组化检测下均呈强阳性表达。结论Ad—TGFβI转染兔骨髓MSCs可使其细胞内Ⅱ型胶原表达阳性。 相似文献
78.
腹腔镜联合手术728例临床分析 总被引:8,自引:1,他引:7
目的探讨腹腔镜联合手术的优越性。方法回顾分析1992年7月~2006年3月开展腹腔镜联合手术728例临床资料,其中腹腔镜胆囊切除术(laparoscopic choleeysteetomy,LC)联合肝囊肿开窗引流术586例,LC联合阑尾切除术80例,Lc联合卵巢囊肿切除术46例,LC联合肾囊肿去顶引流术16例。结果726例在腹腔镜下完成手术,2例因腹腔粘连中转开腹,无胆道损伤、出血、感染、死亡等并发症发生。512例随访2~60个月,平均16个月,无胆道结石及肝、肾、卵巢囊肿复发。结论腹腔镜联合手术一次性处理两种或两种以上腹部病变是安全有效的,具有创伤小、痛苦轻、恢复快等优点。 相似文献
79.
关于医学生外科临床实习质量的探讨 总被引:2,自引:0,他引:2
外科是一门实践性很强的学科,如何培养实用型医学人才是摆在我们面前的首要问题。本文分析了外科临床实习中存在的问题,并提出一些应对措施。 相似文献
80.