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71.
Bent H. Hellum Zhuohan Hu Odd Georg Nilsen 《Basic & clinical pharmacology & toxicology》2009,105(1):58-63
Abstract: The aim of this study was to evaluate in vitro the dose‐dependent induction potential of six commonly used trade herbal products on CYP2C19 and CYP2E1 metabolic activities in cultured human hepatocytes. S‐mephenytoin and chlorzoxazone were used as specific CYP substrates, respectively, and rifampicin was used as a positive induction control for both enzymes. The hepatocytes were exposed to herbal extracts in increasing and biological relevant concentrations for 72 hrs and CYP substrate metabolites were quantified by validated HPLC methodologies. The major findings were that St John's wort was the most potent CYP‐modulating herb, showing a dose‐dependent induction/inhibition of both CYP2C19 and CYP2E1, with induction at low dosages and inhibition at higher. Ginkgo biloba showed an induction/inhibition profile towards CYP2C19 which was similar but weaker than that observed for St John's wort. If cooperative mechanisms are involved is still an open question. Common sage induced CYP2C19 in a log‐linear dose‐dependent manner with increasing concentrations. Common valerian was a weak inducer of CYP2C19, while horse chestnut and cone flower were characterized as non‐inducers of CYP2C19. Only St John's wort showed an inductive effect towards CYP2E1. In addition to St John's wort, Gingko biloba and common sage should be considered as possible candidates for clinically relevant drug‐herb interactions with selected CYP2C19 substrates. 相似文献
72.
Qiong Xu Junqi Ling Gary S P Cheung Yan Hu 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(4):e109-e113
OBJECTIVE: The aim of this study was to evaluate the sealing ability of 4 different obturation techniques by using a glucose leakage test. STUDY DESIGN: Eighty extracted single-rooted maxillary incisors were selected for the study. The teeth were decoronated and the root canals prepared using ProFile rotary instruments to an apical dimension of size 40 (0.06 taper). The specimens were then randomly divided into 4 experimental groups (n = 15) and filled with gutta-percha and sealer by using either cold lateral compaction, warm vertical compaction, Thermafil, or the E & Q Plus system. Another 10 teeth each served as the positive and negative controls. A glucose leakage model was used for quantitative evaluation of the coronal-to-apical microleakage at 24 hours, 1, 2, 3, 5, 8, and 12 weeks. RESULTS: No significant difference in the cumulative amount of leakage was found among the 4 groups at 24 hours and 1 week (Kruskal-Wallis test, P > .05). Lateral compaction showed significantly more leakage than the other 3 techniques at longer intervals (Mann-Whitney U test, P < .008). No significant difference was found between vertical compaction, Thermafil, and E & Q Plus at all observation times. CONCLUSIONS: Warm vertical compaction, Thermafil, and the E & Q Plus system showed a better sealing result than cold lateral compaction of gutta-percha at extended observation periods. The glucose leakage method used in this study was able to provide a nondestructive, quantitative, and long-term evaluation of the sealing ability of root canal fillings. 相似文献
73.
pH值对IFN-α2b、rIL-2、ADM合用维拉帕米对人肝癌细胞杀伤作用的影响 总被引:1,自引:0,他引:1
目的 观察培养液在 pH值为 6 .8、7.3、7.6条件下rIL - 2、IFN -α2b、ADM及合用维拉帕米对人肝癌细胞 74 0 4杀伤作用的影响。方法 MTT法于 96孔培养板上进行杀伤实验 ,测定培养液pH值分别为 6 .8、7.3、7.6状态下 ,rIL - 2、IFN -α2b、ADM、及与维拉帕米联合杀伤人肝癌细胞 70 4 0的差异。结果 pH值为 7.6状态下rIL - 2、IFN -α2b、ADM及合用维拉帕米杀伤效果最佳。pH值为 6 .8、7.3、7.6时 ,IFN -α2b都能增加ADM抗肿瘤作用 ,但pH值为 7.6时 ,IFN -α2b +ADM杀伤效果最佳。结论 在偏硷性环境下 ,rIL - 2、IFN -α2b、ADM及合用维拉帕米对肿瘤细胞杀伤效果最佳 相似文献
74.
目的 探讨贫困地区超声乳化联合小切口硬核白内障摘除联合PMMA人工晶状体植入手术的疗效。方法 对336例(336只眼)Ⅳ级以上核白内障行超声乳化联合小切口晶状体摘除联合PMMA人工晶状体植入术。结果 术后1天、3天视力在0.5以上分别为240只眼(71.4%)、265只眼(78.8%)。术中主要并发症为后囊破裂。术后主要并发症为角膜水肿、眼压升高。结论 超声乳化联合小切口晶状体摘除治疗Ⅳ级以上核白内障切口小,术后反应轻,散光小,并且视力恢复快,费用低。手术技巧的提高可避免或减少术中术后并发症。 相似文献
75.
我们自2000年10月至2008年12月采用大承气汤加黄连应用与肛周常见疾病术后病人,治疗其术后大小便潴留,里急后重等症状,取得了满意的疗效,现报告如下. 相似文献
76.
8年间剖宫产率及指证变化的临床分析 总被引:3,自引:1,他引:2
近年来,我国各地的剖宫产率均呈明显的上升趋势,部分地区的剖宫产率甚至高达60%。居高不下的剖宫产率已引起了广大产科工作者和全社会的广泛关注。对我院近8年来剖宫产病例的临床资料进行回顾性分析,以寻求剖宫产率逐年上升的原因及探讨降低剖宫产率的途径与方法。 相似文献
77.
78.
Described in 1981 by the Chinese authors Yang Kuofan et al. [1] as a free flap, then in 1982 by Lu et al. [2] as a retrograde
flow pedicle flap, this fasciocutaneous flap is designed at the level of the anterior and external faces of the forearm, and
vascularized by the radial artery via a network of septal arteries. Prior to utilization it must be reversed on its distal
pedicle. This flap allows repairing cutaneous substance loss of the whole hand and fingers. The emergence of the Chinese flap
in the 1980’s resulted in a regression of the Mac Gregor groin flap that was widely used at this time [3,4]. Nevertheless,
other forearm flaps, less “expensive” in terms of vascular involvement [5–9] have reduced its indications. The Chinese flap
however keeps two essential indications: the multi-finger important defect that no other forearmflapmay cover; and composite
substance loss of the thumb (despite the fact that the Chinese flap shares these indications with interosseous artery composite
flaps). 相似文献
79.
80.
After a comprehensive rernew of the literature on syphilitic
aortitis, Longcope, (1) stated in 1913; ": . . . the presence of spiro:
chetes in these lesions, as might be expected, cannot by any means be
constantly demonstrated with Levaaiti stain. . . . . . . That these
organisms are ''Treponema pallidum seems almost certain thouS:h actual
proof of such by culture from the arterial lesions, a most difficult task,
or direct inoculation into animals, has not as yet been accomplished." 相似文献