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31.
The conduct of in vitro and in vivo drug-drug interaction studies: a Pharmaceutical Research and Manufacturers of America (PhRMA) perspective. 总被引:12,自引:0,他引:12
Thorir D Bjornsson John T Callaghan Heidi J Einolf Volker Fischer Lawrence Gan Scott Grimm John Kao S Peter King Gerald Miwa Lan Ni Gondi Kumar James McLeod R Scott Obach Stanley Roberts Amy Roe Anita Shah Fred Snikeris John T Sullivan Donald Tweedie Jose M Vega John Walsh Steven A Wrighton 《Drug metabolism and disposition》2003,31(7):815-832
Current regulatory guidances do not address specific study designs for in vitro and in vivo drug-drug interaction studies. There is a common desire by regulatory authorities and by industry sponsors to harmonize approaches, to allow for a better assessment of the significance of findings across different studies and drugs. There is also a growing consensus for the standardization of cytochrome P450 (P450) probe substrates, inhibitors and inducers and for the development of classification systems to improve the communication of risk to health care providers and to patients. While existing guidances cover mainly P450-mediated drug interactions, the importance of other mechanisms, such as transporters, has been recognized more recently, and should also be addressed. This article was prepared by the Pharmaceutical Research and Manufacturers of America (PhRMA) Drug Metabolism and Clinical Pharmacology Technical Working Groups and represents the current industry position. The intent is to define a minimal best practice for in vitro and in vivo pharmacokinetic drug-drug interaction studies targeted to development (not discovery support) and to define a data package that can be expected by regulatory agencies in compound registration dossiers. 相似文献
32.
DPC4/Smad4基因是新近被鉴定的一个肿瘤抑制基因 ,其编码的DPC4/Smad4蛋白是TGF β信号传导通路中的重要传导蛋白 ,是TGF β配体、受体结合后后续信号传导的胞质递质 ,参与TGF β受体激活后的信号传导。DPC4/Smad4调控的下游目的基因有p2 1WAF1、uPA、PAI 1、VEGF、TSP 1。转化生长因子 -β(transforminggrowthfactorbeta ,TGF β)信号传导通路的配体、受体、胞内信号传导分子Smad蛋白及其调控的下游目的基因等组成一个肿瘤生长的负性调节 ,通路中任何一个元件的异常都可引起信号传导紊乱 ,导致肿瘤发生 相似文献
33.
儿童功能性消化不良与幽门螺杆菌感染的关系 总被引:7,自引:1,他引:7
目的探讨儿童功能性消化不良与幽门螺杆菌(HP)感染的关系。方法用ELISA法和胃液尿素酶试验检测163例功能性消化不良和54例健康儿童的HP感染情况。结果血清HP-IgG阳性申功能性消化不良组高于对照组(43.6%:14.8%,X2=14.7,p<0.01),尿素酶试验阳性率功能性消化不良组也高于对照组(15.3%:3.7%,x2=5.07,p<o.05)。内镜检查15例患儿中,慢性胃炎12例(占80%)。经抗HP治疗功能性消化不良症状消失。结论儿童功能性消化不良与HP感染相关,HP是该疾病的主要病因之一。 相似文献
34.
Different astroglial reaction between the vagal dorsal motor nucleus and nucleus ambiguus following vagal-hypoglossal nerve anastomosis in cats 总被引:1,自引:0,他引:1
The dorsal motor nucleus of the vagus (DMV) and nucleus ambiguus (NA) were both traced with horseradish peroxidase (HRP) retrograde labelling technique after vagal-hypoglossal nerve anastomosis (VHA). By light microscopy, reinnervation of the new target, viz. tongue skeletal musculature, by DMV and NA was established at 22 days postoperation (dpo) as shown by the neuronal labelling with HRP. Ultrastructurally, signs of retrograde degeneration occurred in some DMV and NA neurons between 3 and 25 days after VHA. The incidence of darkened dendrites, an early sign of dendritic loss, was more common in the DMV compared to the NA. Accompanying the neuronal alteration were drastic astrocytic reactions in the DMV, but not in the NA. Between 3 and 7 dpo, the astrocytes in the DMV showed extensively hypertrophied processes and by 22 dpo, the somata and dendrites of HRP-labelled DMV neurons, but not NA's, appeared to be delineated by the increased lamellar astrocytic processes. Such a feature was sustained throughout the remaining postoperative intervals up to 500 dpo. It is concluded that the DMV motoneurons being autonomic in nature are probably not conducive to the newly acquired target organ. Hence, the insulation of the regenerating DMV motoneurons by the astroglial ensheathment would be vital in the neuronal remodelling and reconstruction of the vagal-hypoglossal pathway. 相似文献
35.
上海市闵行区中小学生肥胖患病率调查 总被引:5,自引:1,他引:5
[目的 ] 了解上海市闵行区中小学生肥胖和超重患病率情况 ,为预防儿童肥胖制订防制策略及措施提供基础资料。 [方法 ] 普查区内共 40 3 10名中小学学生的身高体重。采用体重指数 (BMI)和身高别体重法同时评价调查对象的肥胖患病率。 [结果 ] 研究人群平均年龄 ( 12 .5 9± 3 .0 7)岁 ,总体BMI为 18.63± 3 .3 1,其中男性BMI高于女性。以BMI法为评价标准总体肥胖患病率为 2 .76%,超重患病率为 11.5 7%;以身高别体重法为参考标准则肥胖的患病率为 6.17%,超重的患病率为 6.76%,两种评价方法的总体患病率差异有极显著性。肥胖和超重患病率总体上呈现男高女低 ,并随年龄增加而逐渐减低。 [结论 ] 闵行区中小学生的肥胖总体患病率呈现随年龄的增高而逐渐降低趋势。中小学生超重比例较高 ,应及早制订防制策略及措施 ,减少肥胖发生 相似文献
36.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts. 相似文献
37.
逍遥散由当归、白芍、白术、茯苓、炙甘草、柴胡、生姜、薄荷组成,有疏肝解郁,健脾和营之功[1].后世医家在原方基础上加减化裁,广泛应用于临床各科.凡邪在半表半里者,出现肝郁脾虚之证,均可采用,以调其偏胜,扶其不足,使病去人安.笔者临床应用逍遥散治疗肝郁不舒、克伐脾土、脾失健运、气血失和而产生的各种皮肤疾患,收到较好的疗效. 相似文献
38.
39.
目的 研究金属烤瓷修复体制作过程中经常出现的问题及如何补救,探讨提高金瓷修复体修复工艺方面的问题。方法 收集并分析临床近5年制作的580例、共650件金属烤瓷修复体,归纳其在制作中出现的问题。结果 瓷裂及崩瓷18件,占2.76%:气泡15件,占2.31%;铸造缺陷11件,占1.69%;色泽不协调12件,占1.85%。结论 金瓷修复体的加工制作是一个复杂而细致的过程,与技工室制作、临床设计及牙体制备都有密切关系,其中任何一个环节的操作不当都可能导致修复体的失败。 相似文献
40.
Background:The findings on the effectiveness of platelet-rich plasma, ozone, and hyaluronic acid in the treatment of osteoarthritis of the knee are controversial, and the existing original studies and meta-analyses are mostly comparisons of a single joint cavity injection method, lacking direct and indirect comparisons of different drugs in the joint cavity. The lack of direct and indirect comparisons of different drugs in the joint cavity makes it difficult to have a clearer and more comprehensive understanding of joint cavity injection methods. In this study, the efficacy of platelet-rich, ozone, sodium hyaluronate, and combined knee cavity injections were compared directly or indirectly using a reticulated meta-analysis in this field, and the efficacy of treatment measures was ranked to provide more comprehensive and reliable evidence-based clinical evidence for the selection of knee cavity injections in osteoarthritis of the knee.Objective:To compare the effects of platelet-rich plasma, ozone, and sodium glassate injection interventions on the efficacy of osteoarthritis of the knee through reticulated Meta-analysis, and to comprehensively compare the clinical effectiveness of platelet-rich plasma, ozone, and sodium glassate injection joint cavity injection for the treatment of osteoarthritis of the knee.Methods:The PubMed, CBM, CNKI, VIP, and Wan-Fang databases were searched for information on the effectiveness of platelet-rich plasma, ozone, and sodium vitrate injection for the comparative treatment of osteoarthritis of the knee, with a search time frame of each database from the date of creation to July 20, 2021. Two investigators independently screened the literature, extracted data according to inclusion and exclusion criteria, and evaluated the quality of the literature in parallel. Statistical analysis was performed using Stata 16.0 software to compare the differences in the efficacy of each treatment measure using the ratio and 95% confidence interval as effect indicators and to rank the efficacy.Results:Thirty-three RCTs with 7003 patients with osteoarthritis of the knee were included, involving 5 therapeutic measures. Meta-analysis showed that the efficacy of platelet-rich plasma injection was superior to both ozone and hyaluronic acid therapies. Hyaluronic acid+ozone and platelet-rich plasma+hyaluronic acid were both superior to ozone and hyaluronic acid monotherapy. The differences in efficacy between hyaluronic acid and ozone compared with platelet-rich plasma were statistically significant, and the differences in efficacy between the 2 combination therapies (platelet-rich plasma+hyaluronic acid, hyaluronic acid+ozone) and the 3 monotherapies (platelet-rich plasma, ozone, hyaluronic acid) were statistically significant. Platelet-rich plasma+hyaluronic acid, hyaluronic acid+ozone compared with 3 monotherapies (platelet-rich plasma, ozone, hyaluronic acid) were statistically significant, except for the difference in efficacy with platelet-rich plasma, which was not statistically significant, indicating that this platelet-rich plasma+hyaluronic acid and Hyaluronic acid+ozone combination therapy was superior to monotherapy. Also, the efficacy of platelet-rich plasma was better than hyaluronic acid and ozone and the difference was statistically significant, indicating that platelet-rich plasma was more effective than ozone and sodium glass in the treatment of osteoarthritis of the knee in monotherapy.Conclusion:It is believed that in the course of clinical practice, hyaluronic acid+ozone or platelet-rich plasma+hyaluronic acid combination therapy or platelet-rich plasma therapy can be preferred for patients with osteoarthritis of the knee. 相似文献