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71.
72.
Summary A system which can be used for injection or infiltration of large volumes of fluid is described. This consists of a syringe which fills automatically from a reservoir through an inlet/outlet valve.  相似文献   
73.
Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower C max, higher values of t max, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.  相似文献   
74.
孔令英  刘瑞波  王建辉 《中国骨伤》2007,20(12):833-835
目的:通过与4枚斯氏针固定比较,利用生物力学方法评价多枚空心钉固定股骨转子骨折的适应证和可靠性。方法:使用Sawbone股骨模型,模拟EvansⅢA型骨折,分别用2种多枚空心钉方法(矩外空心钉和矩内空心钉法)及多枚骨圆针固定,在CSS-11101力学实验机上进行载荷试验,取300 N载荷下股骨头垂直位移和张口位移数值,比较3种方法的轴向刚度。通过扭转实验比较3种固定方法的抗扭转能力。结果:3种固定方法在轴向刚度方面差异有统计学意义(P<0.05),而抗扭转能力方面差异无统计学意义(P>0.05)。结论:矩外空心钉固定力学性能相似于4枚骨圆针,而矩内空心钉固定弱于4枚骨圆针。应用多枚空心钉固定应选择稳定型股骨转子间骨折。  相似文献   
75.
目的评价靶控输注咪唑安定对靶控输注丙泊酚镇静催眠效应的影响。方法ASAI~Ⅱ级择期手术患者40例,随机分为四组:A组为单纯丙泊酚组,B、C、D组为丙泊酚 咪唑安定组,咪唑安定靶浓度分别为10、20、30ng/mL。咪唑安定达到平衡后,血浆靶控输注丙泊酚。记录丙泊酚效应部位浓度为1、2、3、4、5μg/mL时BIS值和OAA/S评分,并记录OAA/S评分达到4、3、2、1时丙泊酚效应部位浓度和BIS值,记录BIS值为50时丙泊酚效应部位浓度。结果1.咪唑安定达到平衡后,C组和D组BIS值显著下降;D组中OAA/S评分也显著下降,并低于B组和C组;2.随丙泊酚浓度升高四组患者.BIS值和OAA/S评分逐渐下降;3.相同丙泊酚浓度时,BIS值和OAA/S评分随咪唑安定浓度增加呈降低趋势;4.B、C、D三组患者OAA/S评分达到3、2、1以及BIS值达到50时所需丙泊酚效应部位浓度均显著低于A组,达到相同OAA/S评分D组所需丙泊酚效应部位浓度显著低于B组和C组。结论效应部位浓度为10、20、30ng/mL的咪唑安定均能显著降低丙泊酚靶控浓度,以达到需要的镇静深度;随咪唑安定浓度加深,降低作用越明显。  相似文献   
76.
Objective: The scientific quality of research is an important ethical issue. To clarify the quality of research projects in pharmacotherapy/pharmacology, 40 randomly selected research projects in pharmacotherapy/pharmacology submitted to a research ethics committee were reviewed. Results: Eight of the projects would not have contributed new knowledge nor were they necessary as controls for the results of previous research. Fifteen of the research protocols were of good quality, 15 could be used after revisions, and 10 were unfit for use. Eleven of the research projects were not finished 5 years after they were started. A written report was produced from 26 of the projects. Nine were of good quality and could be accepted for publication in a medical journal, 10 of the reports were in need of revision before publication, and 7 should not be accepted for publication. Conclusion: Research in this field ought to be improved, and ways to improve the standard of clinical trials in pharmacotherapy are dicussed. Received: 1 April 1996 / Accepted in revised form: 28 June 1996  相似文献   
77.
There is a scarcity of well-controlled studies of the seasonal variation in circadian rhythmicity. In the present study, the circadian phase of rectal temperature and the onset of slow wave sleep were studied in a series of twelve 24-h experiments, one each month of the year, for six healthy subjects under controlled conditions in a climatic chamber. In winter, as compared with summer, the average circadian rhythm of rectal temperature was phase delayed by 45 min, and the average onset of slow wave sleep was phase delayed by 40 min. The temporal relationship between the circadian phase of rectal temperature and the timing of slow wave sleep was maintained throughout the year. Habitual rising and retiring times covaried as well. Furthermore, the circadian rhythm of rectal temperature followed the timing of the photoperiod across the year, but had a much smaller range of seasonal variation. Apparently, the seasonal variation in the photoperiodic zeitgeber is largely compensated for by the stabilizing influence of secondary zeitgebers. However, in healthy subjects some effect of photoperiodic variation can still be observed.  相似文献   
78.
筛检对肝癌死亡率影响的研究   总被引:5,自引:0,他引:5  
5581名HBsAg阳性的男性随机分入周期性筛检组(A组,3712人)及对照组(B组,1869人)。A组(19155.4人年)共发生肝癌257例,B组(9785.5人年)为117例,两组的肝癌发生率分别为1342/10万与1196/10万;两组肝癌死亡分别为218与109例,肝癌死亡率分别为1138/10万与1114/10万。两组中Ⅰ期肝癌病例分别为29.6%与6.0%,差异有非常显著性意义。1、3、5年相对生存率A组为23.7%、7.0%、4.0%,B组为9.7%、4.0%、4.1%。用Poisson回归模型拟合显示,在调正年龄、初筛AFP及入列年份后,筛检对于肝癌的相对危险度为0.83,95%CI为0.68~1.03,有较弱的“保护”作用,Cox回归模型拟合结果显示当临床分期未引入模型时,筛检对于肝癌有显著的“保护”作用:危险率为0.6617,95%CI为0.5234~0.8365;而模型经调整后,危险率即接近“1”,95%CI为0.74~1.26。  相似文献   
79.
In the last few years, survival of patients infected with human immunodeficiency virus (HIV) has been improved because of a decreased incidence of some opportunistic complications attributable to prophylactic treatments and antiretroviral drugs. The impact of these agents should also be reflected in the quality of life (QoL) of patients. We have reviewed this topic with an emphasis on different types of measurements such as Q-TWIST, MOS and the Spitzer score which seem to be most appropriate for this patient population. We do not think that a special type of assessment should be designed for HIV-infected persons. It would be less time-consuming to improve already existing validated scores focusing on HIV infection. QoL in intravenous drug users with HIV should be evaluated more often.  相似文献   
80.
《Physiotherapy》1997,83(6):284-289
This paper describes a method of systematic reviewing. This method puts much emphasis on the methodological quality of the randomised clinical trials involved. Various items concerning the internal validity, precision and relevance of the studies are scored in such a way that next to the methodological quality the amount of uncertainty about it also becomes visible. These quality assessments are not only useful for systematic reviews, but also have an educational function for researchers with respect to the design and publication of a clinical trial.  相似文献   
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