A simulation study of three sequential methods for the comparison of two treatment groups when the response criterion is censored

Three recent sequential methods, group sequential analysis (GSA), the sequential probability ratio test (SPRT) and the triangular test (TT) are well suited to randomized clinical trials with a censored response criterion, as they do not require matched pairs of patients. We undertook a simulation study to investigate their statistical properties and to compare these three methods with the fixed-sample design. Our results suggest that the three methods have the expected statistical properties for size and power; they allow an important reduction of the average number of events before stopping, except with GSA when there is no treatment difference; the triangular test (closed design) appears the optimal design, as the variance of the number of events is smaller than with the sequential probability ratio test (open design) and analysis after every twenty new events does not alter the statistical properties of these sequential methods and enhances their usefulness.     

酶组化显示睾丸LDH－X方法的再探讨

对小鼠睾丸冰冻切片ＬＤＨ－Ｘ的显示方法作了进一步探讨。实验表明，以Ｌ－２－羟基－３－甲基戊酸（ＨＭＶ）为特异性底物，能相当有效地显示睾丸ＬＤＨ－Ｘ的分布，且该底物的配制方法简便易行。在显示ＬＤＨ－Ｘ的孵育液中采用萘酚蓝（ＮＢ）作中间递电子体较吩嗪甲基硫酸酯更具优越性。     

Codeine-induced histamine release in intact human skin monitored by skin microdialysis technique: comparison ofintradermal injections with an atraumatic intraprobe drug delivery system

Background The skin microdiallysis technique makes it possible to measure histamine release in intact human skin in vivo directly. In this study we have used the microdialysis technique to characterize histamine release by codeine after intracutaneous injectioin and following skin challenge by a novel atraumatic delivery technique. Objective The purpose of the study was to compare histamine release in human skin by codeine. delivered by an intraprobe drug delivery system (IPD) and intracutaneous injections (ICT), with respect to dose-response relations, kinetics of histamine appearance and decay, corelations between histamine release and skin respones, and reproducibility. Methods Hollow dialysis fibres were inserted intradermally in 12 healthy subjects. Twelve fibres were inserted in each subjects, six fibres in each arm. Each fibre was perfused at a rate of 3 μL/min, and samples were collected in 2 min fractions. By the IPD technique, codeine was administrered to the skin by adding codeine to the perfusion medium. Sequential IPD challenges were performed in one arm. and ICTs were done on the other arm. Results Sixfold serial dilutions of codeine (0.01-3 mg/mL) caused a significant doserelated histamine release by ICT and IPD. Peak histamine release was found within the first 4 min after skin challenge by ICT and IPD, followed by a fast decline with a dialysate histamine half life of approximately 2-3 min. Peak hisamine release was linearly correlates with cumulative release of the 20 min sampling period, and histamine release correlated with weal soze. The coefficient of variation on peak histamine releae was 18.9% and 4.8% for codeine ICT and IPD, respectively. Conclusioin We have described in detail codeine-induced histamine release in intact human skin in vivo by the microdialysis technique. It was possible to administer codeine atraumaticallyl to the skin by intraprobe delivery. The skin microdialysis codeine atraumaticallly to the skin by intraprobe delivery. The skin microdialysis technique opens up possibilities for measurement of infllammatory mediators release in normal and diseases skin, and it will be possible to deliver immunopharmacologically active drugsto the skin by intraprobe delivery.     

毛细玻管人体肿瘤干细胞集落形成检测

人癌干细胞集落形成测定常用双层琼脂平皿法。新法系采用园形玻璃毛细管法培养!可 以减少细胞用量及药物消耗。管内径为1.3mm,管长9.75cm,内盛15.000有核细胞/50μl,培养7～ 14天。50例肿瘤活检标本生长成功率为88％,并可供化疗药物敏感性试验用。这种微量化检测具有 独特的优点,便于推广应用。     

改良额颞-颞下窝入路切除中颅凹底内外沟通瘤

目的：为了更完全地切除中颅凹底内外沟通性肿瘤。方法：采用经过改良的Ｍｉｃｋｅｙ额颞颞下窝入路。其改良主要是将额骨瓣连同其表面附着的颞肌以及游离后的眶颧骨块一并向下翻开，并将手术程序作了相应改变。结果：成功切除了１３例肿瘤。术后３例恢复了轻工作，６例能自主生活，３例生活仍需别人照顾，１例复发未再次手术。结论：采用改良的额颞颞下窝入路对中颅凹底内外沟通性肿瘤暴露充分，切除广泛。Ｍｉｃｋｅｙ入路改良的优点：颞肌血运的保留，有利于骨瓣与正常颅骨的早期融合。同时颞肌附着点的保留，有利于咀嚼功能。     

A study of the value of electrophoretic and other techniques for typing Acinetobacter calcoaceticus

Forty-four isolates of Acinetobacter calcoaceticus var anitratus collected during hospital outbreaks were studied using polyacrylamide gel electrophoresis (PAGE), plasmid analysis, antibiograms and biochemical tests to determine their degree of similarity. Reproducibility tests were also carried out on the PAGE and biochemical techniques to determine their validity when used to compare bacteria of the same type isolated intermittently. PAGE data was analysed densitometrically and isolates compared using a similarity matrix. All methods were able to subdivide the isolates, but results did not always correlate well between methods. Reproducibility data indicated that careful attention to technique is required when organisms are examined by PAGE sequentially. Results suggest that no single biotyping technique is likely to be adequate and that electrophoretic, biochemical and antibiogram data may complement one another and other epidemiological data in the typing of these organisms.     

Local health services: some lessons from their evolution in Bolivia

Summary For a decade, numerous projects in Bolivia have tried to put in practice the concept of local health systems. But, so far, no significant changes have been made and local health services still are the 'poor relation' of the system. The main components of the project—expansion of health facilities, training of health personnel and institutional decentralization—were not designed to respond to the complexity of the problems encountered. Decentralization was implemented at the level of health districts but not accompanied by redefinition of functions at the central level, and challenged by civil servants' attempts to save their jobs. While training activities did introduce new methods and subjects, they were too often reduced to short workshops or seminars. Health facilities were built without regard for their significance beyond health care. A strategic approach is needed to adapt the planning process to the degree of liberty allowed by society.     

毛喉萜对人肝癌细胞增殖影响的实验研究

目的　探讨毛喉萜 (Forskolin)的抗肝癌作用。方法　采用克隆形成、MTT比色法观察毛喉萜对SMMC 772 1细胞的作用 ,并利用免疫细胞化学方法检测其对rasp2 1、p5 3蛋白表达的影响。结果　毛喉萜可明显抑制SMMC 772 1细胞的增殖 ,其抑制率与剂量呈正相关 (P <0 .0 1 ) ,经毛喉萜处理后 ,rasp2 1、p5 3蛋白表达均有明显下降。结论　毛喉萜能明显抑制肝癌SMMC 772 1细胞增殖 ,其作用可能与降低rasp2 1、p5 3蛋白表达有关。     

心理学研究中的科学方法与非科学方法

自心理学被界定为一门科学以来 ,对心理学的研究便十分强调研究方法的科学性。那些被认为是不科学的方法 ,如内省、思辨、假设、演绎等被长期排斥在主流心理学的研究方法之外。这虽是学科研究进步的表现 ,但也暴露出心理学研究中唯科学方法的缺陷。由于心理学研究对象的特殊性 ,非科学方法仍是心理学研究中的一种重要方法 ,心理学史上的一些重要成就表明了非科学方法的应用价值。心理学研究中的科学方法与非科学方法并不是对立的。人本主义心理学大胆引进非科学方法 ,兼收并蓄 ,其主张被越来越多的人接受。     

中心流形定理在非线性动力学系统分析和控制中的应用

本文将中心流形定理用于一类非线性动力学系统的局部定量分析和设计中,从而改进和简化了传统的分析和设计方法,弥补了线性化方法在处理这类系统方面的不足。