A clinical and radiological two‐year follow‐up study of maxillary overdentures on osseointegrated implants

In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures.     

Progress toward re‐engineering non‐ribosomal peptide synthetase proteins: a potential new source of pharmacological agents

Many important pharmaceutical agents, including vancomycin, bleomycin, cyclosporin, and several antibiotics, are produced by non‐ribosomal peptide synthetase (NRPS) enzymes in microorganisms. The NRPS pathway produces an extensive library of products using multienzyme complexes acting in an assembly‐line fashion. Engineering an NRPS system to produce an even greater variety of products, some of which may also have beneficial therapeutic value, would be an enormous advantage. Several approaches have been successful in generating novel NRPS products: mutational biosynthesis during which nonnatural substrates are fed to an organism; domain and module swapping between different species to generate hybrid enzymes; and rational site‐directed mutagenesis, based either on phylogeny or computational prediction, intended to switch substrate specificity and produce altered products. This review will highlight the progress in these areas and describe research in the future that will extend the capacity for re‐engineering NRPS systems. Drug Dev. Res. 66:9–18, 2006. © 2006 Wiley‐Liss, Inc.     

Action Research: a valuable research technique for service delivery development

The evaluation of healthcare practice and service delivery is fraught with difficulties. Service development and / or delivery occurs within socially dynamic settings which are in a continual state of change. Service development also often involves large elements of improvisation. The action research approach is useful for health service research, as it supports collaboration between researchers and practitioners, and not only allows but makes explicit that the action researcher has both roles within the setting being studied. This paper discusses action research methodology and offers insight into principles that favor its use for service delivery development. This includes consideration of the interactive variables within studies of health care systems and the importance of evaluating relationships between stakeholders to understand how these factors or variables, which cannot be controlled for, are responsible for successful development of the service. Action research facilitates change and helps bridge the heory--practice gap. With the current dynamic changes within both the pharmacy profession and national health services, researchers may find the action research technique of value when considering new roles and innovative ways of engaging in collaborative, multi-disciplinary working to improve delivery of patient care.Accepted july 2004     

兔精原干细胞培养及生物学特征的初步研究

目的:建立精原干细胞的培养方法并对培养细胞的生物学特征进行研究.方法:用饲养层和无饲养层两种方法培养幼家兔精原干细胞,在倒置相差显微镜下观察培养细胞的生长和形态变化,并对细胞的糖原、脂质及c-kit受体的细胞化学和免疫细胞化学染色结果进行分析.结果:成功的分离并培养幼家兔精原干细胞.在培养细胞中精原干细胞为主体细胞,并可见少量间质细胞.根据精原干细胞体积大小和形态特点,可分为大、小两种类型.PAS染色,精原干细胞胞质呈阳性反应;免疫细胞化学染色显示,体积较小的精原干细胞c-kit受体呈强阳性反应,体积较大的大精原干细胞呈弱阳性反应;间质细胞PAS染色和c-kit受体染色呈阴性反应,而脂质染色呈强阳性反应.精原干细胞培养无论有无饲养层,均能呈集落状生长,但有饲养层的培养,细胞的生长明显优于无饲养层培养.结论:青春期前的睾丸生精小管是精原干细胞最集中、数量最多,且容易获取分离的部位;精原干细胞的成功培养为今后重建完整的生精细胞系的治疗性移植和对这类定向干细胞的发育及分化潜能的研究提供了细胞模型.     

螺旋CT及CAD技术在人工关节定制设计中的应用研究

随着生物医用材料研制和医学的迅速发展，以及生活水平、医疗保健、康复水平的提高，人们对自身组织、器官及骨骼缺损的修复和置换方面的要求日益提高，尤其对人造骨骼和人工关节的需求越来越广泛。由于计算机断层成像技术CT（computed tomography）已经成为显示和研究人体内部结构非常有用的手段，将计算机辅助设计技术CAD（Computer aided design）和计算机辅助工程CAE（Computer aided Engineering）等相关技术应用于人造骨骼和内置假体的设计，不仅可以提高产品的设计质量，同时，结合CT和计算机三维重建方法，     

Design and conduct of occupational epidemiology studies: III. Design aspects of case-control studies

Currently available approaches for the design of occupational case-control studies are reviewed. An accompanying paper reviews methods of analysis. We commence by drawing a distinction between cohort-based and registry-based studies. Methods for selecting cases and controls are then reviewed, including cumulative incidence and incidence density sampling, matching, sources of controls, and issues in control selection. Finally, the advantages and disadvantages of the case-control approach are summarized.     

Three-Dimensional Soft Tissue Prediction Using Finite Elements

Abstract Background and Aim: The prediction of soft tissue esthetics is important for achieving an optimal esthetic outcome in orthodontic treatment planning. Applicable procedures have so far been restricted to two-dimensional profile predictions that have not proven to be very reliable. The goal of this investigation was therefore to develop a novel finite element-based procedure that allows a three-dimensional, easily visualized, quantitative analysis and prediction of soft tissue behavior for the clinician. The procedure to be developed should be easy to handle and not entail any additional radiation exposure for the patient. Material and Methods: Using a three-dimensional scanner, the facial surfaces of 20 probands were digitalized and individual FEM models were generated. Results: After reduction of data redundancy via several conversion steps, a patient-specific simulation model was prepared consisting of 20,000 to 40,000 individual elements to which specific physical properties could be assigned. The average time required for generating a virtual model was 50 minutes. Problems occurring during model generation were rare (mainly shadowing phenomena and movement artifacts). Conclusion: The procedure outlined herein makes the reliable generation of patient-specific simulation models possible for facial soft tissue prediction in orthodontics.     

Estimated research and development costs of rotavirus vaccines

Diseases like rotavirus afflict both upper- and lower-income countries, but most serious illnesses and deaths occur among the latter. It is a vital public health issue that vaccines for these types of global diseases can recover research and development (R&D) costs from high-priced markets quickly so that manufacturers can offer affordable prices to lower-income nations. Cost recovery depends on how high R&D costs are, and this study attempts to replace high, unverified estimates with lower, more verifiable estimates for two new vaccines, RotaTeq (Merck) and Rotarix (GlaxoSmithKline or GSK), based on detailed searches of public information and follow-up interviews with senior informants. We also offer a new perspective on “cost of capital” as a claim for recovery from public bodies. Our estimates suggest that companies can recover all fixed costs quickly from affluent markets and thus can offer these vaccines to lower-income countries at prices they can afford. Better vaccines are a shared project between companies and public health agencies; greater transparency and consistency in reporting of R&D costs is needed so that fair prices can be established.     

Simultaneous versus sequential optimal design for pharmacokinetic-pharmacodynamic models with FO and FOCE considerations

We consider nested multiple response models which are used extensively in the area of pharmacometrics. Given the conditional nature of such models, differences in predicted responses are a consequence of different assumptions about how the models interact. As such, sequential versus simultaneous and First Order (FO) versus First Order Conditional Estimation (FOCE) techniques have been explored in the literature where it was found that the sequential and FO approaches can produce biased results. It is therefore of interest to determine any design consequences between the various methods and approximations. As optimal design for nonlinear mixed effects models is dependent upon initial parameter estimates and an approximation to the expected Fisher information matrix, it is necessary to incorporate any influence of nonlinearity (or parameter-effects curvature) into our exploration. Hence, sequential versus simultaneous design with FO and FOCE considerations are compared under low, typical and high degrees of nonlinearity. Additionally, predicted standard errors of parameters are also compared to empirical estimates formed via a simulation/estimation study in NONMEM. Initially, design theory for nested multiple response models is developed and approaches mentioned above are investigated by considering a pharmacokinetic–pharmacodynamic model found in the literature. We consider design for situations where all responses are continuous and extend this methodology to the case where a response may be a discrete random variable. In particular, for a binary response pharmacodynamic model, it is conjectured that such responses will offer little information about all parameters and hence a sequential optimization, in the form of product design optimality, may yield near optimal designs.     

芪月降脂片制剂处方的优化

[目的 ]优化芪月降脂片的制剂处方 .[方法 ]采用正交设计和多指标综合评分法对已筛选出的药剂辅料进行处方优化 .[结果 ]最佳制剂处方为糖粉 50 g ,辅料X 50g ,微晶纤维素 75g .[结论 ]该处方合理 ,成型性好