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111.
112.
Analysis of count data from clinical trials using mixed effect analysis has recently become widely used. However, algorithms available for the parameter estimation, including LAPLACE and Gaussian quadrature (GQ), are associated with certain limitations, including bias in parameter estimates and the long analysis runtime. The stochastic approximation expectation maximization (SAEM) algorithm has proven to be a very efficient and powerful tool in the analysis of continuous data. The aim of this study was to implement and investigate the performance of a new SAEM algorithm for application to count data. A new SAEM algorithm was implemented in MATLAB for estimation of both, parameters and the Fisher information matrix. Stochastic Monte Carlo simulations followed by re-estimation were performed according to scenarios used in previous studies (part I) to investigate properties of alternative algorithms (Plan et al., 2008, Abstr 1372 []). A single scenario was used to explore six probability distribution models. For parameter estimation, the relative bias was less than 0.92% and 4.13% for fixed and random effects, for all models studied including ones accounting for over- or under-dispersion. Empirical and estimated relative standard errors were similar, with distance between them being <1.7% for all explored scenarios. The longest CPU time was 95 s for parameter estimation and 56 s for SE estimation. The SAEM algorithm was extended for analysis of count data. It provides accurate estimates of both, parameters and standard errors. The estimation is significantly faster compared to LAPLACE and GQ. The algorithm is implemented in Monolix 3.1, (beta-version available in July 2009).  相似文献   
113.
The purpose of this work was to describe the posterior ankle impingement syndrome related to the posterolateral tubercle of the talus bone and to present a retrospective analysis of our results after arthroscopic plasty of the tubercle in 15 ankles with a mean 3-year follow-up. Fifteen cases of posterior ankle impingement (PAI) underwent arthroscopic excision of an impinging bone spur. All the patients (13) were retrospectively evaluated at an average of 36 months after index surgery. There were seven women (bilateral in two of them) and six men. Ten were involved in different kinds of sport and three were professional ballet dancers. Preoperative symptoms included pain localized in the posterior ankle, limitation of motion, weakness and swelling. All patients had failed a course of conservative therapies. Surgery was performed through posterolateral and posteromedial portals as described by van Dijk. After soft tissue debridement, partial resection of the posterolateral process was performed until there was complete plantar flexion without bone impingement. Postoperatively, all patients followed the same rehabilitation protocol. Improvement in their impingement symptoms was recorded in all of them according to AOFAS score. One of them (7%) still had occasional discomfort. The results suggest that arthroscopic bone decompression of the posterolateral tubercle in cases of PAI resistant to non-surgical therapies is an effective treatment.  相似文献   
114.
Taxol is a potent stabilizer of microtubules, and inhibitor of in vitro replication, migration, and contraction of fibroblasts. It has been found to limit the development of experimental tractional retinal detachments in nonvitrectomized rabbit eyes. We used taxol in vitrectomized, phakic rabbit eyes with experimentally induced proliferative vitreoretinopathy and tractional retinal detachments. Taxol was dissolved in 30% DMSO because of poor aqueous solubility. A single 0.1 ml intravitreal dose of 2 × 10–4 M taxol in 30% DMSO was injected immediately after 250000 heterologous corneal fibroblasts had been injected; 0.1 ml of 30% DMSO was injected into control eyes. Taxol reduced the incidence of tractional retinal detachments seen 3–4 weeks later. When taxol injection was delayed for 3 days after the initial intravitreal injection of fibroblasts into nonvitrectomized eyes, the extent of retinal detachments was reduced, but the incidence of retinal detachment was unchanged from the untreated eyes at the end of 4 weeks. These data indicate that taxol may be most useful when given early in the course of proliferative vitreoretinopathy.Dr. Stewart Daniels was an Abe Meyer Fellow  相似文献   
115.
An alteration in cell/matrix interactions is one of the suggested mechanisms leading to cyst formation in polycystic kidney diseases. Most of these interactions are mediated by β1-integrins, a subfamily of integrin receptors, formed by the association of the β1-chain with different α-subunits. To date, no study on α-integrin subunit distribution during the early stages of cyst development has been reported. Using immunofluorescence, we analyzed the distribution of α-integrin subunits (α1, α2, α3, α5, and α6) and basement membrane proteins in kidneys of fetuses with autosomal dominant (ADPKD) or autosomal recessive polycystic kidney disease (ARPKD). The distribution was compared with that observed in normal fetal and post-natal kidneys, and in fetal cystic dysplasia and Meckel syndrome. Marked increase in α1-integrin staining was observed in normal and cystic collecting duct cells of both polycystic diseases (PKD), compared with normal and cystic controls. The distribution of integrin subunits α2, α3, and α6 was irregular in cyst epithelial cells of PKD and cystic controls. The increased expression of the α1-subunit specifically observed in PKD collecting duct cells may be an early consequence of the genetic defect in ARPKD. In ADPKD it parallels the reported expression of polycystin, the protein product of PKD1. The irregular expression of α2, α3, and α6 integrin subunits observed in all types of cysts suggests that cell/matrix interactions are altered early and may participate in the development of cysts, perhaps by contributing to the deregulation of cell survival in cystic diseases. Received May 28, 1996; received in revised form October 2, 1996; accepted October 25, 1996  相似文献   
116.
The case history is presented of a patient with squamous cell carcinoma of the lung with diffuse bilateral pulmonary shadowing mimicking bronchioloalveolar cell carcinoma which led to type I respiratory failure.  相似文献   
117.
Management of pregnancy and childbirth in England and Wales and in France   总被引:1,自引:0,他引:1  
This paper reviews national data on obstetric and neonatal practices in England and Wales, and in France between 1970 and 1980. The data have been derived from national statistics and surveys on national samples of births in 1970, 1975 and 1980 in England and Wales, and 1972, 1976 and 1981 in France. The analysis shows that there was no major difference in pregnancy outcome, but wide variations in medical practices, and their trend over time. The main differences were: in England and Wales a higher number of antenatal visits, a higher percentage of inpatient admissions during pregnancy, a higher rate of induction, more episiotomies, a higher rate of resuscitation at birth, and admission to neonatal special care units; in France, a higher rate of caesarean sections before and during labour, some evidence of a more active management of labour, and a longer hospital post-natal stay. These differences in practice reflect differences in objectives and assessment of the effectiveness of care between the two countries: they point out the need for better monitoring and evaluation of obstetric and neonatal practices.  相似文献   
118.
Tranexamic acid has been advocated for patients with severe bleeding tendency due to thrombocytopenia not responding to platelet transfusions. Macroscopic haematuria is a well-known contraindication for its use in such patients. We present three clinical cases with microscopic haematuria, in whom tranexamic acid caused problems of clot formation in the urinary tract, indicating that microscopic haematuria should also be considered as a contraindication for tranexamic acid.  相似文献   
119.
This paper contributes to a reappraisal of the sociological significance of the medical record. Building upon re-evaluations of the notion of ‘representation’ in ethnomethodological and science and technology studies, it attempts to portray the medical record as an artefact which mediates the social relations that act and work through it. Through practices of reading and writing, it is argued, the medical record figures as a fundamental, constitutive element of medical practice. To address some of the dimensions that are involved, three case fragments are discussed. The way the medical record enters into the process of ‘medical decision making’ in the doctor-patient interaction, and into that interaction itself, is discussed first. Subsequently, some aspects of how the record mediates medical work as it is performed in the wards of a hospital are outlined. A third instance of its prominent role demonstrates how practices of reading and writing tend to produce particular renderings of patients’ histories - including notions of how medical work is structured.  相似文献   
120.
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