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91.
A 72-year-old man with increasing shortness of breath and atypicalangina pectoris received a chest radiograph 相似文献
92.
Salom El Hage Michle Ane Jean-Luc Stigliani Maynadier Marjorie Henri Vial Genevive Baziard-Mouysset Marc Payard 《European journal of medicinal chemistry》2009,44(11):4778-4782
In this paper we describe the design and synthesis of 18 derivatives of the antimicrobial atovaquone which were substituted at the 3-hydroxy group by ester and ether functions. The compounds were evaluated in vitro for their activity against the growth of Plasmodium falciparum, the malaria causing parasite. All the compounds showed potent activity, with IC50 values in the range of 1.25–50 nM, comparable to those of atovaquone and much higher than chloroquine or quinine. 相似文献
93.
94.
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
95.
Marc Tey Joan C. Monllau Josep M. Centenera Xavier Pelfort 《Knee surgery, sports traumatology, arthroscopy》2007,15(10):1235-1239
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
96.
Farida Daïkha-Dahmane Françoise Narcy Marc Dommergues Mireille Lacoste Agnes Beziau Marie-Claire Gubler 《Pediatric nephrology (Berlin, Germany)》1997,11(3):267-273
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
97.
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
98.
Practices of reading and writing: the constitutive role of the patient record in medical work 总被引:2,自引:0,他引:2
Marc Berg 《Sociology of health & illness》1996,18(4):499-524
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
99.
Marc C Chamberlain Andrew Sloan Frank Vrionis 《Journal of clinical oncology》2005,23(30):7750-1; author reply 7751-2
100.
Maya Koronyo-Hamaoui Eva Gak Daniel Stein Amos Frisch Yardena Danziger Shani Leor Elena Michaelovsky Neil Laufer Cynthia Carel Silvana Fennig Marc Mimouni Alan Apter Boleslav Goldman Gad Barkai Abraham Weizman 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2004,(1):76-80
The human small-conductance Ca(2+)-activated potassium channel gene KCNN3 has been involved in mechanisms underlying neuronal function and plasticity. A multiallelic CAG repeat polymorphism within the KCNN3 has been associated with schizophrenia and bipolar disorder. We have previously reported in a family-based study that longer CAG repeats are preferentially transmitted to patients with anorexia nervosa (AN). The present study extends the analysis of KCNN3 allele distribution to a larger series of AN female patients and control groups, incorporating information on ethnicity and co-morbidities associated with AN. The data analysis is presented while considering separately the two alleles of each individual, namely a minor (shorter) and a major (longer) allele. This study has found that the KCNN3 allele distribution in the general Israeli population does not differ significantly in at least four Jewish ethnic groups of Ashkenazi, North African, Iraqi, and Yemenite origin. These have been used as control groups in a matched case-control analysis that has demonstrated a significant over-representation of KCNN3 alleles with longer CAG repeats among AN patients (P < 0.001 for the major allele and P = 0.035 for allele sum). Under dichotomization, a significantly higher prevalence of the L allele (>19 repeats) has been observed among AN patients (P < 0.001). While considering AN and co-morbid phenotypes, a tendency towards longer (L) alleles has been observed in the subset of patients with obsessive-compulsive disorder (OCD) co-morbidity. These findings further implicate KCNN3 as a significant contributor to predisposition to AN. 相似文献