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排序方式: 共有2519条查询结果,搜索用时 15 毫秒
991.
992.
Nardi A Brillet PY Letoumelin P Girard F Brauner M Uzunhan Y Naccache JM Valeyre D Nunes H 《The European respiratory journal》2011,38(6):1368-1373
The objectives of this study were to compare the survival of sarcoid patients with pulmonary fibrosis with that of the general population and to determine the causes of death and the incidence of evolutive complications. This retrospective cohort included 142 sarcoid patients in radiographic stage IV (74 males; mean ± SD age 48.1 ± 12 yrs). Their survival was compared with that of the general French population, matched for the year and age at diagnosis of stage IV disease, sex and length of follow-up. Expected survival probabilities were calculated year-by-year on the basis of probabilities provided by official demographic data for France. Survival curves were based on the Kaplan-Meier method and compared using the log-rank test. During the follow-up period (7.1 ± 4.8 yrs), pulmonary hypertension (PH) was observed in 29.7% of cases and aspergilloma in 11.3%. Long-term oxygen therapy was required in 12%. Survival was 84.1% at 10 yrs, which was worse than for the general population (p = 0.013). 16 (11.3%) patients died from the following causes: refractory PH (n = 5), chronic respiratory insufficiency (n = 4), acute respiratory insufficiency (n = 2), haemoptysis due to aspergilloma (n = 1), heart sarcoidosis (n = 1), nocardiosis (n = 1) and unknown causes (n = 2). Survival is significantly decreased in stage IV patients. 75% of fatalities are directly attributable to respiratory causes. 相似文献
993.
994.
995.
Jeger A Favre G Lutz JM Stern M Usel M Rovo A Rischewski J Tichelli A Gratwohl A Halter J 《Bone marrow transplantation》2011,46(9):1240-1244
Late malignancies have been discussed as a potential risk for growth factor mobilized donors of hematopoietic stem cells. Little is known about the incidence and potential risk factors. This single center retrospective cohort study evaluated all HLA-identical sibling pairs with hematopoietic stem cell transplantation (HSCT) for a hematological malignancy, treated from 1974 to 2001 at the University Hospital of Basel. Three hundred eighteen pairs were identified, 291 donors (92%) could be contacted. Median observation time was 13.8 years (range 5-32 years). Sixteen (5%) donors had developed a total of 18 tumors, 17 recipients a secondary tumor. According to the age- and sex-adapted cancer incidence, 3.3 tumors in male and 6.8 in female donors were expected, 3 (relative risk (RR): 0.91, 95% confidence interval: 0.19-2.66) and 4 (RR: 0.58, 95% confidence interval: 0.16-1.48), respectively, were found in donors between 0 and 49 years. Between 50 and 69 years, 4.5 tumors in males and 4.8 in females were expected, 5 (RR: 1.11, 95% confidence interval: 0.36-2.59) and 6 (RR: 1.23, 95% confidence interval: 0.45-2.67), respectively, were observed. Tumors do occur in donors of hematopoietic stem cells at least at the rate as expected in a normal population; whether incidence exceeds expected rates needs to be determined in larger international cohorts. 相似文献
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997.
Trimoulet P Belzunce C Faure M Wittkop L Reigadas S Dupon M Ragnaud JM Fleury H Neau D 《HIV medicine》2011,12(8):506-509
Objectives
Data on the natural selection of isolates harbouring mutations within the NS3 protease, conferring resistance to hepatitis C virus (HCV) protease inhibitors (PIs), are limited for HIV/HCV‐coinfected patients. The aim of this study was to describe the natural prevalence of mutations conferring resistance to HCV PIs in HIV/HCV‐coinfected patients compared with HCV‐monoinfected patients.Methods
The natural prevalences of HCV PI resistance mutations in 120 sequences from HIV/HCV‐coinfected patients (58 genotype 1a, 18 genotype 1b and 44 genotype 4) and 501 sequences from HCV‐monoinfected patients (476 genotype 1 and 25 genotype 4), retrieved from GenBank as a control group, were compared.Results
Of 76 sequences from HIV/HCV genotype 1‐coinfected patients, six (7.9%) showed amino acid substitutions associated with HCV PI resistance (V36L, n=1; V36M, n=2; T54S, n=2; R155K, n=1). In 31 of 476 (6.5%) HCV genotype 1 sequences retrieved from the GenBank database, HCV PI resistance mutations were found. The difference was not statistically significant (P=0.6). All of the sequences from HIV/HCV genotype 4‐coinfected patients and those retrieved from the GenBank database had amino acid changes at position 36 (V36L).Conclusion
Our study suggests that the natural prevalence of strains resistant to HCV PIs does not differ between HCV‐monoinfected and HIV/HCV‐coinfected patients. Further studies on larger cohorts are needed to confirm these findings and to evaluate the impact of these mutations in clinical practice. 相似文献998.
Schizophrenia is a complex and heritable disorder. Nevertheless, molecular genetics of schizophrenia remains inconclusive. By developing the concept of endophenotype for the disorder, it is easier to define an association between a phenotype and genetic variants or physiopathological processes. Cognitive disorders could be useful endophenotypes for schizophrenia. For example, the val(158)/met COMT polymorphism has been associated with executive function or working memory. Therefore, several cognitive dysfunctions were proposed as endophenotypes and were investigated in the context of different genetic polymorphisms. Genome-wide association studies and epistatic studies demonstrated the complexity of the mechanisms underlying cognitive disturbance. However, meta-analysis remains inconclusive. Altogether, the study of endophenotypes is an attractive approach to solve the complex mechanisms causing schizophrenia vulnerability. Nevertheless, several limitations exist and include the lack of reproducibility, the discordant results between healthy subjects and patients, the exclusion of the many rare variants. 相似文献
999.
Cermolacce M Lazerges P Da Fonseca D Fakra E Adida M Belzeaux R Azorin JM 《L'Encéphale》2011,37(Z2):S117-S122
In social cognition, the notion of Theory of Mind (ToM) is widely studied among people with schizophrenia to give an account for intersubjective disturbances. ToM is classically defined as the ability to make inferences about other persons'mental states, as beliefs, thoughts or intentions. However, ToM is not understood or explored as a homogeneous notion. First, this review briefly describes main theoretical models, as well as experimental tasks of ToM. Second, clinical results strongly suggest that patients with schizophrenia present impaired ToM performances. However, the presence of a robust relationship between ToM and schizophrenic symptomatology, or clinical course, is still controversial. Third, we highlight main findings from functional brain imaging studies based on ToM. Finally and in a more critical perspective, we suggest a few theoretical and experimental limitations regarding impaired ToM as a core feature of schizophrenic disturbances in social interactions. 相似文献
1000.
Schizophrenia is a complex illness whose mechanisms are still largely unknown. Functional brain imaging, by making the link between psyche and brain, has recently become an indispensable tool to study in vivo the neural bases underlying cognitive dysfunction in this disease. But despite the proliferation of data coming from this approach, the exact impact of functional imaging on our understanding of the disease remains blurry. In general, studies of the brain functioning of patients with schizophrenia found activation abnormalities which vary in nature and localization depending of the cognitive paradigm used. However, it appears that neurofunctional abnormalities observed in patients cannot be reduced to a simple well-localized deficit. It would be rather an alteration of the dynamics of the interactions between different brain regions that underlie the cognitive disturbances encountered in the disease. Functional brain imaging now offers new perspectives to clarify the dynamics of the brain networks, and particularly those involved in high-level cognitive functions, such as cognitive control or social cognition which seem to play a crucial role in the disease. The characterization of these features is an important issue not only to develop new hypotheses on the pathophysiology of the disorder, but also more pragmatically to identify potential therapeutic targets. 相似文献