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61.
62.
Background Hospitalised medical patients are at significant risk of venous thromboembolic disease through fatal pulmonary embolism; low-molecular-weight heparins have been proved efficient in preventing deep venous thrombosis in surgical and medical patients, but their effect on mortality in bedridden medical patients remains unknown.Methods In a multi-centre, randomised, double-blind, placebo-controlled study, 2,474 consecutive patients aged over 40 years admitted to internal medicine departments in the last 24 h and unable to move alone were randomised to receive 0.3 ml nadroparin (7,500 anti-Xa units) or placebo for up to 21 days. The primary end-point was overall mortality at day 21.Results There were no significant differences between the patients characteristics. Overall mortality between the two groups was not statistically different [10.08% (124 of 1,230) versus 10.29% (128 of 1,244), respectively, in the nadroparin and in the placebo groups; relative risk reduction 0.02, CI (–0.27, +0.25), P=0.89]. An autopsy was performed in 123 of the 252 patients who died (49%). Pulmonary embolism was discovered at autopsy in 10 of 63 patients in the nadroparin group and in 17 of 60 in the placebo group [relative risk reduction 0.38, CI (–0.27, +0.70), P=0.13].Conclusion Nadroparin does not have a significant effect on mortality in bedridden medical patients, based on the study results. The study provides no data suggesting that low-molecular-weight heparins might reduce the incidence of thromboembolic in-patients hospitalised for an acute medical disease.The full list of investigators involved in the CY 216 study are given in Appendix A.  相似文献   
63.
We investigated the hypothesis that the subjective experience of orgasmic pleasure and satisfaction depends more on psychological and psychosocial than on physical factors. Male and female participants rated adjectives to describe orgasm attained during either solitary masturbation (n = 356) or sex with a partner (n = 442). Orgasmic pleasure and satisfaction were related more to (a) the cognitive-affective than sensory aspects of the orgasm experience; (b) the overall physical and psychological intensity of orgasm but not to anatomical location of orgasm sensations; and (d) relationship satisfaction. These findings emphasize the importance of psychosocial determinants of the orgasm experience.  相似文献   
64.
BACKGROUND: Hepatic veno-occlusive disease is a major limiting factor of high-dose chemotherapy in children. The cells lining the hepatic vascular endothelium express blood group A and/or B antigens according to the patient's blood group. We designed a study evaluating the impact of platelet concentrates containing ABO-incompatible plasma transfused to young children with a high risk of hepatic veno-occlusive disease. METHODS: In all, 186 consecutive children (median age: 4 years, range: 0.75-17 years), treated with high-dose chemotherapy containing busulfan followed by hematopoietic stem cell transplantation for neuroblastoma (n=112) or brain tumor (n=74) between 1988 and 1998, were investigated. The main endpoint was the occurrence of hepatic veno-occlusive disease. Multivariate analysis was performed using a Cox's regression model with transfusion of platelet concentrates containing ABO-incompatible plasma as a time-dependent covariate. RESULTS: We found that 73 out of 186 (39%) children developed hepatic veno-occlusive disease after transplantation. Multivariate analysis demonstrated that two factors significantly increased the risk of hepatic veno-occlusive disease occurrence: transfusion of platelet concentrates containing ABO-incompatible plasma (P=0.003) and use of melphalan in the conditioning regimen (P=0.006). Conversely, the number of platelet concentrates transfusions per week, child's age, weight, sex, and use of cyclophosphamide in the conditioning regimen had no effect. CONCLUSIONS: Transfusion of platelet concentrates containing ABO-incompatible plasma increases the risk of hepatic veno-occlusive disease in young children treated with a busulfan-containing regimen. Binding of A and/or B antigens expressed on the surface of hepatic endothelial cells may promote this complication. Transfusion of platelet concentrates containing ABO-incompatible plasma should be avoided in these children.  相似文献   
65.
The incidence of thrombosis--arterial and venous--increases with age. This is the case for atheromatous diseases, atrial fibrillation and even venous thromboembolic disease. Ischemic heart disease is the most common cause of death in the elderly. Atrial fibrillation, an independent risk factor for cerebral vascular accidents, affects around 10% of persons older than 80 years. The incidence of venous thromboembolic disease increases with age, reaching 12.5 per 1000 people older than 75 years, compared with 5 per 1000 aged 60-75 and 2.5 per 1000 aged 40-59. Elderly persons often have two or more cardiovascular or venous thromboembolic risk factors and thus a still higher risk of thrombotic events. Their risk of thrombosis justifies the systematic search for acquired risk factors to assess the level of risk and take appropriate prevention measures.  相似文献   
66.
BACKGROUND AND OBJECTIVE: Individual patient data meta-analysis consists in combining data from all available trials dealing with a therapeutic problem in order to increase the power of statistical analyses. A key issue when analyzing these pooled data sets is intertrial heterogeneity. In survival data, heterogeneity manifests itself either by differing treatment effects between the included trials or by a baseline hazard that differs between studies. One way to investigate and accommodate this heterogeneity is to use models that include random effects. METHODS: We apply this class of models to the Meta-Analysis of Chemotherapy in Head and Neck Cancers, in which strong heterogeneity is exhibited. This meta-analysis pooled 63 trials involving 10,741 patients. RESULTS: We show that such modeling permits a better understanding of heterogeneity in the MACH-NC data, both from a frequentist and from a Bayesian point of view. In particular, the modeling suggests the presence of two outlying sets of trials whose baseline risk could explain the apparent efficacy or inefficacy of some treatment protocols. CONCLUSION: We conclude that this family of random-effects models is a useful tool for exploring heterogeneity in meta-analyses of time-to-event data, and that its features can be applied to a very wide range of studies.  相似文献   
67.
A correction for short fourth metatarsal   总被引:1,自引:0,他引:1  
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68.
Multispectral analysis of magnetic resonance images   总被引:1,自引:0,他引:1  
Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.  相似文献   
69.
The aim of the study was to compare sleep patterns in children with epilepsy with those of their non-epileptic siblings and to determine which epilepsy-specific factors predict greater sleep disturbance. We conducted a case-control study of 55 children with epilepsy (mean age 10y, range 4 to 16y; 27 males, 28 females) and their nearest-aged non-epileptic sibling (mean age 10y, range 4 to 18y; 26 males, 29 females). Epilepsy was idiopathic generalized in eight children (15%), symptomatic generalized in seven (13%), and focal in 40 (73%); the mean duration was 5 years 8 months. Parents or caregivers completed the Sleep Behavior Questionnaire (SBQ) and Child Behavior Checklist (CBCL) for patients and controls, and the Quality of Life in Childhood Epilepsy (QOLCE) for patients. Patients had a higher (more adverse) Total Sleep score (p<0.001) and scored worse than controls on nearly all subscales of the SBQ. In patients, higher Total Sleep scores were correlated with higher scores on the Withdrawn, Somatic complaints, Social problems, and Attention subscales of the CBCL, and significantly lower Total Quality of Life Scores. Refractory epilepsy, mental retardation, and remote symptomatic etiology predicted greater sleep problems in those with epilepsy. We conclude that children with epilepsy in this current study had significantly greater sleep problems than their non-epileptic siblings.  相似文献   
70.
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