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Approaches to the management of adolescents and young adults with acute leukaemia were investigated by sending a questionnaire to hospitals identified as having diagnosed or treated patients aged 15-29 years. The responses demonstrated the types of hospital treating these patients, the haematologists' perceived practice for entry of patients to Medical Research Council (MRC) leukaemia trials and reasons for non-entry. Data were linked to MRC trials data to determine the proportion of patients aged 15-29 years at diagnosis in responding hospitals actually treated in MRC leukaemia trials in the 5 years preceding the questionnaire. Eighty-two per cent of haematologists stated that they entered patients 'always' or 'whenever possible' for acute myeloid leukaemia (AML) and 76% for acute lymphoblastic leukaemia (ALL), but actual entry rates from the study hospitals were 46% of 239 AML patients and 36% of 182 ALL patients. The reasons most commonly reported for not entering eligible patients to national leukaemia trials were clinician preference for one arm of an MRC trial, a regional study or non-trial protocol, and concern about workload and ethical approval.  相似文献   
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AIM: To measure total energy expenditure and body composition in small for gestational age (SGA) infants in order to investigate proposed hypermetabolism in such babies. METHODS: A cross sectional study of 52 SGA infants measured at 5 weeks of age was made, using existing data from appropriate for gestational age (AGA) infants as controls. The double labelled water technique was used to assess both total energy expenditure and body composition. RESULTS: Multiple regression analysis showed that expressing energy expenditure per kg fat free mass adjusts for body composition in infants of this age. The relation between total energy expenditure and fat free mass differed between the two groups. CONCLUSION: These data indicate that for a given fat free mass the total energy expenditure of SGA infants is greater than that of AGA infants. Such data should be taken into account when energy requirements for SGA infants are being considered.  相似文献   
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One hundred five patients were treated for slipped capital femoral epiphyses during the period from 1964 to 1976. Attempts were made to evaluate the differences in results of multiple pinning and open epiphysiodesis performed to treat this problem. Pinning in situ was performed in 61 hips, and open epiphysiodesis was performed in 33 hips. The average follow-up period was seven years four months for pinning in situ and six years seven months for open epiphysiodesis. The average slippage was 22 degrees for patients treated by pinning in situ and 30 degrees for patients treated by open epiphysiodesis. At follow-up evaluation 91.7% of the patients treated by pinning in situ had good or excellent results, as compared with 71.6% of the patients treated by epiphysiodesis. For the patients treated by pinning in situ, 5% had poor results, and 3.3% were considered failures. For the patients treated by epiphysiodesis, 3.4% had poor results, while 25% were considered failures. Pinning in situ is the treatment of choice. It is more predictable, has less complications, and provides better long-term results.  相似文献   
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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   
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