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Respiratory syncytial virus (RSV) bronchiolitis is a very common infection in infants and, after the acute phase, a number of patients develop a reactive airway disease that lasts for years. Although the pathogenesis of the lung damage after RSV bronchiolitis is still largely unknown, previous studies suggest that leukotrienes may play an active part in it. The aim of this study was to measure leukotriene levels in the nasal lavage fluid (NLF) collected in infants during RSV bronchiolitis and 1 month later. Cysteinyl leukotrienes (Cys-LTs) and leukotriene B(4) (LTB(4)) were measured in the NLF of 22 infants with their first episode of RSV bronchiolitis and 16 healthy infants. A second NLF sample was collected to measure leukotriene levels 1 month after the acute disease. NLF Cys-LT levels were significantly higher in infants with RSV bronchiolitis than in healthy controls [950 pg/ml (285.5-2155.9) vs. 110.5 pg/ml (66.5-451.3), p = 0.01], and they remained so a month after the acute infection (p = 0.02). A subanalysis showed no difference in Cys-LTs concentrations, either between bronchiolitis infants with and without a family history of atopy, or between those with and without passive exposure to cigarette smoke. No significant difference was found between the LTB(4) levels measured in the bronchiolitis cases and the control children. Cys-LTs are significantly increased in the NLF of infants with acute RSV bronchiolitis, and remain so at 1-month follow-up, suggesting a possible role of these eicosanoids in the pathogenesis of the disease.  相似文献   
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Preschool children with autism and their normally developing peers were compared on the Stanford-Binet IV and Preschool Language Scale before and after 1 school year. Both measures showed that although the children with autism functioned at a lower level than their normally developing peers, the children with autism had narrowed this gap after treatment, making a nearly 19-point increase in IQ and an 8-point gain in language quotient. The IQ measure remained stable for the normally developing peers while their language showed a 7.73-point increase. The data support the notion that young children with autism can make very significant developmental gains.Special thanks to the parents and the children who participated in this study. Thanks also to Michael Alessandri, Jean Burton, David Celiberti, Nancy Gera-Moglia, Anne Nathan, and Lisa Kamean who assisted in the data collection process. We appreciate the cooperation of Alicia MacWright and Leisa Tomchek who taught two of the classes from which participants were drawn.  相似文献   
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Forty-seven patients with advanced and/or recurrent squamous cell carcinoma of the head and neck were treated with 10-ethyl-10-deaza-aminopterin (10-EdAM), a new analogue of methotrexate. The drug was given as a weekly i.v. bolus injection, starting at 80 mg/m2 with two dose increments of 10% if no toxicity was observed after two weeks. Only patients with tumors of the larynx, oral cavity, oropharynx and hypopharynx were included in the trial. Eighty-two percent of the patients had had prior surgery and/or radiotherapy. Forty-four patients were evaluable for response and toxicity. Five CR (12%) and five PR were obtained, yielding a response rate of 24% (CR+PR). The toxicity was similar to that usually seen with methotrexate; stomatitis and skin toxicity were rather pronounced. The data suggest that 10-EdAM has activity similar to that of methotrexate in patients with head and neck cancer.  相似文献   
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A knowledge of the alteration in the fibre type profile of paraspinal muscle associated with low back pain is essential for the design of successful rehabilitation programmes. In attempting to compare the muscles of patients with low back pain with those of controls, few previous studies have considered factors such as gender, age, and size of the subjects, each of which can potentially confound interpretation of the results. We obtained samples of lumbar paraspinal muscle during spinal surgery from 21 patients with low back pain and, using the percutaneous biopsy technique, from 21 control volunteers matched for gender, age, and body mass. The samples were subject to routine histochemicsl typcal analysis to determine characteristics of muscle fibre type. Compared with controls, the muscle of the patients had a significantly higher proportion of type-IIB (fast-twitch glycolytic) fibres than type- I (slow oxidatve) fibres. The mean size of a given fibre type did not differ between the patients and the controls. Consequently, the relative area of the muscle iccupied by type-IIB fibres was higher and that by type-I fibres Was lower in the patients. The patients had a greater number of muscle samples with more than 1% type-IIC fibres, and abnormalities that could be described as pathological were more marked in the patients than in the controls. In conclusion, the paraspinal muscles of patients who have low back pain display a more glycolytic (faster) profile; this can be expected to render them less resistant to fatigue.  相似文献   
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The effects of perceptions of risk on attitudes toward handicapped children were studied. Five hundred twenty two nonhandicapped children between the ages of 8 and 19 were assigned to one of four experimental conditions in a basic 2×2 (Risk×Interview) paradigm. Some subjects were assigned to a high risk condition whereby if they indicated they would like to be friends with a handicapped peer, they were told that they might actually have to befriend a handicapped youngster who was about to enter their class; other subjects were not told about any personal involvement with the handicapped child. In the Interview factor, about half the subjects were informed that their attitudes would be known to other group members, the other half of subjects were told their attitudes would remain private. The 2×2 paradigm was studied with children at three ages levels: 8–11; 12–15; 16–19. Results revealed three significant main effects, generally supporting the hypothesis regarding the effects of risk factors.  相似文献   
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