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O’Beirne Sarah L. Chazen J. Levi Cornman-Homonoff Joshua Carey Bridget T. Gelbman Brian D. 《Lung》2019,197(6):727-733
Lung - Diaphragmatic paralysis (DP) is an important cause of dyspnea with many underlying etiologies; however, frequently no cause is identified despite extensive investigation. We hypothesized... 相似文献
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Summary Five different isolates of influenza C virus which were isolated over a period of 32 years and from four different continents were compared by RNA genome oligonucleotide fingerprinting analyses. The earliest isolate of influenza C virus was reported in 1949 byTaylor (19) and served as a reference strain for this study.The results obtained using this technique of comparing relatedness between viruses clearly showed that all strains are distinct. However, the similarities in the pattern of the oligonucleotide fingerprints are marked for the more recent virus isolates (1966–1979), whereas the reference strain C/Taylor shows more pronounced differences.The results are consistant with the high degree of serological crossreaction amongst influenza C viruses isolated over a long period of time, a property which sets this group of viruses apart from type A and B members of the orthomyxoviridae.With 3 Figures 相似文献
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Bridget A. Bagert 《Current neurology and neuroscience reports》2009,9(5):405-410
Recent seroepidemiologic and pathologic evidence suggests that prior infection with Epstein-Barr virus (EBV) may be necessary
for the development of multiple sclerosis (MS). EBV infects more than 90% of all humans, most of whom remain healthy. In contrast,
99% of MS patients have evidence of prior infection with EBV. EBV infects resting B lymphocytes, immortalizing them into long-lived
memory B cells that survive largely undetected by the immune system in the peripheral circulation. MS patients show elevated
titers to EBV years before developing any neurologic symptoms. Postmortem pathologic analysis of brains of patients with MS
has revealed diffuse EBV-associated B-cell dysregulation in all forms of MS. Theories of pathogenesis of EBV in MS include
antigenic mimicry, immortalization of B-cell clones, and cytotoxic T-cell dysfunction against virally infected B cells. This
article reviews the existing evidence of the relationship between EBV and MS and considers the therapeutic implication of
this evidence. 相似文献
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Evidence of sustained skeletal benefits from impact-loading exercise in young females: a 3-year longitudinal study. 总被引:4,自引:0,他引:4
Jaana A Nurmi-Lawton Adam D Baxter-Jones Robert L Mirwald Jacki A Bishop Patricia Taylor Cyrus Cooper Susan A New 《Journal of bone and mineral research》2004,19(2):314-322
The skeletal effects from intensive exercise throughout puberty are undefined. Forty-five female gymnasts and 52 controls were studied over 3 years, including a heredity aspect. The effects of size, maturity, exercise, and diet were identified using a multilevel regression model. Results demonstrated sustained skeletal benefits resulting from exercise throughout all stages of pubertal development. INTRODUCTION: Weight-bearing exercise is beneficial for peak bone mass development. However, whether skeletal benefits achieved with exercise are maintained if training remains intensive throughout the pubertal years is not entirely clear. The influence of familial resemblance for bone mass remains undefined in physically active versus inactive children. The aim of this study was to investigate the long-term influences of impact-loading exercise on bone quantity and quality in young females after controlling for growth, maturation, and hereditary factors. MATERIALS AND METHODS: At baseline, 45 gymnasts (G) and 52 normally active controls (C) 8-17 years of age were recruited. Anthropometry, diet, physical activity, and quantitative ultrasound (QUS) were measured annually for 3 consecutive years. DXA scans of total body (TB) and lumbar spine (LS) bone mineral content (BMC) and density (BMD) were taken three times at 1-year intervals. A multilevel regression model was fitted, and the independent effects of body size, maturity, physical activity, and diet were identified over time. To assess heredity influences, 27 G mothers and 26 C mothers volunteered for cross-sectional measurements of anthropometry, QUS, and BMC/BMD. RESULTS AND CONCLUSIONS: Gymnasts were smaller and lighter (as were their mothers) than controls, but they had significantly higher QUS and axial and appendicular BMC and BMD, with > 170 g more bone mineral in TB across puberty (after adjustment for maturity [years from peak height velocity], height, weight, energy, and protein intake). Gymnasts had up to 24-51% higher BMC and 13-28% higher BMD, depending on skeletal site. These results provide evidence of sustained skeletal benefits from impact-loading exercise, which are unlikely to result entirely from heredity, throughout pubertal years. 相似文献
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Comparisons of air and liquid personal cooling for intermittent heavy work in moderate temperatures.
P A Bishop S A Nunneley S H Constable 《American Industrial Hygiene Association journal》1991,52(9):393-397
Personal microenvironmental cooling has been used to enhance safety and extend the work capacity of laborers wearing protective clothing. Previous studies of air and liquid cooling have used either very low work rates or high environmental temperatures. Emergency work tasks frequently require high work rates and occur in moderate ambient temperatures. The purpose of this research was to examine the efficacy of intermittent personal cooling during rest and to compare liquid and air cooling systems in subjects engaged in hard work. Fourteen volunteers wearing chemical protective clothing performed treadmill walking at a metabolic rate of 430 W for 45 min followed by a 15-min rest at a wet-bulb globe temperature of 25 degrees C. During rest, volunteers received either no cooling, air cooling, or liquid cooling. Both cooling systems partially alleviated heat strain and increased work time with the air system offering slightly more effective cooling. 相似文献
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