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991.
Trends in body mass index in young adults in England and Scotland from 1973 to 1988. 总被引:2,自引:2,他引:0 下载免费PDF全文
STUDY OBJECTIVE--The aim was to determine whether the mean body mass index of young adults in England and Scotland had increased during the years 1973 to 1988. DESIGN--The study was an analysis of reported heights and weights for parents of children participating in a mixed longitudinal study of children's growth. SETTING--20 study areas (16 in England and four in Scotland) were selected by stratified random sampling. SUBJECTS--Subjects were parents of 5229 children who were new entrants to the study in the years 1973-6 and 1982-8. After excluding cases containing missing values on continuous variables, data for 4568 (87%) women (mean age 30 years) and 4029 (77%) men (mean age approximately 32 years) were analyzed. MEASUREMENTS AND MAIN RESULTS--Changes in weight for height over time were determined using body mass index as dependent variable, adjusting for age, social class, family size, and study area. In women, mean body mass index showed an annual increase of 0.10 (95% CI 0.03 to 0.17%) per year of study. Body mass index also increased with increasing age and family size and was greatest for women with husbands in manual occupations. The secular trend in body mass index in women was not explained by changes in the distribution of these variables. The proportion of women with BMI greater than 25 kg/m2 increased over the study period. In men the secular trend in body mass index was not quite significant in this age group [annual increase 0.05% (-0.01 to 0.12%)]. CONCLUSIONS--There has been an increase in the body mass index of young women in England and Scotland over the years 1973 to 1988. This increase was not explained by changes in the age, parity, social class of the subjects sampled. Evidence of a trend in men was not found. 相似文献
992.
George Rona 《Canadian Medical Association journal》1961,84(24):1386-1389
993.
The present case of PPMD is reported as an example of gastric outlet obstruction which did not produce overt symptoms until a lifespan of more than eight decades had elapsed; yet this lesion is considered to be congenital in origin. The clinical, radiologic and pathologic features of this entity were discussed, based on the present and other reported cases. Under clinical conditions in which the more usual causes of gastric outlet obstruction are not apparent, awareness of this anomaly may be of great significance in the management since simple excision of the membrane is curative. 相似文献
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996.
Diamond MP El-Hammady E Wang R Kruger M Saed G 《American journal of obstetrics and gynecology》2004,190(4):926-934
997.
Nigel?C?SmeetonEmail author Roberto?J?Rona Pamela?Dobson Ruth?Cochrane Charles?Wolfe 《BMC medicine》2004,2(1):27
Background
Within the UK there is considerable variation in the perinatal mortality rate. The objective of this study was to assess the factors associated with stillbirths and early neonatal deaths (ENND) and the suitability of the available databases in a health authority with one of the highest rates in the country. 相似文献998.
Apoptotic pathways in the brain may differ depending on cell type and developmental stage. To understand these differences, we studied several apoptotic proteins in the murine cortex and primary cultures of neurons and astrocytes of various ages in culture. We then induced apoptosis in our cultures using serum deprivation (SD) and observed changes in these apoptotic proteins. When analyzed by nuclear morphology and TUNEL staining, early cultures showed greater apoptotic injury compared with late cultures, and neuronal cultures showed greater apoptosis than astrocyte cultures. The decrease in apoptosis with development correlated best with a down-regulation of procaspase-3 and bax and decreasing caspase activation. Early culture astrocytes had higher caspase-11 levels compared with neurons. Mitogen-activated protein (MAP) kinases were also differentially expressed with activation of extracellular signal-regulated kinase (ERK) and p38 higher in early culture astrocytes and stress-activated protein kinase/C-jun N-terminal kinase (SAPK/JNK) greater in early culture neurons. However, caspase inhibitors, but not MAP kinase inhibitors reduced cell death. Our findings demonstrate that apoptosis regulatory proteins display cell type and developmentally specific expression and activation. 相似文献
999.
Measurement of carcinoembryonal (CEA) levels in pleural fluid are suggested to improve the unsatisfactory sensitivity of pleural cytology in the differential diagnosis of malignant pleural effusions. We evaluated simultaneously determined pleural and serum CEA levels in 117 patients with pleural effusions of different aetiology (74 malignant, 30 inflammatory exudates and 13 transudates) by use of an enzyme immunoassay (EIA). Despite considerable scatter, pleural levels of CEA in malignant effusions were significantly higher (p less than 0.001) than the values in benign effusions. Using a cut off level of 5 ng/ml, 41% (= sensitivity) of malignant pleural effusions showed elevated concentrations of CEA. Only one out of 43 benign effusions showed a level of 5 ng/ml, which is equivalent to a specificity of 98%. However, malignant effusions due to small cell lung cancer, pleural mesothelioma and metastasising ovarian carcinoma never showed elevated levels of CEA. Highest pleural values of CEA were observed in cases of alveolar cell or adenocarcinoma of the lung or metastasising breast cancer. Although pleural and serum CEA levels correlated significantly (rs = 0.77), the evaluation of serum CEA levels alone yielded a lower sensitivity (36%) and specificity (93%) than pleural levels. 77% of cases with malignant pleural effusions showing elevated pleural CEA levels were characterized by an increased ratio Pleura/Serum greater than 1, particularly in effusions due to lung cancer. The CEA ratio was significantly higher (p less than 0.05) in patients with malignant than with benign effusions. EIA appears to be more specific by avoiding false positive results in benign effusions as compared with determination by conventional RIA. In conclusion, evaluation of pleural CEA levels in patients with malignant effusions by using an EIA because of its high specificity is a valuable adjunct to pleural cytology in improving the diagnosis of malignant effusions. However, a normal CEA level in either pleural effusion or in serum is of no clinical significance. Simultaneous measurement in pleural effusion and serum is of greater value. 相似文献
1000.
National Study of Health and Growth: effect of change in design with reference to efficiency of mixed longitudinal studies for measuring trends. 下载免费PDF全文
The National Study of Health and Growth (NSHG) is a surveillance system which monitors the growth of primary school children in England and Scotland, set up in 1972 following changes in the school milk and welfare system. However, the study contained few children from inner city areas or ethnic minorities. In 1982 its design was changed from one in which the same areas were surveyed every year, to two separate systems with areas surveyed every two years, one set of areas corresponding to those in the original study, and the other set consisting of inner city and ethnic minority areas. The precision of the estimates of trends in height and weight for each system was smaller than that of the original system, but by less than 50%, so that an overall gain in information was achieved. Studies of mixed longitudinal design are shown also to be generally, but not always, less efficient for estimating trends than independent cross-sectional surveys obtaining the same number of measurements. 相似文献