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41.
42.
Noel Cameron 《American journal of human biology》1992,4(2):223-234
Analyses of the economic, political, demographic, and health indicators of South Africa place it within the context of the developing nations of the world. In particular current urbanization and population growth rates will lead to an increase of the Black urban population from 6.5 million in 1985 to over 20 million by the year 2000. Such dramatic social change will place major stress on the health of urban children. Few studies are available, however, that may be used to monitor the growth, and by implication the health, of rural children and thereby act as a baseline for the investigation of the effects of the urban environment. Research since 1985 on the growth and nutritional status of children has concentrated on longitudinal studies of rural children to form a basis for comparison to their urban counterparts. The results of these rural studies demonstrate growth patterns characteristic of children living in developing countries with some degree of variation, particularly with regard to weight and subcutaneous fat, between different rural groups. Rural children have a superior growth status in comparison to “average” urban children but are inferior to “well-off” urban children. The urban environment thus favors those children with adequate socioeconomic support but may be disadvantageous to children from “average” backgrounds. Interpretation of the effects of the rural environment will be greatly enhanced with information relating to nutritional intake and morbidity. 相似文献
43.
Low dose preoperative radiotherapy for carcinoma of the oesophagus: results of a randomized clinical trial. 总被引:9,自引:0,他引:9
S J Arnott W Duncan G R Kerr P R Walbaum E Cameron W J Jack W J Mackillop 《Radiotherapy and oncology》1992,24(2):108-113
One-hundred-and-seventy-six patients with potentially operable squamous cell carcinoma or adenocarcinoma of the middle or lower thirds of the oesophagus were randomly assigned to preoperative radiotherapy or surgery alone. Patients assigned to the radiotherapy arm received 20 Gy in 10 treatments over 2 weeks, using parallel opposed 4 MV beams. The preoperative radiotherapy was not associated with any significant acute morbidity or any increase in operative complications. The median survival of the overall group of 176 patients was 8 months, and the 5-year survival was 13%. There was no significant difference in the survival of the 90 patients who received preoperative radiotherapy and the 86 who were managed by surgery alone. Proportional hazards analysis identified lymph node involvement, high tumour grade and male sex as significant adverse prognostic features, but the treatment option assigned had no prognostic significance. It was concluded that low dose preoperative radiotherapy offered no advantage over surgery alone. 相似文献
44.
R M Leach C H Twort I R Cameron J P Ward 《Clinical science (London, England : 1979)》1992,82(1):55-62
1. The mechanical and pharmacological properties of small pulmonary arteries (100-300 microns normalized lumen diameter) were directly compared with those of the left main pulmonary artery (1-2 mm) from the rat. The active and passive length-tension characteristics and responses to a variety of agonists and antagonists were dependent on arterial diameter. 2. Maximum contractile function was obtained in both groups of vessels when stretched so as to give an equivalent transmural pressure of 30 mmHg. This is substantially lower than that found for systemic vessels, and reflects the normal low pulmonary arterial pressure. 3. Noradrenaline was a powerful vasoconstrictor in large but not small pulmonary arteries (P less than 0.001). In contrast, bradykinin produced a significantly greater response in the small arteries (P less than 0.001). In comparison with large pulmonary arteries, small arteries were more sensitive to noradrenaline (P less than 0.05) and 5-hydroxytryptamine (P less than 0.001), less sensitive to endothelin-1 (P less than 0.001) and had the same sensitivity to prostaglandin F2 alpha. 4. The mechanism that maintains the low arterial tone of the pulmonary circulation is unknown, but it may involve the release of relaxing factors from the endothelium. In this preparation, basal resting tone could not be demonstrated in either large or small arteries. 5. Acetylcholine-induced relaxation of pre-contracted pulmonary arteries was reduced or absent in the small artery, despite histological evidence of an intact endothelium. In large arteries pre-contracted with prostaglandin F2 alpha, acetylcholine (100 mumol/l) caused 88.2% relaxation compared with 25.2% in the small artery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
45.
Sherry M Bergeron Sheila Cameron Marjorie Armstrong-Stassen Karen Pare 《Revue canadienne de recherche en sciences infirmières》2006,38(2):42-54
The purpose of this study was to enhance our understanding of the influence of the SARS crisis on the work and personal lives of community nurses.A total of 941 community nurses employed in a range of health-care settings in the province of Ontario, Canada, provided qualitative information about their perceptions of the impact of SARS in their workplace and in their personal lives. Themes and subthemes from the data were organized into 2 categories: The Experience (operational, organizational, and personal narratives), and Learning from the Experience (opportunities for personal learning, professional and policy development, and insight into policy and administrative implications). The findings are discussed within a framework of the learning opportunity presented by the crisis at the local, national, and international levels. The roles of effective communication, emergency response coordination, and education are considered with respect to policy development and administrative responses to infectious disease protocol. The findings are particularly relevant at this time of heightened fear of global epidemics. 相似文献
46.
47.
48.
Michael R. Perkin David P. Strachan Hywel C. Williams Cameron T. C. Kennedy Jean Golding the ALSPAC Study Team 《Pediatric allergy and immunology》2004,15(3):221-229
We investigated the natural history of atopic dermatitis (AD) in a population-based birth cohort and assessed whether children at risk of visible eczema at 5 years of age can be identified from total immunoglobulin E (IgE) levels measured at 8, 12 and 18 months. AD data collected included a whole body examination for visible eczema at 49 months (4 years) and 61 months (5 years) of age and parent completed questionnaire data throughout their early lives. Children were divided into four groups based on their natural history of early AD: persistent (AD at 1, 6, 18, 30 and 42 months, n = 34), intermittent early onset (before 18 months of age, n = 495), intermittent late onset (18–42 months of age, n = 273) and unaffected ( n = 429). Visible eczema at 5 years of age was present in 12.2% (117/957) (95% confidence interval [CI] 10.1–14.3%) of the children. Levels of total IgE at 8, 12 and 18 months of age were associated with early onset of AD, but not with AD of later onset. For all four natural history groups, the geometric mean total IgE at 12 months was higher in those who subsequently had visible eczema than those who did not. However, the degree of overlap was such that total IgE at 12 months of age was a poor predictor of eczema at age five. A cutoff point of 78 kU/l had the highest positive predictive value for visible eczema at 5 years of age of 28.6%, with a sensitivity of 12% and specificity of 95%. 相似文献
49.
50.
Steven C. Cunningham M.D. Farin Kamangar M.D. M.P.H. Min P. Kim M.D. Sommer Hammoud Raqeeb Haque Anirban Maitra M.B.B.S. Elizabeth Montgomery M.D. Richard E. Heitmiller M.D. F.A.C.S. Michael A. Choti M.D. F.A.C.S. Keith D. Lillemoe M.D. F.A.C.S. John L. Cameron M.D. F.A.C.S. F.R.C.S. F.R.C.S.I. Charles J. Yeo M.D. F.A.C.S. Richard D. Schulick M.D. F.A.C.S. 《Journal of gastrointestinal surgery》2005,9(5):718-725
Gastric adenocarcinoma is the second leading cause of cancer death worldwide. In Western series, survival rates vary widely
and are generally lower than those reported from Eastern series. We performed a retrospective analysis of cases operated on
at the Johns Hopkins Hospital over the past 18 years and collected data on demographics, tumor characteristics, pathologic
stage, treatment methods, complications, survival time, and other relevant factors. Survival according to stage of disease,
Lauren tumor type, tumorlocation,time period, andadministration of adjuvant therapy wasanalyzed, andresultswerecompared with
those of other Western series. During this period, 436 patients with gastric adenocarcinoma underwent resection. We have shown
a statistically significant association between survival and margin status, stage of disease, and Lauren tumor type. Overall
5-year survival was 26%, and 5-year survival after R0 resection was 33%. No significant difference was detected between survival
and tumor location, time period of treatment, or administration of adjuvant therapy. Analysis of various Western series reveals
major differences between the cohorts under study, such as stage of disease, extent of resection, tumor type, and tumor location.
Many of the reported differences among Western series may be due to cohort differences, such as stage of disease, extent of
resection, tumor type, and tumor location. 相似文献