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排序方式: 共有10000条查询结果,搜索用时 746 毫秒
901.
C J Schilling I P Tams R S Schilling A Nevitt C E Rossiter B Wilkinson 《Occupational and environmental medicine》1988,45(12):810-817
Previous studies of respiratory disorders in workers exposed to pulverised fuel ash (PFA) have been confined to radiological effects that were found to be minimal. The present survey included 268 men (88% of the defined population) with a history of more than 10 years exposure to PFA in six power stations in the south east of England. Respiratory questionnaires with full occupational histories were obtained from all of these subjects, of whom 207 were actively employed and 61 had retired; 243 had lung function tests and 208 had chest x ray examinations. The men were grouped, using their occupational histories, into high, medium, and low exposure categories. Dust concentrations were obtained by personal sampling on a representative sample of men from the three exposure categories. Lung function tests showed that a modest effect on forced vital capacity, vital capacity, forced expiratory volume in one second, peak flow, and gas transfer (DCO) was associated with prolonged heavy exposure to PFA. The men with prolonged heavy exposure also showed higher prevalences of respiratory symptoms. No definite relation between exposure and x ray changes was established. The results of this cross sectional survey indicate that exposures to PFA should not exceed the limits recommended by the Health and Safety Executive for low toxicity dusts. 相似文献
902.
Disorders in the postnatal nervous, immune, and endocrine regulation systems were revealed in the progeny of rats irradiated
during the preimplantation period of embryogenesis. These disorders persist till adult age. The direction of disorders confirms
the hypothesis about memorization of changed proliferative properties of embryonal cells during the development of the (pro)endocrine
system of a new organism. Memorization results in distortion of postnatal nervous immunoendocrine regulation: hypertrophy
of the endocrine component and coadaptive underdevelopment of the nervous and immune components.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 164–166, August, 1998 相似文献
903.
Report of the Canadian Hypertension Society Consensus Conference: 2. Nonpharmacologic management and prevention of hypertensive disorders in pregnancy 总被引:5,自引:3,他引:2 下载免费PDF全文
J M Moutquin P R Garner R F Burrows E Rey M E Helewa I R Lange S W Rabkin 《Canadian Medical Association journal》1997,157(7):907-919
OBJECTIVE: To provide Canadian physicians with comprehensive, evidence-based guidelines for the nonpharmacologic management and prevention of gestational hypertension and pre-existing hypertension during pregnancy. OPTIONS: Lifestyle modifications, dietary or nutrient interventions, plasma volume expansion and use of prostaglandin precursors or inhibitors. OUTCOMES: In gestational hypertension, prevention of complications and death related to either its occurrence (primary or secondary prevention) or its severity (tertiary prevention). In pre-existing hypertension, prevention of superimposed gestational hypertension and intrauterine growth retardation. EVIDENCE: Articles retrieved from the pregnancy and childbirth module of the Cochrane Database of Systematic Reviews; pertinent articles published from 1966 to 1996, retrieved through a MEDLINE search; and review of original randomized trials from 1942 to 1996. If evidence was unavailable, consensus was reached by the members of the consensus panel set up by the Canadian Hypertension Society. VALUES: High priority was given to prevention of adverse maternal and neonatal outcomes in pregnancies with established hypertension and in those at high risk of gestational hypertension through the provision of effective nonpharmacologic management. BENEFITS, HARMS AND COSTS: Reduction in rate of long-term hospital admissions among women with gestational hypertension, with establishment of safe home-care blood pressure monitoring and appropriate rest. Targeting prophylactic interventions in selected high-risk groups may avoid ineffective use in the general population. Cost was not considered. RECOMMENDATION: Nonpharmacologic management should be considered for pregnant women with a systolic blood pressure of 140-150 mm Hg or a diastolic pressure of 90-99 mm Hg, or both, measured in a clinical setting. A short-term hospital stay may be required for diagnosis and for ruling out severe gestational hypertension (preeclampsia). In the latter case, the only effective treatment is delivery. Palliative management, dependent on blood pressure, gestational age and presence of associated maternal and fetal risk factors, includes close supervision, limitation of activities and some bed rest. A normal diet without salt restriction is advised. Promising preventive interventions that may reduce the incidence of gestational hypertension, especially with proteinuria, include calcium supplementation (2 g/d), fish oil supplementation and low-dose acetylsalicylic acid therapy, particularly in women at high risk for early-onset gestational hypertension. Pre-existing hypertension should be managed the same way as before pregnancy. However, additional concerns are the effects on fetal well-being and the worsening of hypertension during the second half of pregnancy. There is, as yet, no treatment that will prevent exacerbation of the condition. VALIDATION: The guidelines share the principles in consensus reports from the US and Australia on the nonpharmacologic management of hypertension in pregnancy. 相似文献
904.
E Grunfeld R Glossop I McDowell C Danbrook 《Canadian Medical Association journal》1997,157(8):1101-1105
The emphasis on home-based care is one important aspect of health services restructuring initiatives in Canada. Fundamental to the preference for home-based care over institutional care is the expectation that family caregivers will be available in the home to support patients who would otherwise be in an institution. The authors explore the potential impact of this devolution of services from institutions to the home in 2 vulnerable patient populations--elderly patients with dementia and elderly patients with terminal illnesses. Community-based surveillance strategies are needed to determine the true health, quality-of-life and economic outcomes of these restructuring initiatives. 相似文献
905.
We report a case of malakoplakia in association with colonic adenocarcinoma. Tumour-associated malakoplakia in the gastrointestinal tract is a rare finding, generally confined to the colon. It may be locally aggressive, with invasion of pericolic tissues, but is always located adjacent to the tumour. This contrasts with the often more diffuse, multifocal distribution of colonic malakoplakia in association with other pathologies. 相似文献
906.
907.
I. P. Naiker V. Chrystal I. G. Randeree Y. K. Seedat 《Postgraduate medical journal》1997,73(858):230-233
The prognostic importance of hypertension at the onset of clinical lupus nephritis is not well established. We studied retrospectively 44 patients with lupus nephritis in order to ascertain the prevalence of hypertension at presentation and to investigate a possible association between hypertension and renal functional impairment. A correlation was also sought between hypertension and histological class of lupus nephritis. Hypertension was graded as mild (diastolic 95-99 mmHg), moderate (100-114) or severe (> 115). Impaired renal function (creatinine > 120 mumol/l) was graded as mild (120-200 mumol/l), moderate (200-350 mumol/l), or severe (> 350 mumol/l). Histological class and the presence of hypertensive renal vascular lesions was recorded. The prevalence of hypertension was 38%. There were 17 hypertensives and 27 normotensives. The incidence of renal impairment was greater in the hypertensives, 47% vs 18.5% (p = 0.04). Mean serum creatinine was also higher higher in this group (p = 0.02). The presence of hypertensive renal vascular lesions identified a high-risk subgroup who had a higher incidence of renal functional impairment and worse renal function than the hypertensive group as a whole. Even at an early stage, hypertension and hypertensive renal vascular lesions correlated well with renal functional impairment. Aggressive treatment of hypertension is therefore essential in early lupus nephritis in order to prevent further deterioration of renal function as the disease evolves. 相似文献
908.
R. N. Sinha A. W. Patrick L. Richardson M. Wallymahmed I. A. MacFarlane 《Postgraduate medical journal》1997,73(859):293-294
One hundred insulin-dependent diabetic patients (age < 45 years, 53 smokers) were followed for six years. The age, duration of diabetes and mean glycated haemoglobin levels, were comparable between the smokers and non-smokers. Microvascular complications (retinopathy and increased urine albumin excretion) were commoner and more severe in the smoking group at six years, particularly in heavy smokers. Of the 45 original smokers reviewed at six years, 12 (27%) had stopped, six of whom had developed microvascular complications. Only two of the ''heavy'' initial smokers, likely to be at most risk, had stopped smoking, and three original non-smokers had started smoking. 相似文献
909.
910.