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1.
A cross-sectional study of tobacco-smoking habits in a random sample of 976 coloured subjects aged 15-64 years revealed that smoking was common, 57% of men and 41% of women being current smokers and 10.4% of men and 9.6% of women having stopped smoking. Heavy smoking prevailed, indicating by mean daily consumption of 14.2 and 13.1 cigarettes among male and female smokers respectively; only 33.5% of male and 39.6% of female smokers used less than 10 cigarettes per day. Coloured smokers smoked more heavily during the weekend. Both men and women smoked mostly filter cigarettes. Forty-four per cent of male and 49.5% of female smokers stated that they had attempted to stop smoking, mainly for health reasons. More than one-third of the participants had a positive attitude to combating smoking, particularly those with an educational level higher than Standard 7. Former smokers and heavy smokers had a significantly higher prevalence of ischaemic heart disease than the other participants. Smoking was associated with a low body mass index, low high-density lipoprotein cholesterol levels, low socio-economic standing, high alcohol consumption and type A coronary-prone behaviour in men. In 1982 the economically active coloured population of the Cape Peninsula spent an estimated R36.2 million on cigarettes.  相似文献   
2.
The differences in site and degree of atherosclerotic involvement of various vascular beds and their clinical significance are emphasised in a study of 304 black stroke patients. Detailed clinical examinations, computed tomography (CT), gated blood pool studies, echocardiography and ECG were performed and autopsy studies carried out. CT of the brain showed that non-haemorrhage, i.e. ischaemic lesions, accounted for 71.2% of strokes, a similar figure to that found in white stroke patients. However, carotid bruits (0.62%) and peripheral vascular disease (0.9%) followed by transient ischaemic attacks (1.9%) were found to be uncommon. Similarly, ischaemic heart disease (6.9%) appeared to be less common than the incidence in reported white stroke patients. In 30 patients who came to autopsy, the maximum degree of atherosclerotic stenosis of the extracranial carotid arteries was 21.7% of the lumen diameter. The differences in the site and degree of atherosclerosis in blacks not only give rise to differences in the clinical features of stroke patients but may have an important bearing on their investigation, management and prognosis.  相似文献   
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Summary Parental care was analyzed separately with the PBI for both father and mother or their surrogate to assess its association with suicidal behavior (attempt or serious ideation). The study was conducted on two French-speaking samples from Montreal: the first included 2,327 high school students and the second 701 young adults (18 to 24) reached by phone. Results showed poor care of father to be highly associated with suicidal behavior in the highschool group. Poor care of the mother and parental divorce obtained a lower association. In the second sample, only poor care of the father was significantly associated with suicidal behavior. The conclusion is that more attention should be focused on the father and that parental divorce may have a short-term effect but not a lasting influence when poor care is absent.  相似文献   
5.
Coronary heart disease (CHD) is still relatively uncommon in the black population of South Africa. We embarked on a study to determine the prevalence of risk factors leading to CHD in the black population of Durban. The study sample was selected from patients attending a dental clinic at a hospital. A total of 458 patients (age range 16-69 years) was studied. The prevalence of CHD was 2.4%. The percentage prevalences of selected risk factors were: hypertension (blood pressure > or = 140 mmHg systolic and/or > or = 90 mmHg diastolic) 28% (31.9% for males, 25.4% for females); protective levels of high-density lipoprotein/total cholesterol > or = 20%, 81.3%; diabetes mellitus 4.9% for males, 2.9% for females; smoking > or = 10 cigarettes per day 28.1% for males, 3.4% for females; obesity 3.7% for males 22.6% for females. We found the Minnesota Coding System for electrocardiographic changes of CHD and the Rose questionnaire to be unreliable for eliciting CHD in blacks. Hypercholesterolaemia is less common, and this may explain the low incidence of CHD in blacks. Epidemics of CHD as seen in Indian, coloured and white South Africans can still be prevented in the black population, but preventive measures must be instituted rapidly.  相似文献   
6.
Twenty-four hour urinary free cortisol and mean and integrated 13h00-16h00 plasma cortisol levels were measured in 9 patients with proven Cushing's syndrome (5 with Cushing's disease, 2 with ectopic adrenocorticotrophic hormone production due to bronchial carcinoma and 2 with adrenal adenomas) and in 21 patients without Cushing's syndrome. The 24-hour urinary free cortisol levels and mean and integrated 13h00-16h00 plasma cortisol estimations clearly distinguished patients with Cushing's syndrome from those without. However, adequate suppression on dexamethasone suppression tests (false negatives) were obtained in 3 of the 9 patients with Cushing's syndrome. Since the integrated 13h00-16h00 plasma cortisol estimation is cheaper and simpler than the mean 13h00-16h00 plasma cortisol estimation, we recommend it as an adjunct in the diagnosis of Cushing's syndrome.  相似文献   
7.
Huntington chorea is rare in ethnically pure blacks; 8 South African black patients, 6 adults and 2 children, from 4 families are described. The symptoms do not appear to differ materially from Huntington chorea in other races. Increased awareness of the disease in this population group is warranted.  相似文献   
8.
C Bastien  K Campbell 《Sleep》1992,15(3):236-245
The functional significance and topographical variation of the different components of the evoked K-complex were examined. In the first experiment, the intensity of the stimulus (80 and 60 dB SPL) and its rise-and-fall time (2 and 20 milliseconds) were manipulated during nonrapid eye movement sleep. In the second experiment the tonal frequency (500, 1,000 and 2,000 Hz) of the stimulus was manipulated. In the first experiment, nine stimuli were presented every 10 seconds, whereas in the second, 20 consecutive stimuli were presented. The evoked K-complex consisted of two different negative components peaking at approximately 350 and 550 milliseconds, respectively, and followed by a positive component peaking at approximately 900 milliseconds. K-complexes were easier to elicit for high-intensity fast rise-and-fall time stimuli than for low-intensity slow rise-and-fall time stimuli. The probability of occurrence was not affected by the tonal frequency of the stimulus. When a K-complex was evoked, the amplitude and latency of N350, N550 and P900 remained invariant regardless of its intensity, rise-and-fall or its tonal frequency. The N550-P900 portion of the K-complex therefore appears to be an all-or-none phenomenon. On trials in which a K-complex could not be elicited, N350 was still visible although much attenuated. In these trials, its amplitude was further reduced when stimulus intensity was lowered. N350 might need to reach a certain critical threshold before the much larger N550-P900 complex is elicited.  相似文献   
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The acute muscarinic and nicotinic side-effects of organophosphate poisoning are well known. Less commonly encountered are neurological symptoms such as chorea and psychiatric disturbances such as psychoses and depression. Two patients with organophosphate poisoning are described, both exhibiting marked choreiform dyskinesias and one experiencing severe depression and emotional lability. Both responded well to the appropriate treatment. Because of the widespread use of organophosphate insecticides in agriculture, the neurological and psychiatric effects of chronic low-dose exposure to organophosphates in farmers and their employees deserves attention.  相似文献   
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