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991.
L K Pickering 《American journal of public health》1986,76(6):623-624
992.
L C Harlan B F Polk S Cooper T P Blaszkowski J Ignatius-Smith M Stromer H Mull 《American journal of preventive medicine》1986,2(5):256-261
The effects of labeling a person as hypertensive have important implications for hypertension screening. The Hypertension Detection and Follow-up Program (HDFP) provides an opportunity to examine the effects of labeling, treatment, and study assignment on a large group of hypertensives (n = 10,070). Their answers to questions regarding perceived health and general well-being asked at baseline and again one year later were analyzed. There was no significant change in the perceived health status of persons who were unaware of their hypertension at baseline and remained untreated at one year (labeling alone). The effect of labeling plus treatment was associated with a significant decrease in perceived health. The effect of antihypertensive drug therapy on perceived health status was examined in persons who were aware of their hypertension but not on treatment at baseline, and on treatment at one year. The stepped care group (SC) had a significant improvement in their perceived health and a significant decrease in the amount of time spent worrying about their health. The referred care group (RC) had no change. Program assignment effects were studied in individuals aware of their hypertension and on treatment both at baseline and one year later. Both the SC and RC groups had a significant improvement in their perceptions of their health status. The SC group had a significant decrease in time spent worrying about their health, while the RC group showed no change. These reassuring results fail to support the suggestion that labeling persons as hypertensive is necessarily followed by negative psychological consequences.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
Comparison of two in vitro methods of bone lead analysis and the implications for in vivo measurements 总被引:4,自引:0,他引:4
L J Somervaille D R Chettle M C Scott A C Aufderheide J E Wallgren L E Wittmers G R Rapp 《Physics in medicine and biology》1986,31(11):1267-1274
Atomic absorption spectrometry and x-ray fluorescence have been used to determine the lead content of metatarsal and tibia bone samples. For a range of bone lead levels from 6.5 to 83 micrograms g-1 of ashed bone there is no evidence of a systematic difference between the two techniques of more than 1 microgram g-1. There is, however, some evidence that random differences between the two in vitro analyses applied to the same bone sample are larger than can be accounted for by known measurement uncertainties. Variations in bone composition could account for these differences. Because the x-ray fluorescence technique is applied in an identical way to in vivo analysis, it is concluded that the uncertainties in in vivo measurements are small. 相似文献
994.
995.
P J Landrigan M G Cherniack F A Lewis L R Catlett R W Hornung 《Scandinavian journal of work, environment & health》1986,12(1):32-39
An industrial hygiene and medical survey was conducted in an iron foundry to study the occurrence of silicosis. Breathing zone exposures to respirable crystalline silica had been very high in 1977 [1 045 micrograms/m3 (geometric mean) for coremakers and 198 micrograms/m3 for fettlers]; exposures in 1980 and 1982 were substantially lower. A radiographic evaluation of 188 workers revealed silicosis in 18 (9.6%). Eight had category 1 profusion of small rounded pulmonary lesions (by the 1980 classification of the International Labour Office); two had category 2; and eight had category 3. Two had progressive massive fibrosis. Four workers without silicosis in 1977 had developed lesions by 1980. The prevalence increased from 1.5% among workers employed less than 20 years to 53% among longer term workers. No association was found between the prevalence of silicosis and cigarette smoking. Chronic cough was more common in workers with heavy current dust exposure than in those with light exposure, more common in smokers than in nonsmokers, and more common in silicotics than in nonsilicotics. A multiplicative interaction existed between dust exposure and smoking in the etiology of cough. Silicosis continues to exist in American foundries. Cigarette smoking does not contribute to the causation of silicosis, but it aggravates the attendant respiratory symptoms. 相似文献
996.
Physiology and pathophysiology of skeletal muscle contractions 总被引:4,自引:0,他引:4
L. V. CHRISTENSEN 《Journal of oral rehabilitation》1986,13(5):451-461
An overview is presented of the physiology and pathophysiology of dynamic skeletal muscle contractions in the intact living organism. Dynamic muscle activities are divided into concentric contractions with shortening of muscle fibres and the production of positive work, and eccentric contractions with lengthening of muscle fibres and the production of negative work. In positive work, muscle tension overcomes external forces. In negative work, external forces overcome muscle tension. The latter phenomenon, with relatively few active motor units, explains the injuries induced by eccentric contractions. Both the contractile and non-contractile elements are involved in the muscle injuries and, clinically, they are referred to as myofibrositis. 相似文献
997.
L Paris M Giardina R Pacifici S Pichini P Zuccaro G Sideri 《The Italian Journal of Neurological Sciences》1991,12(5):447-451
We compared two groups of patients with idiopathic epilepsy, 41 patients whose seizure frequency was not controlled by adequate therapy and 39 patients in good seizure control, in respect of hematology, kidney and liver function tests, serum IgG, IgA and IgM concentrations and drug concentrations. The only difference that emerged were in the serum immunoglobulins, which were raised in the drug refractory group, significantly (p less than 0.01) so in the case of IgG. Failure of seizure control did not depend on inadequacy of drug dose or of blood concentration. Although the serum Ig changes do not warrant the assumption of an immunological origin for drug resistance, they do suggest a useful research line. 相似文献
998.
In newly diagnosed adult patients with epilepsy followed prospectively on monotherapy, carbamazepine and phenytoin were associated with a fall in plasma uric acid, but sodium valproate and phenobarbitone were associated with a rise in plasma uric acid. The mechanisms and significance of these findings are discussed. 相似文献
999.
Child psychopathology and environmental influences: discrete life events versus ongoing adversity 总被引:1,自引:0,他引:1
P S Jensen J Richters T Ussery L Bloedau H Davis 《Journal of the American Academy of Child and Adolescent Psychiatry》1991,30(2):303-309
Patterns of exposure to distinct types of life stressors were compared between 134 children attending a military child psychiatric clinic and a matched military community control sample. Compared with the community sample, clinic-referred children had experienced significantly higher levels of normative stressful events as well as events confounded with their own adjustment and events related to parental psychosocial functioning. Differences in levels of normative stressful events were no longer significant, however, when controlling for events related to parental functioning. Ratings of stressful events during the past year significantly underestimated the lifetime stress exposure differences between clinic and community control children. Although normative stressful events, parent-related events, and parent symptomatology ratings were significantly related to child behavior problem ratings, normative stressful events did not contribute to predictions of child behavior problems beyond the variance attributable to parent-related events and parent symptomatology. Implications of these findings for life stress and child maladjustment research are discussed. 相似文献
1000.
Current transition assessment practices. 总被引:1,自引:0,他引:1
Although researchers have called for a movement away from prediction-related assessments to those which identify specific skill deficits, the extent to which professionals responsible for vocational assessment have shifted their focus is uncertain. The purpose of this investigation was to assess the frequency with which specified prediction-related and skill deficit-related vocational assessment procedures were administered by a sample of secondary-level teachers and employment training specialists. Additionally, the frequency with which these professionals used assessment data to aid in decision making was determined. The results revealed that teachers and employment training personnel used a variety of assessment procedures to make transition decisions. The implications of these findings are discussed. 相似文献