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141.
142.
A study in which two groups of women were compared prospectively has been carried out. One group (n = 31) complained of premenstrual syndrome (PMS) whereas the other group (n = 12) denied suffering from PMS. It was found that premenstrual symptoms increased significantly in women who complained of PMS although some symptoms (irritability, abdominal swelling) increased significantly in the other group as well. The group that complained of PMS showed significantly greater premenstrual increases in some symptoms than did the comparison group, but not in anxiety, irritability, tension or breast tenderness. In the late follicular phase statistically significant baseline differences occurred between the two groups in depression, anxiety, tension and irritability. Significant correlations between baseline and premenstrual scores in the PMS group were found for most of the symptoms that were studied, particularly for tension, anxiety, sleeplessness and depression. These results suggest that women who complain of premenstrual syndrome may require therapy for their generally higher levels of anxiety and depression throughout the entire menstrual cycle rather than for the premenstrual exacerbation alone.  相似文献   
143.
Metastasizing meningioma   总被引:1,自引:0,他引:1  
T Russell  T Moss 《Neurosurgery》1986,19(6):1028-1030
A very unusual case of metastatic spread of a meningioma is described. The clinical presentation was of extradural spinal cord compression, without evidence of a primary tumor. Computed tomography did not reveal any intracranial meningioma; the histopathology of the extradural spinal tumor was identical with that of two intracranial meningiomas previously excised.  相似文献   
144.
The increased locomotor activity induced by systemic injections of d-amphetamine or scopolamine in rats was studied in Digiscan Animal Activity Monitors. This multifactorial analysis of locomotion demonstrated that activity measures of horizontal (ambulatory), vertical (rearing), stereotypic, and rotational behaviors differed depending on dose and drug. The topographies of these activity variables may be unique for the dopaminergic and cholinergic systems underlying hyperactivity. These results are a first step toward a needed increase in the sophistication of behavioral pharmacological techniques, allowing for the development of specific activity prints for different classes of psychoactive agents.  相似文献   
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Risk factors for the uptake of cigarette smoking were examined prospectively in 2159 non-smoking secondary schoolchildren aged 11-13 who participated in a survey in 1983 and were followed up 30 months later, by which time 35 per cent had taken up smoking. In a multivariate logistic model, the strongest predictors to emerge were prior experimentation with cigarettes and sex, with more girls (41%) than boys (30%) starting to smoke. Other predictors of taking up smoking were being uncertain about smoking in the future, reporting having been drunk, having a boy or girl friend, believing teachers and friends would not mind if they took up smoking, and giving lower estimates of prevalence of smoking among teachers. Parental smoking behaviour and attitudes, beliefs about the effects of smoking on health, opinions about smoking and perceived strictness of parents did not predict take up of smoking when other variables were controlled for. The odds of taking up smoking varied from 0.24 (risk = 0.19) for a child with the most favourable combination of risk factors to 3.49 (risk = 0.78) for a child with the worst prognosis. These results differ from those of many cross sectional studies and hence indicate the importance of a prospective approach to this type of research.  相似文献   
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Problems that can occur when single implants are utilized to restore first molar teeth include the frequent loosening of screws, as well as screws and/or implant breakage. These may result from torquing and rotational movements of the prosthesis during masticatory and parafunctional mandibular movements. When sufficient bone and mesio-distal restorative space is present, the placement of two implants should be considered.  相似文献   
150.
Statement of problem. Controversy surrounds the use of hydrofluoric acid to prepare precementation surfaces of indirect composites.Purpose. This study was conducted to compare effects of combining hydrofluoric or orthophosphoric acid with microetching as precementation treatments.Material and methods. Nine specimens of three composite materials were prepared to simulate heat-cured indirect restorations. The specimen surfaces were prepared with one of three treatments. Adhesive Bond II and Twinlook cements were used to bond a phosphoric acid-etched disk of P50 to the treated surface. Analysis of variance and Scheffé tests were used to assess the bond strength data. Scanning electron microscopy and microscopic analysis of the fractured and treated surfaces were also performed.Results. Bond strengths for all surface treatments did not significantly differ. Hybrids had a higher bond strength with etching than microfills, and mechanical roughening produced the greatest bond strengths with microfills. Microetching with orthophosphoric acid produced higher bond strengths than microetching with hydrofluoric acid on hybrids.Conclusions. Acid etching alone is not sufficient to produce effective bond strengths, and hydrofluoric acid treatments are detrimental to the resin composite. (J Prosthet Dent 1997;77:568-72.)  相似文献   
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