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991.
Smoking and stroke. 总被引:2,自引:0,他引:2
The purpose of this review is to evaluate literature published since 1978 on the association between smoking and stroke. Two cohort studies found a dose-response relationship between the amount of cigarettes smoked per day and the relative risk of stroke. Also, two of the cohort studies found that when smoking ceased, the risk of stroke lessened (p less than 0.001). Nine case-control studies found a significant association between smoking and stroke for men and women. The biological association between smoking and stroke is plausible and several epidemiologic studies are supportive of this thesis. Additional, well-designed epidemiologic studies with a sufficient sample size to detect reasonably small odds ratios or relative risks (thus providing adequate statistical power) are warranted. 相似文献
992.
In rodents, chronic estrogenization has been shown to induce degeneration of dendrites and myelin figures in the hypothalamic arcuate nucleus adjacent to peroxidase-positive astrocyte processes. Because in this brain region estradiol is metabolized to 2-hydroxyestradiol (catecholestrogen), we hypothesized that the latter may be oxidized by the astrocytic peroxidase activity to cytotoxic ortho-semiquinones as occurs in peripheral tissues. Cysteamine induces nonenzymatic peroxidase activity in cultured astroglia identical to that observed in vivo. Using electron spin resonance, we demonstrate robust peroxidase-catalyzed oxidation of 2-hydroxyestradiol and dopamine by cysteamine-pretreated astrocyte cultures relative to untreated controls. These results implicate the peroxidase-positive astrocytes in the pathogenesis of estradiol-related hypothalamic damage, parkinsonism, and other free-radical-related neurologic disorders. 相似文献
993.
P M Doraiswamy K R Krishnan O B Boyko M M Husain G S Figiel V J Palese P R Escalona S A Shah W M McDonald W J Rockwell 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):351-356
1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls. 相似文献
994.
J R Glowa J D Bacher M Herkenham P W Gold 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):379-391
1. Rhesus monkeys were equipped with a novel intracerebroventricular (i.c.v.) cannula system and trained to respond under operant schedules of food presentation or termination of stimuli associated with the delivery of shock (escape). 2. CRH decreased food-maintained behavior in a dose-related manner over the range of (0.3-10 micrograms/kg) but did not affect escape responding, demonstrating a selective effect on food-maintained responding. 3. This selective effect was related to the tendency for responding to stop after delivery of a food pellet when higher doses of CRH were given, consistent with the notion that a conditioned aversion to food was established in the presence of CRH. 4. This may suggest that in hyperaroused clinical states such as depression and anorexia nervosa, focus is shifted away from appetitive tasks as a result of increased levels of CRH. 相似文献
995.
S. T. F. M. Frequin F. J. M. Gabreë ls A. A. W. M. Gabreë ls-Festen E. M. G. Joosten 《Clinical neurology and neurosurgery》1991,93(4):323-326
A girl of 14 year is presented with a distal spinal muscular atrophy (SMA) with autosomal recessive inheritance. The technical findings are in agreement with the diagnosis. Light microscopical examination of sural nerve biopsy, including teased fiber studies and morphometry, showed no abnormalities. Electron microscopical investigation however demonstrated axonal pathology. The question arises if distal SMA is a distal axonopathy mainly of motor nerves, but to some extent also of sensory nerves. 相似文献
996.
Summary The prevalence of smoking, hypertension and diabetes mellitus was assessed in 221 patients suffering from internal carotid stenosis and compared with the prevalences in two sex- and age-matched control groups composed of subjects having normal Doppler findings and from non-neurological outpatients. Of the subjects with carotid stenosis 27.6% were hypertensive smokers in comparison with 9.5% and 17.2% in the two control groups. The difference of the stenosis cohort from the two control groups was significant (P<0.01 and P=0.016 respectively). There was no statistically significant differences between the occurrence of diabetes and hypertension in non-smokers and patients who smoked. In 394 investigated patients suffering from carotid stenosis or occlusion an obstruction index, based on the Doppler shift frequency, was calculated. This index was lowest in the normotentive non-smokers. It was only insignificantly higher in the hypertensive non-smokers but significantly so in the normotensive smokers. The index was highest in the hypertensive non-smokers. It was concluded that cigarette smoking, especially if associated with hypertension, is a determinant risk factor for carotid stenosis and occlusion. 相似文献
997.
Atheromatous lesions of the proximal vertebral artery and the subclavian artery may lead to ischaemic manifestations, occasionally with severe consequences in the vertebro-basilar territory. These transient ischaemic attacks are most often caused by haemodynamic insufficiency rather than thrombo-embolic complications addressed by anticoagulant and antiaggregant treatments. In this study, 8 cases of vertebro-basilar ischaemia (VBI), secondary to subclavian and proximal vertebral artery lesions, are reported. Surgical techniques, subclavian-to-subclavian artery by-pass (5 cases) and vertebral to common carotid artery transposition (3 cases) are described with their respective results. Through a review of the literature, the various operative modalities are discussed in the different pathological conditions of the proximal extracranial vertebro-basilar disease. It appears that the subclavian to subclavian artery by-pass as well as the vertebral-to-common carotid artery transposition are safe surgical procedures with strikingly low morbidity and mortality rates. The widely achieved relief of the ischaemic episodes, undoubtedly makes this surgery an alternative to medical treatment. 相似文献
998.
999.
Recent epidemiologic studies have found that the behaviors that characterize seasonal affective disorder (SAD) show seasonal variation in 92%-95% of the general population, suggesting that seasonal variation in behavior and mood is a continuous, dimensional variable extending throughout the general population, defined at the upper extreme by SAD. Research into population seasonality will require a dimensional measure of seasonal variation in mood and behavior that produces a broad, finely graded distribution of seasonality scores sensitive to individual differences throughout the entire range of scores. Accordingly, the Inventory of Seasonal Variation (ISV) was developed as such a measure. This study demonstrated that the ISV has high internal structural validity and is highly sensitive to individual differences in seasonality across its entire range of scores in the normal population. This latter characteristic is not shared by other existing measures of seasonality. Initial external validity of the ISV was supported in that the mean of ISV scores of a SAD sample was found to lie at the 97th percentile of the normal population of scores. Analysis of ISV scores revealed that a winter pattern of seasonality was reported by over 95% of subjects, a pattern that was more pronounced in women than men, while a summer type of seasonality was reported by only 0.6% of the general population. 相似文献
1000.
This paper is an attempt to assess the relevance of the inhibitors of fibrinolysis for clot lysis in selected disease states and to discuss the mechanisms leading to acquired abnormal levels of such inhibitors. When compared to 20 control subjects the 30 hypertriglyceridemic patients (14 with type IIb and 16 with type IV) displayed significantly (p less than 0.001) increased plasma plasminogen activator inhibitor (PAI) activity (221 +/- 88% and 290 +/- 104% respectively; mean +/- SD), moderately (p less than 0.01) increased alpha 2 antiplasmin (alpha 2AP) level (112 +/- 11% and 115 +/- 16%) and accordingly an obviously prolonged dilute blood clot lysis time (DBCLT). Neither PAI activity and alpha 2AP level nor DBCLT were significantly different from controls in the 10 patients with hyperlipoproteinemia type IIa. The 18 patients with severe hepatic cirrhosis had low alpha 2AP level (59 +/- 19.7%) and accelerated clot lysis, while mean PAI activity (160 +/- 87%) was slightly (p less than 0.05) increased. In the 17 nephrotic patients alpha 2AP was increased (115 +/- 12%) while PAI activity was similar to controls and DBCLT rather shorter. Two liver secretion enzymes, namely serum cholinesterase and plasma protein C, were found to be decreased in cirrhotic patients, similar to control values in hyperlipoproteinemia type IIa and obviously increased in nephrotic patients as well as in hypertriglyceridemic subjects. The relevance of PAI and alpha 2AP for clot lysis was considered in relation to data in the literature concerning the behaviour of t-PA and factor XIII.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献