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941.
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
942.
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
943.
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
944.
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
945.
946.
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
947.
Olgierd Pucilowski W. Danysz D.H. Overstreet A.H. Rezvani B. Eichelman D.S. Janowsky 《Brain research bulletin》1991,26(4):621-625
The Flinders Sensitive Line (FSL) of rats has been selectively bred to have increased sensitivity to cholinergic agonists. However, these rats exhibit altered responsiveness to a number of noncholinergic agents, such as apomorphine, buspirone and ethanol. This study compared the FSL and control Flinders Resistant Line (FRL) rats in terms of their hyperthermic response to the phencyclidine (PCP) receptor agonist, MK-801 (0.2 mg/kg SC) and their MK-801 binding characteristics. We have found that FSL rats react with a delayed hyperthermia, having a significantly lower hyperthermia for the first 120 min of observation. Thereafter the response does not differ in FSL and FRL rats. Both groups had similar affinities and numbers of [3H]MK-801 binding sites in the hippocampus/cerebral cortex. Pretreatment with scopolamine (1 mg/kg SC) failed to affect MK-801-induced hyperthermia in either line of rats. These findings suggest that selective breeding of FSL rats attenuated the secondary mechanisms involved in the PCP receptor-mediated hyperthermic response. However, by itself cholinergic supersensitivity does not appear to be a major factor in the blunted responsiveness of FSL rats to MK-801. 相似文献
948.
949.
950.
J M Esteban J A Kuhn B Felder J Y Wong H Battifora J D Beatty P M Wanek J E Shively 《Cancer research》1991,51(14):3802-3806
We have previously shown that the colon carcinoma (LS174T) xenografts that emerged shortly after radioimmunotherapy with 90Y-labeled anti-CEA monoclonal antibody (MAb) ZCE025 lacked significant expression of CEA in comparison with the untreated tumors. The present study was designed to establish if the immunophenotype of the treated tumors was the result of CEA specific therapy and if the effect was permanent. Athymic mice bearing LS174T tumors were treated either with 120 mu Ci of 90Y-ZCE025, an equal dose of 90Y-96.5 (nonspecific MAb), or received no treatment. When the treated tumors grew to approximately 1.5 cm in diameter (6 weeks after therapy), they were resected and aliquoted to be transplanted to other mice, plated in tissue culture, fixed in formalin, and homogenized for CEA quantitation. The procedure was repeated 3 times (a total of 4 months after treatment). The CEA content was evaluated 2 and 6 weeks after therapy and when the tumors were transplanted. We confirmed a 4-fold decrease of CEA in the resurgent tumors 6 weeks after specific 90Y-ZCE025 therapy, which was twice the decrease experienced by the tumors treated with nonspecific 90Y-96.5, indicating substantial and specific killing of CEA-expressing cells. The CEA content slowly but progressively increased with each new pass of the tumor in the mice, reaching approximately one-half the value of the controls at the end of the study. The resurgent tumors were also studied by immunohistochemistry with MAbs detecting different epitopes of CEA, keratin, TAG-72, and epithelial membrane antigen to evaluate possible additional immunophenotypic changes induced by radioimmunotherapy. Only the expression of TAG-72 (recognized by MAb B72.3) increased immediately after therapy, but it returned to the original levels by the end of the study. These results suggest that: (a) specific radioimmunotherapy with 90Y-ZCE025 selectively kills cells that express higher levels of CEA; (b) the immunophenotype of the surviving fraction of the tumor appears to slowly revert to its original form; and (c) other tumor markers unrelated to CEA can also be affected. These observations have important implications for the design of radioimmunotherapy trials. 相似文献