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991.
Slices of mouse cerebellum preloaded with [3H]serotonin were superfused with a solution of Krebs-Ringer phosphate. The effects of exogenous serotonin, serotonin antagonists, fluoxetine, Ca2+ absence, Ca2+ chelation and frequency of stimulation on basal and electrically induced tritium overflow were investigated. Exogenous unlabeled serotonin decreased the stimulus-evoked tritium overflow in a concentration-related manner. This effect was blocked by simultaneous administration of methiothepin, but not by methysergide. When given alone, methiothepin did not alter the electrically induced tritium overflow at 50 Hz, but did potentiate the increased tritium overflow produced at 100 Hz. The basal tritium efflux was increased by exogenous serotonin, but this effect was reversed by the simultaneous administration of fluoxetine. Under this condition exogenous serotonin reduced the basal tritium efflux in a concentration-related manner. Superfusion of the slices with a Ca2+-free solution alone or in the presence of EGTA, reduced the basal tritium efflux and the stimulated tritium overflow. These results support the existence of serotoninergic presynaptic inhibitory autoreceptors in the cerebellum of the mouse.  相似文献   
992.
993.
Techniques of body radioactivity measurement were used to study the clearance of activated tantalum oxide accidentally inhaled by three reactor workers. The whole-body retention after 7 days was about 1% of the initial deposit. In one subject studied for a further 424 days the residual activity in the thorax was cleared with a biological half-life of about 1,400 days. The results support indications from other studies that tantalum powder administered in aerosol bronchography may be subject to prolonged alveolar retention.  相似文献   
994.
995.
The records of 74 patients diagnosed as suffering from tuberculous (TB) bone or joint disease between 1969 and 1979 were analysed retrospectively. Most were resident in the Greater Manchester County. Thirty-eight patients were first-generation immigrants, and teenage males were particularly prominent in this group. In the indigenous patients the diagnosis was often delayed several months or years, and in a number of subjects there was a history of previous bone and joint tuberculosis. There was a wide range of affected sites, especially in the immigrant group, and evidence of nonarticular TB was found in only a minority of patients. Diagnosis is most satisfactorily based on open biopsy and submission of pathological material to culture and histology. British subjects were more likely to have to undergo remedial surgery for the disease, especially when weight bearing joints were involved. Antituberculous chemotherapy should be given for at least 1 year to prevent recurrence of the disease.  相似文献   
996.
Familial neurocardiogenic (vasovagal) syncope   总被引:4,自引:0,他引:4  
Vasovagal syncope (VSS) is an exaggerated tendency towards the common faint caused by a sudden and profound hypotension with or without bradycardia. The etiology of VVS is unknown though several lines of evidence indicate central and peripheral abnormalities of sympathetic function. Studies however indicate a strong heritable component to the etiology of VVS in over 20% of cases. Here, we report the findings from a family that shows apparently autosomal dominant VVS in at least three generations. Clinical findings included an absence of any discernible cardiac or autonomic abnormalities and reproducible hypotension on tilt table testing in affected family members.  相似文献   
997.
The cost for the Roche Monitor assay kit can be reduced 50% by using only the 1:1, 1:25, and 1:625 human immunodeficiency virus (HIV) and the 1:1 quantitation standard dilutions. This abbreviated test applied to 1,774 mostly African samples had results nearly identical to those obtained following the package insert instructions. To make this approach feasible, Roche would have to provide additional lysis buffer and master mix.  相似文献   
998.
Ruehlman LS  Karoly P  Newton C  Aiken LS 《Pain》2005,113(1-2):82-90
From a biopsychosocial perspective, assessing chronic pain's psychological impact should involve at minimum the measurement of pain severity, functional interference, and pain-related emotional burden. This article details the development of a brief instrument, the 15-item Profile of Chronic Pain: Screen (PCP:S), designed to address these three key elements in a national (US) sample of over 2400 individuals recruited via random digit dialing. Retest reliability, internal consistency, and preliminary validity were excellent. The scales also demonstrated minimal social desirability response bias. A series of confirmatory factor analyses on several distinct samples revealed a stable, 3-factor solution reflecting pain severity, interference, and emotional burden. Finally, national norms were developed by gender and three age groups. In view of its strong psychometric properties, the PCP:S has the potential to serve as a brief, cost-effective assessment tool for identifying individuals whose chronic pain merits more detailed psychosocial evaluation.  相似文献   
999.
Jacoby A  Rannard A  Buck D  Bhala N  Newton JL  James OF  Jones DE 《Gut》2005,54(11):1622-1629
BACKGROUND AND AIMS: Study of health related quality of life (HRQOL) and the factors responsible for its impairment in primary biliary cirrhosis (PBC) has, to date, been limited. There is increasing need for a HRQOL questionnaire which is specific to PBC. The aim of this study was to develop, validate, and evaluate a patient based PBC specific HRQOL measure.Subjects and METHODS: A pool of potential questions was derived from thematic analysis of indepth interviews carried out with 30 PBC patients selected to represent demographically the PBC patient population as a whole. This pool was systematically reduced, pretested, and cross validated with other HRQOL measures in national surveys involving a total of 900 PBC patients, to produce a quality of life profile measure, the PBC-40, consisting of 40 questions distributed across six domains. The PBC-40 was then evaluated in a blinded comparison with other HRQOL measures in a further cohort of 40 PBC patients. RESULTS: The six domains of PBC-40 relate to fatigue, emotional, social, and cognitive function, general symptoms, and itch. The highest mean domain score was seen for fatigue and the lowest for itch. The measure has been fully validated for use in PBC and shown to be scientifically sound. PBC patient satisfaction, measured in terms of the extent to which a questionnaire addresses the problems that they experience, was significantly higher for the PBC-40 than for other HRQOL measures. CONCLUSION: The PBC-40 is a short easy to complete measure which is acceptable to PBC patients and has significantly greater relevance to their problems than other frequently used HRQOL measures. Its scientific soundness, shown in extensive testing, makes it a valuable instrument for future use in clinical and research settings.  相似文献   
1000.
BACKGROUND: Dizziness is a common symptom in older people that affects quality of life and increases the risk of falls. Benign paroxysmal positional vertigo (BPPV) is a common cause of dizziness that increases in prevalence with age, and is potentially curable. AIM: To compare patients with BPPV referred initially to a Falls and Syncope Unit (FSS group) with those initially referred to a Regional ENT/Balance Service (ENT group). DESIGN: Retrospective case-note review. METHODS: Medical notes, investigations and outcomes were reviewed for all patients. RESULTS: Of 59 patients with BPPV confirmed by Dix-Hallpike test, 31 (53%) were initially referred to the FSS (2.6 patients per month, 71% females) and 28 (47%) were initially referred to ENT (4.7 patients per month, 86% females). Compared to those referred initially to ENT, FSS patients were significantly older (mean +/- SD 69 +/- 13 vs. 55.4 +/- 13 years, p = 0.0003) and had dizzy symptoms for longer before diagnosis (median (range) 12 (4-120) vs. 6 (1-36) months, p = 0.0273). FSS patients were more likely to have more than one type of dizziness (16% vs. 0%, p = 0.001), more likely to have cerebrovascular or cardiovascular co-morbidity (13% vs. 4%, p = 0.0152) and were taking significantly more medications (3.2 vs. 1.7; p = 0.0271). Cure rates on intervention were similar (83% FSS, 86% ENT). DISCUSSION: BPPV is a potentially curable cause for dizziness in older people. Older people are frequently referred directly to Falls units, who will be seeing increasing numbers of patients with dizziness. A high index of suspicion allows early identification and treatment of this condition.  相似文献   
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