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Some auditory event-related potential (ERP) abnormalities characterize both patients with schizophrenia and subjects with schizotypal personality disorder. It was therefore hypothesized that subjects from the community with schizotypal traits might also present ERP abnormalities. In this study, we compared auditory ERP latencies and amplitudes in 13 subjects with high (H-SPQ) and 12 subjects with low (L-SPQ) scores on the Schizotypal Personality Questionnaire (SPQ), selected from 198 Tunisian students. Auditory ERPs were recorded at Fz, Cz, and Pz, with a standard oddball paradigm. Smaller P300 amplitudes and delayed P300 latencies were found in H-SPQ compared with L-SPQ participants. Confirming previous reports, our results suggest that reduced P300 amplitudes and delayed P300 latencies may be considered as vulnerability markers of the schizophrenia spectrum in nonclinical subjects from the community.  相似文献   
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To ascertain the regional cerebral blood flow (CBF) responses to hypoglycemia, nine newborn dogs were treated with insulin to blood glucose concentrations ranging from 1 to 35 mg/dl (mean 22 mg/dl). Systemic physiologic monitoring revealed no differences in mean arterial blood pressure, heart rate, paO2, paCO2, pHa, or blood lactate in the hypoglycemis animals and five normoglycemic controls. Significant increases in CBF occurred in 17 of 20 analyzed structures of brain in the hypoglycemic puppies, ranging from 158 to 446% of the normoglyycemic values. The percent increases in CBF were greatest in brainstem structures compared to other major regions of brain. A positive correlation existed between mean arterial blood pressure and cerebral cortical blood flow, suggesting a loss of CBF autoregulation during hypoglycemia. The pathophysiologic mechanism for the elevations in regional CBF might relate to stimulation of beta-adrenergic receptors in brain, as has been shown in adults.  相似文献   
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Many different suture techniques are routinely used by cutaneous surgeons for the closure of surgical wounds. This paper reviews several common suture techniques and their associated subtypes. In particular, for each technique, we discuss the method for placement, generally accepted indications, controversies regarding utility, and objective evidence of efficacy.  相似文献   
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Vehicle services create the potential for heavy metal accumulation in the working environment. This study assessed five vehicle services, namely body repair, oil exchange, mechanical repair, tire repair, electrical repair, and washing services for three types of vehicles: airplanes, buses, and cars. The results show that there are significant increases in the total contents of Fe, Cu, Pb, Zn, Ni, Mn, and Cr in ambient dust, with Fe being the highest and Cr the lowest. The main cause of the presence of these elements is due to the metals' corrosion from vehicle sources and petroleum residue. Variations in the concentrations with the type of service and within the same service at different locations were observed. In this study, the exposure of prepubertal male mice to industrial metal salts in drinking water at a concentration of 1000 ppm for 90 days was investigated. Exposure of male mice to lead acetate significantly reduced the social aggression of the resident untreated subjects. Additionally, this treatment resulted in decreasing weights of body, testes, preputial glands, and seminal vesicles. In comparison, no such effects were seen in mice given copper chloride or manganese chloride. The results show that only lead acetate produced a pattern of responses clearly indicative of altered gonadal function.  相似文献   
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Iron status: a possible risk factor for the first febrile seizure   总被引:2,自引:0,他引:2  
PURPOSE: We conducted a controlled study to investigate the relation of iron status and first febrile seizure (FFS). METHODS: Measures of iron sufficiency including hemoglobin concentration (HB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and plasma ferritin (PF) were prospectively measured in 75 children with FFS and compared with 75 controls matched for age and sex with febrile illnesses without convulsions. RESULTS: Mean ferritin level was significantly lower in cases with FFS (29.5 +/- 21.3 microg/L) than in controls (53.3 +/- 37.6 microg/L) with p = 0.0001. The proportion of subjects with a PF level 相似文献   
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