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1.
Pattern visual evoked potentials were obtained from 46 patients with definite relapsing/remitting multiple sclerosis, using both a conventional 5-channel occipital array and a 3-D recording technique consisting of three bipolar derivations approximating the three dimensions of space. These three orthogonal wave forms were displayed as a 3-D Lissajous trajectory for each subject. Two of the 15 patients with completely normal conventional pattern VEPs had abnormalities of the orientation of the B-C curvilinear segment of the 3-D pattern VEPs. Delays in the first major occipital positive component (P100) were evident using both techniques; the correlation between P100 latency and the latency of the corresponding trajectory apex was r = 0.99 (P less than 0.01). Post-chiasmal MRI abnormalities were associated with 3-D VEP orientation abnormalities. Three-dimensional pattern VEPs are moderately more sensitive than conventional pattern VEPs at detecting dysfunction posterior to the optic chiasm in demyelinating disease and do not require the use of eccentric fixation to do so.  相似文献   
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The Child and Adolescent Trial for Cardiovascular Health (CATCH) is a multisite intervention research study that builds on significant progress made in school health education research in the 1980s. The study has three phases: Phase I deals with study design, intervention, and measurement development, Phase II involves the main trial in 96 schools in four states, and Phase III focuses on analysis. The intervention program targets third-fifth grade students and focuses on multiple cardiovascular health behaviors, including eating habits, physical activity, and cigarette smoking. Classroom curricula, school environmental change, and family involvement programs are developed for each grade level and behavioral focus. This paper describes Phase II of CATCH with a rationale for cardiovascular health promotion with youth. The process of change that appears to be necessary for school-based health promotion and that will be tested in CATCH are presented as a framework to guide these efforts.  相似文献   
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METHODS: Data were obtained from a longitudinal study sample of 754 adoptees and categorized based on review of the available adoption agency, medical, and psychiatric records of the biological parents. Categorical data were analyzed using chi2 or Fisher's exact tests, as appropriate. Logistic regression analyses were used to assess the relative contribution of variables. RESULTS: There was not a statistically significant difference in the frequency or type of self-reported adult disruptive behavior, arrests, jail stays, felony arrests, or frequency of conduct disorder (CD) when inattentiveness, impulsivity, and hyperactivity were analyzed individually. The contributions of attention deficit hyperactivity disorder (ADHD) were independent and no additional increased risk for future illegal behavior was conferred by the combination of the disorders. While the effect of CD on illegal behavior was correlated with substance abuse and dependence, ADHD continued to be a significant contributor after controlling for substance abuse and dependence. CONCLUSIONS: Data indicated that ADHD and CD are related but different disorders conferring risk for adult illegal behavior or arrest. In this sample, inattention was the most common domain impaired among those with ADHD, followed closely by hyperactivity, with impulsivity reported least often among those endorsing symptoms of ADHD.  相似文献   
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White Carneau pigeons were trained to discriminate 1.0 mg/kg buspirone from saline when key pecking was maintained under a fixed-ratio 30 schedule of food presentation. Buspirone (0.3-10.0 mg/kg), the serotonin 1A (5-HT(1A)) agonist 8-OH-DPAT (0.1-1mg/kg), the buspirone analog BMY 7378 (3.0-5.6mg/kg), the mixed 5-HT(1A/1B) agonist RU 24969 (3.0-10.0mg/kg) and the 5-HT(1A) agonist spiroxatrine (0.1-1.0mg/kg) occasioned at least 80% buspirone-appropriate responding in all subjects tested. Administration of the 5-HT(1B) agonist (TFMPP 0.1-10.0mg/kg) or the 5-HT(3) antagonist (MDL 72222 (3.0-17.0mg/kg) resulted in primarily saline-key responding. The dopamine receptor antagonist chlorpromazine (1.0-17.0mg/kg), the specific D-2 receptor antagonist eticlopride (0.03-0.56mg/kg), the noradrenergic alpha-2 antagonist yohimbine (0.1-1.0mg/kg), the alpha-2 agonist clonidine (0.003-0.10mg/kg) and (+/-) and (-) propranolol (3.0-30.0mg/kg) all produced primarily saline-appropriate responding. Coadministration of the beta-adrenergic agonist isoproterenol (1.0-5.6mg/kg) or the 5-HT(1A) partial agonist BMY 7378 (0.01-10.0mg/kg) with 1.0mg/kg buspirone did not block the discriminative stimulus effects of buspirone. However, 3.0-10.0mg/kg BMY 7378, in combination with a lower dose of buspirone (0.3mg/kg) decreased drug-key responding to approximately 50%. Results from the present study suggest that (1) the discriminative stimulus effects of buspirone, 8-OH-DPAT, BMY 7378, RU 24969 and spiroxatrine are mediated through the 5-HT(1A) receptor; (2) buspirone's discriminative stimulus effects do not interact with the noradrenergic or dopaminergic system; and 3) under this procedure BMY 7378 was a partial agonist at 5-HT(1A) receptors.  相似文献   
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Determination of hepatitis C virus genotype by Pyrosequencing   总被引:4,自引:0,他引:4  
A simple sequencing-based assay is described for genotyping of hepatitis C virus (HCV). RT-PCR was employed to amplify a 237-nucleotide-long fragment from the 5' untranslated region (UTR) of the genome using one biotinylated and one normal primer. Subsequent to capture of the PCR products on streptavidin-coated beads, single-stranded DNA separation, and hybridization of sequencing primer, Pyrosequencing was performed. The genotype of 98 samples out of which 77 samples were from American veterans and 21 samples were from Iran was determined. The samples from the American veterans contained six different subtypes, while five subtypes were found in Iranian samples. For rapid population-specific HCV subtyping, a multiplex assay was developed. This study demonstrates the suitability of this technology for low-cost, high throughput and accurate microbial genotyping.  相似文献   
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