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991.
The relations between DISC-IV DSM diagnoses of ADHD and multi-informant CBCL-AP syndrome scores 总被引:3,自引:0,他引:3
BACKGROUND: Previous studies have examined the relation between attention problems (APs) obtained with the Child Behavior Checklist (CBCL) and attention deficit hyperactivity disorder (ADHD) assessed with the Diagnostic and Statistical Manual of Mental Disorders (DSM). We will examine this relation across sex using multi-informant data. METHODS: Parents of 12538 twins, aged 7, 10, and 12 years, and teachers of twins, aged 10 years, completed the questionnaires. The mothers of a sample of 283 boys and 291 girls who scored either low or high on longitudinal maternal CBCL-AP were interviewed. RESULTS: Children with a low AP score obtained a negative ADHD diagnosis in 96% of cases. Children with a high AP score obtained a positive diagnosis in 36% (girls) and 59% (boys) of cases. The association between paternal and maternal AP ratings and ADHD was the same, whereas the association between teacher AP ratings and ADHD was low. CONCLUSIONS: The association between AP and ADHD is higher in boys than girls, possibly because of a bias toward the male manifestation of ADHD. 相似文献
992.
Philippe N. Tobler George I. Christopoulos John P. O'Doherty Raymond J. Dolan Wolfram Schultz 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(17):7185-7190
When making choices under uncertainty, people usually consider both the expected value and risk of each option, and choose the one with the higher utility. Expected value increases the expected utility of an option for all individuals. Risk increases the utility of an option for risk-seeking individuals, but decreases it for risk averse individuals. In 2 separate experiments, one involving imperative (no-choice), the other choice situations, we investigated how predicted risk and expected value aggregate into a common reward signal in the human brain. Blood oxygen level dependent responses in lateral regions of the prefrontal cortex increased monotonically with increasing reward value in the absence of risk in both experiments. Risk enhanced these responses in risk-seeking participants, but reduced them in risk-averse participants. The aggregate value and risk responses in lateral prefrontal cortex contrasted with pure value signals independent of risk in the striatum. These results demonstrate an aggregate risk and value signal in the prefrontal cortex that would be compatible with basic assumptions underlying the mean-variance approach to utility. 相似文献
993.
994.
Risk of cerebral venous thrombosis
and novel gene polymorphisms of the
coagulation and fibrinolytic systems 总被引:3,自引:0,他引:3
Lichy C Dong-Si T Reuner K Genius J Rickmann H Hampe T Dolan T Stoll F Grau A 《Journal of neurology》2006,253(3):316-320
BACKGROUND AND PURPOSE: Genetic thrombophilic conditions such as those associated with Factor V Leiden (FVL) and the prothrombin mutant (PT G20210A) have been identified as risk factors for cerebral venous thrombosis (CVT). Recently, a single nucleotide polymorphism (SNP) of the thrombin activatable fibrinolysis inhibitor (TAFI G-438A) has been shown to be associated with lower TAFI levels and to decrease the risk for peripheral venous thrombosis. Furthermore, a protective role in juvenile stroke was shown for a SNP of the vitamin K dependent protein Z (PZ Intron F G79A) which is linked with low PZ levels. PATIENTS AND METHODS: In 77 consecutive patients with CVT and in 203 randomly selected population controls from the same region of Southern Germany, we investigated the following functional SNPs using PCR and restriction fragment analysis techniques: TAFI G-438A, PZ Intron F G79A, FVL and PT G20210A. RESULTS: The prevalence of FVL tended to be higher (OR 2.08, 95 % CI 0.91-4.75, p = 0.06) and that of PT G20210A (OR 4.57, 95 % CI 1.45-14.44, p = 0.007) was significantly higher in patients with CVT than in controls. The A-allele frequency of the TAFI G-438A polymorphism did not significantly differ between patients (21.3 %) and controls (26.9%; OR 0.71, 95 % CI 0.45-1.12; p = 0.17). For the PZ G79A SNP, the frequency of the A-allele was 19.5% in CVT and 24.6% in controls (OR 0.77, 95 % CI 0.49-1.21; p = 0.31). CONCLUSIONS: In this large series of CVT patients, a positive association with established thrombophilic risk factors FVL and especially the PT G20210A mutation was confirmed. In contrast, our study found no significant association of CVT with SNPs of the TAFI and the PZ genes. Other than testing for FVL and the PT G20210A mutation, exploration of these potential thrombophilic variants seems to be of limited value in the investigation of CVT. 相似文献
995.
Susanne A. Schneider MD PhD Burkhard Pleger MD Bogdan Draganski MD Carla Cordivari MD FRCP John C. Rothwell PhD Kailash P. Bhatia MD Ray J. Dolan MD PhD 《Movement disorders》2010,25(1):76-83
Dystonia is associated with impaired somatosensory ability. The electrophysiological method of repetitive transcranial magnetic stimulation (rTMS) can be used for noninvasive stimulation of the human cortex and can alter cortical excitability and associated behavior. Among others, rTMS can alter/improve somatosensory discrimation abilities, as shown in healthy controls. We applied 5Hz‐rTMS over the left primary somatosensory cortex (S1) in 5 patients with right‐sided writer's dystonia and 5 controls. We studied rTMS effects on tactile discrimination accuracy and concomitant rTMS‐induced changes in hemodynamic activity measured by functional magnetic resonance imaging (fMRI). Before rTMS, patients performed worse on the discrimination task than controls even though fMRI showed greater task‐related activation bilaterally in the basal ganglia (BG). In controls, rTMS led to improved discrimination; fMRI revealed this was associated with increased activity of the stimulated S1, bilateral premotor cortex and BG. In dystonia patients, rTMS had no effect on discrimination; fMRI showed similar cortical effects to controls except for no effects in BG. Improved discrimination after rTMS in controls is linked to enhanced activation of S1 and BG. Failure of rTMS to increase BG activation in dystonia may be associated with the lack of effect on sensory discrimination in this group and may reflect impaired processing in BG‐S1 connections. Alternatively, the increased BG activation seen in the baseline state without rTMS may reflect a compensatory strategy that saturates a BG contribution to this task. © 2010 Movement Disorder Society 相似文献
996.
The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) protects from toxicity and mutations incurred following alkylating agents by removing O(6)-alkylguanine lesions. Using Mgmt-/- mice, we examined MGMT's role in protecting from in vivo mutations induced by three different alkylating agents, temozolomide (TMZ), 1,3-bis (2-chloroethyl)-1-nitrosourea (BCNU) and cyclophosphamide. Mutant frequencies were determined in the hypoxanthine-guanine phosphoribosyltransferase gene of splenic T-lymphocytes from C57BL/6 mice (Mgmt+/+ and Mgmt-/-) following TMZ, BCNU or cyclophosphamide. Following TMZ, the mutation frequency was significantly greater in Mgmt-/- mice (5.5 and 9.8 x 10(-6) for 7 and 10 mg/kg TMZ, respectively) compared with vehicle-treated mice (1.0 x 10(-6), P 相似文献
997.
998.
Dolan K Kite B Black E Aceijas C Stimson GV;Reference Group on HIV/AIDS Prevention Care among Injecting Drug Users in Developing Transitional Countries 《The Lancet infectious diseases》2007,7(1):32-41
High prevalence of HIV infection and the over-representation of injecting drug users (IDUs) in prisons combined with HIV risk behaviour create a crucial public-health issue for correctional institutions and, at a broader level, the communities in which they are situated. However, data relevant to this problem are limited and difficult to access. We reviewed imprisonment, HIV prevalence, and the proportion of prisoners who are IDUs in 152 low-income and middle-income countries. Information on imprisonment was obtained for 142 countries. Imprisonment rates ranged from 23 per 100,000 population in Burkina Faso to 532 per 100,000 in Belarus and Russia. Information on HIV prevalence in prisons was found for 75 countries. Prevalence was greater than 10% in prisons in 20 countries. Eight countries reported prevalence of IDUs in prison of greater than 10%. HIV prevalence among IDU prisoners was reported in eight countries and was greater than 10% in seven of those. Evidence of HIV transmission in prison was found for seven low-income and middle-income countries. HIV is a serious problem for many countries, especially where injection drug use occurs. Because of the paucity of data available, the contribution of HIV within prison settings is difficult to determine in many low-income and middle-income countries. Systematic collection of data to inform HIV prevention strategies in prison is urgently needed. The introduction and evaluation of HIV prevention strategies in prisons are warranted. 相似文献
999.
Frances K Wiseman Olivia Sheppard Jacqueline M Linehan Sebastian Brandner Victor LJ Tybulewicz Elizabeth MC Fisher 《Journal of negative results in biomedicine》2010,9(1):7
Background
Down syndrome (DS) is caused by trisomy of all or part of chromosome 21. To further understanding of DS we are working with a mouse model, the Tc1 mouse, which carries most of human chromosome 21 in addition to the normal mouse chromosome complement. This mouse is a model for human DS and recapitulates many of the features of the human syndrome such as specific heart defects, and cerebellar neuronal loss. The Tc1 mouse is mosaic for the human chromosome such that not all cells in the model carry it. Thus to help our investigations we aimed to develop a method to identify cells that carry human chromosome 21 in the Tc1 mouse. To this end, we have generated a panel of antibodies raised against proteins encoded by genes on human chromosome 21 that are known to be expressed in the adult brain of Tc1 mice 相似文献1000.
Effectiveness of highly-active antiretroviral therapy by race/ethnicity 总被引:14,自引:0,他引:14
Silverberg MJ Wegner SA Milazzo MJ McKaig RG Williams CF Agan BK Armstrong AW Gange SJ Hawkes C O'Connell RJ Ahuja SK Dolan MJ;Tri-Service AIDS Clinical Consortium Natural History Study Group 《AIDS (London, England)》2006,20(11):1531-1538
OBJECTIVE: To determine the effectiveness of HAART by race/ethnicity. DESIGN: Prospective multicenter cohort study. METHODS: We studied 991 African-Americans and 911 European-Americans enrolled in the United States Military's Tri-Service AIDS Clinical Consortium Natural History Study who had dates of HIV seroconversion known within 5 years and followed between 1990 and 2002. We determined the rate of disease progression to AIDS and death for subjects in this cohort. Multivariable models evaluated race, pre-HAART (1990-1995) and HAART (1996-2002) eras, age, gender and military service. RESULTS: In the pre-HAART era, African-Americans had a statistically nonsignificant trend towards better outcomes: the relative hazards (RH) of AIDS and death for African-Americans compared to European-Americans were 0.85 [95% confidence interval (CI), 0.68-1.05] and 0.77 (95% CI, 0.55-1.08), respectively. In the HAART era, outcomes were similar by race: 1.17 (95% CI, 0.86-1.61) for AIDS and 1.11 (95% CI, 0.81-1.53) for death with overlapping Kaplan-Meier curves. Relative to the pre-HAART era, the adjusted RH of AIDS in the HAART era was 0.41 (95% CI, 0.31-0.54) and 0.30 (95% CI, 0.22-0.40) for African-American and European-American participants, respectively. Analogous RH for death were 0.55 (95% CI, 0.38-0.80) and 0.38 (95% CI, 0.27-0.54). The precipitous declines in AIDS and death in the HAART era were not statistically different by race. CONCLUSIONS:: In a large multi-racial cohort with equal access to health care, HIV treatment outcomes by race/ethnicity were similar. 相似文献