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This study evaluates the event-related potential (ERP) components in a single outcome gambling task that involved monetary losses and gains. The participants were 50 healthy young volunteers (25 males and 25 females). The gambling task involved valence (loss and gain) and amount (50 cent and 10 cent) as outcomes. The outcome-related negativity (ORN/N2) and outcome-related positivity (ORP/P3) were analyzed and compared across conditions and gender. Monetary gain (compared to loss) and higher amount (50 cent compared to 10 cent) produced higher amplitudes and shorter latencies in both ORN and ORP components. Difference wave plots showed that earlier processing (200-400 ms) is dominated by the valence (loss/gain) while later processing (after 400 ms) is marked by the amount (50 cent/10 cent). Functional mapping using Low Resolution Electromagnetic Tomography (LORETA) indicated that the ORN separated the loss against gain in both genders, while the ORP activity distinguished the 50 cent against 10 cent in males. This study further strengthens the view that separate brain processes/circuitry may mediate loss and gain. Although there were no gender differences in behavioral and impulsivity scores, ORN and ORP measures for different task conditions had significant correlations with behavioral scores. This gambling paradigm may potentially offer valuable indicators to study outcome processing and impulsivity in normals as well as in clinical populations.  相似文献   
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AIMS: To raise awareness among the professional clinical and research community of the risk of cocaine misuse among elderly patients. METHODS: Case report of a male patient, aged 72 years, who presented to a community substance misuse service with cocaine use disorder (hydrochloride and base form). RESULTS: The development of the disorder was marked by high levels of cocaine (and later crack cocaine use), repeated periods of abstinence followed by relapse in the past 4 years, with severe consequences to the patient and his family. Treatment involved a close collaboration between several specialist addictions and old-age psychiatry teams in National Health Service. IMPLICATIONS: Although dependence on cocaine among the elderly is considered very rare, clinical management can be challenging and is likely to require the involvement of several specialist and general health services.  相似文献   
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The Family Investigation of Nephropathy and Diabetes (FIND) was initiated to map genes underlying susceptibility to diabetic nephropathy. A total of 11 centers participated under a single collection protocol to recruit large numbers of diabetic sibling pairs concordant and discordant for diabetic nephropathy. We report the findings from the first-phase genetic analyses in 1,227 participants from 378 pedigrees of European-American, African-American, Mexican-American, and American Indian descent recruited from eight centers. Model-free linkage analyses, using a dichotomous definition for diabetic nephropathy in 397 sibling pairs, as well as the quantitative trait urinary albumin-to-creatinine ratio (ACR), were performed using the Haseman-Elston linkage test on 404 microsatellite markers. The strongest evidence of linkage to the diabetic nephropathy trait was on chromosomes 7q21.3, 10p15.3, 14q23.1, and 18q22.3. In ACR (883 diabetic sibling pairs), the strongest linkage signals were on chromosomes 2q14.1, 7q21.1, and 15q26.3. These results confirm regions of linkage to diabetic nephropathy on chromosomes 7q, 10p, and 18q from prior reports, making it important that genes underlying these peaks be evaluated for their contribution to nephropathy susceptibility. Large family collections consisting of multiple members with diabetes and advanced nephropathy are likely to accelerate the identification of genes causing diabetic nephropathy, a life-threatening complication of diabetes.  相似文献   
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Regulation of endosomal trafficking by Rab GTPases depends on selective interactions with multivalent effectors, including EEA1 and Rabenosyn-5, which facilitate endosome tethering, sorting, and fusion. Both EEA1 and Rabenosyn-5 contain a distinctive N-terminal C2H2 zinc finger that binds Rab5. How these C2H2 zinc fingers recognize Rab GTPases remains unknown. Here, we report the crystal structure of Rab5A in complex with the EEA1 C2H2 zinc finger. The binding interface involves all elements of the zinc finger as well as a short N-terminal extension but is restricted to the switch and interswitch regions of Rab5. High selectivity for Rab5 and, to a lesser extent Rab22, is observed in quantitative profiles of binding to Rab family GTPases. Although critical determinants are identified in both switch regions, Rab4-to-Rab5 conversion-of-specificity mutants reveal an essential requirement for additional substitutions in the proximal protein core that are predicted to indirectly influence recognition through affects on the structure and conformational stability of the switch regions.  相似文献   
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Inflammopharmacology - The severity and perseverance of inflammation have been demonstrated in many health conditions. The limitations of existing medications suggest the need for new alternative...  相似文献   
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PURPOSE: Little is known about the prognostic significance of persistent auras following temporal lobe surgery in determining the recurrence of complex partial seizures (CPS) or generalized tonic-clonic seizures (GTCS). METHODS: In a retrospective analysis of temporal lobectomy patients who had preoperative auras associated with CPS or GTCS and who were seizure-free following surgery, the predictive value of auras was assessed at 3 months and 2 years following surgery. Medication use, in relation to the presence of auras, was also assessed. RESULTS: Three hundred and forty-seven patients were seizure-free for 3 months following surgery (247 aura-free, 101 with persistent auras). KM analysis yielded no difference in outcome (p=0.65) and current outcome class was also similar (p=0.99). Patients with persistent auras were somewhat more likely to be on medication at the time of recurrence (p=0.06) and at last follow-up (p=0.09). 224 patients were seizure-free for 2 years following surgery (163 aura-free, 61 with persistent auras). KM analysis yielded no difference in outcome (p=0.86) and current outcome class was also similar (p=0.35). Patients with persistent auras were more likely to be on medication at the time of recurrence (p<0.001) and at last contact (p<0.01). CONCLUSIONS: Auras were not associated with increased risk of recurrence, although increased rates of AED use were seen in these patients. However, any medication effect appears to be quite small, so we consider it reasonable to advise cessation of AEDs in patients with persistent auras who are otherwise seizure-free.  相似文献   
69.
Excision of Mullerian structures in children with disorders of sexual differentiation is an operative challenge. We report our experience with laparoscopic excision of Mullerian structures in a neonate with mixed gonadal dysgenesis. The salient features of the procedure were excellent visualisation and ease of dissection.  相似文献   
70.
Mortality rates in geriatric patients with spinal cord injuries   总被引:1,自引:0,他引:1  
OBJECT: The authors undertook this study to evaluate the incidence of spinal cord injury (SCI) in geriatric patients (> or = 70 years of age) and examine the impact of patient age, extent of neurological injury, and spinal level of injury on the mortality rate associated with traumatic SCI. METHODS: A prospectively maintained SCI database (3481 patients) at a single institution was retrospectively studied for the period from 1978 through 2005. Parameters analyzed included patient age, admission American Spinal Injury Association (ASIA) motor score, level of SCI, mechanism of injury, and mortality data. The data pertaining to the 412 patients 70 years of age and older were compared with those pertaining to the younger cohort using a chi-square analysis. RESULTS: Since 1980, the number of SCI-related hospital admissions per year have increased fivefold in geriatric patients and the percentage of geriatric patients within the SCI population has increased from 4.2 to 15.4%. In comparison with younger patients, geriatric patients were found to be less likely to have severe neurological deficits (greater percentage of ASIA Grades C and D injuries), but the mortality rates were higher in the older age group both for the period of hospitalization (27.7% compared with 3.2%, p < 0.001) and during 1-year follow-up. The mortality rates in this older population directly correlate with the severity of neurological injury (1-year mortality rate, ASIA Grade A 66%, Grade D 23%, p < 0.001). The mortality rate in elderly patients with SCI has not changed significantly over the last two decades, and the 1-year mortality rate was greater than 40% in all periods analyzed. CONCLUSIONS: Spinal cord injuries in older patients are becoming more prevalent. The mortality rate in this patient group is much greater than in younger patients and should be taken into account when aggressive interventions are considered and in counseling families regarding prognosis.  相似文献   
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