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991.
BACKGROUND: The HIV incidence data are relevant in depicting the current dynamics and trend of the epidemic. Using a new laboratory method for HIV-1 incidence, we aimed at estimating a 10-year trend in HIV-1 incidence in Addis Ababa, Ethiopia. METHODS: We determined the temporal trends in HIV incidence based on a total of 7744 serum specimens from pregnant women who attended antenatal clinics in Addis Ababa between 1995 and 2003. HIV incidence was determined by IgG-capture HIV-1 BED incidence enzyme immunoassay following a validation using a well-characterized panel of serial serum specimens from subtype C-infected seroconverters. FINDINGS: Of the 1350 HIV+ specimens tested as part of the annual sentinel survey between 1995 and 2003, a total of 1332 (98.7%) were tested by BED HIV-1 incidence assay. The incidence rate of HIV-1 infection declined significantly from 7.7% (95% CI, 3.9-11.5%) in 1995 to 2.0% (95% CI, 0.7-3.3%) in 2003. Although there was a trend, amongst the age group of 15-29 years, in age-specific decline in incidence, it was not statistically significant. No change in HIV incidence rate was observed for the group aged above 30 years. INTERPRETATION: A corresponding decline in the incidence of HIV infection was observed with the decline in the prevalence of HIV infection between 1995 and 2003 in Addis Ababa City. Whether the declines were because of changes in sexual behaviours or other reasons needs to be explored. The BED HIV-1 incidence assay provides a valuable tool in obtaining information on recent HIV-1 infection.  相似文献   
992.
Mental imagery is increasingly considered to be an important feature in anxiety disorders. The aim of this study was to investigate the prevalence and characteristics of mental images in obsessive compulsive disorder (OCD) and their possible association with earlier adverse events. A consecutive sample of 37 patients with OCD admitted to a specialist unit was interviewed using a semi-structured interview. Thirty (81%) patients with OCD reported mental images. Most images were either memories of earlier adverse events (n=10 or 34%) or were associated with them (n=13 or 45%). Patients with mental images had more obsessive compulsive symptoms, responsibility beliefs and anxiety than those without. Previous research has shown that patients with OCD and comorbid posttraumatic stress disorder might not benefit as much from standard behavioural treatment as those without. Consequently, additional therapeutic interventions such as imaginal reliving and restructuring of meaning or imagery modification of traumatic memories might be helpful in OCD patients with mental images that are linked to earlier adverse events.  相似文献   
993.
PURPOSE: Associations between rolandic epilepsy (RE) with reading disability (RD) and speech sound disorder (SSD) have not been tested in a controlled study. We conducted a case-control study to determine whether (1) RD and SSD odds are higher in RE probands than controls and (2) an RE proband predicts a family member with RD or SSD, hence suggesting a shared genetic etiology for RE, RD, and SSD. METHODS: Unmatched case-control study with 55 stringently defined RE cases, 150 controls in the same age range lacking a primary brain disorder diagnosis, and their siblings and parents. Odds ratios (OR) were calculated by multiple logistic regression, adjusted for sex and age, and for relatives, also adjusted for comorbidity of RD and SSD in the proband. RESULTS: RD was strongly associated with RE after adjustment for sex and age: OR 5.78 (95% CI: 2.86-11.69). An RE proband predicts RD in family members: OR 2.84 (95% CI: 1.38-5.84), but not independently of the RE proband's RD status: OR 1.30 (95% CI: 0.55-12.79). SSD was also comorbid with RE: adjusted OR 2.47 (95%CI: 1.22-4.97). An RE proband predicts SSD in relatives, even after controlling for sex, age and proband SSD comorbidity: OR 4.44 (95% CI: 1.93-10.22). CONCLUSIONS: RE is strongly comorbid with RD and SSD. Both RD and SSD are likely to be genetically influenced and may contribute to the complex genetic etiology of the RE syndrome. Siblings of RE patients are at high risk of RD and SSD and both RE patients and their younger siblings should be screened early.  相似文献   
994.
OBJECTIVE: To compare nonreferred, emergency department (ED)-admitted mild traumatic brain injury (MTBI) patients with and without self-reported cognitive complaints on (1) demographic variables and injury characteristics; (2) neuropsychological test performance; (3) 12-day self-monitoring of perceived cognitive problems; and (4) emotional distress, physical functioning, and personality. METHODS: (Neuro)psychological assessment was carried out 6 months post-injury in 79 patients out of a cohort of 618 consecutive MTBI patients aged 18-60, who attended the ED of our level I trauma centre. Cognitive complaints were assessed with the Rivermead Postconcussional Symptoms Questionnaire (RPSQ). In addition, patients monitored concentration problems and forgetfulness during 12 consecutive days. RESULTS: Self-reported cognitive complaints were reported by 39% of the patients. These complaints were strongly related to lower educational levels, emotional distress, personality, and poorer physical functioning (especially fatigue) but not to injury characteristics. Severity of self-reported cognitive complaints was neither associated with the patients' daily observations of cognitive problems nor with outcome on a range of neuropsychological tests. CONCLUSION: Self-reported cognitive complaints were more strongly related to premorbid traits and physical and emotional state factors than to actual cognitive impairments. In line with previous work, this suggests that treatment of emotional distress and fatigue may also reduce cognitive complaints. Cognitive outcome assessment of symptomatic MTBI patients should not be restricted to checklist ratings only, but also include a (neuro)psychological screening. In addition, daily monitoring of complaints is a useful method to gather information about the frequency and pattern of cognitive problems in daily life.  相似文献   
995.
The present paper documents the development of autism/autistic spectrum disorder in a consecutive series of nine high-risk infants followed prospectively from 6 months of age. Evidence is provided for two broadly defined subgroups: the first subgroup (n = 6) showed a decrease in IQ between 12 and 24 or 36 months (from average/near average to severe cognitive impairment), whereas the second subgroup (n = 3) continued to obtain average or near average IQs. Signs of autism emerged and/or were more striking earlier in the first subgroup. In all nine children, early impairment in social-communicative development coexisted with atypical sensory and/or motor behaviors, as did a temperamental profile marked by irritability/distress and dysregulated state. Discussion focuses on issues raised by the pattern of findings.  相似文献   
996.
The incidence of dementia and risk factors has not been fully investigated in Japan. Following a prevalence study in 1998, we investigated the incidence and associated factors in the same population in 2003 and 2005. Randomly selected 771 residents in Tajiri were targeted. The final participants included 204 (65.2%) healthy older adults (Clinical Dementia Rating, CDR 0) and 335 (73.1%) people with questionable dementia (CDR 0.5). We analyzed the incidence of dementia and dementing diseases, and possible risk factors. The risk factors included demographics, lifestyle-related factors, vascular risk factors, cognitive functions, and MRI findings. Overall, 3.9% of the CDR 0 and 37.0% of the CDR 0.5 participants developed dementia during the 5-year period, whereas 40.2% of the CDR 0.5 participants developed dementia during the 7-year period. Older adults had a higher incidence. Higher CDR Box scores had a higher incidence. Of the dementing diseases, 60.8% of participants developed Alzheimer' disease (AD), followed by vascular dementia (VaD), 17.9%. Logistic regression analyses showed that age, MMSE, cognitive functions such as recent memory, and generalized atrophy were significant predictors of progression to AD. Similarly, predictive factors for progression to VaD were age, MMSE, cognitive functions such as frontal function, and white matter lesions and cerebrovascular diseases. A comprehensive system including CDR, cognitive tests, and MRI, is recommended in community-based health policy planning.  相似文献   
997.
Slowing of motor performance in human aging is a well demonstrated clinical observation. Age-related motor decline has been also confirmed in animal models including rodents and non human primates. We studied the motor performance of 60 normal subjects (age: 20–87). Motor study included the four timed tests (TT) recommended in CAPIT protocol: pronation–supination (PS), finger dexterity (FD), movement between two points (MTP) or tapping, and walking test (WT). Finally we compared normal controls with a group of 30 patients with Parkinson's disease (PD) of similar age. Age inversely correlated with TT performance in normal subjects (for PS, r:0.33, p < 0.01; FD, r:0.44, p < 0.0005; MTP, r:0.51, p < 0.0001; WT, r:0.59, p < 0.0001, Pearson). Our results confirm that motor performance (measured with CAPIT TT) deteriorates linearly with age. Simple tasks, such as CAPIT TT can help to study and quantify age-related motor decline.  相似文献   
998.
Contradictory evidence exists regarding the nature and degree of impaired cognitive flexibility in PD. Dopaminergic medication may be expected to ameliorate such cognitive deficits, yet both medicated and unmedicated patients have been reported to perform more poorly than control subjects on tasks of cognitive flexibility, suggesting that such deficits may also be affected by other disease-related variables. The present study examined whether asymmetric dopamine deficiency (revealed by unilateral symptom onset) is related to the performance of spontaneous and reactive flexibility in PD, and the possible interaction of dopaminergic medication with such asymmetry. Thirty-five PD patients with mild motor symptoms and unilateral onset of PD (left-onset=14; right-onset=21) performed the Alternate Uses (AU) and intradimensional/extradimensional shift (IED) tasks. Interaction between side of onset and medication was observed for the number of errors in the AU task and number of reversal errors in the IED task. Significantly more AU errors were made by medicated patients with left-onset, as compared to all other participants. Conversely, medicated patients with right-onset made the most reversal errors. These results suggest that relatively early in the disease process when dopamine deficit in the less-affected hemisphere is mild, optimal dopaminergic medication (with respect to motor function) may involve over-medication of the less-affected hemisphere. Thus, AU errors may be the consequence of hyperdopaminergic state leading to impaired functioning of the left hemisphere, whereas increased reversal errors in right-onset PD patients receiving dopaminergic medication is related to impaired dopamine function in the right hemisphere.  相似文献   
999.
Intra-individual variability in reaction time increases with age and with neurological disorders, but the neural correlates of this increased variability remain uncertain. We hypothesized that both faster mean reaction time (RT) and less intra-individual RT variability would be associated with larger corpus callosum (CC) size in older adults, and that these associations would be stronger in adults with mild cognitive disorders. A normative sample (n=432) and a sample with mild cognitive disorders (n=57) were compared on CC area, RT mean and RT variability adjusting for age, sex, education, APOE genotype, smoking, alcohol consumption, grip strength, visual acuity, handedness and lung function. Samples did not differ in CC area or intra-cranial volume. In the normative sample, simple RT (SRT) and choice RT (CRT) were negatively associated with CC area but there were minimal associations between CC area and intra-individual RT variability. In the mild cognitive disorders sample, SRT, CRT and intra-individual variability on the SRT task were associated with CC area. Increased RT variability explained up to 12.7 percent of the variance in CC area in the sample with mild cognitive disorders, but less than 1 percent of the variance in CC area in the normative sample. There were no associations with APOE genotype. We conclude that intra-individual variability is associated with CC area in mild cognitive disorders, but not in normal aging. We propose that biological limits on reserve capacity must occur in mild cognitive disorders that result in stronger brain-behavior relationships being observed.  相似文献   
1000.
Theory of mind (ToM) - our ability to predict behaviors of others in terms of their underlying intentions - has been examined through verbal and nonverbal false-belief (FB) tasks. Previous brain imaging studies of ToM in adults have implicated medial prefrontal cortex (mPFC) and temporo-parietal junction (TPJ) for adults' ToM ability. To examine age and modality related differences and similarities in neural correlates of ToM, we tested 16 adults (18-40 years old) and 12 children (8-12 years old) with verbal (story) and nonverbal (cartoon) FB tasks, using functional magnetic resonance imaging (fMRI). Both age groups showed significant activity in the TPJ bilaterally and right inferior parietal lobule (IPL) in a modality-independent manner, indicating that these areas are important for ToM during both adulthood and childhood, regardless of modality. We also found significant age-related differences in the ToM condition-specific activity for the story and cartoon tasks in the left inferior frontal gyrus (IFG) and left TPJ. These results suggest that depending on the modality adults may utilize different brain regions from children in understanding ToM.  相似文献   
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