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991.
992.
A simplified diagnostic approach to dizziness in children   总被引:4,自引:0,他引:4  
The objective of the study was to validate the effectiveness of a questionnaire and computer-assisted algorithm in diagnosing children with dizziness or vertigo. Dizziness and vertigo are common complaints in children, causing an extensive, often unnecessary evaluation. A pediatric "dizziness questionnaire" was designed and a computer-assisted algorithm was developed to facilitate the diagnostic task. A retrospective medical record review was conducted on all children presenting to the clinic for dizziness or vertigo throughout a 2-year period. The information was used by one investigator to complete the questionnaire and by the other, the algorithm. The two diagnoses thus obtained were compared by the third investigator to the medical record diagnosis. Sixty-two records were reviewed. The final diagnoses were migraine (39%), benign paroxysmal vertigo (15%), vestibular neuronitis (14%), and anxiety (13%). In 57 patients (92%), the questionnaire-derived diagnosis was identical to the medical record diagnosis. In 52 patients (84%), the algorithm-derived diagnosis matched the medical record diagnosis. The questionnaire and computer-assisted algorithm are reliable diagnostic screening tools for children with dizziness or vertigo. When these tools combined provide a clear-cut diagnosis, no further evaluation is necessary.  相似文献   
993.
People with depression report frequent cognitive failures, but objective measures of cognition show mixed results. Some studies show impairment on effortful tasks. The relationship between subjective and objective cognitive failures was studied in 102 "depressed" or "nondepressed" UK servicemen, grouped by Beck Depression Inventory scores with a cutoff score of 10. Participants were administered cognitive tests including the Sustained Attention to Response Task (SART), a laboratory measure of vigilance that has revealed increased attentional lapses in traumatic brain injury patients. The depressed men made more errors on SART than the nondepressed men (P=0.012) but reported much higher incidences of cognitive failures on a standardized questionnaire (P=0.0001). The depressed men's SART reaction times slowed following an error, a pattern different from that of brain-injured subjects. Nonclinical depressed subjects may respond "catastrophically" to errors, heightening the subjective sense of failure and contributing to the strong relationship between subjectively reported cognitive failures and depression.  相似文献   
994.
BACKGROUND: Schizophrenia first appears in adolescence, in boys at an earlier age than girls. The interpretation of this key epidemiological finding crucially depends on whether similar age-related sex differences exist in the expression of associated, subclinical psychosis-like experiences. METHODS: Findings are based on a population sample of 2548 adolescents and young adults aged 17-28. Subjects were assessed with the core psychosis sections on delusions and hallucinations of the Munich-Composite International Diagnostic Interview. RESULTS: The risk of subclinical psychotic experiences was significantly higher for males in the younger half of the cohort (17-21 years), but similar in the older half (22-28 years). CONCLUSIONS: These findings suggest that normal maturational changes in adolescence with differential age of onset in boys and girls cause the expression of psychosis, the extreme of which is schizophrenia.  相似文献   
995.
Lee TM  Lam PK  Yee LT  Chan CC 《Neuroreport》2003,14(10):1361-1364
Previous findings suggested the facilitating effect of the electromagnetic field emitted by mobile phones on human attention. This study aimed to examine the relationship between the facilitating effect and the duration of exposure to the electromagnetic field emitted by mobile phones on human attention. Seventy-eight university students were randomly assigned to either an experimental or a control group. Their performance in the administered attention tasks was compared. Participants in the experimental group performed better on one of the two measures of attention only after they had been exposed to the electromagnetic field emitted by the mobile phone for some time. The results seem to suggest that attention functions may be differentially enhanced after exposing to the electromagnetic field emitted by mobile phones. Furthermore, this transient facilitation effect might be dose dependent.  相似文献   
996.
997.
Recessive mutations of sulfonylurea receptor 1 (SUR1) and potassium inward rectifier 6.2 (Kir6.2), the two adjacent genes on chromosome 11p that comprise the beta-cell plasma membrane ATP-sensitive K(+) (K(ATP)) channels, are responsible for the most common form of congenital hyperinsulinism in children. The present study was undertaken to identify the genetic defect in a family with dominantly inherited hyperinsulinism affecting five individuals in three generations. Clinical tests were carried out in three of the patients using acute insulin responses (AIRs) to intravenous stimuli to localize the site of defect in insulin regulation. The affected individuals showed abnormal positive calcium AIR, normal negative leucine AIR, subnormal positive glucose AIR, and impaired tolbutamide AIR. This AIR pattern suggested a K(ATP) channel defect because it resembled that seen in children with recessive hyperinsulinism due to two common SUR1 mutations, g3992-9a and delPhe1388. Genetic linkage to the K(ATP) locus was established using intragenic polymorphisms. Mutation analysis identified a novel trinucleotide deletion in SUR1 exon 34 that results in the loss of serine 1387. Studies of delSer1387 in COSm6 cells confirmed that the expressed mutant protein assembles with Kir6.2 and trafficks to the plasma membrane, but it had no (86)Rb efflux ion transport activity. These results indicate that hyperinsulinism in this family is caused by a SUR1 mutation that is expressed dominantly rather than recessively.  相似文献   
998.
The present study tests the hypothesis that higher consumption of bakery products, sweetened soft drinks and yogurt is associated with higher intake of energy, saturated fats, sugars and worse overall diet quality among Spanish children. This is a cross-sectional study covering 1112 children aged 6.0-7.0 years in four Spanish cities. Nutrient and food intake were obtained through a food-frequency questionnaire, and overall diet quality calculated using the healthy-eating index (HEI) developed by Kennedy et al. (1995). Standardized methods were used to measure anthropometric variables. Associations of interest were summarized as the difference in nutrient and food consumption between the value of the fifth and the first quintile of consumption (dq) of bakery products, sweetened soft drinks or yogurt, adjusted for energy intake and BMI. Bakery products, sweetened soft drinks and yogurt supplied 15.5, 1.0 and 5.6 % energy intake respectively. Higher consumption of these three foods was associated with greater energy intake (P<0.001), but not with higher BMI. Consumption of bakery products was associated with the proportion of energy derived from intake of total carbohydrates (dq 4.5 %, P<0.001) and sugars (dq 2 %, P<0.001), but did not show association with the HEI. Consumption of sweetened soft drinks was associated with a lower consumption of milk (dq -88 ml, P<0.001) and Ca (dq -175 mg/d, P<0.001), and worse HEI (dq -2, P<0.01). Consumption of yogurt, while associated with higher energy intake from saturated fats (dq 1.77 %, P<0.001) and sugars (dq 2.02 %, P<0.001), showed no association with the HEI. Differences in the intake of nutrients and foods across quintiles of consumption of bakery products, sweetened soft drinks and yogurt were usually very small. We conclude that the impact of the consumption of bakery products, sweetened soft drinks and yogurt on the quality of the diet of Spanish children is only modest, although it may contribute to aggravating certain unhealthy characteristics of their diet, particularly excess energy, saturated fats and sugars. Therefore, consumption of bakery products and sweetened soft drinks should be moderated, and priority given to consumption of low-fat, low-sugar yogurt.  相似文献   
999.
This study assessed whether sexual norms and attitudes expressed during early adolescence by minority youth from economically disadvantaged urban areas produce a sustained influence on the timing of sexual initiation. African American and Latino youth attending three middle schools were enrolled in the Reach for Health study in seventh grade and followed from an average age of 12.2 to 16.1 years. Some 849 respondents answered the question, "Have you ever had sexual intercourse" at four time points: fall seventh, spring seventh, spring eighth, and spring 10th grade. Culturally tailored scales assessed sex norms and outcome expectancies, sexual responsibility, and refusal attitudes at fall seventh grade. Influence of these norms and attitudes in early adolescence on timing of first reported sexual intercourse was examined using ANOVA controlling for gender. At fall seventh grade, 30.7% of boys and 7.7% of girls reported sexual intercourse; by spring 10th grade, the figures were 74.8% and 56.4%, respectively. Those reporting greater peer involvement in sex and more positive sex outcome expectancies were more likely to have initiated sex by fall seventh grade. Through 10th grade, the higher the scores on peer norms (f = 41.08, p < .0001) and outcome expectancies (f = 5.87, p = .002) at entry into seventh grade, the earlier the timing of initiation. Higher scores on sex responsibility at baseline were associated with delayed sexual intercourse (f = 7.36, p < .001), as are refusal attitudes (f = 15.62, p < .0001). Despite significant gender differences in timing of initiation and mean scale scores, these relationships were similar for males and females. Findings suggest the importance of addressing sexual norms and attitudes of minority youth in interventions to delay early sexual initiation in urban environments where this risk is high. Given their sustained influence on timing of sexual initiation, such interventions must begin prior to middle school and continue through mid-adolescence, years when early sexual experience can lead to negative health and social outcomes.  相似文献   
1000.
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