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11.
Alzheimer’s disease(AD)is a neurodegenerative disease that is characterized by an age-dependent progressive decline of memory,impairment of cognitive functions and changes in personality and behavior.Despite the improvement in understanding of the mechanisms underlying the disease,AD remains an incurable complex disorder with multifaceted pathophysiology to date.Apolipoprotein E(ApoE)is the main cholesterol carrier in the brain that supports lipid transport between brain cells.The individuals carrying the APOE4 allele are known to be at increased risk of developing AD compared with those carrying the more common APOE3 allele.  相似文献   
12.
Bone marrow imaging: magnetic resonance studies related to age and sex   总被引:9,自引:0,他引:9  
Measurements of T1 and T2 relaxation values and spin density of the lumbar vertebral bone marrow were performed in 212 patients, and the results were correlated with the patients' age and sex. T1 and T2 relaxation times for bone marrow in the lumbar vertebral bodies showed a progressive decrease with age for both sexes (except for the T2 relaxation values in female patients). The replacement of hematopoietic marrow by fatty marrow could explain the decrease in T1 and T2. The T1 and T2 values were in the same range for the first two age groups (age 1-10 years and age 21-40 years) and became slightly greater for the older female patients (age 51 years and older) than for the older males. This could be due to the loss of bone and mineral content, which is more rapid and significant for women. These normal T1 and T2 values may provide a baseline for future evaluation of diseases involving the lumbar spine.  相似文献   
13.
The validity of the Differential Ability Scales (DAS; Elliott, 1990) in predicting attention disorders in school-aged children was examined. The participants were 40 children diagnosed with attention deficit/hyperactivity disorder (ADHD) and 40 normal children between 7 and 12 years of age. Comorbidity was controlled by excluding children with ADHD who had a concurrent DSM-IV diagnosis such as reading disability, learning disability, mood disorder, or behavioral disorder. In addition, groups did not differ significantly by sex, age, racial/ethnic identification, or parental educational level. A stepwise discriminant analysis indicated the DAS correctly classified 72.5% of the total sample when either the Sequential and Quantitative Reasoning subtest or the Recall of Digits subtest was used to predict group membership. In general, the DAS core subtests were found to be good measures of cognitive ability in children classified with ADHD and did not appear to be influenced by attention problems.  相似文献   
14.
The determinants of the degree of metabolic decompensation at the diagnosis of type 1 (insulin dependent) diabetes mellitus (IDDM) and the possible role of diabetic ketoacidosis in the preservation and recovery of residual beta cell function were examined in 745 Finnish children and adolescents. Children younger than 2 years or older than 10 years of age were found to be more susceptible to diabetic ketoacidosis than children between 2 and 10 years of age (< 2 years: 53.3%; 2-10 years: 16.9%; > 10 years: 33.3%). Children from families with poor parental educational level had ketoacidosis more often than those from families with high parental educational level (24.4% v 16.9%). A serum C peptide concentration of 0.10 nmol/l or more was associated with a favourable metabolic situation. Low serum C peptide concentrations, high requirement of exogenous insulin, low prevalence of remission, and high glycated haemoglobin concentrations were observed during the follow up in the group of probands having diabetic ketoacidosis at the diagnosis of IDDM. Thus diabetic ketoacidosis at diagnosis is related to a decreased capacity for beta cell recovery after the clinical manifestation of IDDM in children.  相似文献   
15.
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores.  相似文献   
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17.

Background  

We aimed to determine how response to a parent-completed postal questionnaire measuring development, behaviour, impairment, and parental concerns and anxiety, varies in different European centres.  相似文献   
18.
Military medicine is the development within the art and science which is designed to carry out a specialized, essential and a highly significant mission under the adverse conditions of war. Low Intensity Conflict (LIC) is a mode of warfare which has come to stay and the Indian Military has to confront it as such. It is a campaign of nerves, less military and more psychological, with soldiers inevitably fighting with hands behind their back. The dichotomy the soldier faces, results in high levels of frustration leading to various stress disorders. The key in casualty survival lies in correct and timely psychological first-aid for which every section and platoon commander should be trained. Post Trauma Stress Disorder caused as a result of traumatic experience can deplete unit''s efficiency and therefore needs monitoring for early detection and treatment. Evolving medical strategies for Low Intensity Conflict Operations (LICO), therefore assumes significance.Key Words: Low Intensity Conflict, Post Traumatic Stress Disorder, Stress  相似文献   
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20.
OBJECTIVE: The role of human leukocyte antigen (HLA) DQB1 alleles and human papillomavirus (HPV) as contributing factors to invasive cervical cancer was investigated. To overcome problems of misleading causal inferences common in traditional case-control studies, a family-based test, the transmission/disequilibrium test, was used. METHODS: Ninety-six patients with pathologically confirmed invasive cervical cancer were ascertained. Human papillomavirus types were determined in 80 patients, of whom 81.25% were HPV-positive, and 18.75% were HPV-negative. Deoxyribonucleic acid was extracted from samples, taken from patients and their parents, and sequenced to determine DQB1 genotypes. Nuclear family data were used to test whether the DQB1 locus is associated with invasive cervical cancer while controlling for high-risk HPV-positive patients. The transmission/disequilibrium test evaluates whether the frequency of transmission of parental marker alleles to their affected offspring deviates from the expected Mendelian frequency of 50%. RESULTS: The HLA DQB1 locus showed evidence for allelic association with invasive cervical cancer in high-risk HPV-positive patients (P = .006). The transmission/disequilibrium test showed that the DQB1*0303 allele was transmitted to high-risk HPV patients more often than expected by chance, chi2(1) = 8.0, P = .005 (P = .035 when correcting for multiple tests). Tests of association were negative when applied to all 96 patients, irrespective of HPV status. No significant differences were found in the distribution of the DQB1 alleles among HPV-positive patients compared with those who were HPV-negative, indicating that HLA alleles are not associated with susceptibility to HPV infection. CONCLUSION: These results suggest that the DQB1*0303 allele increases the risk for invasive cervical cancer in women who are HPV-positive.  相似文献   
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