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61.
儿童胫后神经刺激的体感诱发电位正常值及其特点   总被引:4,自引:0,他引:4  
探讨儿童体感诱发电位的正常值。对30例8-14岁健康儿童记录和测量了刺激胫扣神经引起的脊髓和皮层SEPs正常值,并计算出胫后神经4 传导速度。结果1.SEPS各波潜伏期与身高均呈高度正线怀相关,与年龄,体重亦呈正相关,而潜伏期与年龄,体重的正相关是由身高引起的。2.P40-N20波间期与身高,年龄,体重均无显著相关关系。结论,SEPS潜伏期正常值应按其与身高的回归方程确定,P40-N20波间期正常  相似文献   
62.
Abstract: It seems clear that the pineal hormone, melatonin (N-acetyl-5-methoxytryptamine), is involved in the reproductive behavior of several animal species including humans. Moreover, several data also support a role for 5-methoxytryptophol (ML), another pineal hormone, in the control of sexual processes. To test the role of ML in human reproductive axis, 128 healthy children, 68 boys and 60 girls, were studied. Each of these groups was divided in three age subgroups of 6, 11, and 14 years. A single blood sample (0900 hours) was obtained from each subject to determine melatonin, ML, FSH, LH, estradiol (girls), and testoterone (boys) by RIA. Statistical analysis of the data included ANOVA-II (factor I: age, factor II: sex) and an analysis of covariance with age as covariate. A similar plasma melatonin concentration, with a significant decrease between 6 and 11 years, was found in boys and girls. Melatonin concentrations correlate well with initiation of the pubertal development in these children, although no sex differences were found. Concentrations of ML are approximately 50% of those of melatonin. In contrast to melatonin, ML levels show significant age and sex differences. Plasma ML concentration significantly increased in boys ( P < 0.001) and decreased in girls (P < 0.001) after 8 years of age. These results support the hypothesis that, besides melatonin, other pineal compounds such as ML may be involved in the maturation process in humans. The pineal indole ML may also be used as a marker of the different chronobiology in the pubertal development in boys and girls.  相似文献   
63.
Before meaningful conclusions can be drawn from clinical measures of cerebral blood perfusion, the precision of the measurement must be determined and set in the context of inter- and intrasubject sources of variability. This work establishes the reproducibility of perfusion measurements using the noninvasive MRI technique of continuous arterial spin labeling (CASL). Perfusion was measured in 34 healthy normal subjects. Intersubject variability was assessed, and age and gender contributions were estimated. Intersubject variation was found to be large, with up to 100% perfusion difference for subjects of the same age and gender. Repeated measurements in one subject showed that perfusion remains remarkably stable in the short term when compared with intersubject variation and the large capacity for perfusion change in the brain. A significant decrease in the ratio of gray-matter to white-matter perfusion was found with increasing age (0.79% per year (P < 0.0005)). This appears to be due mainly to a reduction in gray-matter perfusion, which was found to decrease by 0.45% per year (P = 0.04). Regional analysis suggested that the gray-matter age-related changes were predominantly localized in the frontal cortex. Whole-brain perfusion was 13% higher (P = 0.02) in females compared to males.  相似文献   
64.
Electroretinograms and retinal oscillatory potentials to full-field flash stimulation were recorded by dermal electrodes in a population of subjects (1 to 84 yrs) balanced for age and sex (119 females, 133 males), without evidence or history of ocular and/or relevant systemic diseases. The electroretinogram latencies and b-wave amplitude increased, while the a-wave amplitude decreased linearly with age. The oscillatory potential amplitude initially increased, to decrease approximately at the age of 50, with an inverted U-shaped distribution.Presented in part at the XXV ISCEV Symposium, Sarasota (Florida), April 26–30, 1987.  相似文献   
65.
In 7 patients (5 girls, 2 boys) with the EMG or Wiedemann-Beckwith syndrome, statural growth, bone age (BA), weight and pubertal development were studied longitudinally. Height was above the 90th percentile (%) for chronological age (CA) after age 2 years, reaching an average of 2.5 SD above the mean at or after puberty. Adult or attained height also exceeded significantly (P<0.015) parental (genetic) target height by 13.2 cm on the average. In one girl, adult height prognosis (190 cm) could be reduced to an adult height of 183 cm by high-dose estrogen treatment. In most children, growth velocity remained above the 90th % up to 4–6 years of age and normalized thereafter. In all patients studied, bone age was markedly advanced and particularly so during the first 4 years after birth. Weight was above the 90th–97th % during infancy and early childhood and remained there, appropriate or slightly subnormal for height, until adulthood, except for 3 girls who reached and maintained the 50th % during or after puberty. Spontaneous pubertal development occurred within normal limits for CA and around the 50th % for BA. Except for the marked bone age acceleration, the reason for the increased statural growth and adult height in patients with the EMG syndrome is still unknown.  相似文献   
66.
To assess the magnitude and nature of interpersonal violence resulting in hospitalisation of children and to identify subgroups at risk of repeat hospital admissions, a population-based, retrospective study of all violence hospitalisations in Western Australia for children aged 9 years or less was undertaken, using the 1990–2004 linked data retrieved from the Western Australian Mortality Database and the Hospital Morbidity Data System.
Of the 747 patients aged <10 years incurring 834 hospitalisations for the consequences of violence during the study period, 570 (76%) were less than 4 years of age. A total of 43 deaths from violence were recorded and 74 (9%) patients were admitted for more than one episode of violence. Victims aged 0–4 years from rural (hazard ratio [HR] = 2.72; 95% confidence interval [CI] 1.35, 5.43) and remote parts (HR = 2.79; 95% CI 1.25, 6.25) of the state were at increased risk of a subsequent admission for violence compared with those residing within the metropolitan area. Indigenous children aged 5–9 years were significantly more likely (HR = 3.57; 95% CI 1.14, 11.13) to incur a second hospitalisation for violence than their non-Indigenous counterparts. The identification of young victim subgroups at high risk of repeat hospitalisations is important for developing intervention strategies to reduce the burden of interpersonal violence. Young children aged 0–4 years living in rural and remote locations and Indigenous children aged 5–9 years should be specifically targeted for attention.  相似文献   
67.
AIMS: To examine the association between maternal glycated haemoglobin in the second half of diabetic pregnancies and the relative risk of delivering large-for-gestational-age (LGA) babies, controlling for maternal body mass index (BMI) before pregnancy, weight gain, age, White class and smoking habits. METHODS: We identified all pregnant diabetic women in North Jutland County, Denmark from 1985 to 2003. Data on HbA(1c) values from the 20th gestational week to term were collected from medical records and the babies were classified as large, normal or small for gestational age. The association between glycated haemoglobin (HbA(1c)) and relative risk of delivering an LGA baby was quantified based on logistic regression models and stratified analysis controlling for the five covariates. RESULTS: We included 209 singleton pregnancies with assessable HbA(1c) values of which 59%[95% confidence interval (CI) 52-65%] terminated with an LGA baby. Increasing levels of HbA(1c), BMI and weight gain were all associated with increasing risk of delivering an LGA baby. Analyses stratified according to maternal BMI showed that the association between HbA(1c) and risk of delivering an LGA baby was restricted to pregnancies with pre-pregnancy BMI > 23 kg/m(2). We found no association between HbA(1c) and risk of delivering an LGA baby in pregnancies with lower BMI. CONCLUSION: The positive association between glycated haemoglobin and birth of an LGA baby seems to be restricted to women with BMI > 23 kg/m(2).  相似文献   
68.
This study focuses on differences in health and social service use in the last 2 years of life among Finnish people aged 70–79, 80–89, and 90 or older and on the variation in service use in the various municipalities. The data set, derived from multiple national registers, consists of 75,578 people who died in 1998–2001. The services included hospitals and long-term-care facilities, use of regular home care, and prescribed medicines. General hospital and public long-term care were the services most commonly used: general hospitals for younger age groups and public long-term care for older groups. The number of inpatient days in hospital was lower with increasing age, but older age groups used long-term care more frequently. Men had more hospital inpatient days than women, but women used more long-term care. The number of hospital inpatient days increased rapidly in the last months of life, almost doubling in the final month. Days in public long-term care increased regularly in the last 2 years of life. Variation in both hospital and long-term care by municipality was remarkable. The results indicate that, among people aged 70 years and older, age is a major determinant of care in the last 2 years of life. The variation in the use of care by municipality and the differences between men and women deserve more detailed analysis in future.  相似文献   
69.
Since the end of the 2nd World War, Japan has seen quite rapid socioeconomical development. With this development the physical size of Japanese children has increased, but the final size, especially the stature, is still shorter than that of Americans or Europeans. Bone maturation velocities were compared among Japanese and Chinese children and adolescents aged 7 to 18 (in 1986) and English TW2-subjects, using the TW2 method. Asian children and adolescents may have a different tempo of skeletal maturation during pubertal growth from that of English children and adolescents. This, probably genetic, difference in the tempo of skeletal maturation, especially that of RUS, between Japanese and English during pubertal growth may be one of the main causes of the final difference in the stature of the two groups.  相似文献   
70.
胎儿主要肢骨发育时间表──超声骨龄   总被引:1,自引:0,他引:1  
用B超检测正常妊娠中的胎儿。选择受精龄为12至38整周(completedweek)的胎儿297例。测量其主要肢骨(干)长度。并将所测数据进行统计学处理。结果表明胎儿肢骨的生长发育与胎龄有显著的正相关关系。  相似文献   
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