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81.
To determine the prevalence of thyroid hormone abnormalities and generalized resistance to thyroid hormone in a population of children with attention deficit hyperactivity disorder (ADHD) as compared to reference ranges determined from a control population and hence to determine if routine thyroid hormone screening in children with non-familial ADHD is indicated.

Method:


Children attending the State Child Development Centre in Perth, Western Australia with ADHD, as defined by the Diagnostic and Statistical Manual of Mental Disorders (fourth edition) provided the study population. The control population consisted of 353 normal children with a history of allergy in whom radioallergosorbent (RAST) testing was being performed.

Results:


The prevalence of thyroid hormone abnormalities in the study population was 2.3% (95% CI 0.6%, 5.7%). There were no cases of generalized resistance to thyroid hormone. The prevalence of thyroid hormone abnormalities in the general population of children and adolescents has been reported to vary between 1 and 3.7%.

Conclusion:


Routine thyroid hormone screening is not indicated in children with non-familial ADHD.  相似文献   
82.
Auricular infections caused by high ear piercing in adolescents   总被引:1,自引:0,他引:1  
  相似文献   
83.
6名健康妇女分别于上臂、臀部和腹部三部位经皮给予合LNG的透皮控释传递系统(TCDS)后,用放射免疫法测定LNG血清浓度,计算其主要药物动力学参数。结果表明:在TCDS用药期间,三部位的C(max)、T(max)及AUC(0~168h)基本接近,部位间无显著性差异(P>0.05);TCDS揭除后,AUC(168~204h)及消除相半衰期T(1/2)(Ke)均以腹部最大,臀部次之,上臂最小,在腹部与上臂间有显著性差异(P<0.05)。上述结果可归因于TCDS对LNG的控释和人体皮下脂肪的“贮库效应”。  相似文献   
84.
Since the development of coronary heart disease (CAD) is affected by a specific pattern of plasma high density lipoprotein (HDL) effects it may be useful to know whether this occurs already in childhood. In this study we evaluated particle size distribution of HDL by gradient gel electrophoresis and the determination of cholesterol esterification rate (FERHDL) in plasma depleted of apo B lipoproteins in 221 children (108 boys and 113 girls) aged 4 months to 20 years. Total plasma- (TC), low-density lipoprotein- (LDL-C) and HDL- (HDL-C) cholesterol, HDL unesterified cholesterol (HDL-UC) and plasma triglycerides (TG) were also measured. There were no significant gender and age differences with respect to the plasma TC, LDL-TC and TG but concentration of HDL-TC increased with age. Post-pubertal girls had significantly higher relative concentrations of HDL2b compared to boys (30.4% vs 17.2%), while HDL3b,c was lower in post-pubertal girls (8.7% vs. 16.5 %). FERHDL correlated inversely with HDL2b and positively with HDL3b,c particles and was significantly higher in boys of the post-pubertal group compared to girls (16.9%/h vs 12.5%/h). While in girls there was a positive correlation between age and HDL-C, HDL-UC and the relative concentration of HDL2b no significant correlation were observed in boys. In girls the increase in TC showed a significant correlation with a simultaneous increase in HDL-C, HDL-UC and HDL2b. In boys TC correlated significantly with changes in TG only. When HDL2b and HDL3b,c cholesterol levels are calculated from HDL-C concentration and per cent distribution the differences between males and females are further emphasized. These data indicate that HDL particle size distribution is age- and gender-dependent.  相似文献   
85.
86.
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus.  相似文献   
87.
Dentate gyrus granule cells from immature (7-28 days) Sprague-Dawley rats were examined with whole cell patch clamp recordings and biocytin filling in in vitro hippocampal slice preparations. Although recordings were confined to the middle third of the suprapyramidal limb of the dentate, the granule cells exhibited marked variability in their physiologic properties: input resistance (IR) ranged from 250 MOmega to 3 GOmega, and resting membrane potential (RMP) from -82 to -41 mV. Both IR and RMP were inversely correlated with dendritic length, a morphometric indicator of cell maturity. Thus the highest IR cells were the youngest, and maturation was characterized by a progressive decrease in IR, hyperpolarization of RMP, and elongation of the dendritic arbor. When cells were grouped by IR, significant intergroup differences were found in RMP, dendritic length, and number of dendritic terminal branches. Although cells of all IR categories were examined throughout the age spectrum under study, none of the inter-IR group differences was age-dependent. These data suggest that IR provides a reasonable estimate of granule cell maturity and that maturation entails predictable changes in cell properties and morphology. These aspects of maturation correlate with each other, are independent of animal age, and most likely proceed according to a program related to cell birth.  相似文献   
88.
Ye J 《Brain research》2000,862(1-2):74-82
Properties of whole-cell glycine-activated currents (I(Gly)) of neurons freshly isolated from ventral tegmental area of rats between postnatal day (P) 0 and 40 (P0-P40) were examined using the gramicidin-perforated patch technique. I(Gly) was present throughout the period of investigation and displayed age-related alternations in its kinetics, reversal potentials (E(Gly)) and sensitivity to antagonists. During development, the time constant for desensitization of I(Gly) decreased about two-fold, and the E(Gly) shifted to more negative potentials. Specifically, E(Gly) was -29 mV in neonatal (P0-P7) and decreased to -50 mV in adult (P24-P40) neurons. While the neonatal glycine receptors (GlyRs) are resistant to strychnine, the adult GlyRs are sensitive to STR. The values for 50% inhibition (IC(50)) of I(Gly) was 110 and 12 nM in P0-P3 and P24-P40 neurons, respectively. Picrotoxin, on the other hand, was more effective in blocking neonatal neurons. The IC(50) values were 17 and 231 microM for the neonatal and adult neurons, respectively. These observations are discussed in terms of developmental changes of subunit composition of GlyRs and of intracellular Cl(-) concentrations.  相似文献   
89.
全肠外营养对早产儿营养、免疫功能及行为发育的影响   总被引:6,自引:1,他引:6  
【目的】探讨全肠外营养(TPN)对早产儿营养、免疫功能及行为发育的影响。【方法】监测55例TPN治疗早产儿的营养状况、肝肾功能、血脂水平、免疫功能及矫正胎龄40周时行为发育情况,并与25例未行TPN的早产儿对照分析。【结果】TPN治疗组体重增长快、体重日增长及治疗后体重高于对照组,TPN治疗后血清蛋白、免疫球蛋白及补体水平升高,肝肾功能及血脂检查无明显异常,矫正胎龄40周时NBNA评分高于对照组。【结论】TPN能改善早产儿营养状况、促进免疫水平的提高和行为神经的发育,对早产儿的治疗有重要意义。  相似文献   
90.
临床瞳孔检查新进展   总被引:2,自引:1,他引:2  
瞳孔每时每刻处于动态的变化之中,因此瞳孔的检查也是一个较为复杂的过程。随着对屈光手术质量要求的日益提高,特别是暗适应下瞳孔的大小往往在一定程度上可能决定着术后质量的好坏,因此暗适应下瞳孔的精确测量变得尤为重要。现对近年来涌现的瞳孔检查新技术作一简要概括。  相似文献   
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