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排序方式: 共有4664条查询结果,搜索用时 15 毫秒
61.
Auricular infections caused by high ear piercing in adolescents 总被引:1,自引:0,他引:1
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High-density lipoprotein subclasses and esterification rate of cholesterol in children: effect of gender and age 总被引:1,自引:0,他引:1
M. Dobi ov Z. Urbanov H. Rauchov M. am nek JJ Frohlich 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(9):918-923
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
66.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Archives de pédiatrie》1998,5(12):1347-1352
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
67.
OBJECTIVES: To determine the predictors of bone mass (in lumbar spine and femoral neck) in healthy older men living in the community. DESIGN: Cross-sectional study. Bone mineral density (BMD) was measured and known predictors of bone mass and bone turnover were assessed. SUBJECTS AND SETTING: 113 independent, healthy men (70 years and over), not taking glucocorticoid therapy and without medical conditions known to affect bone mass and bone turnover, were recruited from recreational and sports clubs in southern Sydney in April/May 1997. MAIN OUTCOME MEASURES: BMD (measured by dual-energy x-ray absorptiometry); known predictors of bone mass (height; weight; body mass index; calcium level; serum 25-hydroxyvitamin D and free testosterone levels); and markers of bone turnover (serum bone Gla protein and procollagen-1 concentrations, and urinary deoxypyridinoline excretion rates). RESULTS: The mean age of the men was 76.6 years (range, 70-92 years). Mean (SE) BMD of the lumbar spine was 1.143 (0.019) g/cm2 and that of the femoral neck was 0.897 (0.013) g/cm2. BMD values indicating osteoporosis were found in the lumbar spine in 13 men (11.5%) and in the femoral neck in 35 men (31%). The best predictor of lumbar spine BMD was weight (R = 0.37; P = 0.001), and weight- and age-predicted femoral-neck BMD (R = 0.49; P < 0.001). The study group was analysed in two groups with BMD higher or lower than median bone mass corrected for age. Men with lower femoral-neck BMD for age had significantly lower weight, lower lean mass and higher bone Gla protein concentrations. In addition, men with lower lumbar spine BMD for age also had significantly lower fat mass. CONCLUSIONS: These data indicate that measures of body composition, such as weight and lean mass, are the main predictors of bone mass in healthy, community-dwelling older men. 相似文献
68.
JI Tang M Back T Shakespeare JJ Lu R Mukherjee C Wynne S Liang 《Journal of Medical Imaging and Radiation Oncology》2005,49(5):390-395
The aims were to determine the median survival and prognostic factors of patients with central nervous system (CNS) metastases managed with whole‐brain radiation therapy (WBRT), and to explore selection criteria in recently published clinical trials using aggressive interventions in CNS metastases. A retrospective audit was performed on patients managed with WBRT for CNS metastases. Potential prognostic factors were recorded and analysed for their association with survival duration. The proportion of patients with these factors was also compared with those of patients managed under three recently reported studies investigating aggressive interventions, such as radiosurgery and chemotherapy for CNS metastases. Seventy‐three patients were treated with WBRT for cerebral metastases over a 12‐month period. The median survival of the population was 3.4 months (95% confidence interval: 2.7–4.1), with 6‐ and 12‐month survival rates of 30 and 18%, respectively. Significant prognostic factors for prolonged median survival were Eastern Cooperative Oncology Group status 0–2 (P = 0.015), Medical Research Council neurological functional status 0–1 (P = 0.006), and Recursive Partitioning Analysis Class 2 versus Class 3 (P = 0.020). On multivariate analysis, younger patient age (P = 0.02) and better performance status (P < 0.01) were associated with improved outcome. When comparing these characteristics with selected published studies, our study cohort demonstrated a higher proportion of patients with poor performance status, a greater number of metastases per patient and a higher incidence of extracranial disease. This reflects the selected nature of patients in these published studies. Central nervous system metastases confer a poor prognosis and, for the majority of patients, aggressive interventions are unlikely to improve survival. The use of potentially toxic and expensive treatments should be reserved for those few in whom these studies have shown a potential benefit. 相似文献
69.
Naveenchandra Suryadevara Andrea R. Shiakolas Laura A. VanBlargan Elad Binshtein Rita E. Chen James Brett Case Kevin J. Kramer Erica C. Armstrong Luke Myers Andrew Trivette Christopher Gainza Rachel S. Nargi Christopher N. Selverian Edgar Davidson Benjamin J. Doranz Summer M. Diaz Laura S. Handal Robert H. Carnahan Michael S. Diamond Ivelin S. Georgiev James E. Crowe Jr. 《The Journal of clinical investigation》2022,132(11)
The protective human antibody response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) focuses on the spike (S) protein, which decorates the virion surface and mediates cell binding and entry. Most SARS-CoV-2 protective antibodies target the receptor-binding domain or a single dominant epitope (“supersite”) on the N-terminal domain (NTD). Using the single B cell technology called linking B cell receptor to antigen specificity through sequencing (LIBRA-Seq), we isolated a large panel of NTD-reactive and SARS-CoV-2–neutralizing antibodies from an individual who had recovered from COVID-19. We found that neutralizing antibodies against the NTD supersite were commonly encoded by the IGHV1-24 gene, forming a genetic cluster representing a public B cell clonotype. However, we also discovered a rare human antibody, COV2-3434, that recognizes a site of vulnerability on the SARS-CoV-2 S protein in the trimer interface (TI) and possesses a distinct class of functional activity. COV2-3434 disrupted the integrity of S protein trimers, inhibited the cell-to-cell spread of the virus in culture, and conferred protection in human angiotensin-converting enzyme 2–transgenic (ACE2-transgenic) mice against the SARS-CoV-2 challenge. This study provides insight into antibody targeting of the S protein TI region, suggesting this region may be a site of virus vulnerability. 相似文献
70.
In an attempt to identify oocytes at risk for polypronuclear fertilization, follicular fluids were obtained retrospectively that contained oocytes that fertilized normally and abnormally. Whenever possible, each patient served as her own control during the same stimulation cycle. Twenty-six of 169 patients had oocytes that became polypronuclear, and of those 26, 21 had oocytes that fertilized and cleaved normally. Follicular fluids were analyzed for estradiol, progesterone, androstenedione, transferrin, and insulin. Insulin levels were noted to be significantly elevated (P less than 0.05) in the polypronuclear group when compropose that insulin, a known growth factor for granulosa cells cultured in vitro, when present in excessive concentrations may predispose to polypronuclear fertilization. 相似文献