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51.
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   
52.
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   
53.
54.
放疗联合肝动脉化疗栓塞治疗肝癌的研究进展   总被引:3,自引:1,他引:3  
对于不能手术的原发性肝癌患者,放射治疗配合肝动脉栓塞化疗(TACE)的疗效明显好于单纯放疗或单纯化疗,治疗并发症的发生率和程度可以接受,大多数患者可以耐受。放疗配合动脉栓塞化疗是治疗不能手术的原发性肝癌患者的非常有发展前途的治疗方法。现综述这二种治疗方法的技术特点、疗效和协同作用研究的现状及最新进展。  相似文献   
55.
目的 探讨三七、茜草(SQ)复方治疗置铜宫内节育器(Cu-IUD)所致子宫异常出血的作用机理。方法 制 作家兔置Cu-IUD动物模型,以吲哚美辛作对照,观察SQ复方对置Cu-IUD家兔模型子宫匀浆中组织型纤溶酶原激 活物(t-PA)活性的影响。结果 置Cu-IUD家兔模型子宫匀浆中t-PA的含量增高(P<0.01),经SQ复方治疗后与模 型组比较有显著性差异(P<0.01),说明SQ复方能减少家兔子宫匀浆中t-PA的含量,降低t-PA的活性。结论 SQ 复方通过降低置Cu-IUD家兔子宫内膜局部的纤溶活性而达到止血的目的。  相似文献   
56.
背景与目的:颅叫管瘤为难治性肿瘤,其预后不良,复发机制尚不清楚。本研究检测颅Ⅱ阏管瘤组织中微血管密度(microvascular density,MVD)及血管内皮生长因子vascular endothelial growth factor,VEGF表达.分析其与肿瘤预后等生物学行为的关系。方法:采取前瞻性队列研究方案,经纳入、排除标准筛选卅颅咽管釉质上皮型肿瘤32例、鳞形乳头瘤型肿瘤31例,平均随访843个月,收集原发及复发患者的肿瘤组织标本,应用单克隆抗体CD34、VEGF抗体检测肿瘤组织MVD及VEGF蛋白表达,计算机辅助成像系统对其作出定量分析,分析其与肿瘤复发等生物学行为的关系。结果:VEGF蛋白、MVD计数在颅咽管瘤队列复发组、非复发组间不具有显著性差异(P〉0.05),而在颅咽管瘤不同病理类型间差异则具有显著性(P〈0.05)。结论:VEGF蛋白、MVD计数与肿瘤复发无关,不能预测颅咽管瘤复发的危险性,但可为了解肿瘤的同有侵袭性行为提供参考。  相似文献   
57.
分化型甲状腺癌(DTC)在全部甲状腺癌类型中最为常见,占94%以上。目前主要采取根治性手术切除、选择性放射(131I)治疗和促甲状腺激素(TSH)抑制治疗的综合治疗,总体预后较好。TSH能够与DTC细胞表达的TSH受体结合,刺激DTC细胞生长,因此TSH抑制治疗是减少DTC患者术后肿瘤复发风险的重要环节,已得到国内外多项指南的明确推荐。但在临床实践中,仍存在部分患者难以实现TSH抑制治疗目标,需要反复调整治疗剂量以达到预期目标,治疗过程中可能伴随乏力、嗜睡或心悸等不适。本文主要总结DTC术后TSH抑制治疗疗效的影响因素,以期帮助临床医生为DTC患者提供更好的术后TSH抑制治疗和随访管理,以提高患者生活质量,延长远期生存时间,降低DTC术后复发率。  相似文献   
58.
The rGO/CeO2/FTO nanocomposite modified electrode was prepared by an electrochemical method. A simple and highly sensitive electrochemical sensing platform for electrochemical rGO and modified CeO2 nanoribbons directly on FTO electrodes was developed. Simultaneous determination of Pb2+ and Cd2+ used the differential pulse anodic stripping voltammetry (DPASV) method. The method was simple to operate, and CeO2 nanobelts could be obtained simultaneously by electrodeposition and reduction of GO without further processing. This is an environmentally friendly electrochemical method to obtain modified electrodes under mild conditions. The experimental results showed that the linear calibration curves of Pb2+ and Cd2+ are 1–300 and 0.2–500 μg L−1, respectively. At the same time, no interference from other coexisting metal ions was found during the detection process, which proved that the modified electrode had good stability and repeatability.

The rGO/CeO2/FTO nanocomposite modified electrode was prepared by an electrochemical method.  相似文献   
59.
BackgroundSialorrhea in children can be associated with adverse physical and social effects. Treatment using anticholinergic medications has been shown to offer symptomatic relief, but there is no consensus regarding which treatment is the most efficacious.ObjectiveTo examine the effectiveness of anticholinergic medications for sialorrhea in children.MethodsA systematic review was carried out in Medline, EMBASE, Cochrane, Scopus, and the Web of Science from inception until April 29, 2020. Studies reporting original data on the efficacy of anticholinergic medications in the management of sialorrhea in children aged 0 to 17 years of age were included. This review adhered to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) standards. Data on study design, setting, population, pharmacologic intervention(s), comparator(s), outcomes, and results were extracted and summarized.ResultsThe search strategy identified 2,800 studies of which 27 articles were included in the synthesis, including five randomized controlled trials. Each anticholinergic undergoing experimental study (glycopyrrolate, scopolamine/hyoscine, trihexyphenidyl/benzhexol, benztropine, and atropine) showed evidence of efficacy. Adverse side effects were common. Significant heterogeneity exists in the studies’ methodology and the variability of outcome measures used between studies precluded a meta-analysis.ConclusionsGlycopyrrolate, scopolamine/hyoscine, trihexyphenidyl/benzhexol, benztropine, and atropine have all shown efficacy in the treatment of sialorrhea in children. The small number of reports and the variability in study design precluded a meta-analysis. More studies are needed with uniformity in outcome measures to help guide evidence-based decision making. A guidance table is presented.  相似文献   
60.
Current public health advice is that high ultraviolet radiation (UVR) exposure is the primary cause of Malignant Melanoma of skin (CMM), however, despite the use of sun-blocking products incidence of melanoma is increasing. To investigate the UVR influence on CMM incidence worldwide WHO, United Nations, World Bank databases and literature provided 182 country-specific melanoma incidence estimates, daily UVR levels, skin colour (EEL), socioeconomic status (GDP PPP), magnitude of reduced natural selection (Ibs), ageing, urbanization, percentage of European descendants (Eu%), and depigmentation (blonde hair colour), for parametric and non-parametric correlations, multivariate regressions and analyses of variance. Worldwide, UVR levels showed negative correlation with melanoma incidence (“rho” = −0.515, p < 0.001), remaining significant and negative in parametric partial correlation (r = −0.513, p < 0.001) with other variables kept constant. After standardising melanoma incidence for Eu%, melanoma correlation with UVR disappeared completely (“rho” = 0.004, p = 0.967, n = 127). The results question classical views that UVR causes melanoma. No correlation between UVR level and melanoma incidence was present when Eu% (depigmented or light skin type) was kept statistically constant, even after adjusting for other known variables. Countries with lower UVR levels and more Eu% (depigmented or light skin people) have higher melanoma incidence. Critically, this means that individual genetic low skin pigmentation factors predict melanoma risk regardless of UVR exposure levels, and even at low-UVR levels.  相似文献   
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