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61.
Summary In this paper, we study marginal and conditional skewness in financial returns for nine time series of major international stock indices. For this purpose, we develop a new variant of the GARCH model with dynamic skewness and kurtosis. Our empirical results indicate that there is no evidence of marginal asymmetry in the nine time series under consideration. We do however find significant time‐varying conditional skewness. The economic significance of conditional skewness is analysed in terms of Value‐at‐Risk measures and Market Risk Capital Requirements set by the Basel Accord.  相似文献   
62.

Background  

Early diagnosis of dementia benefits both patient and caregiver. Nevertheless, dementia in primary care is currently under-diagnosed. Some educational interventions developed to improve dementia diagnosis and management were successful in increasing the number of dementia diagnoses and in changing attitudes and knowledge of health care staff. However, none of these interventions focussed on collaboration between GPs and nurses in dementia care. We developed an EASYcare-based Dementia Training Program (DTP) aimed at stimulating collaboration in dementia primary care. We expect this program to increase the number of cognitive assessments and dementia diagnoses and to improve attitudes and knowledge of GPs and nurses.  相似文献   
63.
青蒿素(1)是从青蒿(Artemisia annua)中分离得到的一个抗疟化合物。青蒿素的发现改变了以往抗疟药物均为含氮杂环化合物的格式,开创了一类以过氧化合物为特征的、对抗氯喹虫株有效的新型抗疟药物。七十年代青蒿素结构发表以来,国内外在化学、药理以及临床方面均进行了大量工作,成为当今抗疟药方面最活跃的一个研究课题。这里简要报道  相似文献   
64.
Summary We have studied the effects of i.v. dexamethasone and oral prednisone on plasma cholinesterase (ChE) activity in 13 male and 10 female patients during long-term treatment with dexamethasone or prednisone.A decrease in ChE activity — probably due to inhibition of ChE synthesis in the liver — was seen in all the patients. In individual patients there was a drop in enzyme activity of 14–57% (dexamethasone) and 23–69% (prednisone) respectively, compared with individual control values.After withdrawal of dexamethasone, ChE activity in most cases increased to above control values and the period necessary for complete restoration of ChE activity was variable (between 25–70 days).Our results suggest that the decrease in ChE activity in patients treated with dexamethasone or prednisone depends on the initial dose of the drug as well as on the duration of treatment.  相似文献   
65.
激光治疗瘢痕的特征   总被引:3,自引:0,他引:3  
目的:介绍国内近20年来激光治疗瘢痕的临床研究概况,以期进一步了解激光治疗瘢痕的新进展。资料来源:应用计算机检索Pubmed和中国生物医学文献数据库1983/2006的相关文章,限定文章语言种类为英文和中文,检索词为“cicatrices(瘢痕),laser(激光)”。资料选择:对资料进行初审,选择临床试验研究文献查找全文。纳入标准:①有明确诊断标准。②随机对照实验或对照试验。有无随访,是否采用盲法不限制。③治疗组干预措施为激光或激光联合药物;对照组干预措施为曲安奈德、冷冻联合曲安奈德或不采用药物措施。排除标准:①非对照研究。②治疗组或对照组的干预措施不符合纳入标准。③机制研究。④重复研究。资料提炼:共收集到相关文献120篇,按上述标准纳入31篇,其余文献均被排除。资料综合:31篇文章中11篇为随机对照研究,10篇为对照研究,各研究的研究期为1~6个月。各研究所纳入的病例数量为10~50例。其中6个研究对比了激光与传统药物治疗瘢痕的疗效及安全性,2个研究进行了激光治疗瘢痕基础研究机制比较,10个研究观察了激光结合与单纯药物或单纯激光对瘢痕的疗效,4个研究比较了激光联合西药治疗瘢痕的疗效,2个研究观察了激光治疗瘢痕的副作用。7篇介绍国内或国外瘢痕治疗的研究情况。结论:激光治疗瘢痕的疗效可靠,具有副作用少,方法简单,安全性高,易被患者接受等优势。但由于激光治疗瘢痕还存在着一定的局限性,今后还需要在激光的穿透深度方面研究。  相似文献   
66.
67.
Transcutaneous electrical nerve stimulation (TENS) is a commonly utilized non-pharmacological, non-invasive treatment for pain. GABA is a neurotransmitter in the dorsal horn of the spinal cord that mediates analgesia locally, and also through activation of supraspinal sites. TENS reduces hyperalgesia through activation of receptor-mediated pathways at the level of the spinal cord, and supraspinally. The current study tested the hypothesis that either high or low frequency TENS applied to the inflamed knee joint increases GABA in the spinal cord dorsal horn and activates GABA receptors spinally. We utilized microdialysis to sample the extracellular fluid before, during and after TENS and analyzed GABA in dialysates with high performance liquid chromatography. We analyzed the extracellular GABA concentrations in animals with and without knee joint inflammation induced by intra-articular injection of kaolin and carrageenan. We further tested if spinal blockade of GABA receptors prevents the antihyperalgesia produced by TENS in rats with joint inflammation. We show that high frequency TENS increases extracellular GABA concentrations in the spinal cord in animals with and without joint inflammation. The increases in GABA do not occur in response to low frequency TENS, and there are no increases in glycine in response to low or high frequency TENS. However, the reduction in primary hyperalgesia by both high and low frequency TENS is prevented by spinal blockade of GABA(A) receptors with bicuculline. Thus, high frequency TENS increases release of GABA in the deep dorsal horn of the spinal cord, and both high and low frequency TENS reduce primary hyperalgesia by activation of GABA(A) receptors spinally.  相似文献   
68.
The LDL receptor-associated protein (RAP) is involved in secretion of thyroglobulin (Tg) from the thyrocyte to the colloid. Disruption of the RAP gene in mice results in a reduced Tg content within the colloid, leading to subclinical hypothyroidism and histological alterations resembling early goiter. Here we studied the entire coding sequence of RAP in genomic DNA samples from 18 patients with primary hypothyroidism not due to thyroid autoimmunity or dysgenesis. The control group included 21 subjects with no evidence of thyroid alterations. Eleven different polymorphisms with amino-acid substitution and 4 different missense polymorphisms without amino-acid substitution were found in various regions of the RAP gene. Only one polymorphism in exone 7 (V311M) was observed exclusively in patients, but it had been previously reported in normal subjects as well. The remaining polymorphisms were found either both in patients and controls or only in controls and had not been previously reported. The frequency of the various polymorphisms did not differ significantly between patients and controls. Based on these findings, we conclude that alterations of the RAP gene are not a common cause of hypothyroidism, although it cannot be excluded that other, rarer alterations with a pathogenic effect exist, and that they should be investigated in a larger number of patients.  相似文献   
69.
An inherited, interstitial subtelomere deletion of approximately 1.3–1.4 Mb at 3q29 was identified in a patient and his father utilizing BAC array comparative genomic hybridization (a-CGH). The imbalance was located within the common 3q29 microdeletion syndrome region and shared the distal breakpoint with prior published cases. However, our patient was developmentally normal at 6 months of age and his father is a functional adult, who had mild developmental delay in childhood. They presented with congenital cardiac defects including patent ductus arteriosus. In addition, the patient had subvalvular aortic stenosis and his father had pulmonic stenosis. These defects were not present in most of the previously reported 3q29 microdeletion cases. This case expands the phenotypic findings associated with 3q29 microdeletion syndrome, suggesting an association with cardiac defect. It also raises the possibility of normal cognition in adulthood.  相似文献   
70.
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