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广西藤茶中黄酮类成份的提取工艺研究   总被引:18,自引:0,他引:18  
目的:提取分离藤(Ampelosis grossdentata)中的双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin)。方法:采用新的水提取和溶剂分离的方法,经化学和光谱鉴定确定结构。结果:提取产物经确证为双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin),平均收率分别为19.6%和0.51%。结论:该提取法经济、简便,易于操作并且提取率  相似文献   
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Objective To illustrate the use of percutaneous ultrasound-guided biopsy of the gastrointestinal tract in HIV-infected patients to obtain a tissue diagnosis.
Design The technique was used in relation to relevant clinical situations in which a diagnosis may have only been reached by open biopsy.
Method Three HIV-infected patients with suspected gastrointestinal tract lesions underwent percutaneous ultrasound-guided biopsy under local anaesthetic.
Results A tissue diagnosis was made in each case resulting in initiation or continuation of appropriate therapy and avoided the need for open biopsy under general anaesthetic.
Conclusion Although the number of patients undergoing the procedure in this series was small, the technique has so far been shown to be safe and effective with few complications.  相似文献   
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Background  

Injuries in or around the home are the most important cause of death among children aged 0-4 years old. It is also a major source of morbidity and loss of quality of life. In order to reduce the number of injuries, the Consumer Safety Institute introduced the use of Safety Information Leaflets in the Netherlands to provide safety education to parents of children aged 0-4 years. Despite current safety education, necessary safety behaviours are still not taken by a large number of parents, causing unnecessary risk of injury among young children. In an earlier study an E-health module with internet-based, tailored safety information was developed and applied. It concerns an advice for parents on safety behaviours in their homes regarding their child. The aim of this study is to evaluate the effect of this safety information combined with personal counselling on parents' child safety behaviours.  相似文献   
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Non-melanoma skin cancer (NMSC) represents the most frequently diagnosed malignancy worldwide, most being cutaneous basal cell and squamous cell carcinoma. The global incidence of NMSC continues to increase as the global population ages. Numerous treatment options are available for NMSC patients, with radiotherapy an efficacious and tissue-preserving non-surgical option. External beam radiotherapy and brachytherapy are modalities with specific indications and advantages in treating NMSC. Where excision is not an option (medically/technically inoperable) or considered less ideal (e.g. cosmetic or functional outcome), radiotherapy offers an excellent alternative. Inoperable elderly and/or co-morbid patients of poor performance status can benefit from short-course hypofractionated radiotherapy, with very acceptable toxicity. Adjuvant radiotherapy in patients with unfavourable pathology can decrease the risk of local and regional recurrence and associated morbidity and mortality. Radiotherapy has advantages and disadvantages and it is important for clinicians to understand these. Managing patients with NMSC is carried out by clinicians from multiple disciplines but it is imperative that they are all aware of the role of radiotherapy in their patients in various clinical settings. Here we aim to discuss the role and indications for recommending radiotherapy in patients with NMSC.  相似文献   
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BACKGROUND AND PURPOSE: Hyperglycemia can lead to an increased rate of apoptosis of microglial cells and to damaged neurons. The relation between hyperglycemia and cerebrovascular markers on MRI is unknown. Our aim was to study the association between intraoperative hyperglycemia and cerebrovascular markers.METHODS: In this further analysis of a subgroup investigation of the BIOCOG study, 65 older non-demented patients (median 72 years) were studied who underwent elective surgery of ≥ 60 minutes. Intraoperative blood glucose maximum was determined retrospectively in each patient. In these patients, preoperatively and at 3 months follow-up a MRI scan was performed and white matter hyperintensity (WMH) volume and shape, infarcts, and perfusion parameters were determined. Multivariable logistic regression analyses were performed to determine associations between preoperative cerebrovascular markers and occurrence of intraoperative hyperglycemia. Linear regression analyses were performed to assess the relation between intraoperative hyperglycemia and pre- to postoperative changes in WMH volume. Associations between intraoperative hyperglycemia and postoperative WMH volume at 3 months follow-up were also assessed by linear regression analyses.RESULTS: Eighteen patients showed intraoperative hyperglycemia (glucose maximum ≥ 150 mg/dL). A preoperative more smooth shape of periventricular and confluent WMH was related to the occurrence of intraoperative hyperglycemia [convexity: OR 33.318 (95 % CI (1.002 - 1107.950); p = 0.050]. Other preoperative cerebrovascular markers were not related to the occurrence of intraoperative hyperglycemia. Intraoperative hyperglycemia showed no relation with pre- to postoperative changes in WMH volume nor with postoperative WMH volume at 3 months follow-up.CONCLUSIONS: We found that a preoperative more smooth shape of periventricular and confluent WMH was related to the occurrence of intraoperative hyperglycemia. These findings may suggest that a similar underlying mechanism leads to a certain pattern of vascular brain abnormalities and an increased risk of hyperglycemia.  相似文献   
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