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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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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   
999.
Tongue cancer involving the anterior tongue often presents at an early stage. The aetiology is strongly associated with smoking and alcohol abuse similar to other squamous cell carcinomas (SCC) of the head and neck (HN). Surgery and radiotherapy, either alone or together, offer the prospect of cure in the majority of patients. However, there remains a group of younger patients less than 40 years old for whom outcome is often poor. Presented here is the case of a 24-year-old woman who developed SCC of the anterior tongue. Despite treatment, loco-regional relapse occurred resulting in death. The literature identifies a distinct subgroup of younger patients who develop HN SCC, particularly of the oral cavity. The aetiology remains unclear. Recent studies have looked at the prognostic significance of various new non-clinico-pathological markers in HN SCC (including p53 tumour suppressor gene, cyclin D1 protein, Ki 67 antigen and tumour angiogenesis). The majority of these studies, as expected, have involved the typical HN patient (male, aged > 60 years old). However, the relevance of these studies is of likely importance to all patients diagnosed with HN SCC. The recent use of these non-clinical-pathological markers in HN SCC, including reference to such studies in younger patients, is discussed. The English literature during the past 30 years is reviewed with reference to the diagnosis of tongue SCC in younger patients.  相似文献   
1000.
Several studies have shown that the human papilloma virus (HPV) test is a more sensitive and objective primary cervical cancer screening tool than cytology. Therefore, conversion of cytology into HPV screening (as is planned in The Netherlands and some other European regions) will result in a better protection against cervical cancer and high-grade precursor lesions. Moreover, offering self-sampling for HPV testing will increase screening attendance by re-attracting former non-attendees. However, triage of HPV positive women is necessary because the specificity of HPV testing is 2–4% lower than of cytology. Several triage strategies have been evaluated, of which two, with cytology testing included, are feasible and were recently recommended. As an alternative for cytology triage, objective, non-morphological disease markers are upcoming and so far have shown promising results. Finally, HPV testing can also contribute to a more efficient monitoring of women treated for high-grade cervical precursor lesions, permitting fewer follow-up visits.  相似文献   
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