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目的确定乳痈平颗粒处方中大黄素的最佳提取工艺。方法以大黄素提取率和得膏率为考查指标,考查乙醇浓度及其用量和煎煮时间对大黄等药材提取效果的影响。结果最佳工艺为:加70%乙醇(9+7)倍量,热回流(2+2)h。结论该最佳工艺是稳定可行的,可用于工业化生产。 相似文献
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Pablo Vega Fátima Valentín Joaquín Cubiella 《World journal of gastrointestinal oncology》2015,7(12):422-433
Colorectal cancer (CRC) is a major health problem in the Western world. The diagnostic process is a challenge in all health systems for many reasons: There are often no specific symptoms; lower abdominal symptoms are very common and mostly related to non-neoplastic diseases, not CRC; diagnosis of CRC is mainly based on colonoscopy, an invasive procedure; and the resource for diagnosis is usually scarce. Furthermore, the available predictive models for CRC are based on the evaluation of symptoms, and their diagnostic accuracy is limited. Moreover, diagnosis is a complex process involving a sequence of events related to the patient, the initial consulting physician and the health system. Understanding this process is the first step in identifying avoidable factors and reducing the effects of diagnostic delay on the prognosis of CRC. In this article, we describe the predictive value of symptoms for CRC detection. We summarize the available evidence concerning the diagnostic process, as well as the factors implicated in its delay and the methods proposed to reduce it. We describe the different prioritization criteria and predictive models for CRC detection, specifically addressing the two-week wait referral guideline from the National Institute of Clinical Excellence in terms of efficacy, efficiency and diagnostic accuracy. Finally, we collected information on the usefulness of biomarkers, specifically the faecal immunochemical test, as non-invasive diagnostic tests for CRC detection in symptomatic patients. 相似文献
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《Renal failure》2013,35(5):709-717
Objective.?It has become common practice to use a day-case based approach to identify from the population of hypertensive patients those with an identifiable cause. We aimed to prospectively identify 96 consecutive hypertensive patients undergoing an algorithmic investigation protocol based around two day case hospital attendances. Methods.?The overall diagnostic yield and associated costs were recorded and the patients were observed for a mean of 2.5 years with ambulatory blood pressure (BP) monitoring every three months. Results.?A secondary cause of hypertension was identified in 18.1% of patients, three quarters of whom had renovascular disease. There was a fall in blood pressure with time (157/97 vs. 140/85) but this was associated with an increase in the amount of medication required (mean medication score 5.99 vs. 7.65). Improvement in BP occurred irrespective of whether or not a secondary cause was identified. Only 3.2% of patients were cured of their hypertension as a result of enrollment in the protocol. The cost of identifying each case of secondary hypertension was Euro 10, 196. Conclusions.?A comprehensive protocol aimed at identifying secondary hypertension had a low yield, the majority of whom had renovascular disease. In light of recent data illustrating the lack of improvement in BP following dilatation or bypass of atherosclerotic renovascular disease, it is debatable whether searching for it is justifiable. 相似文献
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常用中药紫苏叶和紫苏叶油的基原植物应为PA型紫苏。课题组对全国紫苏资源全面调查后发现,PA型紫苏资源十分紧缺。而PA型栽培紫苏都属株型矮小、叶片轻薄的回回苏变种,单株叶片产量较低。该研究以2份药用PA型紫苏为材料,在5个种植密度(D1,2 500株/亩;D2,5 500株/亩;D3,8 500株/亩;D4,11 500株/亩;D5,14 500株/亩,1亩≈667 m^2)下种植。选取叶型、株型、产量、挥发油含量和挥发油成分构成等17个性状记录和研究。结果表明,随密度增加,叶型、株型变窄、变小,落叶增加,单株叶产量降低,而叶亩产量增加,且达到D4后基本稳定。叶挥发油提取率在种植密度D2~D5较D1高约0.1%,各个密度下紫苏醛相对含量无显著差异。各个密度下紫苏醛相对含量无显著差异。2份PA种质的耐密植特性有较大差异,与其株型的特征有关,尤其收敛型株型更能适应密植环境。为达到高叶亩产量,推荐以D4(株行距15 cm×40 cm)密度下种植;而综合叶产量、叶型、株型,推荐以D2(株行距30 cm×40 cm)密度下种植。落叶节数、二级分枝数,株型可作为PA型紫苏种质耐密性评价的特征,收敛株型可作为紫苏种质高产育种的评价指标。该研究为PA型紫苏适宜种植的密度提供参考,并为进一步研究不同紫苏的耐密植特性奠定基础。 相似文献
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