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1.
中药挥发油质量的稳定性是其发挥临床疗效及确保安全性的重要前提。由于中药挥发油的质量受到入药部位、药材产地、药材采收期、提取工艺、炮制工艺等诸多因素的影响,从而导致挥发油的出油率或所含化学成分出现差异,影响中药挥发油质量的均一性,进而影响挥发油的疗效。因此,如何把控挥发油的质量是中药挥发油发挥作用的关键。分析了药材不同入药部位、不同产地和不同采收期对中药挥发油质量的影响,并对《中国药典》2015年版含有挥发油成分的196味中药按药用部位进行分类,讨论了不同入药部位、产地和采收期对中药挥发油成分的差异性,以期为中药挥发油的开发及中药挥发油质量标准的建立提供参考。 相似文献
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沙苑子本草考证 总被引:1,自引:0,他引:1
沙苑子为我国常用中药,药用历史悠久。通过查阅本草文献,对沙苑子名称、基原、功效、产地及伪品5个方面进行考证,得知其名称演变大致经过"白蒺藜""沙苑蒺藜""沙苑子"3个阶段;历代本草记载沙苑子基原为扁茎黄芪的干燥成熟种子,古今应用品种基本一致;沙苑子补肾固精功效的记载自宋《本草衍义》起逐渐清晰明确;沙苑子道地产区自宋时起为陕西沙苑,明清时期产地逐渐转到陕西潼关、山西等地,建国后以陕西省为主向北扩散,以陕西潼关为佳;沙苑子建国前有马薸子、色微绿伪品及紫云英子等混伪品,建国后有紫云英、猪屎豆、华黄芪和直立黄芪的种子等混伪品。为沙苑子正本清源,并为其进一步深入开发提供参考。 相似文献
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Qiaoqiong Shang 《Journal of community psychology》2020,48(3):849-861
This study aims to examine the extent to which people are socially integrated and the association between social support and depressive symptoms among Chinese adults, with regard to the moderating effect of the rural or urban residence. The author used data from the China health and longitudinal study (CHARLS), a nationally representative longitudinal survey of the population of adults aged over 45 in China. A total of 16,372 participants were included in this study, and the mean age of the sample was 59.7. Three variables were used to measure participants' social support: family size, proximity of support, and social involvement. The Chinese version of 10-item center for epidemiologic studies depression scale was used as a measurement tool for depressive symptoms. The findings demonstrate that small family size, living with a spouse, frequency of contact with children, and a number of social activities have significant effects on depressive symptoms. For all aspects of social support, the influence on depressive symptoms is not significantly different between urban and rural areas. Family support, especially the support of a spouse is crucial to prevent depression. This study also identifies the vital effect of social activity and encourages the government to improve public services, especially in rural areas. 相似文献
5.
Máximo Fernández Patricio Ahumada-Galleguillos Elisa Sentis Gonzalo Marín Jorge Mpodozis 《The Journal of comparative neurology》2020,528(2):321-359
Recent reports have shown that the avian visual dorsal ventricular ridge (DVR) is organized as a trilayered complex, in which the forming layers—the thalamo-recipient entopallium (E), an overlaying nidopallial stripe called intermediate nidopallium (NI), and the dorsally adjacent mesopallium ventrale—appear to be extensively interconnected by topographically organized columns of reciprocal axonal processes running perpendicular to the layers, an arrangement highly reminiscent to that of the sensory cortices of mammals. In the present report, we implemented in vivo anterograde and retrograde tracing techniques aiming to elucidate the organization of the connections of this complex with other pallial areas. Previous studies have shown that the efferent projections of the visual DVR originate mainly from the NI and E, reaching several distinct associative and premotor nidopallial areas. We found that the efferents from the visual DVR originated solely from the NI, and confirmed that the targets of these projections were the pallial areas described by previous studies. We also found novel projections from the NI to the visual hyperpallium, and to the lateral striatum. Moreover, we found that these projections were reciprocal, topographically organized, and originated from different cell populations within the NI. We conclude that the NI constitutes a specialized layer of the visual DVR that form the core of a dense network of highly specific connections between this region and other higher order areas of the avian pallium. Finally, we discuss to what extent these hodological properties resemble those of the mammalian cortical layers II/III. 相似文献
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《"健康中国2030"规划纲要》将普及健康知识作为主要目标之一,健康科普已成为公众关注的重要领域,而新媒体已成为公众获取健康知识的主要平台。该研究根据新媒体环境下用户和信息传播的特点,以健康科普视频为实例,制定并研究健康科普视频的创作模式和传播策略,以期对新媒体环境下健康信息普及、公众健康素养提升提供借鉴。 相似文献
8.
目的 了解黔南州2011—2020年肺外结核流行特征,为制定防控措施提供依据。方法 收集结核病管理信息系统登记的黔南州2011— 2020年肺外结核病例资料,采用描述流行病学方法进行分析。结果 2011—2020年黔南州肺外结核发病9 397例,年均报告发病率为28.12/10万,占全人群结核病的平均比例为19.12%(9 397/49 138),其发病率呈缓慢上升趋势;男性5 037例,占53.60%(5 037/9 397);女性4 360例,占46.40%(4 360/9 397)。男女比例为1.16:1;全年均有病例,主要集中在第一季度和第二季度;黔南州12县(市)肺外结核患者发病数前三位分别是三都县12.60%(1 184/9 397)、罗甸县10.57%(993/9 397)和长顺县10.38%(975/9 397)。按民族分析,肺外结核中病例数前三位分别是苗族25.28%(2 376/9 397)、布依族21.68%(2 037/9 397)和水族15.56%(1 462/9 397);10年间发病农民病例数占总发病数的63.50 %(5 967/9 397);总体发病年龄46~60岁发病数最多。男性16~30岁和46~60岁发病数较多,呈“M”型双波峰形。女性发病数集中在31~60岁呈单波形;肺外结核以结核性淋巴腺炎最多,占全部肺外结核20.77%(1 952/9 397),其次是泌尿生殖系统结核病17.41%(1 636/9 397)和骨关节结核病13.86%(1 302/ 9 397);发现方式以因有症状就诊和转诊为主,占83.25%(7 823/9 397);肺外结核初治成功率96.92%(9 108/9 397),复治成功率73.36%(212/289)。结论 2011—2020年黔南州肺外结核病呈缓慢上升趋势,男性、农民、布依族、年龄46~60岁是肺外结核防治的重点人群。 相似文献
9.
Antje Biesemeier Tatjana Taubitz Sylvie Julien Efdal Yoeruek Ulrich Schraermeyer 《Neurobiology of aging》2014
This work presents a combined light and electron microscopical approach to investigate the initial breakdown of the retinal pigment epithelium (RPE) and choriocapillaris (CC) in age-related macular degeneration (AMD). Perimacular sections of 12 dry and wet AMD eyes (82 ± 15 years) and 7 age-matched controls (75 ± 10 years) without retinal pathology were investigated. Disease progression was classified into 5 stages of retinal degeneration to investigate the concurrent CC breakdown. Special emphasis was laid on transitions where intact CC–RPE–retina complexes went over into highly atrophied areas. AMD sections showed elevated loss of photoreceptors, RPE and CC (p < 0.01), and thickened Bruch's membrane with increased basal laminar and linear deposits compared with controls. Up to 27% of the CC was lost in controls although RPE and retina were still intact. This primary loss of CC further increased with AMD (up to 100%). The data implicate that CC breakdown already occurs during normal aging and precedes degeneration of the RPE and retina with AMD, defining AMD as a vascular disease. Particular attention should be given to the investigation of early AMD stages and transitional stages to the late stage that reveal a possible sequence of degenerative steps with aging and AMD. 相似文献
10.
目的:建立不同产地高乌头药材的HPLC指纹图谱,并测定其中2种主要生物碱成分含量,为高乌头药材质量控制提供参考依据。方法:采用HPLC-DAD技术,以Dikma spursil C18色谱柱(4.6 mm×250 mm,5μm),乙腈-0.05 mol·L~(-1)磷酸二氢钠水溶液为流动相梯度洗脱,建立高乌头药材的指纹图谱并进行含量测定;采用中药指纹图谱相似度评价系统(2012版)对10批样品进行共有峰确认及相似度评价;通过SPSS 21.0统计软件采用主成分分析(PCA)和聚类分析(CA)对HPLC指纹图谱进行模式识别分析。结果:建立了高乌头药材指纹图谱,10批高乌头药材的相似度均0.90;标定共有峰11个,并对其中2主要成分(高乌甲素、冉乌头碱)进行含量测定;聚类分析法(CA)将所有批次高乌头药材共分为4类,反映了10个批次不同地区高乌头药材的质量特征;主成分分析法(PCA)筛选出累计贡献率达到89.748%的4个主成分,得到决定高乌头药材质量5个化学成分。结论:建立的HPLC指纹图谱结合含量测定,PCA,CA方法,可以客观、有效、全面地用于高乌头药材的质量评价。 相似文献