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1.
刘蕤  陈紫雯  华桂丰  王立强  萨翼  刘昶 《中草药》2020,51(18):4829-4836
目的建立保健食品原料评价体系(Functional Food Crude Materials Evaluation System,FUFMES),为保健食品原料目录排名提供科学依据与技术保障。方法首先,利用文献调研和多轮专家访谈方法筛选FUFMES的指标并确定其层级关系;第二,使用层次分析法(Analytic Hierarchy Process,AHP)计算指标权重,具体方法是依据专家打分构建判断矩阵,利用R语言进行一致性检验与最大特征根检验,得出各级指标权重;第三,使用极值法计算原料的单个指标值;第四,利用线性加权综合法得到每种原料的评价指数并据此进行排名;最后,将获得的分析结果与专家评价结果进行比较。结果 FUFMES包括6个一级指标、39个二级指标、11个三级指标。利用FUFMES对9种保健食品原料进行评价,获得的评价指数依次是:西洋参(0.49)、人参(0.48)、银杏叶(0.21)、灵芝孢子粉(0.08)、鱼油(0.06)、螺旋藻(0.03)、辅酶Q10(0.02)、褪黑素(0.01)、大蒜油(-0.03)。基于该评价指数的排名结果与专家评价结果显示了较高一致性。结论构建了科学、完整的FUFMES,FUFMES将成为保健食品原料目录评价与排名的有力工具,为推进保健食品原料备案制提供科学依据与技术保障。  相似文献   
2.
参麦注射液是由红参、麦冬制得的中药注射剂,具有益气固脱、养阴生津、生脉的功效,临床上用于治疗气阴两虚型之休克、冠心病、病毒性心肌炎、慢性肺心病、粒细胞减少症。主要围绕与产品质量紧密相关的生产工艺、药材质量、辅料3个方面进行总结,为优化该产品的生产工艺、提高产品质量提供参考。  相似文献   
3.
《Dental materials》2019,35(12):1805-1812
ObjectiveThe aim of this study was to investigate the three-body wear of different additively manufactured temporary materials, one temporary PMMA material for CAD/CAM milling and one resin-based composite for direct restorations as a control group by using an ACTA machine.MethodsSpecimens (n = 8) of the 3D printing materials 3Delta temp, NextDent C&B, Freeprint temp were additively manufactured by DLP 3D printer. Postprocessing was carried out according to the manufacturer's specifications. Telio CAD were cut out of blocks, Tetric EvoCeram was applied directly and light cured. Three-body wear was simulated with an ACTA machine. Data were statistically analysed (ANOVA, post hoc test: Tukey, p < 0.05). The worn surfaces of the specimens were examined with a FE-SEM.ResultsThe average mean wear was 50 ± 15 μm for Tetric EvoCeram < 62 ± 4 μm for 3Delta temp < 236 ± 31 μm for Telio CAD < 255 ± 13 μm for NextDent C&B < 257 ± 24 μm for Freeprint temp. After 200,000 cycles, the wear and wear rates for Tetric EvoCeram and 3Delta temp were significantly lower than those for the other materials. SEM revealed that 3Delta temp has a higher filler proportion than the other 3D printing materials but less than Tetric EvoCeram.SignificanceThe filler content influences the wear behaviour of additively manufactured materials as well as dental restorative composite materials. While most 3D printing materials have a low inorganic filler load, which qualifies the materials for temporary use only, one 3D printing material has an optimized composition that would qualify the material for longer clinical service time if wear is considered as the outcome variable.  相似文献   
4.
Mud nests built by swallows (Hirundinidae) and phoebes (Sayornis) are stable granular piles attached to cliffs, walls, or ceilings. Although these birds have been observed to mix saliva with incohesive mud granules, how such biopolymer solutions provide the nest with sufficient strength to support the weight of the residents as well as its own remains elusive. Here, we elucidate the mechanism of strong granular cohesion by the viscoelastic paste of bird saliva through a combination of theoretical analysis and experimental measurements in both natural and artificial nests. Our mathematical model considering the mechanics of mud nest construction allows us to explain the biological observation that all mud-nesting bird species should be lightweight.

Bird nests come in a variety of forms made from diverse building materials (1, 2). Each type of bird nest is subjected to mechanical constraints imposed by material characteristics. To overcome these constraints, birds have devised brilliant architectural technologies, which provide inspiration for a novel materials processing scheme and help us to better understand animal behavior.For instance, some birds including storks (Cicioniidae) and eagles (Accipitidae) build nests by piling up hard filamentary materials such as twigs, harnessing their friction as the cohesion mechanism (3). Weaverbirds (Ploceidae) weave soft filamentary materials such as grass and fine leaves into a woven nest tied to a tree branch. Some bird species use their own saliva in nest building, which Darwin considered an example of natural selection (4). An extreme case is the Edible-nest Swiftlets, which build their nest purely of self-secreted saliva so that it can be attached to cliff walls and cave ceilings where the above twig piles and tied leaves are not allowed (5).Swallows (Hirundinidae), phoebes (Sayornis), and other mud nesters have developed a unique building material, a mixture of mud and their own saliva, in contrast to those made of purely collected or self-secreted materials (6) (Fig. 1). During construction, mud nesters repeatedly pile a beakful of wet mud on the nest, and liquid bridges are formed in the nest due to evaporation. While building a nest usually takes several weeks, a transition from wet to dry structures can occur within a few hours. Hence, the capillary forces of liquid bridges temporarily provide cohesion such as those in sandcastles. However, unlike sandcastles, dehydrated saliva comes into play for permanent cohesion after complete evaporation (SI Appendix, Supplementary Note 1).Open in a separate windowFig. 1.A nest of the barn swallow (H. rustica). (A) Photograph of a barn swallow nest, taken from under the ceiling of a house in Suwon-si, Gyunggi-do, South Korea (37°16′13.5″N 126°59′01.0″E). (B) SEM image of the nest surface. (C) Chemical composition analysis of the surface shown in B by EDS. The red area indicates a region containing mostly carbon atoms, which may originate from bird saliva. The green area indicates a region containing mostly the silicon atoms of clay particles.Mud itself cannot confer sufficient cohesion and adhesion in mud nests. The ability of mud nests to bear tensile loads originates from the gluing agent in the bird''s saliva, which permeates into granules as a liquid and binds them as a solid after solvent evaporation (68) (SI Appendix, Supplementary Note 2). The gluing agent is called mucin, a family of large glycoproteins that are ubiquitous in animal organs and form a mucus gel with versatile functionality (9). Fig. 1B shows the scanning electron microscopy (SEM) image of a barn swallow’s mud nest consisting of platelet clay particles and larger grains. Energy-dispersive spectroscopy (EDS) mapping image of Fig. 1C clearly shows regions corresponding to organic material which is presumed to be from bird’s saliva.Of particular interest and worth biophysical investigation are the tensile strength of the mud nest with hardened saliva, design principles associated with the saliva-originated strength, and the resulting effects on the evolution of these mud-nesting birds. Principles behind cohesion in granular materials, such as wet sands (10), cemented powder aggregates (11), construction materials (12), and pharmaceutical tablets (13), have been studied to date, exploring the stress transmission, elasticity, and failure (1418), and the formation of solidified bridges (1921). However, little attention has been paid to the cohesion effects of self-secreted polymer materials upon evaporation and the biologically constructed granular architecture like birds’ mud nests. Here we devised experimental techniques to measure the strength of the relatively small and fragile nest specimens in order to mechanically characterize birds’ mud nests. We elucidate how solutes from bird saliva generate solid bridges that give rise to macroscopic tensile strength, which has long awaited physicochemical explanation since its first observation (4). To characterize the design principle of bird''s mud nests, we investigated natural and three-dimensional (3D)-printed artificial nests with various tools for visualization and mechanical testing. Along with the experimental studies, we theoretically investigated the effects of biopolymer concentration on nest strength. This combination of theory and experiment suggests that there is a size limit for mud-nesting birds, which is supported by biological data.  相似文献   
5.
孙文杰  奉典旭  黄品贤  宋花玲 《中草药》2019,50(11):2743-2749
通过对"全国中药资源普查及种质共享数据专题服务——中药材产业扶贫"数据资料及"康美中药网——中药全产业链服务平台"各贫困地区中药材资源信息的整理分析,构建中国贫困地区的中药材种植面积、产值等数据库,利用ArcGIS软件绘制贫困地区中药材种植情况空间分布图,从中发掘和总结当前我国中药材产业扶贫的空间格局特征和发展规律。在此基础上,通过参考"中国减贫数据库"及"国务院扶贫开发领导小组办公室"的相关报告,综合分析影响中药材产业扶贫成效的主要因素,并提出相应的建议,以期对贫困地区开展中药材产业扶贫工作提供参考。  相似文献   
6.
张恬  郭宇博  李军德 《中草药》2019,50(18):4490-4494
药用动物资源是中药资源的重要组成部分,是中医药发展的重要战略储备资源,在野生药用动物资源日渐匮乏的今天,大力开展药用动物人工养殖才能确保我国中医药产业的可持续发展。然而《中国药典》2015年版一部收载的106种药用动物中仅有22种(除家畜家禽外)有现行选育、养殖相关标准,共211项,其中除国家标准7项、行业标准(农业、水产)11项外均为地方标准,远远落后于同类型农业标准化程度,无法实现动物药材规范化生产。亟需对常见动物药材蟾酥、水蛭、全蝎等建立包括基础标准、产品标准、工艺过程标准、安全标准、环境保护标准、管理标准、工作标准在内的动物药材生产及产地加工技术标准体系,补充产业空白,从源头把控动物药材、动物类中药饮片及含有动物性成分中药产品质量。  相似文献   
7.
With the rapid development of computer‐aided design/computer‐aided manufacturing (CAD /CAM ) systems, the application of zirconia in removable partial dentures is expected to expand. Clasps composed of zirconia should improve esthetics without inducing the risk of metal allergy. The aim of this study was to examine the fatigue resistance of yttria‐stabilized tetragonal zirconia polycrystal (Y‐TZP) clasps for removable partial dentures. Yttria‐stabilized tetragonal zirconia polycrystal and cobalt‐chromium (Co‐Cr) alloy were prepared using CAD /CAM systems. Specimens were either of the semicircular type or of the flat type, with cross‐sectional areas of taper ratios of 0.50, 0.75, and 1.00. All specimens were tested using the cantilever test and the constant displacement fatigue test, and data were analyzed using ANOVA . During the cantilever test, the maximum displacement prior to fracture was greater than the required undercut, and the semicircular‐type specimen exhibited a higher fracture load than the flat type. None of the specimens displayed permanent deformation and showed almost the same degree of deformation after fatigue testing. A lower taper ratio was associated with lower average load values and greater displacement. Within the limitations of this study, it was possible to conclude that Y‐TZP provides the required undercut and adequate retentive force for removable partial denture clasps. Additionally, Y‐TZP and Co‐Cr alloy had almost the same degree of deformation even after the simulated lifespan of removable partial dentures.  相似文献   
8.
Optical fluorescence imaging methods have a range of forensic applications. The VistaCam system (Dürr Dental) is an existing intra-oral fluorescence camera, which was designed to aid detection of dental caries using 405 nm wavelength light generated by light emitting diodes (LEDs). This study assessed whether this fluorescence imaging device could also be used to recognize dental restorative materials, which is essential for accurate dental charting of deceased persons who are unidentified. The effect of body fluids (saliva and blood) on performance was also assessed. The VistaCam was used on the bench to assess 55 extracted human teeth with restorations, and samples of restorative materials. Readings were first taken in the moist state and then after the application of human saliva or venous blood. Fluorescence scores were compared using one-way ANOVA. Human enamel gave lower fluorescence than restorations. Different tooth-coloured restorative materials gave similar strong fluorescence scores, without statistically significant differences between them. Fluorescence scores were not affected by the presence of ambient fluids (saliva or blood). Using violet 405 nm light to elicit fluorescence may aid in the recognition of dental restorative materials.  相似文献   
9.
目的: 对海洋生物医用材料在医疗领域的应用情况和海洋生物材料来源医疗器械的安全性评价趋势进行分析,为推进该材料的临床转化提供参考。方法: 归纳海洋生物医用材料的分类和应用,介绍该材料的安全性评价的程序要点,探讨其安全性评价中面临的挑战。结果与结论: 常用的海洋生物医用材料主要为多糖和蛋白质,在创伤修复和组织工程领域应用广泛。海洋生物医用材料具有生物活性和良好的生物相容性,对此类材料的安全性评价应根据材料特性和预期用途,科学制定评价程序和选择检验方法。  相似文献   
10.
何首乌作为药物,始载于宋代《开宝本草》,为传统的补益类药材。近年来,何首乌的肝毒性引起了国内外学者的高度关注。该文对历代本草著作中的何首乌药图进行了考证,并对影响何首乌的品质及毒性因素进行了本草学考察。历代本草中收载的何首乌图基本上均为蓼科植物何首乌Polygonum multiflorum,仅《太乙仙制本草药性大全》和《圖解本草》中的附图可能分别为蓼科植物翼蓼Pteroxygonum giraldii和薯蓣科植物黄独Dioscorea bulbifera。历代本草著作中何首乌图与萝藦科鹅绒藤属植物相差甚远。唐代《何首乌传》中已经注意到何首乌块根中的异常维管束,该特征被历代本草所沿承,这也是推断其基原为蓼科植物何首乌的证据之一。历代本草中对异常维管束性状的描述逐渐形成了"云锦花纹"这一术语,并认为"五瓣者良"。此外,古代医药学家已经注意到不同性状的何首乌存在毒性有无之别,即"体润而嫩大者佳""老硬多筋,服之塞血"。该文梳理了历代本草中何首乌种质及其"辨状论质"观,为开展何首乌质量评价研究提供了本草学依据。  相似文献   
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