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1.
为研究不同地区黄精差异性和相似性,运用化学计量学手段对不同地区黄精氨基酸含量进行特征分析和聚类分析。通过主成分分析对不同地区黄精进行综合排名,验证了氨基酸含量与黄精药用、保健价值的相关性;运用聚类分析对不同地区黄精进行聚类,了解不同地区黄精之间的相似性。为黄精的鉴定和综合开发利用提供理论基础和科学依据。  相似文献   

2.
宁夏黄精中黄精多糖的提了以,分离和测定   总被引:3,自引:0,他引:3  
应用分光光度法对宁夏不同产地黄精中的黄精多糖进行了测定,为宁夏黄精药 的质量评价提供了方法依据科学依据。  相似文献   

3.
宁夏黄精中黄精多糖的提取、分离和测定   总被引:6,自引:0,他引:6  
应用分光光度法对宁夏不同产地黄精中的黄精多糖进行了测定,为宁夏黄精药材的质量评价提供了方法依据和科学依据  相似文献   

4.
一、引言 九华黄精为多年生草本植物。属药食兼用的大宗药材。《中国药典》规定黄精是以百合科黄精属植物黄精、滇黄精、多花黄精的干燥根茎人药。九华黄精在九华山地区生长范围较广,阴湿山坡和沟谷处较常见。九华山地区的黄精品种为多花黄精,云南、贵州、浙江、山东也有此品种分布,但药材质量都不如九华山地区。为突出其地方特色,取名为九华黄精。  相似文献   

5.
从衰老的定义和衰老学说中的自由基学说、端粒学说、线粒体DNA损伤学说、神经内分泌学说角度出发,综述了黄精多糖在清除自由基、增强端粒酶活性、改善线粒体能量代谢、改善神经内分泌功能等方面的作用机理,总结了黄精多糖的提取方法以及在健康食品和日常膳食的研发和应用进展,展望了黄精及黄精多糖的未来研发方向,指出黄精必将成为人们健康生活不可或缺的一部分。  相似文献   

6.
中药黄精的研究和开发利用途径   总被引:14,自引:0,他引:14  
黄精是传统医学上长期使用的具有滋补强身、延缓衰老作用的食疗中药。就国内对黄精的药理作用和化学成分方面的研究进行了探讨,指出了黄精资源开发利用的主要途径。  相似文献   

7.
黄精属于百合科,黄精属的植物,其块根内含有大量的淀粉、糖类、沾液质、维生素及多种微量元素,具有滋补阴血、滋养脾胃及润肺的功能,自古被中医、藏医所利用。西藏是我国黄精资源的主要产区之一,据研究区内共有7种黄精。即:轮叶黄精Polyonatum Verticillatum(L)ALL. 点花黄精Polygonatum Punctatum Royle ex Kunth. 独花黄精Polygonatum hookvi Baker. 对叶黄精Polygonatum oppositifolium(Wall)Royle. 三脉黄精Polygonatum griffithii Baker. 卷叶黄精Pobygonatum cirrhifolium(wall)Royle. 棒丝黄精Polygonatum cathcartii Baker等7种,广泛分布于西藏的东部、东南部地区。 近年来,黄精不仅作为药用,还研制出了饮料,食品添加剂,美容剂等系列产品,西藏黄精属的种类多、分布广、储量大、具有一定的开发前景。  相似文献   

8.
付玉平  钟玉贵 《汉中科技》2013,(4):21-21,12
黄精药食两用,市场前景好,野生资源面临枯竭。利用山区林地和退耕还林地种植黄精具有显著地经济、生态和社会效益。本文在实践的基础上,从选地整地、种植方法、管理措施、病虫害防治及采收加工几个方面总结了黄精生态种植技术。  相似文献   

9.
黄精属几个种的染色体研究   总被引:1,自引:0,他引:1       下载免费PDF全文
本文研究江苏,浙江,安徽三省黄精属(Polygonatum)4个种的核型,囊丝黄精(P.cyrtonema)2n=18,20,n=9,10;核型属不对称型;长梗黄精(P.filipes)2n=18,n=9,属不对称型;湖北黄精(P.zanlanscianense)2n=28,30,32,n=14,15,16,属不对称型;黄精(P.sibiricum)2n=24,n=12,属不对称型。黄精(P.sibirlcum)的2n数与国外报导的2n数不同,属新记录。囊丝黄精,长梗黄精,湖北黄精的2n数属初次记载。  相似文献   

10.
对黄精组培进展进行简要概况,对影响组培的主要因素进行总结,详细论述了外植体污染控制、植物生长调节剂组合以及组培苗移栽驯化的常见的问题及相关建议,提出黄精组培的工作思考,可为黄精组培快繁技术和产业化发展提供参考.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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