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目的：考察苍术遗传变异与挥发油变异的关系,揭示苍术挥发油变异的生物学基础。方法：分单株取来源于多个居群的苍术,同株苍术根茎与叶片采用同一编号,根茎用GC—MS分析挥发油变异,叶片采用随机扩增多态性（RAPD）技术分析遗传变异,然后利用方差分析、聚类分析等分析二者的关系。结果：①不论在个体水平还是居群水平,苍术非道地药材与道地药材的差异显著,前者（居群Ⅰ和Ⅱ的亚居群1～5,样品1～36）主要由茅术醇和p-桉叶醇组分;后者（居群Ⅲ的亚居群6、7,样品37—47）主要由苍术酮和苍术素组成,并含有较多茅术醇和p-桉叶醇;②RAPD数据在居群水平的分析显示,苍术居群Ⅱ和Ⅲ聚类后,再与居群Ⅰ聚类。个体水平上,居群Ⅲ的全部11个个体聚为一类,亚居群5的5个个体聚类,其他苍术个体均为按居群或亚居群聚类。结论：不论在居群水平还是个体水平,苍术挥发油变异与遗传变异均呈现出特有的规律性,但二者并不一致,提示除了遗传因子外,环境因子对苍术道地药材的形成具有重要作用。 相似文献
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采用水蒸气蒸馏法分别从甘肃省兰州市的榆中、七里河、西固不同产地百合中提取挥发油.用气相色谱-质谱联用技术（GC-MS）对其挥发油中的化学成分进行分离和结构鉴定,并运用气相色谱峰面积归一法,确定所鉴定出的化合物峰面积相对含量约占挥发油总量.结果显示,不同产地兰州百合挥发油的成分和含量存在一定差异,榆中百合挥发油共鉴定出23种化合物;七里河百合挥发油共鉴定出1 0种化合物;西固百合挥发油共鉴定出54种化合物. 相似文献
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从表型可塑性、生态型到药用植物化学型的研究 总被引：4，自引：0，他引：4
文章回顾与总结了表型可塑性、生态型研究的成果,重点介绍了表型可塑性的表现形式,表型可塑性对环境的适应性．表型可塑性的遗传基础,表型可塑性的生物学意义,以及生态型的产生,以及生态型的概念、生物学本质及划分方法．并在此基础上,介绍了化学型的概念及研究现状。根据生物学的基本定律,表型变异：遗传变异＋环境饰变,系统分析了化学型与表型可塑性和生态型的关系及其形成机制和生物学本质,指出表型可塑性、生态型及化学型形成的机制都是遗传变异与环境饰变的共同作用的结果,区别是前者更关注环境饰变,而后二者则同时关注遗传变异与环境饰变的共同作用。最后,借鉴表型可塑性、生态型的研究成果,提出了化学型的研究策略：首先．认为药用植物化学型的研究中应重视研究样品的全面性和代表性,化学型与其它表观性状的相关性,化学型的地理相关性,化学型与基因型的相关性等问题。然后,针对种内化学成分变异是否呈现明显或较明显间断分别给出了化学型的分类原则,对化学成分变异存在明显或较明显变异的物种,要求其化学型的划分尽量做到与某个有明显变异的表型性状相关,与空间地理环境相关,与物种的遗传分划相关;对于化学成分呈现连续变异的物种,可借鉴农学上的“等级系列划分法”,不把生态型截然分开,而将其看成一个变化系列来考虑。最后,初步提出了化学型的研究思路和方法为：化学成分明显变异的发现一化学成分变异幅度及规律的系统分析→化学型的初步划分→表型相关性、地理相关性及遗传背景分析→化学型划分结果的修正→受控试验→化学型的确定→药效安全性评价。 相似文献
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正达尔文进化学说的主要内容是自然选择,包括:生物的过度繁殖、生存竞争、遗传和变异,以及适者生存。在生存竞争中,具有有利变异的个体,容易在竞争中获胜而生存下去。反之,具有不利变异的个体,则容易在竞争中失败而死亡。但是,进化的观点也强调,能生存下来的个体不一定就是最适者,只有生存下来并留下 相似文献
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不同区域聚集的产业集群显示出创新效率的差异以及创新能力的差异,不同集群应对应不同的创新效率提升路径。以我国创新型产业集群数据为基础,首先使用数据包络分析（DEA）-马姆奎斯特（Malmquist）指数法计算集群创新效率,分为全面型、技术进步型、技术薄弱型、规模经济型4类集群,再使用模糊集定性比较分析法（fsqca）识别出不同情形下影响集群创新效率的7条路径,并分为全面型、环境型、聚集型,得到不同类型集群的创新提升路径。结果表明：（1）北京的创新型产业集群是唯一属于全面型,福建、贵州、重庆、湖北的创新型产业集群属于技术进步型,内蒙古、吉林、云南的创新型产业集群属于技术薄弱型,江苏、浙江、四川、天津的创新型产业集群属于规模经济型;（2）全面型路径适用全面型和技术进步型集群,技术薄弱型集群适合环境型路径,聚集型路径适用于技术进步型和规模经济型集群,但同一类型产业集群在不同地区可以对应不同路径达到提高创新效率的效果;（3）集群数量、产业联盟数和当年发明专利授权数量是影响创新型产业集群创新效率的主要指标。 相似文献
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海上溢油的环境化学行为分析 总被引：1，自引：0，他引：1
石油是一种复杂的多组分均质混合物,其主要组分为烃类(烷烃、环烷烃和芳香烃),其次是数量不多但很有意义的非烃组分(如含氧化合物、含硫化合物、含氮化合物、胶质和沥青质等).本文对海上溢油的环境化学行为进行了分析和探讨. 相似文献
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S. P. Kulkarni C. R. Mallikarjuna D. S. Jayaprakash Murthy 《Indian journal of clinical biochemistry : IJCB》2006,21(1):185-188
Background Sialic acid (SA) is a nine carbon sugar derived from mannosamine and pyruvate. High levels of sialic acid and aspartate transaminase
(AST) levels in cerebrospinal fluid have been described in pyogenic meningitis (PM) compared to tubercular meningitis (TBM).
Objectives To evaluate the levels of CSF free SA in PM and TBM and to assess the correlation between CSF free SA and CSF glucose or total
protein levels.
Patients and Methods A total of 122 subjects were studied and divided into children and adults. Further, these have been subdivided into controls,
PM and TBM. CSF free SA was estimated by thiobarbituric acid assay of Warren and AST by Reitmann and Frankel method.
Results CSF free SA and AST levels in children and adults were significantly high in PM (p<0.001) as compared to TBM and controls.
Conclusion A very high CSF free SA and AST were found to be characteristic of PM, making them useful parameters to differentiate PM from
TBM. 相似文献
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This paper deals with intercultural aspects of privacy, particularly with regard to important differences between Japanese
and the Western views. This paper is based on our discussions with Rafael Capurro – a dialogue now represented by two separate
but closely interrelated articles. The companion paper is broadly focused on the cultural and historical backgrounds of the
concepts of privacy and individualism in “Western” worlds; our main theme focuses on different concepts of privacy in Japan
and their sources in related aspects of Japanese culture. The interrelationship between our two papers is apparent in our
taking up identical or similar topics in each paper. Reading our two papers in conjunction with each other will bring about
deeper and broader insights into the diverse values and worldviews of Japan and Western cultures that underlie concepts of
privacy that at a surface level appear to be similar 相似文献
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【目的】 分析《中华医学杂志英文版》(Chinese Medical Journal,CMJ)与国外三大医学期刊《新英格兰医学杂志》《柳叶刀》《美国医学会杂志》通讯类文章的差异,为优化国内医学期刊通讯类栏目提供参考。【方法】 利用Web of Science数据库和《期刊引证报告》,比较2015—2016年CMJ与国外三大医学期刊通讯类文章的载文情况,分析2017年排名前10位高被引文章的特点。【结果】 CMJ通讯类文章刊载量、比例、被引频次和引用率均明显偏低;同时,对学科研究热点追踪程度低,从而导致被关注程度较低。【结论】 国内医学期刊对通讯类文章重视程度不高,所发表的通讯类文章影响力较低。应重视通讯类栏目建设,及时把握相关学科领域的研究前沿和社会热点,刊发高影响力通讯类文章。 相似文献
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Aqueous root extract ofAchyranthes aspera was incorporated in the experimental diet ofLabeo rohita (rohu). Control diet was prepared without root extract. Feeding of fishes with experimental diet has significantly (p<0.05)
enhanced the serum anti-proteases level than fishes fed with control diet. 相似文献
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P Renuka Devi S Krishna Kumari C Kokilavani 《Indian journal of clinical biochemistry : IJCB》2007,22(1):143-147
The effect of the oral administration ofVitex negundo leaf extract on the levels of enzymic and non-enzymic antioxidants were studied in the adjuvant induced arthritic (AIA) rats
The levels of antioxidant enzymes such as SOD, CAT, GPx, G6PD, GSH and Vit-C were estimated in various groups of the experimental
rats. It was observed that the antioxidant enzyme levels in the AIA were significantly low when compared to normal rats. A
significant decrease in enzymic antioxidant—SOD, CAT, GPx, G6PD and non-enzymic antioxidant—GSH, Vit-C were observed in the
liver of AIA rats compared to the normal rats. These results suggest that the leaf extract ofVitex negundo possesses antioxidant activity. 相似文献
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This paper deals with intercultural aspects of privacy, particularly with regard to differences between Japanese and Western
conceptions. It starts with a reconstruction of the genealogy of Western subjectivity and human dignity as the basic assumptions
underlying Western views on privacy. An analysis of the Western concept of informational privacy is presented. The Japanese
topic of ‘‘denial of self” (Musi) as well as the concepts of Seken, Shakai and Ikai (as analyzed by the authors of the companion piece on privacy in Japan) give rise to intercultural comparisons. The paper
addresses the question of privacy in cyberspace and mass media. Finally the question of freedom of speech is related to the
Japanese concepts of Ohyake and Watakusi. 相似文献
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R. Alli B. Bhunia G. P. Chhotray M. V. R. Reddy B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2003,18(1):61-64
Sera samples of 7 microscopic haematuria cases collected before and after treatment with Diethylcarbamazine citrate, (DEC),
9 microfilaraemic cases and 19 endemic normal individuals were analysed for filarial antigen and IgG antibody levels. Filarial
antigen was detected in 5 of the 7 microscopic haematuria cases, of which 3 turned negative for antigen after treatment with
DEC. While none of the 7 haematuria cases were positive for filarial IgG antibodies, before the DEC treatment, all of them
turned positive after DEC treatment. The sensitivity and specificity values(to detect mf +ve cases) were 89% and 90% respectively
for the detection of filarial antigen and 78% and 95% respectively for the detection of filarial IgG antibodies. 相似文献
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基于MODIS数据的泰国林地资源提取 总被引：1，自引：1，他引：0
遥感技术的发展为我们对世界资源的研究提供了新的手段,克服了世界资源研究过程中数据缺乏的困难。泰国曾经是林地资源丰富的国家,尤其是热带林地资源,但是近几十年来林地面积在不断减少,带来了一系列生态问题。选用MOD09Q1的1、2波段,MOD09A1的第6波段以及MOD11A2数据产品提取了泰国林地分布情况。由于泰国地处热带地区云雾噪音为林地的提取造成了很大的不确定性,为了有效去除云雾噪音影响,结合NDVI、NDSI、LST多参数在林地提取中的优势对泰国林地进行提取。采用泰国2003年统计年鉴提供的分省林地面积以及2003年p131r47和p131r48共2景ETM影像进行了精度验证。结果表明,利用多参数综合分类方法对林地提取精度较高,通过与2003年统计年鉴数据进行回归分析发现二者存在明显的线性关系,决定系数达到0.9264。 相似文献
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【目的】 探讨我国医学期刊在富媒体数字内容开发方面的有效路径。【方法】 以《新英格兰医学杂志》《柳叶刀》《美国医学会杂志》《英国医学期刊》四大医学期刊网站富媒体数字内容为主要调研对象,结合国内医学期刊现状以及笔者所在编辑部实践情况,分析探讨我国医学期刊富媒体数字内容开发现状。【结果】 随着数字化出版革命的不断演进,富媒体内容已经成为四大医学期刊数字内容增值服务的重要部分,具有如下特点：均较早地引入专家视频、音频访谈内容;越来越多的文章以富媒体形态出版;对期刊学术资源进行二次加工,推出多种交互式产品;出现视频形态的“文章”;信息图得到广泛应用;部分资源通过付费订阅等方式开辟新的营收途径。国内医学期刊数字化发展还处于初级阶段,富媒体内容开发能力薄弱,应当从加强集约化经营、重视专门人才的引进以及培养、充分发掘自身特色资源等方向入手,增强富媒体内容的开发能力。【结论】 国内医学期刊应当学习借鉴四大医学期刊在富媒体内容开发方面的先进经验,结合实际情况和自身特色,提高富媒体内容开发能力,更好地促进学术影响力的提升,创造更大的社会效益和经济效益。 相似文献
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Poonam Gautam Taruna Madan W. N. Gade P. Usha Sarma 《Indian journal of clinical biochemistry : IJCB》2006,21(2):12-19
Allergenic/antigenic proteins are known to induce Type I and Type III hypersensitivity reactions leading to allergic bronchopulmonary
aspergillosis (ABPA) in immunocompetent host. The common structural features or intrinsic properties of the allergens/antigens
leading to allergenicity in a host are not well understood. In the current report, comparative analysis of proteins on two
dimensional gel electrophoresis (2D-3) and specific IgE immunoblots ofA. fumigatus secretory proteins (1st, 2nd and 3rd week culture filtrate proteins) was carried out. We observed a total of 159 proteins in 1st, 2nd and 3rd week culture filtrates ofA. fumigatus. Specific IgE immunoreactivity was observed in 75 proteins with different intensity. Third week culture filtrate showed maximum
number of proteins, 142, and specific IgE immunoreactive proteins, 65. MALDI-TOF analysis resulted in putative identification
of two allergens as hypothetical protein YBL057c fromSaccharomyces cereviseae and unnamed protein product fromDebaryomyces hansenii (similar to IPF14568 ofCandida albicans). Identification of a repertoire of specific IgE immunoreactive proteins will facilitate the studies on structure-function
relationship of these proteins relevant for diagnosis and pathogenesis. 相似文献