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91.
92.
Mechanism of the antitumor action of the 4-O-methylglucuronoxylan obtained from beech wood (Fagus clenata Blume) was studied and compared with that of other hemicelluloses. It was revealed that 4-O-methylglucuronoxylan did not show any direct cytocidal effect on tumor cells. Hemagglutinating antibody in mice was markedly enhanced by administration with 4-O-methylglucuronoxylan. Furthermore, treatment with the polysaccharide succeeded to prevent the suppression of hemagglutinating antibody production accompanied with the tumor development. Incorporation of 3H-thymidine into spleen cells at the 4 days after immunization with human red blood cell was increased by the pretreatment of 4-O-methylglucuronoxylan. On the other hand, metabolic process of 4-O-methyglucuronoxylan was followed by the measurement of the radioactivity in plasma, kidney, spleen and liver after intraperitoneal injection with 3H-4-O-methylglucuronoxylan. The polysaccharide seemed to be incorporated into reticuloendotherial systems. An administration of 4-O-methylglucuronoxylan by intraperitoneal injection markedly suppressed both the Ehrlich carcinoma and Sarcoma-180 (S–180) cells in peritoneal cavity of the mice. 相似文献
93.
为探讨第四纪冰期气候波动对青藏高原多年生草本植物青海当归地理分布格局形成的影响,检测了青海当归16个居群147个个体的核糖体内转录间隔区(ITS)的序列变异,共发现了7个单倍型.结果表明除松潘居群外其余15个居群都拥有单倍型H1,青藏高原边缘的居群拥有6种ITS单倍型,其中5种为私有单倍型.谱系关系分析显示单倍型H1为较古老的单倍型,AMOVA分析表明,居群间的变异占了总变异量的67%,居群遗传分化显著,并且存在较明显的谱系地理结构(NST>GST,P<0.05).我们认为青海当归在第四纪冰期最大一次冰期来临时退缩到青藏高原边缘的避难所,冰期后在扩张过程中经历了奠基者效应形成了如今的分布格局. 相似文献
94.
当归叶片光合参数日变化及其与环境因子的关系 总被引:8,自引:2,他引:6
在当归根茎膨大期,利用CI-310便携式光合仪,田间活体测定了当归的净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)等光合生理生态因子,以及光合有效辐射(PAR)、田间CO2浓度(Ca)、相对湿度(RH)、大气温度(Ta)、叶温(TL)等环境因子的日变化。结果表明,当归Pn日变化曲线为"双峰"型,最高峰出现在10:00左右,次高峰出现在16:00左右,午间有明显的"午休"现象,气孔因素是导致其"午休"的主要原因。Tr、Gs和Ci的日变化曲线均为"双峰"型,最高峰出现在10:00,次高峰出现在17:00。当归叶片净光合速率随环境因子日变化最优逐步多元回归方程为yPn=14.3108 0.0076xPAR-0.5271xTL(R2=0.6601,P<0.05),TL和PAR是对光合速率直接影响最大的生态因子,而Ca、RH和Ta主要是通过TL而间接影响光合速率的变化。 相似文献
95.
中国独活属和当归属系统演化及区系地理的温带性 总被引:1,自引:0,他引:1
中国复杂的地质地貌和古老的地史,尤其在横断山区和四川地区,是伞形科独活属及其近邻属的演化和分化中心,区系古老且温带性质明显.从核型和花粉方面分析,独活属和当归属的系统演化表现出比较密切的亲缘关系. 相似文献
97.
The anti-staphylococcal activity of Angelica dahurica (Bai Zhi) 总被引:6,自引:0,他引:6
Bioassay-guided fractionation of a hexane extract prepared from the roots of the Chinese drug Angelica dahurica (Bai Zhi) led to the isolation of the polyacetylenic natural product falcarindiol (1). The absolute stereochemistry of this compound was confirmed by careful 1H NMR analysis of its (R)- and (S)-Mosher ester derivatives as the 3(R), 8(S) isomer. Activity was tracked using a Mycobacterium fortuitum screening assay and the purified product was evaluated against multidrug-resistant and methicillin-resistant strains of Staphylococcus aureus (MRSA). The minimum inhibitory concentrations (MIC) of this metabolite ranged from 8 to 32 microg/ml highlighting the potential of the acetylene natural product class as antibiotic-lead compounds. These MIC values compare favourably with some of the newest agents in development for the treatment of MRSA infection and indicate that further evaluation of the antibiotic activity of acetylenes is warranted. 相似文献
98.
Satish?Manohar?Nalawade Hsin-Sheng?TsayEmail author 《In vitro cellular & developmental biology. Plant》2004,40(2):143-154
Summary Medicinal plants are valuable sources of medicinal and many other pharmaceutical products. The conventional propagation method
is the principal means of propagation and takes a long time for multiplication because of a low rate of fruit set, and/or
poor germination and also sometimes clonal uniformity is not maintained through seeds. The plants used in the phyto-pharmaceutical
preparations are obtained mainly from the natural growing areas. With the increase in the demand for the erude drugs, the
plants are being overexploited, threatening the survival of many rate species. Also, many medicinal plant species are disappearing
at an alarming rate due to rapid agricultural and urban development, uncontrolled deforestation, and indiscriminate collection.
Advanced biotechnological methods of culturing plant cells and tissues should provide new means for conserving and rapidly
propagating valuable, rare, and endangered medicinal plants. The purpose of the present review is to focus the application
of tissue culture technology for in vitro propagation via somatic embryogenesis and organogenesis and the cell suspension culture with suitable examples reported earlier.
An overview of tissue culture studies on important Chinese medicinal plants and related species is presented. 相似文献
99.
Ji-Suk?Cho Ji-Yeon?Kim Ik-Hwan?Kim Dong-Il?KimEmail author 《Biotechnology and Bioprocess Engineering》2003,8(2):158-161
Root cultures ofAngelica gigas Nakai were found to be sensitive to elicitation by polysaccharide elicitors, such as methyl-β-cyclodextrin, glucan, carboxymethyl-β-chitin,
chitosan, yeast extract and pectin. For the production of decursinol angelate, carboxymethyl-β-chitin and glucan were found
to be the most efficient elicitors. The enhanced accumulation of decursinol angelate was proportional to the increase of the
phenylalanine ammonia-lyase (PAL) activity after the treatment with most of the elicitors. However, carboxymethyl-β-chitin
treatment did not stimulate the PAL activity, despite the 1.6-fold increase in the decursinol angelate production. 相似文献
100.
The pathogenic potential and reproduction fitness of Meloidogyne hapla on three species of medicinal plants, Angelica koreana, Peucedanum japonicum and Astragalus membranaceus was determined in potted soil under greenhouse conditions. Three weeks old seedlings were inoculated with population density (Pi) of 1000; 2000; 3000; 4000; 5000 and 10000 juveniles (J2)/kg soil. A significant damage was observed in shoot and root length, weight and root‐diameter of these plants by all Pi levels at 90‐day postinoculation. Damage increased with increase in Pi up to 5000 J2/kg soil. At 5000 Pi caused 34.8, 34.1 and 33.3% reduction in root weight of Ang. koreana, P. japonicum and Ast. membranaceus, respectively. Greater root gall severity was observed on Ang. koreana and P. japonicum than on Ast. membranaceus at all Pi levels. At 5000 Pi, root gall severity was 5.0, 5.0, and 3.0 on Ang. koreana, P. japonicum and Ast. membranaceus, respectively. Increasing rate of Pi exponentially reduced reproductive factor (Rf) of M. hapla on all of these medicinal plants. However, Rf was higher on Ang. koreana and P. japonicum than on Ast. membranaceus at all Pi levels. The host status of these medicinal plants renders them unsuitable for their use in crop rotation system in M. hapla‐infested fields. 相似文献