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Two types of Hepialus larvae with different diets were distinguished in the Sejila Mountain,Tibetan Plateau based on the stable carbon isotope data of the host Hepialus larva of Cordyceps sinensis and its closely adjacent tender plant roots and humus fractions.Type I is the larva chiefly fed by soil humus,and characterized by the δ 13C values of -22.6‰ to-23.4‰,and more than -23.4‰ in its heads.Type II is the larva chiefly fed by tender plant roots,and characterized by the δ 13C values of-24.6‰ to -27.6‰,an...  相似文献   
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蛹虫草(Cordyceps militaris)对药物引起免疫抑制的拮抗作用   总被引:4,自引:0,他引:4  
实验研究蛹虫草对环磷酰胺造成的小鼠免疫抑制的作用。实验选用天然冬虫夏草为阳性对照。给药方式为每天灌胃 0 .2 g生药水煎剂 ,7d后测定其生物学活性。实验结果表明 :小鼠腹腔巨噬细胞的吞噬率由对照组的 13.97%提高到 2 2 .16 %;骨髓细胞的微核数目由对照组的 16 .6×10 -3 降低到 12 .3× 10 -3 ;外周血白细胞由对照组的 70 %提高到 83%。结果证实 :蛹虫草具有明显的拮抗由环磷酰胺造成的免疫抑制的作用 ,与冬虫夏草比较有相似的生物学活性 ,某些作用明显高于冬虫夏草 ,为蛹虫草的医学应用提供了一定的理论依据。  相似文献   
3.
Two types of Hepialus larvae with different diets were distinguished in the Sejila Mountain, Tibetan Plateau based on the stable carbon isotope data of the host Hepialus larva of Cordyceps sinensis and its closely adjacent tender plant roots and humus fractions. Type I is the larva chiefly fed by soil humus, and characterized by the δ 13C values of −22.6‰ to −23.4‰, and more than −23.4‰ in its heads. Type II is the larva chiefly fed by tender plant roots, and characterized by the δ 13C values of −24.6‰ to −27.6‰, and less than −24.6‰ in its heads. Our result has exceeded the traditional understanding that their food sources only come from the tender plant roots, and may provide evidence for choosing cheap and high-quality foods and further establishing artificial habitats in their large-scale reproduction. Supported by the National Key Technology R & D Program (Grant No. 2007BAI32B05)  相似文献   
4.
北虫草菌Y3胞内与胞外多糖的免疫药理研究   总被引:2,自引:1,他引:1  
对北虫草菌Y3胞内与胞外多糖的免疫药理活性进行实验研究。结果表明,北虫草多糖可显著提高小鼠腹腔巨噬细胞吞噬功能,增强血清溶菌酶活力,提高小鼠肝、红细胞SOD活力,并可对抗环磷酰胺引起的外周血白细胞数目下降。北虫草菌Y3多糖对小鼠迟发型超敏反应与溶血空斑实验都有促进作用,提示其对特异性与非特异性免疫的增强作用。  相似文献   
5.
Climate change(CC)and human activities(HA)are the main reasons for the res-toration/degradation of the Qinghai-Tibet Plateau(QTP)grassland.Many related studies have been conducted thus far,but the impact mechanism of CC coupled with HA on QTP remains unclear.We summarized the two main coupling factors in recent years(specifically,in the past five years)and obtained the following conclusions.(1)CC and HA have positive and negative effects on the QTP grassland ecosystem.CC primarily affects grassland ecol-ogy through temperature,humidification,and extreme climate,and HA mainly affects eco-systems through primary,secondary,and tertiary industries and restoration measures.(2)CC coupled with HA affects soil,plants,animals,and fungi/microbes.CC makes the snow line rise by increasing the temperature,which expands the zone for HA.CC also restricts HA through hydrological changes,extreme climate,and outbreak of pikas and pests.Simulta-neously,measures are implemented through HA to control and adapt to CC.Hence,the grassland ecosystem is comprehensively influenced by CC and HA.(3)The grassland eco-system dynamically adapts to the disturbance caused by CC and HA by changing its physi-ological characteristics,distribution range,diet structure,community structure,and physical state.Simultaneously,it responds to environmental changes through desertification,poi-sonous weeds,rodent outbreak,release of harmful gases,and other means.This work can be used as a reference for the sustainable development of the QTP grassland.  相似文献   
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