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Diversity and seasonal phenology of aboveground arthropods in conventional and transgenic maize crops in Central Spain 总被引:1,自引:0,他引:1
Gema P. Farins Marta de la Poza Pedro Hernndez-Crespo Flix Ortego Pedro Castaera 《Biological Control》2008,44(3):362-371
One of the major concerns regarding the release of Bt maize is its potential negative impact on non-target organisms present in this crop. In this paper, we compare the temporal phenology and community structure of the aboveground arthropods in commercial Bt maize fields in Central Spain with those of conventional maize crops, with or without an insecticide (imidacloprid) seed treatment, over a period of three years. Spiders, harvestmen, centipedes, ground beetles, rove beetles, carrion beetles, click beetles, earwigs and damsel bugs were captured in pitfall traps every year in sufficient number to provide meaningful phenological data. One predator spider and three omnivorous species of ground beetles have been consistently present in the maize fields: Pardosa occidentalis, Poecilus cupreus, Pseudophonus rufipes and Pseudophonus griseus, respectively. Rove beetles were caught to a lesser extent, with three dominant species: Acrotona aterrima, Philonthus varians and Platystethus nitens. The variability in activity–density patterns of the aboveground fauna was mainly influenced by the year, but no detrimental effects could be attributed to Bt maize. The only exception being the changes detected in rove beetles, although these differences were transitory and varied from year to year. No changes in species richness and diversity indices for spiders and ground beetles resulted from treatments. However, imidacloprid-treated maize caused a reduction in species richness of rove beetles, even though the abundance of the main species was not reduced. Our results suggest that Bt maize could be compatible with natural enemies that are common in maize fields in Spain. 相似文献
43.
【背景】此研究为“十二五”转基因生物新品种培育国家项目中创建新的转基因棉花品种环境安全评价技术而设。【方法】以转双价双成抗虫基因(cry1Ac+cry2Ab)棉和转双价抗虫、抗除草剂基因(cry1Ac+肼强阳)棉为观察品种,非转基因棉赣棉11号为对照品种,在荒地用撒播和3cm深度播种2种方式,于2011年5月一2012年3月对棉花出苗率、株高、生育进程、棉吐絮瓣数、絮瓣脱落率、自生苗等生存竞争能力进行比较,检测、评价其杂草化的风险,并探讨、验证检测技术的可行性。【结果】在荒地条件下,以2种方式播种的转cry1Ac+cry2Ab基因棉和转cry1Ac+EP5P5基因棉与非转基因棉相比,上述各项指标的竞争能力总体上未表现显著优势。【结论与意义】转cry1Ac+cry2Ab基因棉和转cry1Ac+EPSPS基因棉在荒地条件下生长无杂草化风险。同时,研究证明,在荒地自然生态条件下,可以采用撒播和3cm深度播种方法检测新的转基因棉花品种在生存竞争能力上的杂草化风险,在测评上有互为参照效应,为定性评价新的转基因棉花品种的杂草化风险提供了保障。 相似文献
44.
对甜菜夜蛾高毒苏云金芽孢杆菌菌株的选育* 总被引:2,自引:0,他引:2
采用物理诱变——虫体传代模式,选育获得一株对甜菜夜蛾高毒菌株BtCZE 99985。通过摇瓶和40t发酵罐3年10批发酵试验,表明该菌株具有良好的发酵性能。摇瓶试验表明,与出发菌株93005、对照菌株HD-1-580、GC-91相比较,该菌株对甜菜夜蛾的毒效分别提高429%、655%、114%。40t发酵罐发酵试验表明,该菌株对甜菜夜蛾测定的LC50平均值为0.076μL/mL,比GC-91菌株(平均0.213μL/mL)的毒效提高180%。 相似文献
45.
46.
采用浸叶法测定了2003年秋季、2004年春季采自广东惠州、福建福州、浙江杭州和江苏南京的小菜蛾Plutella xylostella田间种群对Cry1Aa、Cry1Ab、Cry1Ac和Cry2Aa以及Bt制剂kurstaki亚种 (Bacillus thuringiensis subsp. kurstaki, Btk)的抗性水平。与敏感品系PHI-S相比,广东惠州田间小菜蛾种群的抗性水平最高,其对Cry1Ab和Cry1Ac的抗性分别达到了168和120倍,均为高抗水平; 对Btk制剂的抗性有47倍,达到了中抗水平;对Cry1Aa和Cry2Aa具有低水平抗性 (分别为5.8和5.6倍)。福建福州、浙江杭州和江苏南京田间小菜蛾种群抗性水平相近,对Cry1Ab和Cry1Ac具有低至中等水平抗性 (8~28倍),对Btk制剂具有低水平抗性 (3.5~7倍),对Cry1Aa和Cry2Aa还没有产生明显抗性。因此,在我国东南沿海地区要注意Btk制剂与Bt其他亚种制剂或其他生物杀虫剂轮换使用,以减小Bt制剂对小菜蛾的选择压力,延缓小菜蛾对Bt抗性的发展。 相似文献
47.
The Canadian Food Inspection Agency (CFIA) regulates environmental releases of plants with novel traits, which include transgenic plants such as Bt crops. Bt crops are regulated in Canada because they express insect resistance novel to their species. Commercialization of crops with novel traits such as the production of insecticidal Bt proteins requires an approval for environmental release, as well as approvals for use as feed and food. Environmental factors such as potential impacts on non-target species are considered. Insect resistance management (IRM) may be imposed as a condition for environmental release of Bt crops to delay the development of resistance in the target insect. Bt potato and European corn borer-resistant Bt corn have been released with mandatory IRM. The CFIA imposes an IRM plan consisting of appropriate refugia, education of farmers and seed dealers, and monitoring and mitigation. Industry, regulators, government extension staff and public researchers provide expert advice on IRM. 相似文献
48.
转基因烟草中Bt毒蛋白基因的表达行为 总被引:9,自引:0,他引:9
构建了高效植物表达载体pBinMoBc,该载体携带超强表达复合启动子OM及Ω因子控制下的CryIA(c)基因。采用根癌土壤杆菌(Agrobacterum tumefaciens(Smith et Townsend)Conn)介导的方法转化烟草(Nicotiana tabacum L.),ELISA检测表明,大多数转基因烟草中CryIA(c)基因表达量均超过0.1%,最高可达0.255%;转基因烟草 相似文献
49.
Bacillus thuringiensis (Bt) Cry proteins are used as components of biopesticides or expressed in transgenic crops to control diverse insect pests worldwide. These Cry toxins bind to receptors on the midgut brush border membrane and kill enterocytes culminating in larval mortality. Cadherin proteins have been identified as Cry toxin receptors in diverse lepidopteran, coleopteran, and dipteran species. In the present work we report a 185 kDa cadherin (AdCad1) from larvae of the lesser mealworm (Alphitobius diaperinus) larvae as the first identified receptor for Cry3Bb toxin. The AdCad1 protein contains typical structural components for Cry toxin receptor cadherins, including nine cadherin repeats (CR9), a membrane-proximal extracellular domain (MPED) and a cytosolic region. Peptides corresponding to the CR9 and MPED regions bound Cry3Bb toxin with high affinities (23 nM and 40 nM) and significantly synergized Cry3Bb toxicity against A. diperinus larvae. Silencing of AdCad1 expression through RNA interference resulted in highly reduced susceptibility to Cry3Bb in A. diperinus larvae. The CR9 peptide fed with toxin to RNAi-treated larvae restored Cry3Bb toxicity. These results are evidences that AdCad1 is a functional receptor of Cry3Bb toxin and that exogenously fed CR9 peptide can overcome the effect of reduced AdCad1expression on Cry3Bb toxicity to larvae. 相似文献
50.