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151.
152.
At concentrations near 2 × 10?4M, barban, chlorpropham, and phenmedipham are inhibitors of the electron transfer in potato and mung bean mitochondria. The inhibition seems to be localized in the flavoprotein region. It affects preferentially the exogenous NADH dehydrogenation, in potato mitochondria (I50, 10?4M). Succinate dehydrogenation is less inhibited. At noninhibiting concentrations, the studied carbamates cannot uncouple the oxidative phosphorylations. Photosynthesis is completely inhibited by 2.10?7M phenmedipham, 5 × 10?5M barban, and 2 × 10?4M chlorpropham. The inhibition takes place at the PS II level. Moreover, barban and chlorpropham are uncouplers of the photophosphorylations for concentrations between 5 × 10?5 and 5 × 10?4M. The effects observed on mitochondrial respiration can also be found on respiration of Acer cultured cells. The effects on isolated chloroplast photosynthesis are also observed for slightly higher concentrations on cultured Chlorella and on pea and oat leaf fragments. 相似文献
153.
This study reports the sero-prevalence of viral infections in sheep in Peru. Serum samples were collected from 34 mature healthy rams located in 3 different geographic regions of the country (north, central and south). The sera were tested for antibodies to the following viruses: respiratory syncytial virus (RSV); parainfluenza 3 (PI-3) virus; bovine viral diarrhea/border disease (BVD/BD) virus; bovine herpesvirus 1 (BHV-1); bluetongue (BT) virus; ovine progressive pneumoniae (OPP) virus; bovine leukosis virus (BLV). The serological studies showed that 47% were positive for RSV; 82% for PI-3; 3% for BVD/BD virus; 49% for BT virus; 13% for OPP virus. Antibodies were not detected to bovine herpesvirus 1 or to bovine leukosis virus. 相似文献
154.
155.
周德义 《湖南农业大学学报(自然科学版)》2003,(5)
在《道德经》中 ,老子运用一分为三的思维方式 ,围绕着“道”这一中心概念的逐步展开 ,构建了充满着辩证法的哲学体系 ,成为中华文化的奇丽瑰宝。论述了“道”为“一”、为“无”、为“无为”、为“自然”的一分为三的哲学内涵 ;“自然”为老子哲学体系的开端 ;“道”的“万物得一以生”、“反者道之动”、“物壮则老”、凡事“守中”的一分为三的作用和意义 ;求“道”的一分为三的过程 ;并以此讨论宇宙的起源 ,世界的形成 ,事物的产生、变化和发展的规律 ,以及人类社会的种种矛盾及其解决的方式 ;还讨论了黑格尔对老子一分为 相似文献
156.
为充分发挥波尔山羊种公羊的作用,对精液高倍稀释各个技术环节进行了多方面的试验研究。采用新鲜羊奶稀释液进行了7个不同稀释倍数的试验,结果表明5倍与8倍稀释组情期受胎率分别为91.4%和91.5%,差异不显著(P>0.05);其它各组之间差异均显著或极显著(P<0.05或P<0.01);各组的情期受胎率随着稀释倍数的增大逐渐下降,15倍稀释组为84.0%,20倍为76.0%,25倍为68.8%,30倍为53.3%。25倍以下的稀释倍数,输入有效精子数在1000万以上,生产上是可以应用的。稀释液的筛选试验表明鲜奶稀释液受胎率较高;二次稀释法比一次稀释提高受精率9%(P<0.05);子宫颈深部输精比子宫颈口输精提高受胎率95.5%(P<0.01);10倍以上稀释有利于精液常温保存。 相似文献
157.
深圳碧海湾高尔夫球场草坪春季杂草及防除策略研究 总被引:11,自引:2,他引:9
对深圳碧海湾高尔夫球场草坪进行调查,发现春季草坪杂草有95种,分属26科80属。阔叶杂草有75种,占杂草总数的78.95%;半日子叶杂草20种,占杂草总数的21.05%。对球道和长草区或边坡的杂草发生特点分别进行分析。针对杂草的发生来源和特点,提出了草坪杂草的防除策略。 相似文献
158.
Although it is well known that judicious use of adjuvants can increase the performance of foliage-applied sprays of many agrochemicals, little information is available in the public domain about their ultimate effects on pesticide residues in treated crops. In the present work, the influence of Agral (polyoxyethylene nonylphenols), Toil (methyl esters of rapeseed fatty acids) and Bond (styrene-butadiene copolymers) on surface and crop residues of diclofop-methyl/diclofop and propiconazole in wheat and field beans was investigated using a model system simulating field practice. Pesticides were applied as commercial formulations, diclofop-methyl 378 g litre(-1) EC (Hoegrass) and propiconazole 250 g litre(-1) EC (Tilt), at their maximum approved rates, 1135 g AI ha(-1) and 125 g AI ha(-1), respectively, both in the presence or absence of the maximum rate recommended for each candidate adjuvant. No detectable residues of diclofop-methyl or propiconazole were found in wheat 35 days after any of the four applications. However, residues of diclofop were present in this crop, and those from applications containing Agral (0.07 mg kg(-1) fresh weight (FW)) or Bond (0.08 mg kg(-1) FW) were significantly lower than those with no adjuvant (0.14 mg kg(-1) FW) or Toil (0.16 mg kg(-1) FW). Unlike wheat, residues of both diclofop and propiconazole were detected in field beans after harvest. Significantly higher residues of the former were recorded from the applications with Agral or Bond (ca 0.32 mg kg(-1) FW) than with those with no adjuvant or Toil (ca 0.15mg kg(-1) FW). All the propiconazole applications containing adjuvants showed a similar significant increase in residues (0.10-0.16 mg AI kg(-1) FW) over the no-adjuvant treatment (0.05 mg kg(-1) FW) in this crop. There appeared to be little agreement between the apparent amounts of uptake, as indicated by the rates of decline of surface residues up to 5 days after application, and final residues in either target species. On wheat, surface residues of diclofop-methyl decreased from initially ca 20 to as little as 0.02 mg kg(-1) FW using adjuvants; the corresponding values for propiconazole were ca 2 to ca 0.03 mg kg(-1) FW. Recoveries of diclofop-methyl from the surfaces of field beans were much higher than those from wheat, declining from ca 30 to only ca 6 mg kg(-1) FW during the course of 5 days; the corresponding residues for propiconazole were ca 2 mg to 0.15 mg kg(-1) FW. These findings are discussed in relation to uptake results obtained with radiolabelled pesticides and adjuvants in the laboratory, and to the mandatory requirements for pesticide residue data for the authorised use of adjuvants in the UK. 相似文献
159.
加大建设新农村的农业财政投资力度研究 总被引:1,自引:0,他引:1
张彩彬 《四川畜牧兽医学院学报》2006,4(2):28-33
农业是维持我国社会稳定和国民经济持续健康发展的基础产业,农业具有“准公共产品”属性,决定了政府必须介入农业领域进行投资与保护,农业财政投资与农业发展密切相关。论文在对财政支持与农业发展理论思考的基础上,针对当前我国农业财政投资的现状和存在的问题进行了研究,对产生问题的宏观制度性根源进行了分析,并提出了相应的政策措施。 相似文献
160.
对浙江省夏秋蚕品种薪杭,白云,丰1和54A等进行了充血复壮改良,基本稳定后的复壮系与现行生产系进行了生产性能的比较试验。结果表明复壮系在各项性状都有一定的提高,其中龄期经过,各品种的复壮系与生产系之间差别不大,只有薪杭丙和白云丙稍有延长。全茧量和茧层量基本上复壮系都比生产系有所提高。生命率差异比较大,奠中薪杭的复壮系低下生产系,差异达到显著水平,白云复壮系略微低于白云甲,但高于白云乙,丰1的复壮系与生产系无明显差异,54A则是复壮系高于生产系。良卵数除薪杭丙比薪杭甲略低外,其他品种的复壮系都比生产系显著提高,有的甚至达到极显著水平。说明复壮系在生产性能上有较大的改良,有一定的推广应用价值。 相似文献