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31.
青杨叶锈病的综合防治技术 总被引:2,自引:2,他引:2
采用林业技术措施与化学防治相结合的防治方法,连续4年在齐齐哈尔市林业局对小黑杨叶锈病进行防治,取得了明显的防治效果。从中筛选出最佳防治组合为,株距8cm或15cm,重打底叶或轻打底叶、25%粉锈宁1000×液进行喷雾。防治效果平均为36.64%,苗木减少损失率平均为8.69%,苗木平均增长率为51.38% 相似文献
32.
Qingru Zhang Yaodi Ni Hongbin Guo Chunguang Wang 《Frontiers of Agriculture in China》2007,1(4):478-480
In order to investigate the effects of a Chinese herbal formula Heat-stress-releasing on the antioxidant function in dairy
cows, ten dairy cows were randomly divided into the control group and the experimental group, with five cows in each group.
All the cows were fed with a basal diet. The animals in the experimental group were given with 220 g of herbs per day in addition
to the basal diet. The trial was conducted for 14 days. Blood samples were taken from the vena cava at day 0, day 7, and day
15, respectively. The antioxidant statuses were examined. The results are as follows. (1) Heat-Stress-releasing formula can
significantly increase the milk yield of dairy cows under heat stress. Compared with the control group, the milk yield of
the herb-treated group increased by 14.01% (P<0.05), 14.32% (P<0.05) and 15.01% (P<0.05) in prophase, metaphase and anaphase of the test, respectively. (2) Heat-Stress-releasing formula can increase significantly
the antioxidant status of the heat stressed dairy cows. Compared with the control group, the superoxide dismutase (SOD) activity
increased by 45.93% (P<0.01) at day 7 and by 54.40% (P<0.01) at day 15. The Glutathioneperoxidase (GSH-PX) activity of the test group increased by 17.99% (P<0.05) at day 7 and 25.98% (P<0.01) at day 15. The total antioxidant capacity (T-AOC) of the test group increased by 43.64% (P<0.01) at day 7 and 46.35% (P<0.01) at day 15. The malondaldehyd (MDA) content of test group declined by 23.88% (P<0.01) at day 7 and 25.32% (P<0.01) at day 15. 相似文献
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34.
Jing Tu Fengying Lu Shuang Miao Xintao Ni Pan Jiang Hui Yu Linlin Xing Shengqing Yu Chan Ding Qinghai Hu 《Veterinary microbiology》2014,168(2-4):395-402
Riemerella anatipestifer causes epizootic infectious disease in poultry and serious economic losses especially to the duck industry. However, little is known regarding the molecular basis of its pathogenesis. The ability to acquire iron under low-iron conditions is related to the virulence of a variety of bacterial pathogens. In this study, a sip (Riean_1281) deletion mutant CH3Δsip was constructed and characterized for iron-limited growth, biofilm formation, and pathogenicity to ducklings. Results showed that siderophore-interacting protein (SIP) was involved in iron utilization and the sip deletion significantly reduced biofilm formation and adherence to and invasion of Vero cells. In addition, the sip gene was absent in 1 of 24 (4.17%) virulent strains and 2 of 3 (66.7%) avirulent strains of R. anatipestifer, and the sip gene from six R. anatipestifer strains, which belong to serotypes 1, 2, and 10, respectively, shared 100% amino acid identities to those of R. anatipestifer strains DSM15868 and RA-GD. These results suggested that siderophore-mediated iron acquisition may be an important iron-uptake pathway in R. anatipestifer. Animal experiments indicated that the median lethal dose of the CH3Δsip mutant in ducklings was about 35-fold higher than that of the wild-type CH3 strain. Thus, our results demonstrated that R. anatipestifer SIP was involved in iron acquisition and necessary for its optimal virulence. 相似文献
35.
饲料中添加激素类等药剂促进僵鳗生长及复壮的研究 总被引:2,自引:0,他引:2
在工厂化、高密度、全人工控制的养鳗条件下,使用雌二醇、牛肝糜维生素、甲基睾丸素、强的松等药剂,可以显著地促进僵鳗的生长和复壮,在生产中可以取得较好的经济效益。同时,本试验对于露天止水式和水库网箱养鳗也有普遍的意义。 相似文献
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38.
研究以不同年限(0 a、1 a和2 a)毛竹—灵芝复合系统为对象,对比分析灵芝不同种植年限的毛竹林土壤理化性质、酶活性等17个土壤质量指标的差异,并基于主成分分析对其土壤质量进行评价,旨在为毛竹林下种植灵芝提供参考。结果表明:随着灵芝种植年限的延长,毛竹林土壤含水率、孔隙度和通气度呈先升高后降低的变化趋势,而土壤容重呈先降低后升高的变化趋势;土壤pH值随种植年限的延长逐渐升高,有利于缓解土壤酸化;土壤有机质、全氮、全磷、全钾、速效养分含量和土壤酶活性均随种植年限的延长呈逐渐升高的变化趋势,且种植2 a显著高于0 a(P<0.05)。综合分析土壤理化性质以及酶活性等指标,毛竹林下种植灵芝后,其土壤质量指数均显著高于未种植的毛竹林地,且随种植年限的延长逐渐升高,说明灵芝种植有利于提高毛竹林地土壤质量。 相似文献
39.
Analysis of petal anthocyanins to investigate coloration mechanism in herbaceous peony cultivars 总被引:1,自引:0,他引:1
Petal coloration and anthocyanin compositions of 41 herbaceous peony cultivars were analyzed. Anthocyanins were identified by high-performance liquid chromatography–electrospray ionization-mass spectrometry (HPLC–ESI-MSn) coupled with photodiode array detection (DAD). Peonidin-3,5-di-O-glucoside (Pn3G5G), pelargonidin-3,5-di-O-glucoside (Pg3G5G), cyanidin-3,5-di-O-glucoside (Cy3G5G), peonidin-3-O-glucoside (Pn3G), and cyanidin-3-O-glucoside (Cy3G) were the five major anthocyanins in herbaceous peony cultivars. Deep purple or reddish purple cultivars contained 4–5 anthocyanins, whereas pink cultivars only contained Cy3G5G and Pn3G5G, and their contents were much lower than those of purple cultivars. According to the chemical structures of three anthocyanidins in association with petal coloration, flowers were classified into three phenotypes: 1. “Pn, Cy, and Pg” (all purple flowers including two pink flowers); 2. “Pn, Cy” (pink flowers); 3 “Pn” (light pink and white flowers). The coloration mechanisms of cultivars with the pink and purple flowers were quite different. Correlations between lightness (L*) and chroma (C*), chromatic component a* and total anthocyanins (TA) value, a* and co-pigmentation index (CI) showed opposite tendencies, whereas L* and TA showed the same tendency in each group. High contents of Pn3G5G and Pg3G5G may responsible for the purple coloration of herbaceous peony cultivars. 相似文献
40.
中国果树类病毒的发生及其研究进展(英文) 总被引:4,自引:0,他引:4
概述了在中国发生且己鉴定明确的5种果树类病毒,即苹果绣果类病毒(Apple scar skin viroid,ASSVd)、梨泡状溃疡类病毒(Pear blister canker viroid,PBCVd)、葡萄黄斑类病毒-1(Grapevine yellow speckle viroid-1,GYSVd-1)、柑橘裂皮类病毒(Citrus exocortis viroid,CEVd)和桃潜隐花叶类病毒(Peachlatent mosaic viroid,PLMVd)的研究进展,包括病害的首次发现、症状特征、发病规律、检测方法与防治对策以及这些类病毒的生物学与分子生物学特性。 相似文献