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211.
本试验旨在研究沙葱提取物对舍饲羊肉中氨基酸的影响.试验选用60只蒙古羯羊,按照体重相近原则随机分为4组,对照组饲喂基础日粮,试验组分别添加0.03%、0.06%、0.09%的沙葱提取物.背最长肌中研究结果表明,4个处理组除Asp、Gh、Gly、Lys、Pro比例有显著差异(P<0.05),其它Aa均无显著差异(P>0.05).在臀中肌中,4个处理组除Ala、Cys比例有显著差异(P<0.05),其它Aa均无显著差异(P>0.05).沙葱提取物添加组羊肉中Glu、His、必需氨基酸和鲜味氨基酸均有提高,当添加0.06%的沙葱提取物时,Glu和鲜味氨基酸含量最高. 相似文献
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213.
不同种植制度对土壤质量的影响 总被引:1,自引:0,他引:1
[目的]探讨由大田作物转变为大棚蔬菜生产过程中土壤性状变化及其可能对环境产生的不利影响。[方法]于2007~2009年跟踪调查了上海崇明主要种植制度(露地轮作、温室轮作和温室单作)下农户施肥、灌溉及作物生长状况,并分析了土壤质量的变化。[结果]不同种植制度显著影响土壤质量。与露地轮作相比,温室栽培下过量有机肥和无机肥的投入显著提高了土壤中有机碳、矿质氮、有效磷和可交换钾的含量。温室单作和温室轮作分别导致土壤pH下降0.6和0.4,而露地土壤pH变化不大。同时,温室栽培土壤中EC值、NO3-和Cl-含量均显著高于露地轮作土壤,且随种植年限的增加有增加的趋势,而露地土壤盐分变化不明显。[结论]农户缺乏科学的田间管理指导、一味追求短时期内的高产、过量的施肥灌溉及高复种指数是导致温室土壤严重盐渍化的主要原因。 相似文献
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Shoot and fruit borer, Leucinodes orbonalis Guenee, is a serious pest of eggplant (Solanum melongena L.). Management practices of this obnoxious pest are limited to frequent spray of chemical insecticides. Due to increasing
levels of resistance of L. orbonalis to different insecticides there is an urgent need to test new chemicals. In this study, nine insecticides such as azadirachtin
0.03EC, abamectin 1.8EC, flubendiamide 24WG, chlorpyriphos 20EC, cartap 50SP, carbosulfan 20EC, thiodicarb 75WP, cypermethrin
10EC, and lambdacyhalothrin 2.5EC belonging to different chemical groups were tested against eggplant shoot and fruit borer
in laboratory and field. In laboratory trial, carbosulfan and flubendiamide showed the highest toxicity against fourth instar
larvae of L. orbonalis after 24 and 48 h of exposure, respectively. In field trials, they reduced more than 80% shoot and fruit infestation in winter,
and 80% shoot and 70% fruit infestation in summer over control. Carbosulfan protected the highest amount of healthy fruit
yield in both cropping seasons. Flubendiamide also showed the similar efficacy. Cartap and thiodicarb were moderately effective
in both the seasons. Efficacy of cypermethrin and abamectin was moderate in winter but low in summer. Lambdacyhalothrin and
chlorpyriphos although reduced shoot and fruit infestation of eggplant and protected higher yield as compared to control,
their effectiveness was not satisfactory. The performance of azadirachtin against the pest both in the laboratory and field
trials was the poorest while that of carbosulfan and flubendiamide was the best. Thus, it is suggested that carbosulfan and
flubendiamide may be used for the control of L. orbonalis in eggplant. 相似文献
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218.
Sara Oveissi Abdul Rahman Omar Khatijah Yusoff Fatemeh Jahanshiri Sharifah Syed Hassan 《Comparative immunology, microbiology and infectious diseases》2010,33(6):491-503
The H5 gene of avian influenza virus (AIV) strain A/chicken/Malaysia/5744/2004(H5N1) was cloned into pcDNA3.1 vector, and Esat-6 gene of Mycobacterium tuberculosis was fused into downstream of the H5 gene as a genetic adjuvant for DNA vaccine candidates. The antibody level against AIV was measured using enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition (HI) test. Sera obtained from specific-pathogen-free chickens immunized with pcDNA3.1/H5 and pcDNA3.1/H5/Esat-6 demonstrated antibody responses as early as 2 weeks after the first immunization. Furthermore, the overall HI antibody titer in chickens immunized with pcDNA3.1/H5/Esat-6 was higher compared to the chickens immunized with pcDNA3.1/H5 (p < 0.05). The results suggested that Esat-6 gene of M. tuberculosis is a potential genetic adjuvant for the development of effective H5 DNA vaccine in chickens. 相似文献
219.
Hoque M. A. Skerratt L. F. Rahman M. A. Rabiul Alam Beg A. B. M. Debnath N. C. 《Tropical animal health and production》2010,42(7):1579-1587
A cross sectional survey of duck production was carried out in 2002 on 771 traditional, semiscavenging household duck farms
on the coastal Island of Hatia. We determined the socioeconomic characteristics of duck farmers and their management systems,
identified the factors associated with egg production, and measured the level of selected duck diseases and current preventive
strategies. Household family size varied from 1 to 14 individuals and women were the main caretakers of ducks. Around 34%
of keepers were illiterate. Most duck products (eggs and meat; 85%) were sold at the local market. Duck houses were poorly
ventilated and a variety of bedding materials were used. Feed was available in nearby scavenging areas; however, additional
feed was frequently supplied by farmers. Almost all farmers (96%) ranked the rainy season as the best time for rearing ducks
due to greater feed availability. The annual egg production was 79 eggs per layer with a weight of 48 g and a hatchability
rate of 87%. Egg production varied by zone (p < 0.05). The odds of suboptimal egg production was 0.5 times lower in educated farmers (p = 0.001). The odds of suboptimal egg production was 2.5 times more likely in ducks that attained sexual maturity at >22 weeks
(p<0.001). Most farmers ranked duck plague as the most important disease, followed by duck cholera, botulism, and duck viral
hepatitis. Preventive vaccination was sporadic and used by few farmers (28%). There are significant opportunities for improved
duck production on the Island of Hatia and in Bangladesh generally. 相似文献
220.
高效生物肥料在春季结球生菜上的应用 总被引:2,自引:0,他引:2
为使高效生物肥料能在生产中发挥较大作用,将生物肥料与赤霉素在不同浓度配比下施用,对结球生菜进行大田生产试验.2008-2009年试验结果表明:喷施生物肥料和赤霉素对结球生菜具有一定的增产效果.生物肥料中含有大量有机酸和蛋白酶,能使植物细胞质膜去极化,形成养分离子流入细胞,有效促进结球生菜营养生长,为生殖生长提供足够的养分,从而有利于球茎膨大,产量提高. 相似文献