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为揭示冰鲜鸡生产链中沙门氏菌的分布及传播机制,本研究于2013年7月~2013年12月采集广东某大型一体化养鸡企业下属2个种鸡场、2个孵化场、2个肉鸡场、1个屠宰场和5个销售点样品,用常规法和PCR进行沙门氏菌的分离鉴定,并对分离出的沙门氏菌进行血清学鉴定和PFGE分子分型.种鸡场、肉鸡场、屠宰场和销售点的沙门氏菌的检出率分别为1.46%(7/480)、7.00%(21/300)、62.86%(22/35)和54.67%(41/75),孵化场雏鸡胎粪检出率为1.11%(2/180),死胚检出率为12.00%(9/75).屠宰和销售环节是沙门氏菌污染的重要环节,食品安全风险较高.102株沙门氏菌共产生24种不同的PFGE谱型,从不同环节分离到多组相似度为100%的沙门氏菌,表明冰鲜鸡生产链中存在沙门氏菌沿生产链传播的现象. 相似文献
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青海肉羊业生产现状及发展对策 总被引:3,自引:0,他引:3
针对国内外及青海省肉羊业生产现状和发展趋势,分析了青海省发展肉羊业的有利条件和存在的问题,并从加强对发展肉羊业的组织领导、建立肉羊良种繁育体系、大力开展经济杂交,实现商品肉羊杂交化、组织肥羔生产、加快畜群周转、加大草原建设和饲草料基地建设、培育“龙头企业”、注重肉羊生产加工环节的无公害化、落实疫病虫防治检疫制度等方面,对发展青海肉羊业生产提出了对策。 相似文献
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苍溪县近年来抓住毛兔产业西移的契机 ,采取增投入、普科技、抓饲料、建市场、扶龙头、强领导等措施大力发展长毛兔。一个市场牵龙头 ,龙头连基地 ,基地带农户的大产业 ,大规模 ,大流通 ,大市场 ,大效益的毛兔产业化发展格局已基本形成。 1 999年底 ,全县存栏毛兔 2 0 1 5万只 ,产毛 95 8吨 ,兔业产值达 1 6亿元 ,占牧业总产值的 2 9 4 % ,兔业创税 1 0 0 0余万元。通过养兔 ,全县已有 8 5万余农户摆脱贫困 ,走上了富裕之路 相似文献
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R. Roehe N.P. Shrestha W. Mekkawy E.M. Baxter P.W. Knap K.M. Smurthwaite S. Jarvis A.B. Lawrence S.A. Edwards 《Livestock Science》2009,121(2-3):173-181
Genetic parameters of piglet survival traits and birth weight were estimated on the first generation data of a selection experiment aimed at improving piglet survival using a multiple trait linear and threshold model. Data on 5293 piglets for survival at birth, at day one after birth and during the entire nursing period, as well as individual birth weight and litter size, were recorded in an outdoor production system. Genetic effects of piglet survival traits and birth weight were estimated based on threshold and Gaussian models, respectively, using a Bayesian approach. The statistical model included as fixed effects selection group, parity, gender, fostering, gestation length and month of farrowing and, alternatively, an adjustment for litter size. Direct genetic effects (i.e. the piglet's genetic potential) for piglet survival and birth weight were estimated separately, whereas maternal genetic and environmental effects could only be estimated for the given data structure in a combined litter effect. Posterior means of heritabilities for direct genetic effects of survival at birth, at first day after birth and the entire nursing period, as well as birth weight, were 0.08, 0.07, 0.08 and 0.20, respectively. Genetic correlations among survival traits were in the range of 0.29 to 0.40 and indicate that these traits were mainly attributable to different genetic effects. Genetic correlations between direct effects of survival traits and birth weight ranged between 0.18 and 0.23 and were reduced when weights of stillborn piglets were omitted in the analysis or the traits were adjusted for litter size. The magnitudes of direct genetic effects of survival traits are substantially higher than estimates in the literature, which may indicate that these traits have a higher genetic influence under outdoor conditions. The use of birth weight in the multiple trait estimation provided important information for the estimation of survival traits due to its favourable genetic correlations with survival, its high heritability and its high information content as a continuously measured trait. 相似文献
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Statistical control charts were used to detect process change in pig production. Two charts were tested to detect small deviations in production processes: the cumulative sum (CUSUM) control chart and the exponentially weighted moving average (EWMA) control chart. A Monte-Carlo simulation was used for developing an optimal design of the EWMA and the CUSUM charts. The traits piglets born in total and the return to oestrus rate were considered. Over a given time period, small shifts were purposely implemented to test the performance of the charts. The average time to signal (ATS) and false positive rate (FPR) were taken as classification parameters to evaluate the performance of the charts. All shifts in the number of piglets born in total were detected with CUSUM and EWMA control charts. The trait piglets born in total showed an ATS ranging from 1.3 (FPR = 33.5%) to 6.8 weeks (FPR = 1.2%) using the CUSUM chart. The EWMA chart presented an ATS which ranged between 2.0 (FPR = 14.9%) and 6.3 (FPR = 1.9%) weeks. The application of the CUSUM to the return to oestrus rate resulted in an ATS of 2.6 (FPR = 38.3%) to 15.6 weeks (FPR = 3.0%) and the EWMA chart produced a signal between 4.1 (FPR = 14.5%) and 16.4 weeks (FPR = 1.4%). Both charts appear to be useful tools for tracking commercial swine farm processes and detecting emerging change in process performance. 相似文献