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951.
Molla W Molla B Alemayehu D Muckle A Cole L Wilkie E 《Tropical animal health and production》2006,38(6):455-462
The present study was undertaken to determine the occurrence, distribution and antimicrobial resistance pattern of Salmonella serovars in apparently healthy slaughtered sheep and goats in central Ethiopia. A total 1224 samples consisting of faeces,
mesenteric lymph nodes, liver, spleen, and abdominal and diaphragmatic muscle samples were collected from 104 sheep and 100
goats. Salmonella was isolated from 12 of 104 (11.5%) sheep and 3 of 100 (3%) goats. Of the total 624 and 600 samples examined from sheep and
goats, 18 (2.9%) and 4 (0.7%), respectively, were Salmonella positive. The 22 Salmonella isolates belonged to 9 different serovars. The common serovars isolated were S.
typhimurium, followed by S.
heidelberg, S.
reading, S.
give, and S.
poona. Seven of the 22 isolates (31.8%) were multidrug-resistant to various antimicrobials. 相似文献
952.
Al-Rukibat RK Ismail ZB Al-Majali AM Al-Zghoul MB 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(2):215-218
BACKGROUND: To the authors' knowledge, there is no information in the literature about normal peritoneal fluid values in ovine species. OBJECTIVES: The purpose of the study reported here was to establish reference intervals for peritoneal fluid from clinically normal Awassi sheep and to compare the values to those in blood. METHODS: Peritoneal fluid and blood samples were collected into tubes containing EDTA, from 40 clinically healthy, nonpregnant, female Awassi sheep, aged 2 to 7 years. Total nucleated cell count (TNCC) was determined using an electronic cell counter. Total protein, albumin, urea, creatinine, and glucose concentrations and aspartate transaminase activity were analyzed using commercially available kits. RESULTS: TNCC (mean +/- SD) of peritoneal fluid was 1.1 +/- 0.87 X 10(3)/microl, with neutrophils (3.9%), lymphocytes (33.5%), macrophages/monocytes (61.2%), and eosinophils (1.4%). Biochemical results in peritoneal fluid were: total protein, 1.7 +/- 0.74 g/dL; albumin, 1.0 +/- 0.04 g/dL; urea, 12.6 +/- 3.95 mg/dL; creatinine, 0.6 +/- 0.19 mg/dL; glucose, 54.8 +/- 6.11 mg/dL; and aspartate transaminase, 23.5 +/- 8.82 U/L. Eosinophil percentage and creatinine concentration did not differ significantly from blood values. CONCLUSION: Baseline values for cytologic and biochemical parameters in peritoneal fluid of Awassi sheep, with comparison to blood, have been generated. Such data may be applicable to other ovine species and can be used in the clinical investigation of ovine abdominal disorders. 相似文献
953.
以滩羊为试验动物,采用30 d、45 d、60 d断奶,4月龄断奶为对照。研究结果表明,羔羊的早期断奶有利于母羊产后和断奶后体况的恢复和母羊发情期的提前到来,以30 d断奶母羊体况恢复最佳和对提前母羊的发情期效果最好。 相似文献
954.
955.
与畜禽经济性状相关的主效基因的研究越来越受到关注。本文就与绵、山羊经济性状相关的主效基因研究进展进行综述,为羊主效基因的进一步研究提供参考。 相似文献
956.
FecB是19世纪80年代在布鲁拉美利奴(Booroola Merino)绵羊中发现的能增加排卵数和产羔数的一个常染色体突变基因,是在绵羊中识别出的第一个高繁殖力主效基因。本研究利用PCR-SSCP以及PCR-RFLP方法对湖羊、小尾寒羊、阿勒泰羊、洼地绵羊共470只的FecB基因进行单核苷酸多态性分析,验证FecB基因为绵羊的高繁殖力的主效基因,并以洼地绵羊为研究对象,检验FecB基因是否为洼地绵羊高繁殖力的主效基因。实验结果表明上述两种方法均能准确判型,稳定可靠性良好,并且判断的结果一致。研究结果显示:上述4个绵羊品种均携带FecB突变,且能证明FecB基因为洼地绵羊高繁殖力的主效基因。 相似文献
957.
[目的]探讨细毛羊毛囊生长期及休止期特异基因的表达模式以及该模式对敖汉细毛羊选育的意义。[方法]通过基因芯片技术对敖汉细毛羊羊毛生长期和休止期的颈部、腹股沟部的上皮基因表达进行检测。[结果]统计分析Ⅰ型内根鞘角蛋白基因KRT25、KRT26、KRT27和KRT28在细毛羊颈部与腹股沟部的表达,发现该基因在细毛羊生长期颈部表达量极显著高于腹股沟部的表达量(差异倍数2,P0.01);对比分析生长期与休止期该基因的表达变化,结果显示在腹股沟部所有芯片涵盖的Ⅰ型内根鞘角蛋白基因的表达都表现出由生长期进入休止期的显著下调(P0.05),除KRT25(LOC443079)外,其他基因的表达变化都在2倍以上。[结论]该研究结果表明Ⅰ型内根鞘角蛋白基因家族的表达与特异部位羊毛密度的控制以及整个毛囊发育生长周期都有着重要的联系。 相似文献
958.
从胚胎发育阶段、饲养层和培养体系等方面对影响绵羊类ES细胞分离、克隆效率的因素进行探讨。结果显示:致密桑葚胚和囊胚的ICM增殖率高于囊胚和孵化囊胚。绵羊类ES细胞在同源绵羊胎儿成纤维细胞(SEF)上生长比较缓慢,最终传代次数也低于小鼠胎儿成纤维细胞(MEF)组。培养液中同时添加胎牛血清(FBS)和Knock-out血清替代品(KSR),绵羊类ES传至7代,添加了碱性成纤维细胞生长因子(bFGF)后,最高可传至8代,而单纯添加KSR或FBS,分别传至4代和5代。对类ES细胞进行AKP染色、核型分析、体外分化试验,证实分离的类ES细胞符合ES细胞的主要特征,而且表达多潜能性细胞因子Nanog。由此认为,致密桑葚胚和囊胚更适合绵羊类ES细胞的体外分离和培养,而且MEF更适合于绵羊类ES细胞的分离传代,培养液中添加5%FBS和15%KSR,比较适合类ES细胞的分离传代,bFGF对绵羊类ES细胞的增殖具有促进作用。 相似文献
959.
Vinayagamurthy Balamurugan Paramasivam Saravanan Arnab Sen Kaushal Kishor Rajak Gnanavel Venkatesan Paramanandham Krishnamoorthy Veerakyathappa Bhanuprakash Raj Kumar Singh 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(3):279-285
This study measured the clinical prevalence of peste des petits ruminants (PPR) among sheep and goats in India between 2003 and 2009 by analyzing clinical samples from suspected cases of PPR that were submitted to the Rinderpest and Allied Disease Laboratory, Division of Virology, IVRI, Mukteswar for PPR diagnosis. PPR outbreaks were confirmed by detecting PPR virus (PPRV)-specific antigen in the clinical samples. Clinical samples (blood, nasal swabs, spleen, lymph node, kidney, liver, intestine, and pooled tissue materials) were taken from a total of 592 sheep and 912 goats in different states of India and screened for the presence of PPRV antigen using a monoclonal antibody-based sandwich ELISA kit. A total of 20, 38, and 11 laboratory-confirmed PPR outbreaks occurred among sheep, goat, and combined sheep and goat populations, respectively. Our findings provide evidence of widespread PPR endemicity in India. The underlying reasons could be variations in husbandry practices in different geographical regions, agro-climatic conditions, and livestock migration. Furthermore, decrease in the number of PPR outbreaks over time might be due to the effectiveness of current live PPR vaccines and timely vaccination of target species. Vaccination against PPR has been practiced in India since 2002 to control this disease. 相似文献
960.