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以硝酸纤维膜为固相载体,利用沙门氏菌多价血清和辣根过氧化物酶(HRP)标记制备的羊抗兔IgG,成功地建立对香肠的Dot-ELISA检查法,同时,采用常规分离培养鉴定技术作对照试验。结果显示,在86份香肠中,用Dot-ELISA检出沙门氏菌阳性为36份,阳性率为41.86%;而常规分离培养鉴定技术检出沙门氏菌阳性为34份,阳性率为39.53%,两种方法的阳性符合率为86.17%,经统计分析,t=0.311 1,p>0.05,两种方法差异不显著。 相似文献
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猪圆环病毒Ⅱ型PCR检测方法的研究 总被引:5,自引:0,他引:5
【目的】建立快速、简便、特异的检测猪圆环病毒II型的PCR方法;【方法】根据已发表的猪圆环病毒II型基因序列设计合成了一对引物,用酚-氯仿法抽提可疑病料中的病毒DNA,应用PCR技术对猪圆环病毒进行基因扩增,PCR产物进行序列测定;以猪瘟病毒、猪伪狂犬病毒、猪细小病毒为对照,进行特异性试验;取部分病料进行重复性试验;【结果】PCR方法扩增出了长度为702bp的片段,扩增产物经测序和序列分析表明扩增的序列为PCV2序列;猪瘟病毒、猪伪狂犬病毒、猪细小病毒的PCR扩增均为阴性,与预期结果一致;部分病料PCR重复检测5次,检测结果完全一致;【结论】PCR检测方法可以对猪圆环病毒病作出敏感、特异、准确地诊断,该方法检测的基因最低模板量为2×10-5ng/ml。 相似文献
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In CDMA communication system, the relativities between users result in Multiple Access Interference (MAI). With the increase of users, MAI becomes the main jam of broadband CDMA communication system. Multi-User Detection (MUD) is the most important technology of anti-jamming in the broadband CDMA communication system, which can eliminates MAI effectively by using the information of all user signals to detection single. This paper analyze the expression of system capability without MUD and with MUD, and puts forward the way to increase system capability by using MUD. Then the influence of MUD on CDMA system capability is discussed by MATLAB emulation. Basing analysis and emulation, the conclusion is got: the higher the MUD efficiency, the better the improvement of CDMA system capability; under the same MUD efficiency, the lower data rate, the smaller inter-cell interference, the lower the ratio of bit energy to power spectrum, the better the improvement of CDMA system capability. 相似文献
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Bashar W. Shaheen Chengming Wang Calvin M. Johnson Bernhard Kaltenboeck Dawn M. Boothe 《Veterinary microbiology》2009,139(3-4):379-385
Fluoroquinolones are used to treat infections caused by Escherichia coli in canine and feline veterinary patients, particularly those infecting the urinary tract. The gyrA gene is a primary target causing fluoroquinolone resistance in Gram negative coliforms, with mutations in codons 83 and 87 generally associated with high-level of resistance E. coli clinical isolates. We have developed a fluorescence resonance energy transfer (FRET) quantitative PCR to identify enrofloxacin-resistance in clinical E. coli isolates that carry mutations in codons 83 and 87 of gyrA. This real-time quantitative PCR assay is rapid, economical, and sensitive compared with cultured antimicrobial susceptibility testing. The assay identified as few as four genome copies per reaction from culture and 19 genome copies in urine. For the 70 isolates tested, the sensitivity was 87.5% (95% CI = 75–95.3%) (n = 42/48), specificity was 100% (95% CI = 87.3–100%) (n = 22/22), whereas accuracy was 91.4% (95% CI = 82.3–97%) (n = 64/70). Furthermore, we were able to accurately differentiate between the wild type and mutants E. coli directly from infected canine urine samples (n = 5) within 2 h. These results were confirmed by sequence alignments of the PCR products and comparison with the susceptibility testing. The FRET-PCR assay appears to have promising clinical application as an early diagnostic tool for rapid and sensitive detection and differentiation of the level of fluoroquinolone resistance among clinical E. coli isolates that may facilitate design of the dosing regimen. 相似文献
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大豆炸荚表型易受环境影响,炸荚相关研究的关键在于如何获得精准的表型。以遗传背景较近且炸荚表型差异较大的2份栽培大豆为材料,利用烘箱对2个品种完熟期不同部位的豆荚进行炸荚率检测,烘干温度和持续时间各设置5个处理。结果表明,不同处理下大豆各部位的炸荚率无显著差异,炸荚率与烘干温度及持续时间呈显著正相关;不同品种大豆炸荚率在60℃、11h后的处理均存在显著性差异,综合炸荚检测的便利、安全及种子发芽率的影响,最终确定烘干温度60℃、持续时间11~13h为最佳检测条件。 相似文献