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131.
畜产品中药物残留主要包括β-受体激动剂类、抗生素类、性激素类等药物。ELISA检测技术因其灵敏度高、特异性强、仪器设备简单、成本低、方法快速、简便等优点,成为畜产品中药物残留目前最理想的检测技术之一。为了考察试剂盒的各项指标与标示指标是否一致和能否正确使用试剂盒,本文就ELISA检测技术在畜产品中兽药残留检测试剂盒的选择原则和使用注意事项进行了归纳总结。  相似文献   
132.
螺杆转速和含水率对棉籽粉双螺杆挤压脱毒的影响   总被引:2,自引:0,他引:2  
棉籽饼粕是一种优良的蛋白资源,通常含 30%~ 50%的蛋白质, 10%~ 15%的纤维素和其它一些营养成分,其营养价值甚至高于谷类蛋白质。但普通棉籽仁中的棉酚有毒性,食用后会危害细胞、血管和神经,通常它的含量为 0.20%~ 2.0%,远超过国际食用卫生标准 0.04%。我国是产棉大国,每年都有成千上万吨的棉籽饼粕返田作肥料,开发这宝贵的蛋白资源有重要的意义。   解决此类脱毒问题的途径,目前有培育无腺体棉的遗传学法、旋液分离的物理法、添加硫酸亚铁或混合溶剂提取的化学法及微生物发酵的生物学法等等。但在实际处理时它们都或…  相似文献   
133.
施肥及生长调节剂对高羊茅种子产量的影响   总被引:27,自引:4,他引:27  
在辽宁省大连市普兰店地区研究氮肥、氯丁唑和调嘧啶对高羊茅种子产量及其构成要素的影响。结果表明,该地区的气候条件有利于高羊茅的生殖生长和种子发育。施氮后种子产量较对照明显提高,其中以施氮量120kg/hm2(春季施氮量占总施肥量3/4),种子产量最高,可达2473kg/hm2。在抽穗初期使用调嘧啶可显著降低种子的落粒性,减轻收获风险。  相似文献   
134.
Partitioning the respiratory components of soil surface CO2 efflux is important in understanding carbon turnover and in identifying the soil carbon sink/source function in response to land-use change. The sensitivities of soil respiration components on changing climate patterns are currently not fully understood. We used trench and isotopic methods to separate total soil respiration into autotrophic (R A ) and heterotrophic components (R H ). This study was undertaken on a Robinia pseudoacacia L. plantation in the southern Taihang Mountains, China. The fractionation of soil 13CO2 was analyzed by comparing the δ13C of soil CO2 extracted from buried steel tubes with results from Gas Vapor Probe Kits at a depth of 50 cm at the preliminary test (2.03‰). The results showed that the contribution of autotrophic respiration (fR A ) increased with increasing soil depth. The contribution of heterotrophic respiration (fR H ) declined with increasing soil depth. The contribution of autotrophic respiration was similar whether estimated by the trench method (fR A , 23.50%) or by the isotopic method in which a difference in value of 13C between soil and plant prevailed in the natural state (RC, 21.03%). The experimental error produced by the trench method was insignificant as compared with that produced by the isotopic method, providing a technical basis for further investigations.  相似文献   
135.
136.
加强通风和喷雾降温对奶牛生产性能的影响   总被引:4,自引:0,他引:4  
黑白花奶牛是耐寒怕热的家畜,适宜温度范围44~211℃,产奶最适宜温度10℃,当环境温度自21℃升高至35℃,产奶量将大幅下降,乳的组成亦发生变化。合肥地区属于亚热带季风气候,夏季温度高达35℃以上,极端最高温度达40℃,奶牛长时期处于这种环境中,高温引起热应激反应,散热困难,体温升高,采食量减少,增加散热的能量消耗和体蛋白质的分解,造成内分泌活动和酸碱平衡失调乃至死亡。为降低热应激对奶牛生产的影响,我场在夏季采用强制通风和喷雾的措施,可提高奶牛单产达20%的显著效果。1 材料与方法11 喷雾设备111 加压泵…  相似文献   
137.
The effect of dietary methionine (Met) levels on endogenous N and amino acids (AA) flows at different part of the digestive tract of growing goats was determined using a 15N isotope dilution technique. Three goats (25 ± 2.5 kg) were fitted with the ruminal, duodenal and ileal cannulae and allocated to three dietary treatments in a 3 × 3 Latin square design. The dietary treatments consisted of a total mixed ration containing three levels of Met (0.15%, 0.25% and 0.35%) respectively. It was found that at 0.15% Met level, the lowest flow in endogenous N and total AA at the duodenum and ileum occurred. The endogenous N secretion contributed to 26% and 23% of the duodenal and ileal total N flows, respectively, and the proportions were not affected by the dietary Met levels. The duodenal and ileal flows of endogenous total AA were 11.1, 11.8, 11.3 g/d and 2.9, 3.9, 4.1 g/d respectively. The average real digestibility of N was 65%, 87% and 95% in the forestomach, intestine and whole digestive tract respectively.  相似文献   
138.
Effect of Foot and Mouth disease (FMD) vaccination was studied on semen quality parameters of 19 Karan Fries (KF) and eight Murrah (MU) breeding bulls during the period 2002 to 2004 at Artificial Breeding Complex, NDRI, Karnal. A total of non-vaccinated 155 KF and 72 MU bulls' ejaculates were taken as control, while 169 KF and 51 MU bulls' ejaculates, collected after vaccination, were used to study the effect of vaccination stress. The results showed that FMD vaccination had no significant (P > 0.05) effect on ejaculate volume and total volume per day of semen in both KF and MU bulls. Volume of semen increased slightly during post-vaccination period in both the breeds. After FMD vaccination, there was significant (P < 0.01) decrease in mass activity (2.27 ± 0.06 vs. 1.67 ± 0.07 and 2.49 ± 0.09. vs. 1.75 ± 0.10, for KF and MU, respectively), initial motility (56.89 ± 0.03% vs. 44.62 ± 0.02% and 62.26 ± 0.04% vs. 47.08 ± 0.05%, for KF and MU, respectively), sperm concentration (754.19 ± 23.96 vs. 554.14 ± 22.95 × 106/ml and 848.61 ± 33.65 vs. 571.57 ± 39.99 × 106/ml, for KF and MU, respectively), and total sperm output per ejaculate (3,685.94 ± 158.40 vs. 2,781.54 ± 151.70 × 106 and 2,218.75 ± 133.14 vs. 1,582.84 ± 158.20 × 106, for KF and MU, respectively). Application of FMD vaccine had significantly (P < 0.05) adverse effect on most of the seminal attributes during post-vaccination in KF and MU buffalo bulls. So, the spermiograms affected following vaccination suggest that in bovines, the semen collection and preservation should be suspended till normal fertility of sperm is restored to avoid the failure of conception from artificial insemination using such semen.  相似文献   
139.
Pharmacokinetics and milk levels of ceftriaxone were studied in healthy and endometritic cows following single intravenous administration. The drug was detected up to 8 h of dosing in plasma of healthy and endometritic cows and the drug disposition followed three-compartment open model. The values of Vdarea, AUC, t1/2β, ClB, MRT and P/C ratio were 0.50 ± 0.19 L.kg−1, 62.2 ± 23.3 μg.ml−1.h, 1.02 ± 0.07 h, 0.30 ± 0.09 L.kg−1.h−1, 1.55 ± 0.25 h and 0.52 ± 0.27, respectively, in healthy and 1.55 ± 0.52 L.kg−1, 37.0 ± 17.1 μg.ml−1.h, 1.56 ± 0.25 h, 0.56 ± 0.14 L.kg−1.h−1, 2.14 ± 0.34 h and 1.44 ± 0.60, respectively, in endometritic cows. The drug was detected in milk for 36 h after administration. For MIC90 of 0.5 μg.ml−1 the most appropriate dosage for ceftriaxone, would be 9.0 mg.kg−1 repeated at 6 h intervals for the treatment of endometritis in cows.  相似文献   
140.
China was one of the first countries to use artificial insemination (AI) in equids, and it achieved international recognition for its widespread application of AI to commercial horse breeding. This article reviews the history of equine AI in China. The technique originated from the high demand for horses to be used in agriculture, transportation, and the military. Artificial insemination was identified as an ideal tool for Chinese horse breeding to improve the productivity of native horses, especially during 1950-1970. Presently, AI is still practiced commonly in China, and it includes the use of fresh semen and transported cooled semen. The use of frozen semen has also been resumed to broaden the range of elite Sporthorse stallions and to preserve threatened or endangered native breeds. Accurate prediction of the optimum time for insemination depended mainly on transrectal palpation of the mare's ovaries. In addition to controlled methods of insemination, factors like volume and number of spermatozoa in the inseminate and timing and frequency of insemination were optimized to accomplish high fertility rates in the field. Production of hinnies and mules for agricultural labor and donkeys for meat and hide gelatin stimulated a nationwide upsurge of research into the reproductive physiology of and AI technology in donkeys. In the future, there will be further increases in the use of traditional and modern AI techniques in the breeding of Chinese equids.  相似文献   
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