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71.
A cross-sectional survey was conducted in Sudan to determine sero-prevalence and risk factors associated with Neospora caninum infection in non-vaccinated dairy herds and to assess importance of the disease. Blood samples were collected from a total of 262 animals from 25 herds. Sera were tested for antibodies against N. caninum using ELISA test. The prevalence rates of N. caninum antibodies in cattle were high both at herd level (44%) and at individual animal level (10.7%). Herd level infection rates were similar in Khartoum State (43.7%) and at Gazira States (44.4%). The overall prevalence rates were higher (16.1%) in Gazira State than in Khartoum State (9%) but with no significant variation. The sero-prevalence at individual animal level was significantly higher (p < 0.05) in animals with history of abortion (12.8%) than in apparently healthy animal (11.3%), animal with history of infertility (8.1%), or neonatal death of calves (4.3%). In addition, significantly higher (P < 0.05) sero-prevalence was observed in samples collected during the rainy season (6.87%) than winter (3.05%) or summer (0.76%). However, no significant differences in sero-prevalence due to locality, animal breed, sex, and age were observed (p > 0.05). This preliminary study reveals for the first time the existence of natural N. caninum infection in Sudan. Also, the findings of the present study indicated that this disease is highly prevalent in two major areas of dairy production in the country, and this calls for control strategy to be implemented.  相似文献   
72.
Wang R  Wang F  Zhao J  Qi M  Ning C  Zhang L  Xiao L 《Veterinary parasitology》2012,187(3-4):534-537
The prevalence of Cryptosporidium spp. was investigated in scale quail (Coturnix coturnix japonica) farms in Henan Province, China between September 2006 and August 2007. One thousand eight hundred and eighteen fecal samples from 47 quail farms in five areas were collected for the examination of Cryptosporidium oocysts. The overall prevalence of Cryptosporidium was 13.1% (95% CI 13.1±1.6%) (29 of 47 farms), with 72-100-day-old quails having the highest prevalence (23.6%, 95% CI 23.6±2.6%) (χ(2)=64.91; ρ<0.01). The highest prevalence was observed in autumn (21.8%, 95% CI 21.8±3.1%) and the lowest in winter (χ(2)=74.83; ρ<0.01). Two hundred and thirty-nine Cryptosporidium-positive samples were analyzed by PCR-restriction fragment length polymorphism (RFLP) analysis of the small subunit (SSU) rRNA gene, and 42 were further analyzed by DNA sequencing of the PCR products. Two Cryptosporidium species were identified, Cryptosporidium baileyi in 237 birds on 29 farms, and potentially zoonotic Cryptosporidium meleagridis in only two birds on two farms. These findings may suggest that quails are not a major source of zoonotic Cryptosporidium in the study area.  相似文献   
73.
Remotely sensed observations of rangelands provide a synoptic view of vegetation condition unavailable from other means. Multiple satellite platforms in operation today (e.g. Landsat, moderate-resolution imaging spectroradiometer [MODIS]) offer opportunities for regional monitoring of rangelands. However, the spatial and temporal variability of rangelands pose challenges to consistent and accurate mapping of vegetation condition. For instance, soil properties can have a large impact on the reflectance registered at the satellite sensor. Additionally, senescent vegetation, which is often abundant on rangeland, is dynamic and its physical and photochemical properties can change rapidly along with moisture availability. Remote sensing has been successfully used to map local rangeland conditions. However, regional and frequently updated maps of vegetation cover in rangelands are not currently available. In this research, we compare ground measurements of total vegetation cover, including both green and senescent cover, to reflectance observed by the satellite and develop a robust method for estimating total vegetation canopy cover over diverse regions of the western United States. We test the effects of scaling from ground observations up to the Landsat 30-m scale, then to the MODIS 500-m scale, and quantify sources of noise. The soil-adjusted total vegetation index (SATVI) captures 55% of the variability in ground measured total vegetation cover from diverse sites in New Mexico, Arizona, Wyoming, and Nevada. Scaling from the Landsat to MODIS scale introduces noise and loss of spatial detail, but offers inexpensive and frequent observations and the ability to track trends in cover over large regions.  相似文献   
74.
LRH-3、PMSG、HCG对人工授精母蓝狐产仔效果影响的比较(Ⅲ)   总被引:1,自引:0,他引:1  
通过PMSG +LRH - 3和PMSG +HCG的组合使用 ,结果表明 ,使用PMSG +LRH - 3的试验组母狐的产仔率比对照组提高了 2 0 % ,胎平均产仔数提高了 0 2只。而使用PMSG +HCG组合母狐的产仔率与对照组相同 ,但胎平均产仔数提高了 0 5只。  相似文献   
75.
在海南大田国家级自然保护区围栏内用食痕法(evidence of feeding on forage)观测海南坡鹿Cervus eldi hainanus(简称坡鹿)对18种草本和18种灌木类饲草的采食部分占整株草本植株或占整枝灌木主枝条的尺寸比,同时测定各饲草的酸性洗涤纤维(ADF)含量.结果显示,按旱季与雨季的(全年)平均值,坡鹿对草本类饲草的采食尺寸比为49.29%,对灌木类饲草为57.3%;草本类饲草的ADF含量为9.91%,灌木类饲草为9.19%;无论草本还是灌木类,坡鹿的采食尺寸比随饲草ADF含量的增加而显著降低.研究表明,在大田自然保护区围栏内,坡鹿对ADF含量在10%以上的饲草不喜食,饲草纤维物质含量是坡鹿在围栏内扩充采食部位以增加营养摄入量的限制性因子,在旱季种植并收割饲草投喂坡鹿时,应避免其纤维物质含量增高.  相似文献   
76.
几种草被植物的水土保持效应研究   总被引:7,自引:5,他引:7  
马琦  王琦 《草业科学》2005,22(10):72-74
利用小型观测场,对比了几种草被植物地降水、径流量、土壤侵蚀量和土壤的物理性质.结果表明, 与裸地相比,草被植物可以增加土壤的覆盖度,减少降水的径流系数,减少土壤侵蚀量,其中百脉根Lotus corniculatus的效应最为明显.草被植物可以减小土壤容重,增加土壤空隙率,使土壤蓄水保水能力增加,同时提高土壤入渗速率和土壤的抗蚀性,其中百脉根地土壤含水量和入渗速率最大,苇状羊茅Festuca arundinacea地崩解所需时间最长.如苇状羊茅地、葛藤Pueraria lobata地、百脉根地和空旷地0~2 m土层土壤平均含水量分别是15.74%,15.83%,16.06%和14.61%,苇状羊茅、葛藤、百脉根地土壤完全崩解所需时间分别比空旷地多780,627,704 min.  相似文献   
77.
以3头安装有永久性瘤胃瘘管的泌乳前期荷斯坦奶牛为试验动物,在精粗比为55:45的日粮条件下,采用Insacco法测定了奶牛常用饲料瘤胃内干物质和淀粉的降解规律。试验结果表明。不同饲料干物质和淀粉的降解率不同。能量饲料中,麸皮干物质和淀粉的瘤胃降解率高于玉米:蛋白质饲料中,干物质和淀粉的降解率由高到低顺序依次是豆粕〉胡麻饼〉棉粕:常用粗料中,玉米青贮干物质和淀粉的降解率均高于青干草。  相似文献   
78.
生物炭-土壤结皮对土壤水分入渗和蒸发特征的影响   总被引:1,自引:0,他引:1  
为提高降水资源利用效率和选择适宜生物炭覆盖量,采用垂直一维定水头入渗法,研究土壤结皮(生物炭覆盖量为0×104 kg/hm2)、单倍炭-土壤结皮(生物炭覆盖量为3×104 kg/hm2)和双倍炭-土壤结皮(生物炭覆盖量为6×104 kg/hm2)对土壤入渗和蒸发特征的影响.结果 表明:生物炭-土壤结皮的累计入渗量、初始...  相似文献   
79.
云南省德宏州动物卫生监督所通过抽检发现,辖区内某兽药经营服务部涉嫌销售劣兽药。经该县农业局立案调查,认定当事人违法事实清楚,证据充分,根据《兽药管理条例》规定,依法给予了行政处罚。本文重点介绍了案件来源、调查过程、处理情况等执法内容。分析了案件定性、执法主体适格、自由裁量权应用、保护当事人合法权益等问题,以期为同类案件查处提供参考。  相似文献   
80.
全混合日粮(TMR)是现代奶牛场普遍采用的饲喂技术。本文就目前我国奶牛养殖场(户)使用TMR日粮应具备的条件及使用方法进行介绍。  相似文献   
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