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21.
Experiments were performed on 11 adult Red Sokoto goats (RSG) with the aim of determining their diurnal temperature fluctuations during the harmattan season. The rectal temperatures (RT) of goats were recorded with a standard clinical thermometer every hour from 06:00 to 19:00 hours. The RT of goats rose gradually from its minimum value of 38.3+/-0.1 degrees C at 06:00 hours and attained its peak value of 39.2+/-0.1 degrees C at 18:00 hours (P < 0.001). Thus, the RT values rose concurrently with increase in ambient temperature. The overall mean RT obtained was 38.7+/-0.1 degrees C. The diurnal fluctuation in the RT of the goats was 1.9+/-0.1 degrees C. There was a highly significant correlation between time of day and RT values (r = 0.947, P < 0.001). The results indicate a diurnal rhythm in the RT of the RSG, which agree with the established pattern of fluctuations in the RT of other breeds of goats. The high diurnal range of 1.9+/-0.1 degrees C confirms that the harmattan season is thermally stressful to the RSG.  相似文献   
22.
OBJECTIVE: To identify the types of injuries sustained by horses that competed in steeplechase races and determine the prevalence of and risk factors for those injuries. DESIGN: Prospective study. ANIMALS: 2,680 horses that competed in various types of steeplechase races from 1996 through 2000. PROCEDURE: Data regarding races; environment; equipment problems; the number of horses that entered, started, and finished races; the number of riders that fell; and the number of horses that were slowed or stopped by the rider, ran off the course, fell, and sustained injuries or physical abnormalities during races were collected on a standard form by the official veterinarian who attended each meet. Data from all meets were not recorded; however, in recorded meets, data from every race were reported. RESULTS: Data for 197 hurdle, 65 timber, 76 flat, and 8 mixed races were recorded. Nine (3.4/1,000 horses that started in races) horses died or were euthanatized, and 7 of those were associated with catastrophic musculoskeletal injury. Seven fractures were recorded. Four fractures involved forelimbs, 1 involved a hind limb, and 2 involved the cervical portion of the vertebral column. All horses with fractures were euthanatized. Deep or hard course conditions were associated with an increased risk of breakdown injuries. CONCLUSIONS AND CLINICAL RELEVANCE: Successful development and implementation of strategies to prevent injuries and death in horses in steeplechase races depend on a clear understanding of the types and prevalence of injuries involved and risk factors associated with those injuries.  相似文献   
23.
The expression of surface membrane antigens on peripheral blood monocytes (PBM) of cattle of the Boran and N'Dama breeds activated with recombinant cytokines (TNF-alpha and IFN-gamma) and during experimental infection with Trypanosoma congolense was investigated using monoclonal antibodies (MoAbs) and fluorescein-activated cell sorter (FACS). The surface antigens investigated were C3bi receptor, major histocompartibility (MHC) II complex (Ia antigen) and two monocyte/macrophage (Mphi) differentiation antigens. The study revealed that both cytokines caused the enhancement of the expression of all the PBM surface antigens studied. rBolFN-gammaat low concentrations was more efficient in causing the activation of PBM. While the PBM of Boran cattle were more significantly activated to express the C3bi receptor vis-à-vis the Ia antigen than N'Dama cattle, the reverse was the case with the PBM of N'Dama cattle which expressed more Ia antigens than Boran PBM. Similar results were observed during T. congolense infection in the two breeds of cattle. The significantly higher expression of C3bi receptor and correspondingly lower Ia antigen expression by the PBM of Boran cattle, both during trypanosomosis and in vitro may be responsible for the higher rate of erythrocyte phagocytosis, hence the development of more severe anaemia by Boran cattle during trypanosomosis than N'Dama. In addition, the expression of significantly higher numbers of Ia antigen by N'Dama Mphi, hence are more able to process, present and initiate better trypanosome antigen-specific immune response than Boran cattle during infection. These two attributes are known genetic characteristics of trypanotolerance in cattle.  相似文献   
24.
生猪生产是农业生产的重要组成部份.猪肉是大多数城乡居民的主要副食品,受前几年生猪价格过低,以及2006年以来饲养成本上升和部分地区发生生猪蓝耳病疫情等因素的影响,我国生猪生产出现下滑,造成近几个月猪肉供应编紧,价格出现较大幅度上涨,为了认真贯彻执行《国务院关于促进生猪生产发展稳定市场供应意见》(国务院[2007]22号),  相似文献   
25.
坪用紫羊茅引种选育研究进展   总被引:1,自引:0,他引:1  
紫羊茅是羊茅属中用于草坪草最广泛的草种之一,它具有优良的坪用性状和较强的耐荫性,并且耐粗放管理,近几年来在我国广泛用于休闲娱乐、绿地、观赏和环境保护。本文综述了坪用紫羊茅引种选育的研究进展,指出我国在这一方面研究中存在的问题和今后的发展方向。  相似文献   
26.
红豆草等草种国家级繁育基地建设初见成效   总被引:1,自引:0,他引:1  
蒲翔 《四川草原》2006,(5):58-61
介绍了红豆草等草种国家级繁育基地建设项目情况及取得的主要成果,总结了项目建设的主要经验,提出了项目建设的技术措施及建成后的运行管理措施。  相似文献   
27.
在四川省草原科学研究院牧草试验基地,对在适应性观察中表现较好的引进稿草“川草3号”与对照品种“川草2号”老芒麦和野生稿草于2001-2004年进行了物候期、抗逆性、越冬率、茎叶比及产草量等方面的观测对比,结果表明:“川草3号”稿草在生产性能、适应性、抗逆性等方面都优于对照“川草2号”老芒麦和野生稿草。  相似文献   
28.
不同倍性鸭茅同功酶比较研究   总被引:2,自引:0,他引:2  
采用生化遗传学的方法,对我国亚热带地区几个二倍体和四倍体野生鸭茅不同生育期的酯酶,过氧化物酶同功酶进行了比较研究。结果表明,鸭茅二倍体各品系之间,四倍体各品种(系)之间的同源性较高,遗传差异较小,二倍体与四倍体之间,酯酶,过氧经物酶同功酶等都有较大差异。  相似文献   
29.
近红外光谱技术是一种间接的测量技术,是近年来发展最快、最引人注目的光谱学技术.本文主要就近红外光谱技术的基本原理,光谱预处理及化学计量学方法,光谱影响因素做一概述.重点就近红外光谱技术在牧草品质分析中的应用现状及前景进行论述,以期开辟更广阔的应用领域.  相似文献   
30.
采用苯达松、2,4-D丁酯、高效盖草能(10%乳油)3种除草剂对沟叶结缕草草坪进行了杂草化学防治研究.结果表明,苯达松(25%水剂)每15 kg水可加至80 ml左右,2,4-D丁酯(72%乳油)每15kg水可加至25 ml,高效盖草能(10%乳油)每15kg水可加至10~15 ml,每667m2控制用水25~30kg可取得较好效果.但高温季节除草剂容易对草坪产生药害,施用时应在杂草幼苗期进行,并降低药剂浓度,以提高对草坪的安全性.  相似文献   
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