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21.
为探讨巴马小型猪在达芬奇机器人微创手术中的麻醉管理策略,以丙泊酚麻醉作诱导,异氟醚维持麻醉的复合麻醉方法对巴马小型猪进行全身麻醉,同时用达芬奇机器人对其分别进行心脏、肺脏、肝脏和胃的微创手术,于术前、术中及术后监测巴马小型猪动脉血气和血流动力学变化。结果各组试验猪均顺利完成手术,手术平均时间(166±34)min,麻醉时间(181±38)min,气胸(气腹)时间(122±33)min,在整个麻醉过程及苏醒过程中,各组试验猪安全平稳,未出现体动表现。由此可见,该麻醉方法可用于达芬奇机器人手术系统,且为人医临床应用中的麻醉管理奠定基础。  相似文献   
22.
Antibodies can swiftly provide therapeutics to target disease-related molecules discovered in genomic research. Antibody engineering techniques have been actively developed and these technological innovations have intensified the development of therapeutic antibodies. From the mid-1990’s, a series of therapeutic antibodies were launched that are now being used in clinic. The disease areas that therapeutic antibodies can target have subsequently expanded, and antibodies are currently utilized as pharmaceuticals for cancer, inflammatory disease, organ transplantation, cardiovascular disease, infection, respiratory disease, ophthalmologic disease, and so on. This paper briefly describes the modes of action of therapeutic antibodies. Several non-clinical study results of the pathological changes induced by therapeutic antibodies are also presented to aid the future assessment of the toxic potential of an antibody developed as a therapeutic.  相似文献   
23.
将“精益管理思维”应用于高校图书馆管理,试图从新视角为解决诸如图书馆利用率不高、图书经费不足及树立图书馆形象等实际问题,从而顺应社会及时代的发展趋势。  相似文献   
24.
本研究系统探讨了果园和畜禽养殖的种养结合型生态模式,分析研究了“猪-沼-果”、“草-鸡-果”两种生态模式下的猪、鸡生产性能,畜舍空气质量以及苹果的产量和质量。研究结果表明:生态养殖模式下生长肥育猪和鸡的增重显著高于庭院养殖(P<0.05),分别提高了17.46%和29.28%;猪舍、鸡舍空气中的CO2和NH3比庭院猪舍、鸡舍显著降低(P<0.05);苹果产量比单纯果园平均分别提高28.97%和21.15%,含糖量分别相对提高6.79%和6.36%。  相似文献   
25.
通过调查确定了新源县则克台镇春秋草地的4种利用方式:打草、自由放牧、分段放牧、划区轮牧,对比分析了不同利用方式下的土壤理化性质。结果表明,自由放牧方式土壤砂粒含量最高,平均达到21.23%,粉粒含量最低,且在10~20 cm土层显著高于划区轮牧方式(P<0.05)。4种利用方式下,土壤容重为1.08~1.26 g·cm-3,土壤没有表现出压实效应。放牧利用方式下土壤有机质、碱解氮、有效磷含量高于打草地,其中,划区轮牧和自由放牧草地土壤有机质含量高于分段放牧方式,自由放牧方式仅使土壤表层碱解氮显著升高,其土壤速效钾和有效磷的含量均低于分段放牧和划区轮牧。因此,划区轮牧和分段放牧是研究区较为合理的利用方式,可防止土壤养分降低。但是,与划区轮牧相比,分段放牧使土壤表层砂粒含量增高,容重增大,有机质含量降低,所以,采用分段放牧时,应适当降低利用强度。  相似文献   
26.
The associations between feeding activities and environmental variables inform animal feeding tactics that maximize energetic gains by minimizing energy costs while maximizing feeding success. Relevant studies in aquatic animals, particularly marine mammals, are scarce due to difficulties in the observation of feeding behaviors in aquatic environments. This data scarcity concurrently hinders ecosystem-based fishery management in the context of small toothed-cetacean conservation. In the present study, a passive acoustic monitoring station was deployed in an East Asian finless porpoise habitat in Laizhou Bay to investigate potential relationships between East Asian finless porpoises and their prey. The data revealed that porpoises were acoustically present nearly every day during the survey period. Porpoise detection rates differed between spring and autumn in concert with activities of fish choruses. During spring, fish choruses were present throughout the afternoon, and this was the time when porpoise vocalizations were the most frequently detected. During autumn, when fish choruses were absent, porpoise detection rates decreased, and diurnal patterns were not detected. The close association between fish choruses and finless porpoise activities implies an “eavesdropping” feeding strategy to maximize energetic gains, similar to other toothed cetaceans that are known to engage similar feeding strategies. Underwater noise pollution, particularly those masking fish choruses, could interrupt finless porpoises’ feeding success. Fisheries competing soniferous fishes with finless porpoise could impact finless porpoise viability through ecosystem disruption, in addition to fishing gear entanglement.  相似文献   
27.
28.
The aim of this study was to evaluate the accuracy of serum beta-hydroxybutyrate (beta-OHB) measurements for the diagnosis of diabetic ketoacidosis (DKA) in dogs. One hundred sixteen diabetic dogs were prospectively enrolled in the study: 18 insulin-treated (IT) diabetic dogs that had a positive urine ketone test and 88 untreated, newly diagnosed diabetic dogs. Venous blood gas tensions and pH, serum glucose and urea nitrogen (SUN), and electrolyte (Na+, Cl-, and K+) and urine acetoacetate (AA) concentrations were measured concurrently with serum beta-OHB concentrations. On the basis of laboratory findings, the patients were assigned to I of 3 groups: diabetic ketoacidosis (n = 43); diabetic ketosis (DK, n = 41); and nonketotic diabetes (NDK, n = 31). Serum beta-OHB concentrations differed significantly (P < .001) among the study groups. Although marked differences in beta-OHB concentrations were found, a considerable overlap exists between the distributions of dogs with DK and those with DKA. The overall accuracy of beta-OHB determination as a diagnostic test for DKA, determined by the area under the receiver operating characteristic (ROC) curve, was 0.92. In the 1.9- to 4.8-mmol/L range, serum beta-OHB determination sensitivity varied from 100 to 35.7%, whereas specificity varied from 39 to 100%. The cutoff value of 3.8 mmol/L showed the best equilibrium between specificity (95%), sensitivity (72%), and likelihood ratio (14.8). We concluded that the quantitative measurement of serum beta-OHB may be a potential tool for diagnosing and monitoring ketosis and ketoacidosis in diabetic dogs.  相似文献   
29.
何峰  李向林  仝宗永  马钊 《草地学报》2020,28(1):273-278
本研究旨在探讨紫花苜蓿(Medicago sativa L.)混播草地放牧利用的生产潜力和集成全草型集约化肉羊放牧育肥技术模式。2017-2018年,在位于河北省廊坊市的中国农业科学院国际农业高新技术产业园内开展了2年羔羊育肥的划区轮牧试验,研究了紫花苜蓿混播草地的地上生物量、育肥羊增重以及羊肉品质的变化规律。结果表明:混播草地地上生物量超过11.2 tDM·hm-2,5月份紫花苜蓿混播草地的粗蛋白为20.92%,每公顷紫花苜蓿混播草地可满足51只育肥羊、放牧育肥150天,每只增重30 kg所需的干物质、代谢能和粗蛋白三个方面的全部需求。与此同时,紫花苜蓿混播草地还可以显著增加羊肉中欧米伽3型多不饱和脂肪酸的含量,n-6/n-3比例为2.72,羊肉健康品质显著提高。以紫花苜蓿混播草地为基础的全草型肉羊放牧育肥技术具有广阔的应用前景,对我国苜蓿产业以及草地畜牧业发展具有重要意义。  相似文献   
30.
The ratio between maximal small intestinal (SI) diameter and the height of the body of the fifth lumbar vertebra (L5) in radiographs has been reported as a diagnostic test in dogs with suspected intestinal obstruction. In order to assess the effect of the SI/L5 ratio on the accuracy of radiographic diagnosis of intestinal obstruction, lateral abdominal radiographs of 37 dogs with small intestinal obstruction and 48 nonobstructed dogs were mixed and examined independently by six observers who were unaware of the final diagnosis and who represented a range of experience. Observers first examined radiographs subjectively and stated the likelihood of obstruction (definitely not, probably not, equivocal, probably, definitely). Observers subsequently reexamined the radiographs, determined the SI/L5 ratio, and again stated the likelihood of obstruction. The most frequent cause of obstruction was foreign body (29/37, 78%). Dogs with SI obstruction had a significantly larger median SI/L5 ratio than nonobstructed dogs (P = 0.0002). Using an SI/L5 ratio of 1.7 for diagnosis of intestinal obstruction, sensitivity and specificity were 66%. Use of the SI/L5 ratio was not associated with increased accuracy of diagnosis for any observer, regardless of experience, hence this test may have no diagnostic impact.  相似文献   
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