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111.
Hygienic and ecological risks connected with utilization of animal manures and biosolids in agriculture 总被引:2,自引:0,他引:2
In recent years the fate of human and animal pathogen microorganisms as a potential pollutant of the environment has been paid increased attention. Substantial quantities of these compounds and their metabolites are excreted, flushed down the drain, discarded as waste, or left over in animal feedlots. After passing to the sewer, several of these compounds are not adequately eliminated by the methods that are currently used in sewage treatment. Substantial quantities of biosolids and livestock manure end up on agricultural land. Effective sanitation of the environment, particularly of some of its special parts, which can be a source of spreading of diseases, plays an important role in prevention of infectious diseases. In this respect special attention should be paid to the disinfection of infected farm animal excrements. Sanitation of excrements should, on the one hand, ensure effective inhibition of infectious agents and, on the other hand, comply with the requirement of preserving the composition of the manure so it can be used in agricultural production. 相似文献
112.
Nadja E. Sigrist DrMedVet FVH DACVECC 《Journal of Veterinary Emergency and Critical Care》2007,17(2):117-126
Objective: To review the current understanding of dopamine and its use in the prevention and treatment of acute renal failure (ARF). Data sources: Original research articles and scientific reviews. Human data synthesis: Low‐dose dopamine administration has been shown to increase natriuresis and urinary output in both healthy individuals and in a few small studies in human patients with renal insufficiency. However, in several large meta‐analyses, dopamine treatment did not change mortality or the need for dialysis. Due to the potential side effects, the use of dopamine for prevention and treatment of ARF is no longer recommended in human medicine. Veterinary data synthesis: Low‐dose dopamine increases urinary output in healthy animals and animal models of ARF if given before the insult. There are no available studies looking at the effect of low‐dose dopamine therapy in naturally occurring ARF in dogs or cats. Conclusion: Due to the potential side effects of low‐dose dopamine therapy, the results from large human trials, and the lack of information in veterinary medicine, the use of dopamine for treatment of ARF in veterinary patients should be further evaluated. 相似文献
113.
Ki-Soo Park Yong-Soon Lee Kyung-Sun Kang 《Journal of veterinary science (Suw?n-si, Korea)》2006,7(4):343-348
Mesenchymal stem cells (MSCs) have the capabilities for self-renewal and differentiation into cells with the phenotypes of bone, cartilage, neurons and fat cells. These features of MSCs have attracted the attention of investigators for using MSCs for cell-based therapies to treat several human diseases. Because bone marrow-derived cells, which are a main source of MSCs, are not always acceptable due to a significant drop in their cell number and proliferative/differentiation capacity with age, human umbilical cord blood (UCB) cells are good substitutes for BMCs due to the immaturity of newborn cells. Although the isolation of hematopoietic stem cells from UCB has been well established, the isolation and characterization of MSCs from UCB still need to be established and evaluated. In this study, we isolated and characterized MSCs. UCB-derived mononuclear cells, which gave rise to adherent cells, exhibited either an osteoclast or a mesenchymal-like phenotype. The attached cells with mesenchymal phenotypes displayed fibroblast-like morphologies, and they expressed mesenchym-related antigens (SH2 and vimentin) and periodic acid Schiff activity. Also, UCB-derived MSCs were able to transdifferentiate into bone and 2 types of neuronal cells, in vitro. Therefore, it is suggested that the MSCs from UCB might be a good alternative to bone marrow cells for transplantation or cell therapy. 相似文献
114.
115.
滩羊尿对典型草原三种草地植物生长的短期作用特性 总被引:3,自引:0,他引:3
研究了不同尿液浓度和土壤含水量下,羊尿对典型草原植物茵陈蒿、委陵菜和狗尾草生长的短期作用特性。结果表明,不同施尿量施尿后1个月,狗尾草对羊尿沉积的响应为高尿液浓度负效应,低尿液浓度正效应;茵陈蒿和委陵菜为负效应。土壤含水量越高,羊尿对其分蘖(枝)的负效应越低。不同尿液浓度下,三种植物对羊尿响应的负效应顺序为茵陈蒿〉委陵菜〉狗尾草;且其分蘖(枝)对羊尿和土壤水分互作反应的正效应顺序为狗尾草〉委陵菜〉茵陈蒿。具体放牧过程中,可通过家畜适时饮水降低尿液浓度,以降低畜尿对草地的负效应。 相似文献
116.
将人溶菌酶(human lysozyme,hLYZ)cDNA插入由pcDNA3改造而成的pcDNAK表达载体。用获得的重组载体pcDNAKLYZ转染COS-1细胞,经免疫荧光试验证明能进行正确表达。将重组载体注射于哺乳母鼠,取其乳汁进行溶菌酶活性测定,结果显示,分泌在乳汁中的重组hLYZ高达139mg/L。根据乳汁体细胞检测结果,选择健康奶牛和乳腺炎阳性奶牛,分别在干奶时和产犊前2周2次注射重组质粒pcDNAKLYZ,注射途径为乳腺基部穿刺,注射剂量为300μg/乳区,于产犊后1个月采集奶样进行体细胞检测,结果显示,对前一泌乳期发生的奶牛乳腺炎的治愈率为91.5%,对下一泌乳期奶牛孔腺炎的预防有效率王少为96.97%。由此认为。构建的表达hLYZ基因的重组表达质粒,可以替代抗菌素类油乳剂用于干乳期乳腺炎的防治。 相似文献
117.
118.
青藏高原草地退化原因述评 总被引:23,自引:11,他引:23
导致青藏高原草地退化的因子很多,主要有气候、野生动物和人类活动等。在气候因素中以气温和降水的影响为主,短期内气候的变化不会成为草地退化的主导因素,从长期来看,气候变化与草地退化之间的相互作用可引起草地生态系统的退化;野生动物因素中主要以植食性小哺乳动物的影响为主,其危害程度取决于其种群数量的高低,同时大型野生草食动物对草地退化的影响也不容忽视;人类活动因素中主要以家畜过度放牧为主,在一定程度上,家畜放牧强度的高低直接决定草地的退化程度;草地退化是多种因素综合作用的结果。不同地区导致草地退化的主要因素不尽相同,导致青藏高原草地退化最主要的因子是过度放牧和植食性小哺乳动物种群爆发。针对退化的原因,提出了青藏高原退化草地恢复与管理过程中应注意的事项。 相似文献
119.
E.coli K1 strain is a representative strain of neonatal sepsis and meningitis, which causes disease by blood circulation to the brain. The molecular mechanism of E.coli K1 that adhering and invading the brain microvascular endothelial cells (BMECs) and cross the blood brain barrier (BBB) has been focused on by many scholars. In this review, we focused on the gene regulation mechanisms and signaling pathway of E.coli K1 crossing the blood brain barrier to understand the molecular mechanism of the infection caused by E.coli and provide reference for prevention and treatment programs. 相似文献
120.