全文获取类型
收费全文 | 10692篇 |
免费 | 791篇 |
国内免费 | 111篇 |
专业分类
林业 | 988篇 |
农学 | 527篇 |
基础科学 | 90篇 |
2664篇 | |
综合类 | 694篇 |
农作物 | 587篇 |
水产渔业 | 1045篇 |
畜牧兽医 | 3933篇 |
园艺 | 188篇 |
植物保护 | 878篇 |
出版年
2024年 | 18篇 |
2023年 | 82篇 |
2022年 | 142篇 |
2021年 | 274篇 |
2020年 | 269篇 |
2019年 | 210篇 |
2018年 | 499篇 |
2017年 | 509篇 |
2016年 | 514篇 |
2015年 | 412篇 |
2014年 | 457篇 |
2013年 | 704篇 |
2012年 | 843篇 |
2011年 | 760篇 |
2010年 | 456篇 |
2009年 | 370篇 |
2008年 | 585篇 |
2007年 | 608篇 |
2006年 | 485篇 |
2005年 | 466篇 |
2004年 | 400篇 |
2003年 | 398篇 |
2002年 | 394篇 |
2001年 | 317篇 |
2000年 | 258篇 |
1999年 | 205篇 |
1998年 | 35篇 |
1997年 | 44篇 |
1996年 | 35篇 |
1995年 | 26篇 |
1994年 | 20篇 |
1993年 | 17篇 |
1992年 | 63篇 |
1991年 | 43篇 |
1990年 | 43篇 |
1989年 | 49篇 |
1988年 | 38篇 |
1987年 | 42篇 |
1986年 | 47篇 |
1985年 | 48篇 |
1984年 | 38篇 |
1983年 | 37篇 |
1982年 | 19篇 |
1979年 | 32篇 |
1978年 | 32篇 |
1977年 | 28篇 |
1974年 | 26篇 |
1973年 | 45篇 |
1972年 | 30篇 |
1971年 | 26篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
会计人员委派制是会计管理体制改革中的一项新举措。它具有加强会计监督、遏制腐败和防止会计信息失真等积极的现实意义。在本文中对高校会计人员委派制的可行性、委派的程序等做了积极的探讨 ,以利于我国高校会计委派制的实施 相似文献
992.
利用经济计量模型分析发现 :工农业总产值、公路营运里程以及居民消费价格指数是影响中国公路货物运输市场的主要因素。在此基础上进一步分析了制约中国公路基础设施建设的原因 ,并给出了相关政策建议 相似文献
993.
María Delclaux Covadonga Talavera Manuel López Jose Miguel Sánchez María Isabel García 《Journal of zoo and wildlife medicine》2002,33(3):283-285
A 17-mo-old captive-born female red panda (Ailurus fulgens fulgens) presented with a sudden onset of lameness in its left hind leg was diagnosed radiographically as having possible severe, bilateral Legg-Calve-Perthes disease with fracture of the great trochanter of the left femur. Surgical repair of the fracture was performed using pins and a tension band wire through a lateral approach to the hip. This is the first case reported at Madrid Zoo-Aquarium, where 63 individuals have been bred over 15 yr. 相似文献
994.
Febantel at a dose level of 5 mg kg-1 had a lethal efficacy of 54.1% against the adult worm and 69.5% against the migrating larvae of Trichinella spiralis in rats. When administered at 15 mg kg-1, it demonstrated lethal effects of 94.4, 92.5 and 74.7% against adult, young and encysted larvae, respectively. Infected rats treated with 300 mg kg-1 died. Thiabendazole had efficiencies of 96.4 and 83.3% against intestinal and migrating early muscle phases, respectively, and was 42% effective against the encysting phase. 相似文献
995.
996.
The dynamics of hematological, protein, mineral and electrolytic profile was examined clinically in nine calves when the hemoconcentration was induced experimentally. The hemoconcentration occurred after diarrhea caused by the per os application of 12 g saccharose per one kg of live weight. The hemoconcentration culminated six hours after application. The calves where the hemoconcentration did not exceed the critical value were included in the first group, and the calves with the extreme hemoconcentration values in the other group. In the first group (with the increasing hemoconcentration degree), a statistically significant increase was found in the values of hematocrit, erythrocytes, hemoglobin, total protein in blood serum and total immunoglobins and a statistically insignificant increase in the levels of leucocytes, inorganic phosphorus, serum calcium and sodium. Serum potassium and magnesium showed the inverse dynamics, i. e. the decrease. In the second group (with the extreme hemoconcentration), hyperkalemia and slight hypermagnesemia were identified, while the other parameters showed deviations similar to those observed in the first group. After the rehydration of animals by a preparation without any influence on the studied parameters, the hemoconcentration and the parameters under study stabilized, while in the second group the hemoconcentration was increasing even during the rehydration and the levels of serum potassium and magnesium showed different tendencies. As follows from the results, in the calves suffering from scours accompanied by hemoconcentration the correction of the parameters of metabolic profile is necessary. 相似文献
997.
998.
999.
1000.
M R Hidalgo Argüello N Díez-Ba?os B Martínez-González F A Rojo-Vázquez 《Veterinary parasitology》2001,102(1-2):143-150
Thirty ewes naturally infected with Sarcoptes scabiei var. ovis, were allocated into three groups of 10 animals each. Animals in groups B and C were treated on day 0 and on days 0 and +10, respectively, with moxidectin 1% injectable at a dose of 0.2mg moxidectin/kg body weight (BW). Group A remained untreated. Seven days before treatment, the geometric mean of Sarcoptes scabiei var. ovis per square centimeter of skin in groups A, B and C were not significantly different. From the day of treatment to the end of the trial, the average number of mites/cm(2) increased in untreated animals and decreased in groups B and C, but these values were higher for group C. Active lesions produced by S. scabiei var. ovis consistently increased during the trial in the untreated animals; in group B the minimum count occurred on day +56 this reduction being more evident in group C (no lesions on days +49 and +56). Also in this group, the number of cured animals was 100%, therefore, the application of two treatments with moxidectin (group C) showed higher efficacy than a single treatment (group B). Body condition score decreased in the three experimental groups along the trial. All animals were individually weighed on days -1, +28 and at the end of the trial. No adverse reactions were observed in the animals treated with 0.2mg moxidectin/kg BW. 相似文献