全文获取类型
收费全文 | 9539篇 |
免费 | 704篇 |
国内免费 | 2篇 |
专业分类
林业 | 200篇 |
农学 | 233篇 |
基础科学 | 13篇 |
815篇 | |
综合类 | 358篇 |
农作物 | 694篇 |
水产渔业 | 401篇 |
畜牧兽医 | 7222篇 |
园艺 | 69篇 |
植物保护 | 240篇 |
出版年
2024年 | 8篇 |
2023年 | 117篇 |
2022年 | 88篇 |
2021年 | 163篇 |
2020年 | 261篇 |
2019年 | 123篇 |
2018年 | 262篇 |
2017年 | 266篇 |
2016年 | 233篇 |
2015年 | 288篇 |
2014年 | 426篇 |
2013年 | 507篇 |
2012年 | 507篇 |
2011年 | 591篇 |
2010年 | 379篇 |
2009年 | 442篇 |
2008年 | 443篇 |
2007年 | 391篇 |
2006年 | 344篇 |
2005年 | 299篇 |
2004年 | 357篇 |
2003年 | 333篇 |
2002年 | 305篇 |
2001年 | 290篇 |
2000年 | 214篇 |
1999年 | 174篇 |
1998年 | 198篇 |
1997年 | 196篇 |
1996年 | 167篇 |
1995年 | 168篇 |
1994年 | 141篇 |
1993年 | 158篇 |
1992年 | 190篇 |
1991年 | 161篇 |
1990年 | 208篇 |
1989年 | 148篇 |
1988年 | 120篇 |
1987年 | 154篇 |
1986年 | 61篇 |
1985年 | 83篇 |
1984年 | 86篇 |
1983年 | 84篇 |
1982年 | 37篇 |
1981年 | 13篇 |
1980年 | 10篇 |
1978年 | 11篇 |
1977年 | 5篇 |
1974年 | 5篇 |
1972年 | 5篇 |
1968年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
Benny J. Woody DVM MS Michael J. Murphy DVM PhD AIlen C. Ray PhD Robert A. Green DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(1):23-28
The clinical signs and laboratory changes of brodifacoum (BDF) intoxicated dogs and their response to vitamin K1 treatment were examined. Brodifacoum, a second-generation anticoagulant rodenticide, was fed to four dogs for 3 consecutive days producing a cumulative dose of 1.1 mg BDF/kg body weight. Clinical observations of the animals were made daily throughout the study. Monitored laboratory parameters included: one-stage prothrombin time (OSPT), activated partial thromboplastin time (APTT), activated coagulation time (ACT), complete blood counts, thrombocyte counts, and serum chemistry values. Response to vitamin K1 therapy was evaluated clinically and by laboratory tests. Serum BDF concentrations were monitored. Inappetence and hemorrhagic tendencies were exhibited by day 5 postrodenticide exposure. One-stage prothrombin time, APTT, and ACT were 25% greater than time zero values at 24, 24, and 72 hours postdosing, respectively. All laboratory parameters returned to normal within 48 hours of initiating vitamin K1 therapy (0.83 mg/kg orally, TID for 5 days). Serum brodifacoum concentrations were highest (1065-1215 ng/mL) during the 3 days after BDF dosing and were detectable (3.0-7.5 ng/mL) until day 24 postexposure. A mean BDF elimination half-life of 6 +/- 4 days was observed. 相似文献
32.
33.
34.
35.
SHARON L. ULLMAN DVM MS MICHAEL M. PAVLETIC DVM Dipiomate ACVS GEOFFREY N. CLARK DVM 《Veterinary surgery : VS》1991,20(6):385-391
Surgical stapling equipment was used to perform open antiperistaltic side-to-side ("functional end-to-end") entero-anastomoses in 20 dogs and 4 cats. Twenty-one anastomoses healed uneventfully. Seven animals with severe bacterial peritonitis required open peritoneal drainage and delayed abdominal closure. There was postoperative leakage at the anastomotic site in two dogs and a localized abscess at the staple line in one cat. No long-term complications occurred in follow-up periods of 3 to 29 months. 相似文献
36.
37.
38.
Kevin Kline PhD Leonard P. Frey PhD Jonathan H. Foreman DVM MS Joseph T. Lyman DVM MS 《Journal of Equine Veterinary Science》2005,25(8):349-354
Changes in blood gases, pH, and plasma electrolyte concentrations in response to intravenously infused sodium bicarbonate (NaHCO3) and sodium acetate (NaCH3CO2) solutions (1.34 mEq/mL) in 5 light breed mares were investigated. Jugular venous blood samples were collected before and after completion of the infusions in 20-minute intervals for 200 minutes. Infusion of sodium bicarbonate and sodium acetate caused significant (P < .00l) increases in blood pH and bicarbonate ion concentration that persisted throughout the collection period. The elevation in blood pH and bicarbonate ion concentrations was greater (P < .01) for sodium bicarbonate than for sodium acetate immediately after the completion of the infusions but was not different (P > .05) thereafter. There were significant reductions (P < .01) in plasma-ionized calcium and potassium after infusion of both sodium bicarbonate and sodium acetate. This study found that significant metabolic alkalosis in horses and corresponding shifts in electrolyte concentrations can be induced by intravenous infusion of solutions of either sodium bicarbonate or sodium acetate, and they persist for at least 3 hours. These data show that the short-term elevation in pH and bicarbonate ion concentration is momentarily higher after infusion of sodium bicarbonate. This is likely due to the direct infusion of bicarbonate ions in the sodium bicarbonate treatment, such that further metabolism is not required to be effective. However, the longer-term alkalosis did not differ between isomolar solutions of sodium bicarbonate and sodium acetate. 相似文献
39.
How to perform transvenous electrical cardioversion in horses with atrial fibrillation 总被引:1,自引:1,他引:1
M. Kimberly J. McGurrin DVM Dipl ACVIM Peter W. Physick-Sheard BVSc MSc FRCVS Daniel G. Kenney DVM Dipl ACVIM 《Journal of Veterinary Cardiology》2005,7(2):109
Electrical cardioversion of atrial fibrillation is a well-established technique for restoration of sinus rhythm in humans. While transthoracic cardioversion is more commonly used, transvenous electrical cardioversion (TVEC) has been reported as having higher efficacy at substantially lower energy levels. In horses, treatment of atrial fibrillation has essentially been limited to the administration of quinidine salts either orally or intravenously. TVEC provides an alternative to quinidine salts, especially for those animals in which quinidine is neither effective nor tolerated. The present report details this technique in horses, discusses possible complications of the procedure, and provides guidance for successful outcome. Still and video images are used to illustrate details with regard to TVEC techniques in horses. Please view supplemental material for the videos. 相似文献
40.