首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1849篇
  免费   85篇
  国内免费   1篇
林业   58篇
农学   43篇
基础科学   16篇
  184篇
综合类   380篇
农作物   90篇
水产渔业   163篇
畜牧兽医   805篇
园艺   28篇
植物保护   168篇
  2022年   13篇
  2021年   11篇
  2020年   23篇
  2019年   30篇
  2018年   33篇
  2017年   21篇
  2016年   38篇
  2015年   25篇
  2014年   30篇
  2013年   78篇
  2012年   89篇
  2011年   101篇
  2010年   58篇
  2009年   61篇
  2008年   96篇
  2007年   97篇
  2006年   98篇
  2005年   70篇
  2004年   78篇
  2003年   57篇
  2002年   42篇
  2001年   37篇
  2000年   38篇
  1999年   26篇
  1997年   13篇
  1996年   12篇
  1994年   15篇
  1993年   21篇
  1992年   27篇
  1991年   47篇
  1990年   40篇
  1989年   37篇
  1988年   41篇
  1987年   30篇
  1986年   21篇
  1985年   18篇
  1984年   17篇
  1983年   16篇
  1982年   14篇
  1980年   15篇
  1979年   22篇
  1977年   11篇
  1974年   23篇
  1973年   20篇
  1972年   17篇
  1971年   13篇
  1970年   15篇
  1969年   20篇
  1967年   12篇
  1966年   10篇
排序方式: 共有1935条查询结果,搜索用时 15 毫秒
1.
An alpaca and a llama in late stages of gestation were evaluated for lethargy, anorexia, and recumbency. Both camelids had cloudy, white, turbid serum, elevated serum triglyceride (1564, 5658 mg/dL, respectively) and cholesterol (158, 297 mg/dL, respectively) concentrations, and ketonuria. Signs of fetal stress were evident ultrasonographically in the alpaca, and a live cria was delivered by Cesarean section performed under general anesthesia. The alpaca developed severe metabolic acidosis, hepatic lipidosis, and acute renal failure secondary to renal lipidosis and died 36 hours after admission despite medical therapy. Histopathology revealed renal and hepatic lipidosis and neutrophilic pancreatitis. The cria died 72 hours after birth. The llama responded to IV electrolyte, dextrose, and regular crystalline insulin therapy. The pregnancy was maintained, and the llama was discharged from the hospital 20 days after admission. Two months after discharge, the llama gave birth to a live, 5 kg cria. Findings of hypertriglyceridemia, hypercholesterolemia, elevated sorbitol dehydrogenase activity, metabolic acidosis, azotemia, and ketonuria occurred in these two camelids. Based on this report, camelids appear to be similar to both horses and cattle in their response to severe energy imbalances in late gestation.  相似文献   
2.
3.
Dogs were examined ophthalmoscopically to determine the prevalence and type of ocular lesions associated with naturally acquired Rocky Mountain spotted fever (RMSF). In a consecutive series of 11 dogs with serologically confirmed RMSF, 9 had ocular involvement reflecting various degrees of vascular damage, including subconjunctival hemorrhage, hyphema, anterior uveitis, iris stromal hemorrhage, retinal petechiae, and focal areas of retinal edema and perivascular inflammatory cell infiltrate. The ophthalmic lesions generally were mild, and most resolved without complication after systemic administration of appropriate antibiotics. The high prevalence of ocular lesions in these dogs suggested that critical ophthalmologic evaluation is a useful diagnostic tool for the early detection and management of RMSF in dogs.  相似文献   
4.
A 5-year-old female American Quarter Horse was determined to have immune-mediated hemolytic anemia after detection of a positive response to a direct Coombs' test. Penicillin-induced immune-mediated hemolytic anemia was confirmed via a direct antiglobulin test, using penicillin-coated RBC. The horse was clinically improved and the anemia resolved in response to supportive care and discontinuation of penicillin treatment. Penicillin should be considered a possible cause of immune-mediated hemolytic anemia in horses.  相似文献   
5.
6.
7.
8.
9.
1. The acute effects of challenge with Australian T‐strain infectious bronchitis virus (IBV) on renal function were evaluated, following primary vaccination in 1‐d‐old male broilers.

2. Challenge with T‐strain IBV decreased body weight and induced kidney hypertrophy and kidney asymmetry.

3. Haematocrit was reduced in birds challenged with the Australian T‐strain IBV and plasma uric acid was elevated in unvaccinated birds exposed to the IBV challenge.

4. Challenge with T‐strain IBV caused significant increases in urinary water losses, accompanied by decreased urine osmolality and increased fractional excretion of sodium, calcium and potassium.

5. Vaccination at 1‐d‐old with Vic S‐strain IBV provided a limited degree of protection against an heterologous challenge with T‐strain IBV at 15 d of age.  相似文献   

10.
Triple-phase bone scintigraphy was used to evaluate tissue viability in the forelimb of a dog after gunshot injury. This technique was reliable, noninvasive, and easily performed. It was used to complement radiography by providing functional, rather than structural, assessment of tissues on the basis of regional vascular patterns. In this dog, vascular impairment caused by trauma appeared as photopenic or "cold" spots during immediate (vascular), soft tissue and bone phases of the scintigraphic study. On the basis of gross morphologic and scintigraphic findings, forelimb amputation was performed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号