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   502篇
  免费   35篇
  国内免费   1篇
林业   10篇
农学   3篇
基础科学   1篇
  24篇
综合类   118篇
农作物   66篇
水产渔业   31篇
畜牧兽医   258篇
园艺   4篇
植物保护   23篇
  2020年   9篇
  2016年   10篇
  2015年   6篇
  2014年   10篇
  2013年   17篇
  2012年   15篇
  2011年   9篇
  2010年   7篇
  2009年   6篇
  2008年   13篇
  2007年   7篇
  2006年   12篇
  2005年   14篇
  2004年   11篇
  2003年   15篇
  2002年   5篇
  2001年   12篇
  2000年   17篇
  1999年   15篇
  1998年   10篇
  1997年   9篇
  1995年   10篇
  1994年   9篇
  1993年   7篇
  1992年   10篇
  1991年   7篇
  1990年   15篇
  1989年   10篇
  1988年   5篇
  1987年   6篇
  1985年   6篇
  1984年   6篇
  1983年   5篇
  1978年   5篇
  1975年   6篇
  1974年   7篇
  1971年   8篇
  1970年   12篇
  1969年   6篇
  1966年   7篇
  1950年   4篇
  1949年   7篇
  1948年   7篇
  1946年   9篇
  1945年   7篇
  1944年   6篇
  1943年   13篇
  1941年   6篇
  1940年   5篇
  1939年   4篇
排序方式: 共有538条查询结果,搜索用时 15 毫秒
71.
72.
73.
74.
This report describes a three-year-old male domestic longhaired cat which was presented with generalised pruritus, alopecia and ulcerative dermatitis. All four feet showed evidence of nail shedding and there was widespread scarring of the skin of the back. Clinicopathological investigations suggested a mechanobullous disease. The condition was unresponsive to attempted medical therapy which included antibiotics, glucocorticoids and vitamin E supplementation.  相似文献   
75.
One hundred eighty-five dogs with histologically confirmed, measurable malignant tumors were used in a study to determine the toxicity of the anthracycline antitumor antibiotic, doxorubicin, which was administered once or twice (at a 21-day interval) at the rate of 30 mg/m2 of body surface area, iv. During this study, 7 dogs died as a direct result of doxorubicin-induced toxicosis and 16 died as a direct result of the malignant neoplastic disease. Each dog was evaluated for signs of toxicosis for 3 weeks after the last dose was administered (15 dogs received 1 dose, 170 dogs received 2 doses) or until the dog died, whichever came first. The most common signs of toxicosis were vomiting, diarrhea, colitis, anorexia, and pruritus. The probability of doxorubicin-induced toxicosis decreased significantly (P less than 0.0001) in inverse relationship to body weight. Dogs with signs of toxicosis during the 21-day interval from administration of the first dose of doxorubicin were 17.2 times (P less than 0.01; 95% confidence interval; 5.5, 54.2) more likely to develop signs of toxicosis during the 21-day interval from the second dose of doxorubicin. The performance status of each dog was evaluated using a modified Karnofsky performance scheme; the only time the performance status was adversely affected to a significant extent by doxorubicin-induced toxicosis was during the 21-day period, starting with the second dose (P less than 0.0001).  相似文献   
76.
SUMMARY The arterial supply and venous drainage of 62 left and 5 right ovine adrenal glands is described, and the contribution of individual arteries to successful adrenal gland autotransplantation was evaluated. Arterial flow was measured by direct collection from the draining adrenal vein. Assessment of function of the transplanted adrenal gland was made from survival of the sheep and by the cortisol response to infusion of ACTH and the aldosterone secretory response to infusion of angiotensin II or potassium. For the left adrenal, the principal arterial supply was from the renal artery in 21 (34%), a lumbar artery in 32 (52%), and the anterior mesenteric artery in 3. The total blood flow was 5.0 ± SEM 0.4 mL/min, the flow from the renal branch 2.3 ± 0.3 mL/min, and the principal lumbar branch 2.6 ± 0.3 mL/min. Venous drainage from the left adrenal was via a major adrenal vein to the left renal vein, but additional tributaries to the renal vein were present in 26% . The arterial supply to the adrenal is regional and omission of a branch at transplantation could result in infarction of portion of the gland. By defining arterial supply and measuring blood flow, selection of the appropriate artery or multiple arteries can achieve an adrenal gland autotransplant survival of 90% .  相似文献   
77.
Eighteen budgerigars with clinical signs of 'going light' were euthanased and examined post mortem; ingluvitis caused by Trichomonas gallinae infection was present in seven birds, proventriculitis associated with the presence of megabacteria in eight birds and in three birds both conditions were present. Haematological examinations of blood taken from the living birds showed that those with T gallinae infection had normal white cell counts whereas those in which megabacteria were present had significant leucocytosis and heterophilia. Some birds in both groups were anaemic. The findings suggest that infection with megabacteria may be responsible for a proportion of cases of 'going light' in budgerigars and that haematological examination can establish this diagnosis in living birds.  相似文献   
78.
79.
80.
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