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   330篇
  免费   22篇
  国内免费   35篇
农学   4篇
  8篇
综合类   70篇
农作物   1篇
水产渔业   18篇
畜牧兽医   282篇
园艺   2篇
植物保护   2篇
  2024年   4篇
  2023年   8篇
  2022年   13篇
  2021年   25篇
  2020年   25篇
  2019年   21篇
  2018年   11篇
  2017年   14篇
  2016年   13篇
  2015年   13篇
  2014年   16篇
  2013年   20篇
  2012年   20篇
  2011年   22篇
  2010年   17篇
  2009年   18篇
  2008年   15篇
  2007年   13篇
  2006年   14篇
  2005年   13篇
  2004年   8篇
  2003年   7篇
  2002年   10篇
  2001年   6篇
  2000年   10篇
  1999年   9篇
  1998年   3篇
  1997年   1篇
  1996年   2篇
  1995年   2篇
  1993年   1篇
  1990年   3篇
  1989年   1篇
  1988年   1篇
  1985年   1篇
  1981年   1篇
  1975年   1篇
  1974年   1篇
  1973年   3篇
  1956年   1篇
排序方式: 共有387条查询结果,搜索用时 15 毫秒
31.
以加利福尼亚兔为试验材料,研究了双酶梭菌制剂对家兔生长及肠道消化酶活性的影响.试验用45日龄断奶加利福尼亚仔兔24只,随机分为2组,每组12只,雌雄各半.对照组饲喂基础日粮,试验组在基础日粮中按1g/kg添加双酶梭菌制剂.饲喂30d后,测定家兔的增重和消化道消化酶活性.结果表明,日粮中添加双酶梭菌制剂后,可促进家兔的生长和肠道中的消化酶活性,提高饲料的利用率.  相似文献   
32.
吉林省黄牛“猝死症”的病因学研究   总被引:2,自引:0,他引:2  
1994年以来,对吉林省黄牛“猝死症”的病因进行了多方面的研究,包括细菌学检验、病毒学检验、人工感染试验、毒物检验、牛毛硒元素分析及病尸病理形态学观察。结果表明,A型魏氏梭菌是主要病原菌,其他细菌有协同作用;牛冠状病毒或粘膜病病毒感染、缺硒等为本病的诱因  相似文献   
33.
我国主要经济动物魏氏梭菌分离及血清型鉴定   总被引:8,自引:0,他引:8  
对分离于7种经济动物的98株魏氏梭菌疑似物进行理化性质鉴定表明,分离菌符合魏氏梭菌特征。中和试验证实,分离于兔、狐狸、貉、水貂、麝鼠、犬的菌株均为A型;分离于鹿的菌株85.4%(35/41)为A型,14.6%(6/41)为C型,说明目前我国经济动物魏氏梭菌感染以A型为主。  相似文献   
34.
产气荚膜梭状芽孢杆菌病的流行与致病机制   总被引:19,自引:2,他引:17  
产气荚膜梭状芽孢杆菌是人和动物肠道的正常菌群,亦是条件性致病菌,该菌感染主要由毒素导致的毒血症致病,因此,有针对地选用类毒素预防接种,才能防止本病流行。  相似文献   
35.
鼠害控制综合配套技术试验研究   总被引:5,自引:0,他引:5  
采用饵料引诱剂 ,不同灭鼠药品 ,不同拌饵浓度 ,不同施饵方法对高原鼠兔进行了灭治试验 ,结果以Y1 、Y2 作为引诱剂 ,分别以 0 .5%的比例拌入饵料 ,引诱效果较为明显。用 1 /1 0 0 0C·肉毒杀鼠素毒饵 ,以投饵量 1 .5~ 2 .2 5kg/hm2 ,采用机械间隔撒施法 ,不但能达到 90 %以上的灭鼠效果 ,而且能节约大量人力 ,降低灭治费用 ,提高工作效率  相似文献   
36.
AIM: To investigate the preventive effects of Clostridium butyricum (C. butyricum) on the type of pylorus ligated gastric ulcer (GU) in mice and the underlying mechanisms. METHODS: ICR mice were randomly divided into 4 groups: sham operation group, model group, C. butyricum pretreatment group and omeprazole pretreatment group. Gastric pyloric ligation was adopted to establish GU model in mice. The gastric juice was collected to measure the content of gastric free mucus, the pH of gastric juice and the activity of pepsin. The gastric tissues were collected for routine HE staining to observe the pathological changes. The content of glycogen was detected by PAS staining. The protein expression of Bax and Bcl-2 in the gastric mucosa was also assessed by immunohistochemical staining. RESULTS: The HE and PAS staining showed that the C. butyricum pretreatment obviously attenuated the mucosa lesion induced by ligation. Compared with model group, the pH of gastric juice was significantly raised. The activity of pepsin fell off in C. butyricum group, which was lower than that in omeprazole group. In comparison with model group, the content of gastric free mucus was dramatically increased and PAS staining showed a significant rise in C. butyricum group, but not in omeprazole group. The protein expression of Bax was decreased and the protein expression of Bcl-2 was upgraded in C. butyricum group than those in model group. CONCLUSION: C. butyricum protects gastric mucosa against the challenge of pylorus ligation in mice and its mechanism may be related to inhibiting gastric acid secretion and the activation of pepsin, increasing the production of gastric free mucus, strengthening the expression of bcl-2 gene and inhibiting the expression of bax gene.  相似文献   
37.
INTODUCTION: Anaesthesia in lambs undergoing experimental surgery may develop problems associated with age-related immune incompetency: a postoperative complication in a 3 week old Scottish blackface lamb after spinal surgery is presented. CASE HISTORY AND MANAGEMENT: Both lamb and ewe were in good condition. The ewe was vaccinated against Clostridium perfringens and Clostridium tetani 5 weeks pre-partum. There were no apparent problems with the lamb's intake of colostrum. Pre-anaesthetic medication was intramuscular medetomidine (10 μg kg(-1)). Anaesthesia was induced and maintained with sevoflurane in oxygen. Morphine (0.5 mg kg(-1)), meloxicam (0.6 mg kg(-1)) and ketamine (1 mg kg(-1) followed by 10 μg kg(-1) minute(-1)) were administered intravenously (IV) for perioperative analgesia. Atracurium (0.5 mg kg(-1) IV, followed by 0.17 mg kg(-1) injected when the first twitch of the four, train-of four count was palpated) was used to improve muscle relaxation. The lamb's trachea was intubated and the lungs mechanically ventilated to maintain normocapnia. Intrathecal morphine (0.2 mg kg(-1)), IV meloxicam (0.3 mg kg(-1)) and edrophonium (0.5 mg kg(-1)) were administered before recovery. Operative and initial recovery periods were unremarkable. Three hours after surgery the lamb became depressed. Tachycardia (180-250 beats minute(-1)), tachypnoea (30 breaths minute(-1)), poor peripheral perfusion and cold pelvic limb extremities were present mimicking severe pain, and/or hypovolaemic shock. Analgesics - morphine (total dose 1.3 mg kg(-1)) - and IV fluid therapy boluses - crystalloids (300 mL), colloids (120 mL) and fresh whole blood (60 mL) - failed to ameliorate clinical signs and so the lamb was euthanized 10 hours after surgery. Post-mortem findings supported a possible diagnosis of peracute Clostridium perfringens enterotoxaemia. CONCLUSION: Clostridium perfringens enterotoxaemia should be considered when clinical signs of severe pain and/or hypovolaemic shock fail to respond to analgesics and fluid resuscitation in lambs after major surgery.  相似文献   
38.
应用溶血试验和动物试验方法,检测来源于正常羊肠内容物和猝死羊肝、脾及肠内容物中产气荚膜杆菌及其毒素的溶血性和致病性。结果显示,在1%葡萄糖血平板上,所有14株猝死羊分离株均表现出典型的双溶血环(100%),而在22株正常羊分离株中5株为双溶血环(22.7%)、15株为单溶血环(68.2%)和2株不溶血(9.1%);对1%绵羊红细胞的溶血作用上,猝死羊分离株毒素的溶血OD50值多在0.40~0.90,而正常羊分离株毒素的OD50值多在0.40以下:所有分离株及其毒素对小白鼠的致死性无显著差异。  相似文献   
39.
ELISA对动物舍气载魏氏梭菌型别的研究   总被引:4,自引:1,他引:3  
采用ELISA方法对从一个犊牛舍空气中分离到的魏氏梭菌进行型别的鉴定。结果显示:88%的菌种属于A型,3.4%为C型,8.6%是D型,B型未能确认。  相似文献   
40.
试验证明用单一菌株C59-2生产C型产气荚膜梭菌肠毒血症干粉灭活疫苗,其效力可以达到《规程》要求,并且简化了生产工艺,降低了生产成本,提高了生产效率。疫苗免疫的兔血清可分别中和原来3个制苗用菌株所产生的外毒素。  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