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   110篇
  免费   18篇
  2022年   1篇
  2021年   5篇
  2017年   4篇
  2015年   3篇
  2014年   2篇
  2013年   5篇
  2012年   9篇
  2011年   7篇
  2010年   6篇
  2009年   12篇
  2008年   7篇
  2007年   5篇
  2006年   6篇
  2005年   4篇
  2004年   5篇
  2003年   3篇
  2002年   1篇
  2001年   2篇
  2000年   3篇
  1999年   6篇
  1998年   9篇
  1997年   2篇
  1996年   1篇
  1995年   2篇
  1993年   1篇
  1991年   2篇
  1990年   1篇
  1988年   2篇
  1986年   1篇
  1984年   1篇
  1982年   1篇
  1981年   3篇
  1979年   1篇
  1978年   2篇
  1968年   1篇
  1966年   1篇
  1965年   1篇
排序方式: 共有128条查询结果,搜索用时 46 毫秒
91.
Effects of dietary contamination with various levels of deoxynivalenol (DON) and zearalenone (ZEA) were investigated on Ross 308 hybrid broilers of both sexes. After hatching, all chickens were fed an identical control diet for two weeks. Then chickens of Group 1 received a diet contaminated with DON and ZEA, both being 3.4 mg kg(-1), while Group 2 received DON and ZEA at 8.2 and 8.3 mg kg(-1), respectively. The diet of the control group contained background levels of mycotoxins. Samples of blood and tissues were collected after two weeks. Intake of both contaminated diets resulted in a significantly decreased activity of glutathione peroxidase (GPx) and increased level of malondialdehyde (MDA) in liver tissue, while in kidneys the concentration of MDA was significantly increased only in Group 1. On the other hand, activities of blood GPx and plasma gamma-glutamyltransferase (GGT) were elevated in Group 2 only. Activities of thioredoxin reductase in liver and GPx in duodenal mucosa tissues, superoxide dismutase (SOD) in erythrocytes as well as levels of MDA in duodenal mucosa and alpha-tocopherol in plasma were not affected by dietary mycotoxins. Blood phagocytic activity was significantly depressed in Group 1 and 2. These results demonstrate that diets contaminated with DON and ZEA at medium levels are already able to induce oxidative stress and compromise the blood phagocytic activity in fattening chickens.  相似文献   
92.
Fourteen native strains of Trichoderma spp. from wildand agricultural pathosystems in the state of Yucatan, Mexico, with growth-promoting ability of Capsicum chinense Jacq. seedlings were evaluated and antagonistic effect of their filtrate against second-stage juveniles (J2) of Meloidogyne incognita. The strains Th05-02 and Th27-08 showed the best significant effects on plant hight variable increments 55.57 and 47.62%, theTh07-04 with 29.48% more root length, theTh02-01 and Th07-04 isolates increased from 48.71 to 84.61% in volume radical and 53.40% of total dry biomass. Statistical analysis (p≤0.001) of Th43 and Th43-13-14 filtrates caused 100% mortality at 24 and 48h. In the test of reversibility to 24 h after replacing the filtrates Th43-13, Th43-14, TH09-06 and TH20-07 by sterile distilled water, the J2 did not recover their viability, so they were considered as the best potential strains of Trichoderma spp. with antagonistic capacity in J2 of M.incognita.  相似文献   
93.
Between March 1987 and January 1998, 1127 patients with an oligospermia < millions/ml were followed up for infertility problems. 876 of these patients were followed up at least one year (mean: 3.2 years). During this period, each patient performed at least two spermograms with an interval varying from 6 months to 3 years. We studied the evolution of the quality of sperm during follow up and tried to show the pronostic factors of a potential decline We found an impairment of all the sperm quality parameters from the outset of the sixth month. At the fourth year of follow up more than 2/3 of the patients had a significant impairment of sperm quality and none of them showed any improvement. The % of sperm motility appears to be the most important prognostic factor in predicting an impairment. Sperm motility <20% predicts a significant impairment in sperm quality in the following two years.  相似文献   
94.
95.
96.
97.
98.
Pairwise likelihood methods for inference in image models   总被引:3,自引:0,他引:3  
Nott  DJ; Ryden  T 《Biometrika》1999,86(3):661-676
  相似文献   
99.
100.
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