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   223948篇
  免费   14984篇
  国内免费   49篇
  238981篇
  2021年   1773篇
  2018年   3125篇
  2017年   3023篇
  2016年   3666篇
  2015年   3201篇
  2014年   4437篇
  2013年   6321篇
  2012年   7542篇
  2011年   8060篇
  2010年   5721篇
  2009年   4876篇
  2008年   7197篇
  2007年   7477篇
  2006年   7178篇
  2005年   6703篇
  2004年   6848篇
  2003年   6567篇
  2002年   6524篇
  2001年   9274篇
  2000年   8953篇
  1999年   6987篇
  1998年   2122篇
  1997年   1953篇
  1996年   1819篇
  1992年   5467篇
  1991年   5677篇
  1990年   5650篇
  1989年   5620篇
  1988年   5212篇
  1987年   4862篇
  1986年   4442篇
  1985年   4677篇
  1984年   3696篇
  1983年   3025篇
  1982年   2013篇
  1981年   1722篇
  1980年   1725篇
  1979年   3338篇
  1978年   2576篇
  1977年   2375篇
  1976年   2330篇
  1975年   2826篇
  1974年   3117篇
  1973年   3084篇
  1972年   2746篇
  1971年   2604篇
  1970年   2212篇
  1969年   2158篇
  1968年   2031篇
  1967年   1797篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
901.
902.
903.
904.
905.
906.
The data presented in this work indicate that specific antisera to P. aeruginosa and Proteus antigens can be produced by using extracts from these microorganisms, destroyed by ultrasonic treatment or by multiple freezing and thawing, for the immunization of rabbits. Blood serum samples from patients with purulent septic complications were studied for the presence of P. aeruginosa and Proteus antigens in ELISA with the use of peroxidase-labeled antibodies from antisera to P. aeruginosa and Proteus. This investigation revealed that during the first 3 days from the beginning of the clinical manifestations of the complications P. aeruginosa and Proteus antigens were detected in 86.4% and 83.4% of the patients, respectively. In the subsequent bacteriological study of wound discharge from these patients the corresponding microflora was detected.  相似文献   
907.
908.
Clinical, bacteriological, serological and epidemiological studies of ozena morbidity among the population of Minsk were carried out in 1970-1980. On January 1, 1981, the ozena morbidity rate among the inhabitants of Minsk was 26.72%. Ozena was found to affect mainly children and women. A wide spread of the family foci of this disease (31.68%) was revealed. The results of this study indicate that the source of K. ozaenae is a sick person who begins to excrete the bacteria in the prodromal period of the disease and may continue to excrete them for many years. The transfer of K. ozaenae occurs probably by droplet or contact infection. The droplet infection is less active in the absence of symptoms (coughing, sneezing) facilitating excretion of the infective agent into the air and in cases of the low susceptibility of persons to ozena. The main measures for controlling ozena are the timely detection and sanitation of the sources of ozena, as well as the current disinfection of the infection foci in apartments.  相似文献   
909.
910.
The relationship between delayed hypersensitivity (DH) to S. aureus surface antigens and the intensity of the infectious process induced by the sublethal infection of guinea pigs with S. aureus was studied. The protective effect, manifested by a decrease in the staphylococcal contamination of the spleen tissue and by an increase in the level of the activation of lymphocytes, was shown to correlate with DH induced by inactivated staphylococcal cells. In infected guinea pigs having DH to different staphylococcal antigens the disease either took a more severe course (in cases of DH to cell wall or peptidoglycan) than in the animals subjected only to infection, or no aggravation of the disease was observed (in cases of DH to protein A).  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