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   4629篇
  免费   311篇
  2023年   21篇
  2022年   22篇
  2021年   95篇
  2020年   50篇
  2019年   83篇
  2018年   94篇
  2017年   89篇
  2016年   123篇
  2015年   189篇
  2014年   226篇
  2013年   321篇
  2012年   428篇
  2011年   368篇
  2010年   230篇
  2009年   194篇
  2008年   316篇
  2007年   293篇
  2006年   292篇
  2005年   247篇
  2004年   254篇
  2003年   233篇
  2002年   176篇
  2001年   49篇
  2000年   35篇
  1999年   36篇
  1998年   58篇
  1997年   38篇
  1996年   51篇
  1995年   34篇
  1994年   26篇
  1993年   23篇
  1992年   26篇
  1991年   28篇
  1990年   13篇
  1989年   15篇
  1988年   11篇
  1987年   7篇
  1986年   11篇
  1985年   14篇
  1984年   14篇
  1983年   10篇
  1982年   19篇
  1981年   10篇
  1980年   9篇
  1979年   9篇
  1978年   10篇
  1974年   5篇
  1973年   4篇
  1971年   4篇
  1941年   4篇
排序方式: 共有4940条查询结果,搜索用时 31 毫秒
81.
82.
Babesia caballi and Theileria equi are widely recognized as causative agents of equine pirolasmosis (EP), an acute, sub‐acute, and chronic disease of equines, with relevant economic impact on horse trade worldwide. Although several studies on EP prevalence from central Italy have been published, data on ticks responsible for its transmission are still lacking. In this study, we identified a potential competent vector, investigating main features of its ecology together with EP infection rates. A two‐year sampling of questing ticks was carried out for the first time in Italy in an area known for high EP prevalence in horse sera, detecting the association between Rhipicephalus bursa and causative agents of EP. Most of the positive pools harbored a single infection (91.1%); mixed infections were also detected (8.9%). The infection rate for T. equi slightly decreased among years; B. caballi showed a lower, but increasing, infection rate. Tick phenology, climate variables, and peaks of EP prevalence indicated late May and second half of June as periods with the highest risk of new infections, especially during warm and dry days.  相似文献   
83.
84.
Probiotics and Antimicrobial Proteins - This study aimed to characterize, evaluate toxicity and optimize the conditions for the growth and production of bacteriocin-like substances by Lactobacillus...  相似文献   
85.
86.
87.
Experimental and Applied Acarology - In total, 57 ticks were collected from six white-tailed deer (Odocoileus virginianus) and three mule deer (O. hemionus) in northern Mexico during the 2017, 2018...  相似文献   
88.
Coral Reefs - Scleractinian corals feature both sessile and mobile stages and diverse modes of development. In some cases, development can be reversed. Examples include polyp detachment in response...  相似文献   
89.
90.
Virus detection methods are important to cope with the SARS-CoV-2 pandemics. Apart from the lung, SARS-CoV-2 was detected in multiple organs in severe cases. Less is known on organ tropism in patients developing mild or no symptoms, and some of such patients might be missed in symptom-indicated swab testing. Here, we tested and validated several approaches and selected the most reliable RT-PCR protocol for the detection of SARS-CoV-2 RNA in patients’ routine diagnostic formalin-fixed and paraffin-embedded (FFPE) specimens available in pathology, to assess (i) organ tropism in samples from COVID-19-positive patients, (ii) unrecognized cases in selected tissues from negative or not-tested patients during a pandemic peak, and (iii) retrospectively, pre-pandemic lung samples. We identified SARS-CoV-2 RNA in seven samples from confirmed COVID-19 patients, in two gastric biopsies, one small bowel and one colon resection, one lung biopsy, one pleural resection and one pleural effusion specimen, while all other specimens were negative. In the pandemic peak cohort, we identified one previously unrecognized COVID-19 case in tonsillectomy samples. All pre-pandemic lung samples were negative. In conclusion, SARS-CoV-2 RNA detection in FFPE pathology specimens can potentially improve surveillance of COVID-19, allow retrospective studies, and advance our understanding of SARS-CoV-2 organ tropism and effects.  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