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   44090篇
  免费   2633篇
  国内免费   200篇
耳鼻咽喉   155篇
儿科学   2656篇
妇产科学   1659篇
基础医学   2128篇
口腔科学   575篇
临床医学   2892篇
内科学   11334篇
皮肤病学   382篇
神经病学   1764篇
特种医学   895篇
外国民族医学   1篇
外科学   7416篇
综合类   3242篇
一般理论   1篇
预防医学   7396篇
眼科学   490篇
药学   1694篇
  8篇
中国医学   192篇
肿瘤学   2043篇
  2023年   583篇
  2022年   591篇
  2021年   1539篇
  2020年   1269篇
  2019年   4373篇
  2018年   3537篇
  2017年   1955篇
  2016年   987篇
  2015年   997篇
  2014年   2013篇
  2013年   2030篇
  2012年   1482篇
  2011年   1589篇
  2010年   1278篇
  2009年   1204篇
  2008年   1151篇
  2007年   1131篇
  2006年   983篇
  2005年   822篇
  2004年   743篇
  2003年   614篇
  2002年   485篇
  2001年   433篇
  2000年   325篇
  1999年   298篇
  1998年   263篇
  1997年   256篇
  1996年   189篇
  1995年   172篇
  1994年   158篇
  1993年   133篇
  1992年   118篇
  1991年   94篇
  1990年   82篇
  1989年   74篇
  1988年   82篇
  1986年   77篇
  1985年   1039篇
  1984年   1454篇
  1983年   1083篇
  1982年   1174篇
  1981年   1116篇
  1980年   965篇
  1979年   1078篇
  1978年   998篇
  1977年   693篇
  1976年   893篇
  1975年   791篇
  1974年   706篇
  1973年   738篇
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
1.
2.
3.
《Vaccine》2022,40(7):1001-1009
Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases.  相似文献   
4.
When hospitals first encountered coronavirus disease 2019 (COVID-19), there was a dearth of therapeutic options and nearly 1 in 3 patients died from the disease. By the summer of 2020, as deaths from the disease declined nationally, multiple single-center studies began to report declining mortality of patients with COVID-19. To evaluate the effect of COVID-19 on hospital-based mortality, we searched the Vizient Clinical Data Base for outcomes data from approximately 600 participating hospitals, including 130 academic medical centers, from January 2017 through December 2020. More than 32 million hospital admissions were included in the analysis. After an initial spike, mortality from COVID-19 declined in all regions of the country to under 10% by June 2020 and remained constant for the remainder of the year. Despite this, inpatient, all-cause mortality has increased since the beginning of the pandemic, even those without respiratory failure. Inpatient mortality has particularly increased in elderly patients and in those requiring intubation for respiratory failure. Since June 2020, COVID-19 kills one in every 10 patients admitted to the hospital with this diagnosis. The addition of this new disease has raised overall hospital mortality especially those who require intubation for respiratory failure.  相似文献   
5.
6.
《Immunity》2022,55(9):1594-1608.e6
  1. Download : Download high-res image (141KB)
  2. Download : Download full-size image
  相似文献   
7.
8.
The coronavirus disease 2019, which is caused by severe acute respiratory syndrome coronavirus 2, was first identified in December 2019 in Wuhan, China, and has since spread rapidly, evolving into a full-blown pandemic. We would like to report our experience after 1 year of this pandemic in the surgical service of a district hospital in Spain. There have been many changes (including new protocols) that our service and the hospital have undergone, to adapt to the new situation. We believe that this experience can be useful for other professionals who have lived and are living a similar situation.  相似文献   
9.
10.
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