首页 | 官方网站   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   2235篇
  免费   215篇
  国内免费   17篇
医药卫生   2467篇
  2021年   23篇
  2019年   25篇
  2018年   35篇
  2017年   23篇
  2016年   24篇
  2015年   34篇
  2014年   20篇
  2013年   75篇
  2012年   75篇
  2011年   72篇
  2010年   56篇
  2009年   64篇
  2008年   73篇
  2007年   78篇
  2006年   78篇
  2005年   83篇
  2004年   62篇
  2003年   62篇
  2002年   63篇
  2001年   54篇
  2000年   44篇
  1999年   51篇
  1998年   59篇
  1997年   52篇
  1996年   56篇
  1995年   30篇
  1994年   53篇
  1993年   40篇
  1992年   41篇
  1991年   44篇
  1990年   44篇
  1989年   61篇
  1988年   56篇
  1987年   58篇
  1986年   64篇
  1985年   45篇
  1984年   40篇
  1983年   33篇
  1982年   27篇
  1981年   37篇
  1980年   26篇
  1979年   57篇
  1978年   48篇
  1977年   42篇
  1976年   31篇
  1975年   26篇
  1973年   29篇
  1972年   23篇
  1970年   19篇
  1969年   23篇
排序方式: 共有2467条查询结果,搜索用时 0 毫秒
1.
Intravenous administration of high-dose pentobarbital has been proposed as a treatment for elevated intracranial pressure refractory to other measures in brain-injured patients. The purpose of this clinical study was to examine the pharmacokinetics of high-dose continuous intravenous infusion of pentobarbital in this critical care setting. Six patients received a 25-34 mg/kg intravenous loading dose followed by a 1-3 mg/kg/h continuous infusion for 61-190 hours. Dosing rates were adjusted based on the patient's clinical status. The mean clearance was 0.72 ml/min/kg, with a volume of distribution (Vd) of 1.03 L/kg and a terminal half-life of 19.1 h. Considerable variation in individual patient parameters was observed. In addition, a change in clearance was suggested in patients requiring a longer infusion duration.  相似文献   
2.
3.
H Kikuta  F Rapp 《Intervirology》1988,29(5):281-291
We examined the effect of infection by other herpesviruses on the induction of Epstein-Barr virus (EBV) antigens. Raji cells were infected with a variety of viruses before superinfection with P3HR-1 virus 6 h later. Much earlier and greater synthesis of EBV antigens was observed in herpesvirus (herpes simplex virus type 1, type 2 and pseudorabies virus)-infected Raji cells than in mock-infected Raji cells prior to superinfection with P3HR-1 virus, as determined by indirect immunofluorescence tests or immunoprecipitation and PAGE. Although infection with a temperature-sensitive mutant of pseudorabies virus (tsG1) enhanced EBV antigen synthesis as well as wild-type pseudorabies virus at permissive temperature in Raji cells superinfected with P3HR-1 virus, EBV antigen synthesis was strongly inhibited at temperatures nonpermissive for tsG1. These results suggest that a herpesvirus immediate-early protein may play a role in enhancement of EBV antigen expression.  相似文献   
4.
Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
  相似文献   
5.
Measuring patient outcomes is important to rehabilitation nurses and the patients they serve. This article describes research conducted at the University of Iowa College of Nursing to develop the Nursing Outcomes Classification (NOC) and the validation of this research by surveys conducted through specialty nursing organizations, particularly the Association of Rehabilitation Nurses. Nurses responded to surveys designed to validate (a) the importance of outcome indicators to the achievement of an outcome and (b) nursing's contribution to the achievement of the indicators. The results of the surveys indicated that rehabilitation nurses believe that nursing makes a substantial contribution to most outcomes and indicators.  相似文献   
6.
7.
Summary In this report we describe changes in the intracellular redistribution of raf serine/threonine protein kinase (product of the raf proto-oncogene family) in hippocampal neurons following cerebral ischemia in Mongolian gerbils. For immunohistochemical localization studies polyclonal antisera specific for each of the A, B, and Raf-1 isotypes of raf, as well as a pan-raf antisera, were employed. Of these, only sera recognizing B-raf, as well as the general v-raf (raised against the conserved C-terminal region) were positive, indicating that B-raf is the major isotype in this neuronal region. Three different ischemie models were used (repeated 3 times for two min and single 5 or 15 min occlusions, of the common carotid arteries) to demonstrate that ischemie insult causes redistribution of raf protein kinase into the cell nucleus of hippocampal neurons. Increased amounts of raf protein in the nuclei of pyramidal cells following ischemia was confirmed by Western blot analysis of isolated nuclear fractionations. Moreover, an elevation in the level of nuclear raf protein also was detected in the contralateral (i.e. non-occluded hemisphere) neurons of CA1 and CA3 subfields 4 days after the ischemie insult indicating a possible transsynaptic increase in the amount of raf protein along with redistribution. The intranuclear translocation of the immunoreactive material started from the perinucleolar rim and with time extended throughout the nucleus. Enhanced levels and altered redistribution of the raf polypeptide in the nuclei of pyramidal cells of the CA3 subfleld appears to be reversible and returns to the normal level 12 days following the ischemic insult. In addition to triggering the above changes in the intracellular redistribution of raf, ischemie insult also caused an increase in the level of B-raf protein in reactive astrocytes.  相似文献   
8.

Background

Intensivists must provide enough analgesia and sedation to ensure dying patients receive good palliative care. However, if it is perceived that too much is given, they risk prosecution for committing euthanasia. The goal of this study is to develop consensus guidelines on analgesia and sedation in dying intensive care unit patients that help distinguish palliative care from euthanasia.

Methods

Using the Delphi technique, panelists rated levels of agreement with statements describing how analgesics and sedatives should be given to dying ICU patients and how palliative care should be distinguished from euthanasia. Participants were drawn from 3 panels: 1) Canadian Academic Adult Intensive Care Fellowship program directors and Intensive Care division chiefs (N = 9); 2) Deputy chief provincial coroners (N = 5); 3) Validation panel of Intensivists attending the Canadian Critical Care Trials Group meeting (N = 12).

Results

After three Delphi rounds, consensus was achieved on 16 statements encompassing the role of palliative care in the intensive care unit, the management of pain and suffering, current areas of controversy, and ways of improving palliative care in the ICU.

Conclusion

Consensus guidelines were developed to guide the administration of analgesics and sedatives to dying ICU patients and to help distinguish palliative care from euthanasia.  相似文献   
9.
10.
Clonal diversity in Haemophilus pleuropneumoniae.   总被引:7,自引:3,他引:7       下载免费PDF全文
Genetic diversity among 135 isolates of nine serotypes of Haemophilus pleuropneumoniae recovered from pigs with pleuropneumonia or other invasive diseases in 14 countries was estimated by multilocus enzyme electrophoresis, which detects allelic variation in structural genes. Thirty-two multilocus genotypes (electrophoretic types [ETs]) were distinguished on the basis of allele profiles at 15 enzyme loci, and 36 distinctive combinations of ET and serotype were identified. The recovery of isolates with identical properties in widely separated geographic regions and over a 20-year period indicated that the population structure of H. pleuropneumoniae is clonal. Isolates of the same ET generally shared the same serotype and electrophoretic pattern of the outer membrane proteins, but some ETs were represented by isolates of several different serotypes, outer membrane protein patterns, or both. On average, the genetic diversity among ETs of the same serotype was 56% of the total genetic diversity in the species. Isolates of serotype 1, which are unusually pathogenic, belong to a distinctive group of clones that are closely related to clones marked by serotype 9.  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-23

京公网安备 11010802026262号