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   407篇
  免费   25篇
  国内免费   1篇
耳鼻咽喉   4篇
儿科学   22篇
妇产科学   4篇
基础医学   60篇
口腔科学   7篇
临床医学   45篇
内科学   76篇
皮肤病学   10篇
神经病学   8篇
特种医学   127篇
外科学   6篇
综合类   13篇
预防医学   19篇
眼科学   4篇
药学   22篇
  1篇
肿瘤学   5篇
  2021年   6篇
  2018年   5篇
  2016年   12篇
  2015年   16篇
  2014年   8篇
  2013年   7篇
  2012年   15篇
  2011年   14篇
  2010年   10篇
  2009年   11篇
  2008年   14篇
  2007年   8篇
  2006年   6篇
  2005年   6篇
  2004年   5篇
  2003年   4篇
  2002年   4篇
  2001年   3篇
  2000年   2篇
  1999年   5篇
  1998年   17篇
  1997年   22篇
  1996年   21篇
  1995年   19篇
  1994年   14篇
  1993年   14篇
  1992年   7篇
  1991年   10篇
  1990年   10篇
  1989年   16篇
  1988年   20篇
  1987年   15篇
  1986年   11篇
  1985年   12篇
  1984年   3篇
  1982年   2篇
  1981年   7篇
  1979年   2篇
  1978年   6篇
  1968年   2篇
  1967年   4篇
  1966年   2篇
  1964年   2篇
  1961年   2篇
  1959年   4篇
  1958年   4篇
  1957年   3篇
  1956年   4篇
  1955年   2篇
  1954年   3篇
排序方式: 共有433条查询结果,搜索用时 15 毫秒
1.

Introduction The focus in clinical pharmacy practice is and has for the last 30–35 years been on changing the role of pharmacy staff into service orientation and patient counselling. One way of doing this is by involving staff in change process and as a researcher to take part in the change process by establishing partnerships with staff. On the background of the authors’ widespread action research (AR)-based experiences, recommendations and comments for how to conduct an AR-study is described, and one of their AR-based studies illustrate the methodology and the research methods used. Methodology AR is defined as an approach to research which is based on a problem-solving relationship between researchers and clients, which aims at both solving a problem and at collaboratively generating new knowledge. Research questions relevant in AR-studies are: what was the working process in this change oriented study? What learning and/or changes took place? What challenges/pitfalls had to be overcome? What were the influence/consequences for the involved parts? When to use If you want to implement new services and want to involve staff and others in the process, an AR methodology is very suitable. The basic advantages of doing AR-based studies are grounded in their participatory and democratic basis and their starting point in problems experienced in practice. Limitations Some of the limitations in AR-studies are that neither of the participants in a project steering group are the only ones to decide. Furthermore, the collective process makes the decision-making procedures relatively complex.

  相似文献   
2.
The aim of our study was to analyze circadian distribution of premature ventricular contractions (PVC) and its coupling interval (CI) in patients after orthotopic heart transplantation (HTx). Forty-two patients (5 females, 37 males) were monitored from 2 weeks to 5 years after HTx; 180 24-hour Holter ECG studies were performed. All recordings were divided into two groups: group I, within 1 month after HTX; and group II, after 1 month. Patients with more than 250 PVC/24 hours were selected for distribution of PVC and CI evaluation. Conclusions : Ventricular arrhythmias occur frequently in patients after heart transplantation. In patients with high Lown scale arrhythmias low occurrence (< 250/24 hours) of PVC was frequently observed (IVa: 81.8%; IVb: 84.7%). Similar patterns of circadian distribution (CD) of PVC and CD of HR in denervated heart after HTx suggest the influence of circulating catecholamines on their occurrence.  相似文献   
3.
4.
5.
The 13th edition of the standards of the American Association of Blood Banks specified storage at 1 to 6 degrees C for cryoprecipitated anti-hemophilic factor (Cryo) administered up to 6 hours after thawing if the Cryo is used for factor VIII (FVIII) content (Standard J4.210). Previous editions specified room-temperature (RT) storage for up to 6 hours. Currently, the temperature specification has been deleted. There are few data addressing the optimal storage temperature and maximum storage time for FVIII and fibrinogen in thawed Cryo. Thirty bags of Cryo were assayed for FVIII and fibrinogen. Each bag was divided into two aliquots; one was stored at RT and the other at 1 to 6 degrees C. Assays were performed immediately after thawing (Base) and 6 and 24 hours after thawing, respectively. All samples were filtered through 200-mu blood component infusion sets before assay. Three hundred analyses were performed, 150 each for FVIII and fibrinogen by conventional clotting technique. Data were analyzed by using a paired t test. Cryo stored at 1 to 6 degrees C for 6 and 24 hours showed an FVIII loss of 35 percent (p less than 0.0001) and 63 percent (p less than 0.0001), respectively. Cryo stored at RT for 6 and 24 hours had an FVIII loss of 8 percent (p greater than 0.05) and 20 percent (p less than 0.0001). Cryo stored at 1 to 6 degrees C for 6 and 24 hours had a fibrinogen loss of 20 percent (p less than 0.0001) and 43 percent (p less than 0.0001). Cryo stored at RT for 6 hours had no fibrinogen loss and a 2 percent loss at 24 hours (p greater than 0.05). These preliminary data show a significant loss of FVIII and fibrinogen activity in Cryo stored at 1 to 6 degrees C and filtered before assay. The FVIII and fibrinogen activity at RT is clearly maintained up to 6 hours after thawing.  相似文献   
6.
7.
Freeman  SD; Kelm  S; Barber  EK; Crocker  PR 《Blood》1995,85(8):2005-2012
CD33 is a member of the Ig superfamily that is restricted to cells of the myelomonocytic lineage but whose functions and binding properties are unknown. It shares sequence similarity with sialoadhesin, CD22, and the myelin-associated glycoprotein, which constitute the Sialoadhesin family of sialic acid-dependent cell adhesion molecules. In the present study, we show that CD33 is a fourth member of this family. As a model for sialic acid-dependent binding, human erythrocytes were derivatized with N-acetylneuraminic acid (NeuAc) in different linkages. A recombinant soluble form of CD33, Fc-CD33, bound red blood cells with a specificity similar to that of sialoadhesin, preferring NeuAc alpha 2,3Gal in N- and O-glycans over NeuAc alpha 2,6Gal in N-glycans. Fc- CD33 also bound selectively to the myeloid cell lines HL-60 and U937. However, CD33 was unable to mediate cell binding after transient expression in COS cells, despite high levels of surface expression. Pretreatment of the CD33-transfected cells with sialidase rendered them capable of mediating sialic acid-dependent binding. These results show that CD33 can function as a sialic acid-dependent cell adhesion molecule and that binding can be modulated by endogenous sialoglycoconjugates when CD33 is expressed in a plasma membrane.  相似文献   
8.
9.
Three patients with primary neuropathic amyloidosis are reported. They were all almost totally disabled by either diarrhea and incontinentia alvi or obstipation. In all three patients enterostomies were tried as a palliative treatment and the results of the operations have been very promising.  相似文献   
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