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   1482篇
  免费   97篇
  国内免费   22篇
耳鼻咽喉   4篇
儿科学   54篇
妇产科学   18篇
基础医学   116篇
口腔科学   19篇
临床医学   166篇
内科学   462篇
皮肤病学   228篇
神经病学   45篇
特种医学   127篇
外科学   106篇
综合类   15篇
预防医学   144篇
药学   67篇
肿瘤学   30篇
  2021年   7篇
  2019年   9篇
  2018年   10篇
  2017年   15篇
  2016年   33篇
  2015年   41篇
  2014年   38篇
  2013年   70篇
  2012年   26篇
  2011年   37篇
  2010年   43篇
  2009年   58篇
  2008年   29篇
  2007年   31篇
  2006年   38篇
  2005年   22篇
  2004年   22篇
  2003年   23篇
  2002年   23篇
  2001年   14篇
  2000年   24篇
  1999年   49篇
  1998年   69篇
  1997年   56篇
  1996年   60篇
  1995年   51篇
  1994年   58篇
  1993年   39篇
  1992年   58篇
  1991年   16篇
  1990年   44篇
  1989年   45篇
  1988年   56篇
  1987年   35篇
  1986年   28篇
  1985年   13篇
  1984年   36篇
  1983年   17篇
  1982年   20篇
  1981年   23篇
  1980年   17篇
  1978年   11篇
  1977年   9篇
  1976年   13篇
  1975年   8篇
  1973年   9篇
  1972年   7篇
  1971年   9篇
  1966年   9篇
  1964年   14篇
排序方式: 共有1601条查询结果,搜索用时 15 毫秒
51.
52.
ObjectivesHamstring injuries are common among soccer players. The hamstring outcome score (HaOS) might be useful to identify amateur players at risk of hamstring injury. Therefore the aims of this study were: To determine the association between the HaOS and prior and new hamstring injuries in amateur soccer players, and to determine the prognostic value of the HaOS for identifying players with or without previous hamstring injuries at risk of future injury.DesignCohort study.MethodsHaOS scores and information about previous injuries were collected at baseline and new injuries were prospectively registered during a cluster-randomized controlled trial involving 400 amateur soccer players. Analysis of variance and t-tests were used to determine the association between the HaOS and previous and new hamstring injury, respectively. Logistic regression analysis indicated the prognostic value of the HaOS for predicting new hamstring injuries.ResultsAnalysis of data of 356 players indicated that lower HaOS scores were associated with more previous hamstring injuries (F = 17.4; p = 0.000) and that players with lower HaOS scores sustained more new hamstring injuries (T = 3.59, df = 67.23, p = 0.001). With a conventional HaOS score cut-off of 80%, logistic regression models yielded a probability of hamstring injuries of 11%, 18%, and 28% for players with 0,1, or 2 hamstring injuries in the previous season, respectively.ConclusionsThe HaOS is associated with previous and future hamstring injury and might be a useful tool to provide players with insight into their risk of sustaining a new hamstring injury risk when used in combination with previous injuries.  相似文献   
53.
McColl  SR; Kreis  C; DiPersio  JF; Borgeat  P; Naccache  PH 《Blood》1989,73(2):588-591
Pre-incubation of human neutrophils with pertussis toxin significantly inhibited the neutrophil-directed biologic actions of granulocyte- macrophage colony-stimulating factor (GM-CSF) in three separate assays: the induction of c-fos mRNA, the enhancement of both platelet- activating factor-induced mobilization of intracellular calcium, and stimulation of leukotriene synthesis by the calcium ionophore A23187. Cholera toxin did not have an effect on the latter two assays. Pre- treatment of human neutrophils with pertussis toxin did not affect the binding of GM-CSF to its surface receptor. These results provide the first evidence that a pertussis toxin substrate plays an important mediatory role in the mechanism of action of GM-CSF.  相似文献   
54.
55.
56.
57.
58.
Ultrasound‐guided fine needle aspiration (USG‐FNA) has enabled cytopathologists to accurately diagnose smaller or non‐palpable lymph nodes (LN) on a regular basis. Pre‐FNA clinical and ultrasonographic factors, such as a patient's age, ratio of short to long axis diameter (S/L ratio), internal echogenicity, and the vascular pattern of a LN, are reported to be able to predict the benign or malignant nature of a LN. This study is designed to test the formula “0.06 × (age) + 4.76 × (S/L ratio) + 2.15 × (internal echo) + 1.80 × (vascular pattern)” generated from the study of Liao et al. as a scoring system for predicting LN malignancy in a cytopathologist operated USG‐FNA practice. Eighty‐three reports of USG‐FNA of LNs issued between 7/1/2008 and 4/28/2010 were reviewed. Patient's age, S/L ratio, internal echo, and vascular pattern were used to generate scores based on the aforementioned formula. A score of seven was used as a cutoff for predicting benign (<7) and malignant (>7) LNs. FNA cytology diagnosis, flow cytometric analysis as well as subsequent surgical diagnosis in some cases served as gold standard for statistical analysis. Among 46 USG‐FNA of LNs with scores > 7, 38 were malignant and eight were benign. All 37 USG‐FNA of LNs with scores < 7 were proven to be benign. The scoring system achieved 100% sensitivity, 82% specificity, 83% positive predictive value, 100% negative predictive value, and 90% accuracy. Further study of the eight “false‐positive” cases revealed that three of them (37.5%) were found to be malignant in follow‐up FNA and/or surgical biopsy. This scoring system may serve as a complementary tool in determining how aggressive a FNA procedure should be performed, how a FNA sample of LN should be triaged for ancillary study, and how closely a patient with lymphadenopathy should be followed up. Diagn. Cytopathol. 2013;41:1100–1106. © 2011 Wiley Periodicals, Inc.  相似文献   
59.
60.
The object of this study was to compare the outcomes of the vacuum assisted closure (VAC) therapy and conventional wound care with dressing change for treatment of complex wounds in patients with replantation of amputated upper and lower extremities. Data of 43 patients with replantation of amputated extremities from May 2004 to December 2011 were reviewed. There were 18 wounds of 18 patients with replantation, which were treated by dressing change and 26 wounds of 25 patients by VAC therapy. The outcomes were evaluated by the survival rate of replanted extremities, growth of granulation tissue, interval between wound treatment and secondary procedure and eventual secondary wound coverage methods. Vascular thromboses were found in 3 patients with wound treatment by dressing change and 5 by VAC. All replants of two groups of patients survived after salvage procedures. The wound score was 3.6 ± 0.7 in the conventional dressing change group and 5.8 ± 0.7 in the VAC group at the sixth day after treatment, respectively. The intervals between wound treatment and secondary wound coverage procedure were 12.0 ± 1.7 days in the dressing change group and 6.1 ± 0.7 days in the VAC group. Flaps were applied for wound coverage in 9 out of 18 (50.0%) wounds in the dressing change group and 5 out of 26 (19.2%) in the VAC group (P < 0.05), when the wounds of rest of patients were covered by the skin graft. The results showed that VAC could promote the growth of granulation tissue of wound, decrease the need of flap for wound coverage, and did not change the survival of replantation. © 2013 Wiley Periodicals, Inc. Microsurgery 33:620–624, 2013.  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