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   2153篇
  免费   151篇
  国内免费   25篇
耳鼻咽喉   8篇
儿科学   171篇
妇产科学   23篇
基础医学   235篇
口腔科学   52篇
临床医学   232篇
内科学   462篇
皮肤病学   26篇
神经病学   113篇
特种医学   500篇
外科学   155篇
综合类   43篇
一般理论   1篇
预防医学   85篇
眼科学   17篇
药学   114篇
中国医学   3篇
肿瘤学   89篇
  2022年   7篇
  2021年   11篇
  2020年   13篇
  2019年   16篇
  2018年   31篇
  2017年   22篇
  2016年   28篇
  2015年   37篇
  2014年   39篇
  2013年   78篇
  2012年   52篇
  2011年   45篇
  2010年   90篇
  2009年   72篇
  2008年   49篇
  2007年   52篇
  2006年   53篇
  2005年   42篇
  2004年   47篇
  2003年   38篇
  2002年   40篇
  2001年   33篇
  2000年   48篇
  1999年   42篇
  1998年   139篇
  1997年   121篇
  1996年   131篇
  1995年   96篇
  1994年   76篇
  1993年   87篇
  1992年   32篇
  1991年   31篇
  1990年   31篇
  1989年   67篇
  1988年   51篇
  1987年   56篇
  1986年   50篇
  1985年   50篇
  1984年   31篇
  1983年   34篇
  1982年   37篇
  1981年   21篇
  1980年   41篇
  1979年   20篇
  1978年   26篇
  1977年   22篇
  1976年   26篇
  1975年   29篇
  1973年   5篇
  1971年   7篇
排序方式: 共有2329条查询结果,搜索用时 31 毫秒
1.
There is a broad differential for patients presenting with fever, eosinophilia, and pneumonia. We present a case of a 48-year-old man who presented with recurrent fever, pleuritic chest pain, and cough. His medical history was significant for a recent trip to Arizona. A chest X ray showed a right lower lobe infiltrate and CT examination of the chest showed extensive mediastinal lymphadenopathy. Tissue culture from a biopsy specimen of the mediastinal lymph nodes revealed growth of Coccidioides immitis and a diagnosis of coccidioidomycosis was made. He was treated with a total of a 9-month course of itraconazole and has remained disease free for >2 years. This case shows how a careful history and evaluation will direct the clinician to the correct diagnosis.  相似文献   
2.
3.
BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
4.
5.
6.
Evaluation of an on-line patient exposure meter in neuroradiology   总被引:1,自引:0,他引:1  
  相似文献   
7.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
  相似文献   
8.
9.
Ghosts     
Ives  Samuel T. 《JAMA》2007,298(11):1259
  相似文献   
10.
We performed multidirectional chromosome painting in a comparative cytogenetic study of the three howler monkey species Alouatta fusca, A. caraya and A. seniculus macconnelli (Atelinae, Platyrrhini) in order to reconstruct phylogenetic relationships within this genus. Comparative genome maps between these species were established by multicolor fluorescence in-situ hybridization (FISH) employing human, Saguinus oedipus and Lagothrix lagothricha chromosome-specific probes. The three species included in this study and previously analyzed howler monkey species were subjected to a phylogenetic analysis on the basis of a data matrix comprised of 98 discrete molecular cytogenetic characters. The results revealed that howler monkeys represent the genus with the most extensive karyotype diversity within Platyrrhini so far analyzed with high levels of intraspecific chromosomal variability. Two different multiple sex chromosome systems were identified. The phylogenetic analysis indicated that Alouatta is a monophyletic clade which can be derived from a proposed ancestral Atelinae karyotype of 2n=62 chromosomes by a chromosome fusion, a fission, a Y-autosomal translocation and a pericentric inversion. Following these suggestions, the genus Alouatta can be divided into two distinct species groups: the first includes A. caraya and A. belzebul, the second A. s. macconnelli, A. sara, A. s. arctoidea and A. fusca.  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