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   3012篇
  免费   344篇
  国内免费   27篇
耳鼻咽喉   24篇
儿科学   96篇
妇产科学   113篇
基础医学   274篇
口腔科学   126篇
临床医学   364篇
内科学   780篇
皮肤病学   82篇
神经病学   156篇
特种医学   323篇
外科学   256篇
综合类   56篇
预防医学   423篇
眼科学   41篇
药学   91篇
中国医学   2篇
肿瘤学   176篇
  2023年   58篇
  2022年   34篇
  2021年   47篇
  2020年   65篇
  2019年   50篇
  2018年   87篇
  2017年   67篇
  2016年   75篇
  2015年   93篇
  2014年   143篇
  2013年   173篇
  2012年   116篇
  2011年   139篇
  2010年   106篇
  2009年   120篇
  2008年   114篇
  2007年   134篇
  2006年   118篇
  2005年   95篇
  2004年   96篇
  2003年   56篇
  2002年   67篇
  2001年   66篇
  2000年   79篇
  1999年   65篇
  1998年   81篇
  1997年   103篇
  1996年   88篇
  1995年   63篇
  1994年   72篇
  1993年   57篇
  1992年   47篇
  1991年   32篇
  1990年   54篇
  1989年   67篇
  1988年   48篇
  1987年   51篇
  1986年   48篇
  1985年   44篇
  1984年   20篇
  1983年   26篇
  1982年   25篇
  1981年   39篇
  1980年   24篇
  1979年   14篇
  1978年   10篇
  1977年   14篇
  1976年   16篇
  1975年   13篇
  1971年   11篇
排序方式: 共有3383条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
OBJECTIVE: To identify predictors and outcomes associated with frequent emergency department (ED) users. METHODS: Cross-sectional intake surveys, medical chart reviews, and telephone follow-up interviews of patients presenting with selected chief complaints were performed at five urban EDs during a one-month study period in 1995. Frequent use was defined by four or more self-reported, prior ED visits. Multivariate logistic regression identified predictors of frequent ED visitors from five domains (demographics, health status, health access, health care preference, and severity of acute illness). Associations between high use and selected outcomes were assessed with logistic regression models. RESULTS: All study components were completed by 2,333 of 3,455 eligible patients (67.5%). Demographics predicting frequent use included being a single parent, single or divorced marital status, high school education or less, and income of less than $10,000 (1995). Health status predictors included hospitalization in the preceding three months, high ratings of psychological distress, and asthma. Health access predictors included identifying an ED or a hospital clinic as the primary care site, having a primary care physician (PCP), and visiting a PCP in the past month. Choosing the ED for free care was the only health preference predictive of heavy use. Illness severity measures were higher in frequent visitors, although these were not independently predictive in the multivariate model. Outcomes correlated with heavy use include increased hospital admissions, higher rates of ED return visits, and lower patient satisfaction, but not willingness to return to the ED or follow-up with a doctor. CONCLUSIONS: Frequent ED visits are associated with socioeconomic distress, chronic illness, and high use of other health resources. Efforts to reduce ED visits require addressing the unique needs of these patients in the emergency and primary care settings.  相似文献   
95.
To investigate the frequency, course, and clinical correlates of disorientation following stroke, we administered the Mini-Mental State Examination orientation subtest to 177 alert patients 7–10 days and 3 months after stroke and 240 stroke-free nondemented subjects. Disorientation was defined as a score 8/10. Seventy-two (40.7%) of the patients were disoriented 7–10 days after stroke and 39 patients (22.0% of the sample) remained disoriented 3 months later. A logistic regression analysis determined that persistent disorientation was significantly related to stroke status [odds ratio (OR)=5.8], after adjusting for memory and attentional deficits and demographic variables. Among stroke patients, disorientation was associated with severe hemispheral stroke syndromes (OR=7.7), but not infarct location or vascular risk factor history, after adjusting for memory and attentional deficits and demographic variables. Sensitivity and specificity analyses determined that disorientation was an inaccurate marker for dementia or deficits in memory or attention, while intact orientation was associated with a low probability of dementia or memory dysfunction in most patients but not preserved attention. We conclude that disorientation is common and persistent following stroke and associated with severe hemispheral stroke syndromes but not infarct location. While disorientation is a poor marker for dementia or deficits in memory or attention, intact orientation should suggest that cognitive functions are likely to be preserved.Presented in part at the 118th Annual Meeting of the American Neurological Association, Boston, Massachusetts, October 1993  相似文献   
96.
97.
98.
99.
Advance directives, such as the durable power of attorney for health care (DPAHC), help patients and physicians make end-of-life health care decisions. Medical education should prepare student physicians to be knowledgeable about and comfortable with discussing advance directives. The authors developed an educational module for the third-year medical school curriculum and conducted a randomized trial to evaluate in students its effect on various outcome measures regarding the DPAHC. Over a six-week period, students who received written material about the DPAHC and a two-hour seminar significantly increased knowledge about and reported increased skill, comfort, and experience with the DPAHC.  相似文献   
100.
The 14q+ chromosome in pre-B-ALL   总被引:2,自引:0,他引:2  
Kaneko  Y; Rowley  JD; Check  I; Variakojis  D; Moohr  JW 《Blood》1980,56(5):782-785
A child who had acute lymphoblastic leukemia (ALL) associated with an 8;14 chromosome translocation and with a pre-B phenotype is described. The leukemic cells were determined to be pre-B-cells on the basis of intracytoplasmic mu-chain immunoglobulin (cIgM+) and the common-ALL antigen, lack of receptors for sheep erythrocytes, and lack of surface immunoglobulin. The 8;14 translocation is frequently found in patients with Burkitt's lymphoma and in most patients with B-cell ALL and is known to carry a poor prognosis. Thus far, no karyotypes have been reported for patients with pre-B-ALL. The present case indicates that a 14q+ chromosome may provide a proliferative advantage not only to cells with a B-cell phenotype, but also to pre-B-cells. The short survival of our patient also suggests that the 14q+ abnormality and the pre-B phenotype may signal a poor prognosis.  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