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   43125篇
  免费   3278篇
  国内免费   167篇
耳鼻咽喉   325篇
儿科学   1249篇
妇产科学   852篇
基础医学   5321篇
口腔科学   854篇
临床医学   4369篇
内科学   9681篇
皮肤病学   623篇
神经病学   4394篇
特种医学   1323篇
外国民族医学   1篇
外科学   6019篇
综合类   634篇
一般理论   46篇
预防医学   3805篇
眼科学   788篇
药学   3046篇
  1篇
中国医学   56篇
肿瘤学   3183篇
  2023年   230篇
  2022年   319篇
  2021年   820篇
  2020年   544篇
  2019年   811篇
  2018年   931篇
  2017年   700篇
  2016年   759篇
  2015年   909篇
  2014年   1311篇
  2013年   1850篇
  2012年   2682篇
  2011年   3010篇
  2010年   1671篇
  2009年   1531篇
  2008年   2567篇
  2007年   2856篇
  2006年   2654篇
  2005年   2812篇
  2004年   2560篇
  2003年   2422篇
  2002年   2255篇
  2001年   571篇
  2000年   474篇
  1999年   594篇
  1998年   529篇
  1997年   411篇
  1996年   405篇
  1995年   341篇
  1994年   305篇
  1993年   316篇
  1992年   411篇
  1991年   404篇
  1990年   354篇
  1989年   321篇
  1988年   324篇
  1987年   300篇
  1986年   241篇
  1985年   302篇
  1984年   337篇
  1983年   294篇
  1982年   302篇
  1981年   309篇
  1980年   293篇
  1979年   186篇
  1978年   201篇
  1977年   166篇
  1976年   132篇
  1974年   120篇
  1972年   108篇
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
1.
Cancer Causes & Control - Congenital malformations are strong risk factors for childhood cancer. Our objective was to determine whether cancer survival differs by birth defect status among...  相似文献   
2.
3.
4.
Coronary embolism (CE) is an uncommon and unique cause of acute myocardial infarction. In this report, we review 216 cases of CE including 2 new cases from our institution. The mean patient age was 52.5 years and 62% of the patients were males. Chest pain was the most common presenting symptom followed by dyspnea, and the most commonly affected vessel was the left anterior descending artery. Leading etiologies of the embolus were atrial fibrillation, septic emboli, and iatrogenic causes. Treatment approaches varied with thrombus aspiration being used in 30% of cases. In-hospital mortality rate was 36% and 13% of the cases were complicated by cerebrovascular accident. CE is a unique pathology that leads to acute myocardial infarction. It portends a high mortality rate and requires a high level of suspicion as symptoms may be misleading. Further research is needed in order to improve recognition and management and to lower associated mortality.  相似文献   
5.
6.
7.
Background A high Mandard score implies a non-response to chemotherapy in oesophageal adenocarcinoma. However, some patients exhibit tumour volume reduction and a nodal response despite a high score. This study examines survival and recurrence patterns in these patients.Methods Clinicopathological factors were analysed using multivariable Cox regression assessing time to death and recurrence. Computed tomography-estimated tumour volume change was examined in a subgroup of consecutive patients.Results Five hundred and fifty-five patients were included. Median survival was 55 months (Mandard 1–3) and 21 months (Mandard 4 and 5). In the Mandard 4 and 5 group (332 patients), comparison between complete nodal responders and persistent nodal disease showed improved survival (90 vs 18 months), recurrence rates (locoregional 14.75 vs 28.74%, systemic 24.59 vs 48.42%) and circumferential resection margin positivity (22.95 vs 68.11%). Complete nodal response independently predicted improved survival (hazard ratio 0.34 (0.16–0.74). Post-chemotherapy tumour volume reduction was greater in patients with a complete nodal response (−16.3 vs −7.7 cm3, p = 0.033) with no significant difference between Mandard groups.Conclusion Patients with a complete nodal response to chemotherapy have significantly improved outcomes despite a poor Mandard score. High Mandard score does not correspond with a non-response to chemotherapy in all cases and patients with nodal downstaging may still benefit from adjuvant chemotherapy.Subject terms: Oesophageal cancer, Surgical oncology  相似文献   
8.
There are an estimated 56 million orphans and vulnerable children across sub-Saharan Africa. Communities typically care for orphan children through informal caring arrangements – either within or outside of kinship networks. Within Kenya, an estimated 250,000 children live on the streets. There is less research related to fostering attitudes of this special population than orphans and vulnerable children generally. Important research over the past decade has illuminated multiple ways in which children are made more vulnerable because of HIV, including parental death and street-migration from HIV-affected households. As HIV transitions from a terminal illness to a chronic, manageable one, research is also required to establish how parents living with HIV can be an asset to children. In this study, we assess whether mothers living with HIV were very willing to foster biologically-related children, and street-involved children, how these fostering attitudes differed from mothers not living with HIV, and whether differences in fostering attitudes by reported HIV status were mediated by social support, family functioning and general self-rated health. Approximately 40% of mothers living with HIV were very willing to provide long-term foster care to biologically-related or street-involved children. This was less than the percentage of mothers not living with HIV, who were very willing to foster biologically-related children (61%) or street-involved children (58%). Significant portions of these differences were explained by social support, family functioning and general self-rated health. Multi-sectoral approaches are suggested by these findings in order to improve the child-fostering capacity of mothers living with HIV. Improving social support, family functioning and general self-rated health among HIV-infected mothers may not only provide protective benefits for the mothers and their children, but also expand the community’s capacity to care for orphan and vulnerable children.  相似文献   
9.
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