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   34871篇
  免费   7701篇
  国内免费   105篇
耳鼻咽喉   493篇
儿科学   822篇
妇产科学   843篇
基础医学   2457篇
口腔科学   1858篇
临床医学   9435篇
内科学   7292篇
皮肤病学   813篇
神经病学   3839篇
特种医学   1244篇
外科学   4750篇
综合类   384篇
现状与发展   2篇
一般理论   14篇
预防医学   3900篇
眼科学   716篇
药学   1293篇
中国医学   11篇
肿瘤学   2511篇
  2024年   144篇
  2023年   1362篇
  2022年   386篇
  2021年   922篇
  2020年   1272篇
  2019年   675篇
  2018年   1827篇
  2017年   1882篇
  2016年   1856篇
  2015年   1932篇
  2014年   2324篇
  2013年   2685篇
  2012年   1594篇
  2011年   1751篇
  2010年   1659篇
  2009年   1960篇
  2008年   1485篇
  2007年   1388篇
  2006年   1514篇
  2005年   1304篇
  2004年   1119篇
  2003年   1106篇
  2002年   1040篇
  2001年   593篇
  2000年   411篇
  1999年   557篇
  1998年   611篇
  1997年   597篇
  1996年   633篇
  1995年   554篇
  1994年   439篇
  1993年   372篇
  1992年   410篇
  1991年   360篇
  1990年   285篇
  1989年   319篇
  1988年   288篇
  1987年   254篇
  1986年   237篇
  1985年   266篇
  1984年   260篇
  1983年   211篇
  1982年   189篇
  1981年   159篇
  1980年   167篇
  1979年   125篇
  1978年   116篇
  1977年   102篇
  1976年   121篇
  1974年   96篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
3.
Despite orientation and mobility (O&M) being a significant factor determining quality of life of people with low vision or blindness, there are no gold standard measures or agreement on how to measure O&M performance. In the first part of this systematic review, an inventory of O&M outcome measures used by recent studies to assess the performance of orientation and/or mobility of adults with vision impairment (low vision and blindness) is presented. A wide variety of O&M outcome measures have been implemented in different fields of study, such as epidemiologic research and interventional studies evaluating training, assistive technology, vision rehabilitation and vision restoration. The most frequent aspect of outcome measures is efficiency such as time, distance, speed and percentage of preferred walking speed, followed by obstacle contacts and avoidance, and dis/orientation and veering. Other less commonly used aspects are target identification, safety and social interaction and self-reported outcome measures. Some studies employ sophisticated equipment to capture and analyse O&M performance in a laboratory setting, while others carry out their assessment in real-world indoor or outdoor environments. In the second part of this review, the appropriateness of implementing the identified outcome measures to assess O&M performance in clinical and functional O&M practice is evaluated. Nearly a half of these outcome measures meet all four criteria of face validity (either clinical or functional), responsiveness, reliability and feasibility and have the potential to be implemented in clinical or functional O&M practice. The findings of this review confirm the complicated and dynamic nature of O&M. Multiple measures are required in any evaluation of O&M performance to facilitate holistic assessment of O&M abilities and limitations of each individual.  相似文献   
4.
Although depression is associated to physical discomfort, meanings of the body in depression are rarely addressed in clinical research. Drawing on the concept of the lived body, this study explores depression as an embodied phenomenon. Using a hermeneutic phenomenological approach, the analysis of narrative‐based interviews with 11 depressed adults discloses a thematic structure of an embodied process of an ambiguous striving against fading. Five subthemes elicit different dimensions of this process, interpreted as disabling or enabling: feeling estranged, feeling confined, feeling burdensome, sensing life and seeking belongingness. In relation to clinical practice, we suggest that the interdisciplinary team can focus on enhancing the enabling dimensions, for example through guided physical activities to support the patient to feel more alive, capable and connected. Moreover, we suggest that the treatment process benefits from an increased awareness of the ambiguity in the patient's struggle, acknowledging both destructive and recharging elements of the withdrawing, and the perceived conflict in‐between.  相似文献   
5.
6.
7.
8.
9.
10.
Iron deficiency anemia is often listed among potential adverse effects of gastric acid-suppressive medications, given that gastric acidity promotes intestinal absorption of nonheme iron. Additionally, the antacid calcium carbonate can inhibit iron absorption. However, there is little direct clinical evidence that proton-pump inhibitors, histamine-2 receptor antagonists, or calcium carbonate cause iron deficiency anemia. Most case reports have had substantial limitations (e.g., minimal follow-up and presence of other causes of iron deficiency), and retrospective cohort studies have lacked sufficient patient-specific detail to make strong causal inferences. We present 2 cases—both with detailed, prospective 10-year follow-up—in which combinations of proton-pump inhibitors, histamine-2 receptor antagonists and calcium carbonate were clearly associated with development of iron deficiency anemia. Overt iron-deficiency anemia is probably uncommon in patients who use acid-modifying medications and who have no other conditions that predispose to iron deficiency. Nevertheless, clinicians should be aware of this potential complication, given widespread use of these agents.  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