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   7431篇
  免费   454篇
  国内免费   52篇
耳鼻咽喉   59篇
儿科学   94篇
妇产科学   63篇
基础医学   1066篇
口腔科学   121篇
临床医学   785篇
内科学   1694篇
皮肤病学   157篇
神经病学   833篇
特种医学   358篇
外科学   975篇
综合类   30篇
一般理论   14篇
预防医学   511篇
眼科学   91篇
药学   605篇
中国医学   33篇
肿瘤学   448篇
  2023年   41篇
  2022年   34篇
  2021年   126篇
  2020年   122篇
  2019年   170篇
  2018年   198篇
  2017年   142篇
  2016年   176篇
  2015年   219篇
  2014年   297篇
  2013年   389篇
  2012年   599篇
  2011年   614篇
  2010年   362篇
  2009年   342篇
  2008年   566篇
  2007年   584篇
  2006年   513篇
  2005年   480篇
  2004年   423篇
  2003年   362篇
  2002年   347篇
  2001年   45篇
  2000年   42篇
  1999年   51篇
  1998年   59篇
  1997年   51篇
  1996年   32篇
  1995年   47篇
  1994年   24篇
  1993年   36篇
  1992年   25篇
  1991年   17篇
  1990年   23篇
  1989年   19篇
  1988年   15篇
  1987年   26篇
  1986年   27篇
  1985年   16篇
  1984年   12篇
  1983年   9篇
  1982年   22篇
  1981年   20篇
  1980年   18篇
  1978年   15篇
  1977年   9篇
  1976年   13篇
  1973年   13篇
  1971年   10篇
  1963年   8篇
排序方式: 共有7937条查询结果,搜索用时 15 毫秒
1.
The prospective, multicenter, noninterventional TACTIC study assessed effectiveness and safety of trifluridine/tipiracil (FTD/TPI) in patients with metastatic colorectal cancer (mCRC) in a real-world setting in Germany, thus evaluating the external validity of the findings from the pivotal RECOURSE trial. Primary endpoint was overall survival (OS). Secondary objectives included progression-free survival (PFS), safety, and quality of life (QoL). Subgroups comprised patients with good (<3 metastatic sites at inclusion, ≥18 months from diagnosis of first metastasis to inclusion) or poor (remaining patients) prognostic characteristics (GPC/PPC). GPC without liver metastases was considered best prognostic characteristics (BPC). In total, 307 eligible patients (pretreated or not suitable for other available therapies) were treated with FTD/TPI. Overall, median [95%-CI] OS was 7.4 months [6.4-8.6], median PFS was 2.9 months [2.8-3.3]. In BPC (n = 65) and GPC (n = 176) compared to PPC (n = 124) subgroup, median OS (13.3 [9.1-17.6] vs 8.9 [7.6-9.8] vs 5.1 [4.4-7.0] months) and median PFS (4.0 [3.3-5.3] vs 3.4 [3.0-3.7] vs 2.6 [2.4-2.8] months) were longer. Patient-reported QoL, assessed by validated questionnaires (EQ-5D-5L, PRO-CTCAE), was stable throughout FTD/TPI treatment. Predominant FTD/TPI-related adverse events of grades 3 or 4 were neutropenia (13.0%), leukopenia (7.5%), and anemia (5.2%). Altogether, palliative FTD/TPI therapy in patients with pretreated mCRC was associated with prolonged survival, delayed progression, maintained health-related QoL, and manageable toxicity. Low metastatic burden and indolent disease were favorable prognostic factors for survival. TACTIC confirms the effectiveness and safety of FTD/TPI, highlighting its value in routine clinical practice.  相似文献   
2.
3.

Objectives

The predictive value of frailty and comorbidity, in addition to more readily available information, is not widely studied. We determined the incremental predictive value of frailty and comorbidity for mortality and institutionalization across both short and long prediction periods in persons with dementia.

Design

Longitudinal clinical cohort study with a follow-up of institutionalization and mortality occurrence across 7 years after baseline.

Setting and Participants

331 newly diagnosed dementia patients, originating from 3 Alzheimer centers (Amsterdam, Maastricht, and Nijmegen) in the Netherlands, contributed to the Clinical Course of Cognition and Comorbidity (4C) Study.

Measures

We measured comorbidity burden using the Cumulative Illness Rating Scale for Geriatrics (CIRS-G) and constructed a Frailty Index (FI) based on 35 items. Time-to-death and time-to-institutionalization from dementia diagnosis onward were verified through linkage to the Dutch population registry.

Results

After 7 years, 131 patients were institutionalized and 160 patients had died. Compared with a previously developed prediction model for survival in dementia, our Cox regression model showed a significant improvement in model concordance (U) after the addition of baseline CIRS-G or FI when examining mortality across 3 years (FI: U = 0.178, P = .005, CIRS-G: U = 0.180, P = .012), but not for mortality across 6 years (FI: U = 0.068, P = .176, CIRS-G: U = 0.084, P = .119). In a competing risk regression model for time-to-institutionalization, baseline CIRS-G and FI did not improve the prediction across any of the periods.

Conclusions

Characteristics such as frailty and comorbidity change over time and therefore their predictive value is likely maximized in the short term. These results call for a shift in our approach to prognostic modeling for chronic diseases, focusing on yearly predictions rather than a single prediction across multiple years. Our findings underline the importance of considering possible fluctuations in predictors over time by performing regular longitudinal assessments in future studies as well as in clinical practice.  相似文献   
4.
Journal of Neuro-Oncology - Gliomatosis cerebri (GC) is a rare growth pattern of glioblastoma whose diffuse nature is reflected by unspecific, relatively uniform findings on conventional MRI. In...  相似文献   
5.
6.
7.
Most rehabilitation treatments are volitional in nature, meaning that they require the patient’s active engagement and effort. Volitional treatments are particularly challenging to define in a standardized fashion, because the clinician is not in complete control of the patient’s role in enacting these treatments. Current recommendations for describing treatments in research reports fail to distinguish between 2 fundamentally different aspects of treatment design: the selection of treatment ingredients to produce the desired functional change and the selection of ingredients that will ensure the patient’s volitional performance. The Rehabilitation Treatment Specification System (RTSS) is a conceptual scheme for standardizing the way that rehabilitation treatments are defined by all disciplines across all areas of rehabilitation. The RTSS highlights the importance of volitional behavior in many treatment areas and provides specific guidance for how volitional treatments should be specified. In doing so, it suggests important crosscutting research questions about the nature of volitional behavior, factors that make it more or less likely to occur, and ingredients that are most effective in ensuring that patients perform desired treatment activities.  相似文献   
8.
9.
Odontology - The aim of this study was to evaluate the biocompatibility of two comparatively new calcium silicate containing sealers (MTA-Fillapex and BioRoot-RCS) with that of two established...  相似文献   
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