全文获取类型
收费全文 | 53903篇 |
免费 | 3952篇 |
国内免费 | 122篇 |
专业分类
耳鼻咽喉 | 587篇 |
儿科学 | 1927篇 |
妇产科学 | 1338篇 |
基础医学 | 6755篇 |
口腔科学 | 835篇 |
临床医学 | 8096篇 |
内科学 | 9445篇 |
皮肤病学 | 678篇 |
神经病学 | 5087篇 |
特种医学 | 1327篇 |
外国民族医学 | 1篇 |
外科学 | 6102篇 |
综合类 | 658篇 |
一般理论 | 67篇 |
预防医学 | 6828篇 |
眼科学 | 788篇 |
药学 | 3587篇 |
2篇 | |
中国医学 | 52篇 |
肿瘤学 | 3817篇 |
出版年
2023年 | 338篇 |
2022年 | 463篇 |
2021年 | 1063篇 |
2020年 | 736篇 |
2019年 | 1162篇 |
2018年 | 1341篇 |
2017年 | 991篇 |
2016年 | 1067篇 |
2015年 | 1202篇 |
2014年 | 1678篇 |
2013年 | 2598篇 |
2012年 | 3774篇 |
2011年 | 4027篇 |
2010年 | 2111篇 |
2009年 | 1927篇 |
2008年 | 3431篇 |
2007年 | 3447篇 |
2006年 | 3399篇 |
2005年 | 3262篇 |
2004年 | 3042篇 |
2003年 | 2761篇 |
2002年 | 2580篇 |
2001年 | 692篇 |
2000年 | 696篇 |
1999年 | 674篇 |
1998年 | 620篇 |
1997年 | 456篇 |
1996年 | 409篇 |
1995年 | 350篇 |
1994年 | 330篇 |
1993年 | 341篇 |
1992年 | 519篇 |
1991年 | 465篇 |
1990年 | 456篇 |
1989年 | 438篇 |
1988年 | 425篇 |
1987年 | 391篇 |
1986年 | 378篇 |
1985年 | 410篇 |
1984年 | 352篇 |
1983年 | 285篇 |
1982年 | 233篇 |
1981年 | 219篇 |
1980年 | 188篇 |
1979年 | 276篇 |
1978年 | 202篇 |
1977年 | 160篇 |
1976年 | 137篇 |
1974年 | 135篇 |
1973年 | 136篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Karl Johnson Katherine W. Saylor Isabella Guynn Karen Hicklin Jonathan S. Berg Kristen Hassmiller Lich 《Genetics in medicine》2022,24(2):262-288
PurposeUnderstanding the value of genetic screening and testing for monogenic disorders requires high-quality, methodologically robust economic evaluations. This systematic review sought to assess the methodological quality among such studies and examined opportunities for improvement.MethodsWe searched PubMed, Cochrane, Embase, and Web of Science for economic evaluations of genetic screening/testing (2013-2019). Methodological rigor and adherence to best practices were systematically assessed using the British Medical Journal checklist.ResultsAcross the 47 identified studies, there were substantial variations in modeling approaches, reporting detail, and sophistication. Models ranged from simple decision trees to individual-level microsimulations that compared between 2 and >20 alternative interventions. Many studies failed to report sufficient detail to enable replication or did not justify modeling assumptions, especially for costing methods and utility values. Meta-analyses, systematic reviews, or calibration were rarely used to derive parameter estimates. Nearly all studies conducted some sensitivity analysis, and more sophisticated studies implemented probabilistic sensitivity/uncertainty analysis, threshold analysis, and value of information analysis.ConclusionWe describe a heterogeneous body of work and present recommendations and exemplar studies across the methodological domains of (1) perspective, scope, and parameter selection; (2) use of uncertainty/sensitivity analyses; and (3) reporting transparency for improvement in the economic evaluation of genetic screening/testing. 相似文献
2.
Karen Kayser Ariel Washington Lesley M. Harris Barbara Head 《Journal of psychosocial oncology》2021,39(1):17-34
Abstract
Purpose
Financial hardship can be a major cause of distress among persons with cancer, resulting in chronic stress and impacting physical and emotional health. This paper provides an analysis of the lived experience of cancer patients’ financial hardship from diagnosis to post-treatment. 相似文献3.
4.
5.
6.
7.
Emma J. Kilford Iroise Dumontheil Nicholas W. Wood Sarah-Jayne Blakemore 《Social cognitive and affective neuroscience》2015,10(6):777-782
The catechol-O-methyltransferase (COMT) enzyme is a major determinant of prefrontal dopamine levels. The Val158Met polymorphism affects COMT enzymatic activity and has been associated with variation in executive function and affective processing. This study investigated the effect of COMT genotype on the flexible modulation of the balance between processing self-generated and processing stimulus-oriented information, in the presence or absence of affective distractors. Analyses included 124 healthy adult participants, who were also assessed on standard working memory (WM) tasks. Relative to Val carriers, Met homozygotes made fewer errors when selecting and manipulating self-generated thoughts. This effect was partly accounted for by an association between COMT genotype and visuospatial WM performance. We also observed a complex interaction between the influence of affective distractors, COMT genotype and sex on task accuracy: male, but not female, participants showed a sensitivity to the affective distractors that was dependent on COMT genotype. This was not accounted for by WM performance. This study provides novel evidence of the role of dopaminergic genetic variation on the ability to select and manipulate self-generated thoughts. The results also suggest sexually dimorphic effects of COMT genotype on the influence of affective distractors on executive function. 相似文献
8.
Can EGFR mutation status be reliably determined in pre‐operative needle biopsies from adenocarcinomas of the lung? 下载免费PDF全文
Kim Hein Lindahl Flemming Brandt Sørensen Søren Peter Jonstrup Karen Ege Olsen Siegfried Loeschke 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(4):289-297
The identification of EGFR mutations in non‐small‐cell lung cancer is important for selecting patients, who may benefit from treatment with EGFR tyrosine kinase inhibitors. The analysis is usually performed on cytological aspirates and/or histological needle biopsies, representing a small fraction of the tumour volume. The aim of the present investigation was to evaluate the diagnostic performance of this molecular test. We retrospectively included 201 patients with primary adenocarcinoma of the lung. EGFR mutation status (exon 19 deletions and exon 21 L858R point mutation) was evaluated on both pre‐operative biopsies (131 histological and 70 cytological) and on the surgical specimens, using PCR. Samples with low tumour cell fraction were assigned to laser micro‐dissection (LMD). We found nine (4.5%) patients with EGFR mutation in the lung tumour resections, but failed to identify mutation in one of the corresponding pre‐operative, cytological specimens. Several (18.4%) analyses of the pre‐operative biopsies were inconclusive, especially in case of biopsies undergoing LMD and regarding exon 21 analysis. Discrepancy of mutation status in one patient may reflect intra‐tumoural heterogeneity or technical issues. Moreover, several inconclusive results in the diagnostic biopsies reveal that attention must be paid on the suitability of pre‐operative biopsies for EGFR mutation analysis. 相似文献
9.
10.