全文获取类型
收费全文 | 231968篇 |
免费 | 17060篇 |
国内免费 | 798篇 |
专业分类
耳鼻咽喉 | 2615篇 |
儿科学 | 6167篇 |
妇产科学 | 4700篇 |
基础医学 | 30225篇 |
口腔科学 | 4847篇 |
临床医学 | 22079篇 |
内科学 | 49231篇 |
皮肤病学 | 3640篇 |
神经病学 | 22554篇 |
特种医学 | 7935篇 |
外国民族医学 | 15篇 |
外科学 | 36241篇 |
综合类 | 3609篇 |
现状与发展 | 2篇 |
一般理论 | 296篇 |
预防医学 | 20576篇 |
眼科学 | 4746篇 |
药学 | 15803篇 |
1篇 | |
中国医学 | 409篇 |
肿瘤学 | 14135篇 |
出版年
2023年 | 953篇 |
2022年 | 1508篇 |
2021年 | 3747篇 |
2020年 | 2310篇 |
2019年 | 3639篇 |
2018年 | 4552篇 |
2017年 | 3621篇 |
2016年 | 3929篇 |
2015年 | 4615篇 |
2014年 | 6646篇 |
2013年 | 9697篇 |
2012年 | 14600篇 |
2011年 | 15829篇 |
2010年 | 8811篇 |
2009年 | 7902篇 |
2008年 | 14767篇 |
2007年 | 15688篇 |
2006年 | 15139篇 |
2005年 | 15534篇 |
2004年 | 14893篇 |
2003年 | 13897篇 |
2002年 | 13388篇 |
2001年 | 2439篇 |
2000年 | 1989篇 |
1999年 | 2580篇 |
1998年 | 2998篇 |
1997年 | 2589篇 |
1996年 | 2330篇 |
1995年 | 2079篇 |
1994年 | 1888篇 |
1993年 | 1762篇 |
1992年 | 1450篇 |
1991年 | 1437篇 |
1990年 | 1280篇 |
1989年 | 1192篇 |
1988年 | 1215篇 |
1987年 | 1228篇 |
1986年 | 1191篇 |
1985年 | 1289篇 |
1984年 | 1607篇 |
1983年 | 1600篇 |
1982年 | 1903篇 |
1981年 | 1739篇 |
1980年 | 1625篇 |
1979年 | 937篇 |
1978年 | 1050篇 |
1977年 | 1022篇 |
1976年 | 911篇 |
1975年 | 795篇 |
1974年 | 780篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
John Bickle 《Topics in Cognitive Science》2015,7(2):299-311
David Marr's three-level method for completely understanding a cognitive system and the importance he attaches to the computational level are so familiar as to scarcely need repeating. Fewer seem to recognize that Marr defends his famous method by criticizing the “reductionistic approach.” This sets up a more interesting relationship between Marr and reductionism than is usually acknowledged. I argue that Marr was correct in his criticism of the reductionists of his time—they were only describing (cellular activity), not explaining (cognitive functions). But a careful metascientific account of reductionistic neuroscience over the past two decades reveals that Marr's criticisms no longer have force. Contemporary neuroscience now explains cognition directly, although in a fashion—causal-mechanistically—quite different than Marr recommended. So while Marr was correct to reject the reductionism of his day and offer an alternative method for genuinely explaining cognition, contemporary cognitive scientists now owe us a new defense of Marr's famous method and the advantages of its explanations over the type now pursued successfully in current reductionist neuroscience. There are familiar reasons for thinking that this debt will not be paid easily. 相似文献
12.
13.
14.
Xin Yi Wong Andrew Qi Jun Lim Qianyu Shen John Whay Kuang Chia Min Hoe Chew Wah Siew Tan 《Current medical research and opinion》2020,36(10):1677-1686
Abstract
Objective
Ras wild-type metastatic colorectal cancers (mCRC) may be treated with anti-vascular endothelial growth factor (VEGF) or anti-epidermal growth factor receptor (EGFR) agents. We aim to estimate patients’ preferences for mCRC treatment and relative importance of cost, efficacy improvement, avoidance of side effects and therapy convenience, and relative uptake between profiles that resemble Bevacizumab (anti-VEGF) and Cetuximab (anti-EGFR), two commonly prescribed mCRC targeted therapies. 相似文献15.
16.
Katja T. Turunen Vasiliki Pletsa Panagiotis Georgiadis John K. Triantafillidis Dimitrios Karamanolis 《Nutrition and cancer》2016,68(4):560-567
The aim of the study was to determine the effect of β-glucan on the cytotoxicity and genotoxicity of polypectomized patient's fecal water (FW). Polypectomized volunteers (n = 69) were randomly assigned to consume bread with or without β-glucan, for 3 months. FW was collected at the beginning (t = 0), the 30th and 90th day and 2 wk after the intervention. Cytotoxicity and genotoxicity were estimated on Caco-2 cells, using trypan blue exclusion test and comet assay, respectively. Gastrointestinal symptoms were recorded and subjects kept a 3-day food diary at baseline and after completion. Trypan blue exclusion test revealed cell survival of approximately 87% after incubation with FW. The FW samples showed 49% genotoxicity at the baseline. Genotoxicity in the intervention group decreased during the trial reaching statistical significance on the 90th day compared to control. An increase was noticed 2 wk after the trial, but it still remained significantly lower compared to control. Group-specific analysis for β-glucan also revealed significant decrease in the genotoxicity on the 90th day compared to baseline. β-glucan ingestion in polypectomized patients significantly decreased the genotoxicity of their FW. Our findings suggest that β-glucan consumption could possibly provide protection against colon cancer development. 相似文献
17.
Rebecca L. King Albert C. Yan Debora R. Sekiguchi John K. Choi 《Journal of cutaneous pathology》2015,42(12):1012-1017
Reactive lymphoid infiltrates of the skin composed predominantly of gamma‐delta (γδ) T cells are not well described in the literature. Herein we report a case of an otherwise healthy 4‐year‐old male who presented with a waxing and waning papular rash characterized by small, discrete crusted papules spread across his trunk, face and extremities. Clinical evaluation revealed no evidence of systemic disease. Microscopic examination revealed a dermal, perivascular infiltrate of highly atypical lymphocytes with a γδ T cell phenotype, worrisome for primary cutaneous γδ T cell lymphoma. The clinical course, however, was that of a reactive condition and prompted consideration of a diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP). In many ways, this case defies current classification schemes and seems to expand the spectrum of reactive γδ T cell infiltrates of the skin. 相似文献
18.
19.
Marta Rozanski Valentin Neuhaus Emily Thornton Stéphanie J. E. Becker James P. Rathmell David Ring 《Journal of hand and microsurgery》2015,7(1):30-35
This study used the National Survey of Ambulatory Surgery (NSAS) database to measure the incidence of and risk factors for symptoms in the ambulatory surgery center and problems within 24 h after isolated carpal tunnel release (CTR). The NSAS contained records on 400,000 adult patients with carpal tunnel syndrome who were treated with CTR in 2006, based on ICD-9 codes. The type of anesthesia used and factors associated with symptoms and problems were sought in bivariate and multivariable statistical analyses. The mean duration of the procedure was 16 ± 8.8 min. Only 5 % were performed under local anesthesia without sedation, 45 % with IV sedation, 28 % regional anesthesia, and 19 % general anesthesia. Symptoms in the ambulatory surgery center or a problem within 24 h after discharge were recorded in 10 % of patients, all of them minor and transient, including difficulties with pain and its treatment. The strongest risk factors were male sex, age of 45 years and older, and participation of an anesthesiologist. Local anesthesia and regional anesthesia were associated with more perioperative symptoms and postoperative problems. Most CTR are performed with some sedation in the United States. CTR is a safe procedure: one in 10 patients will experience a minor issue in the perioperative or immediate postoperative period. 相似文献