全文获取类型
收费全文 | 2341篇 |
免费 | 143篇 |
国内免费 | 76篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 177篇 |
妇产科学 | 29篇 |
基础医学 | 278篇 |
口腔科学 | 68篇 |
临床医学 | 270篇 |
内科学 | 649篇 |
皮肤病学 | 80篇 |
神经病学 | 104篇 |
特种医学 | 394篇 |
外科学 | 120篇 |
综合类 | 44篇 |
预防医学 | 113篇 |
眼科学 | 23篇 |
药学 | 95篇 |
2篇 | |
肿瘤学 | 113篇 |
出版年
2023年 | 6篇 |
2022年 | 6篇 |
2021年 | 15篇 |
2020年 | 20篇 |
2019年 | 21篇 |
2018年 | 43篇 |
2017年 | 30篇 |
2016年 | 30篇 |
2015年 | 45篇 |
2014年 | 57篇 |
2013年 | 68篇 |
2012年 | 51篇 |
2011年 | 68篇 |
2010年 | 94篇 |
2009年 | 93篇 |
2008年 | 68篇 |
2007年 | 106篇 |
2006年 | 71篇 |
2005年 | 67篇 |
2004年 | 45篇 |
2003年 | 35篇 |
2002年 | 41篇 |
2001年 | 48篇 |
2000年 | 49篇 |
1999年 | 41篇 |
1998年 | 131篇 |
1997年 | 155篇 |
1996年 | 132篇 |
1995年 | 111篇 |
1994年 | 115篇 |
1993年 | 97篇 |
1992年 | 37篇 |
1991年 | 43篇 |
1990年 | 42篇 |
1989年 | 62篇 |
1988年 | 51篇 |
1987年 | 44篇 |
1986年 | 49篇 |
1985年 | 46篇 |
1984年 | 30篇 |
1983年 | 16篇 |
1982年 | 26篇 |
1981年 | 29篇 |
1980年 | 26篇 |
1979年 | 8篇 |
1978年 | 10篇 |
1977年 | 21篇 |
1976年 | 26篇 |
1975年 | 20篇 |
1972年 | 4篇 |
排序方式: 共有2560条查询结果,搜索用时 15 毫秒
1.
JM Martín† L Calduch† C Monteagudo‡ I Molina† D Ramón† V Alonso† E Jordᆠ《Journal of the European Academy of Dermatology and Venereology》2006,20(4):428-431
Cutaneous plasmacytosis is a rare disorder characterized by a benign proliferation of mature plasma cells that appears as multiple dark-brown to purplish skin lesions, often associated with polyclonal hypergammaglobulinaemia. We present the case of a 55-year-old Caucasian man who suffered from a cutaneous plasmacytosis associated with two different carcinomas. Cutaneous plasmacytosis seems to be a reactive process because most cases reported are not associated with any apparent underlying disease. Nevertheless, because few reported cases were associated with malignancies, screening of additional neoplasms would be justified. 相似文献
2.
3.
Chu‐Lin Tsai MD MPH Justin A. Sobrino BS Carlos A. Camargo Jr MD DrPH 《Academic emergency medicine》2008,15(12):1275-1283
Objectives: Little is known about recent trends in U.S. emergency department (ED) visits for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) or about ED management of AECOPD. This study aimed to describe the epidemiology of ED visits for AECOPD and to evaluate concordance with guideline‐recommended care. Methods: Data were obtained from National Hospital Ambulatory Medical Care Survey (NHAMCS). ED visits for AECOPD, during 1993 to 2005, were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) codes. Concordance with guideline recommendations was evaluated using process measures. Results: Over the 13‐year study period, there was an average annual 0.6 million ED visits for AECOPD, and the visit rates for AECOPD were consistently high (3.2 per 1,000 U.S. population; Ptrend = 0.13). The trends in the use of chest radiograph, pulse oximetry, or bronchodilator remained stable (all Ptrend > 0.5). By contrast, the use of systemic corticosteroids increased from 29% in 1993–1994 to 60% in 2005, antibiotics increased from 14% to 42%, and methylxanthines decreased from 15% to <1% (all Ptrend < 0.001). Multivariable analysis showed patients in the South (vs. the Northeast) were less likely to receive systemic corticosteroids (odds ratio [OR] = 0.6; 95% confidence interval [CI] = 0.4 to 0.9). Conclusions: The high burden of ED visits for AECOPD persisted. Overall concordance with guideline‐recommended care for AECOPD was moderate, and some emergency treatments had improved over time. 相似文献
4.
JM Vilanova J Figueras-Aloy J Roselló G Gómez E Gelpí R Jiménez 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(5):588-592
The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF 1-α, TXB2 , PGE2 and PGF2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB2 (thromboxane A2 metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF 1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB2 was higher than the rise in 6-keto-PGF 1-α . 相似文献
5.
6.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
7.
8.
9.
10.