全文获取类型
收费全文 | 4018篇 |
免费 | 315篇 |
国内免费 | 77篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 194篇 |
妇产科学 | 74篇 |
基础医学 | 452篇 |
口腔科学 | 75篇 |
临床医学 | 552篇 |
内科学 | 843篇 |
皮肤病学 | 155篇 |
神经病学 | 158篇 |
特种医学 | 459篇 |
外科学 | 380篇 |
综合类 | 105篇 |
预防医学 | 447篇 |
眼科学 | 40篇 |
药学 | 232篇 |
2篇 | |
肿瘤学 | 233篇 |
出版年
2023年 | 18篇 |
2022年 | 18篇 |
2021年 | 40篇 |
2020年 | 51篇 |
2019年 | 46篇 |
2018年 | 87篇 |
2017年 | 48篇 |
2016年 | 66篇 |
2015年 | 62篇 |
2014年 | 97篇 |
2013年 | 127篇 |
2012年 | 138篇 |
2011年 | 141篇 |
2010年 | 139篇 |
2009年 | 127篇 |
2008年 | 142篇 |
2007年 | 174篇 |
2006年 | 144篇 |
2005年 | 139篇 |
2004年 | 105篇 |
2003年 | 93篇 |
2002年 | 99篇 |
2001年 | 99篇 |
2000年 | 81篇 |
1999年 | 73篇 |
1998年 | 173篇 |
1997年 | 195篇 |
1996年 | 161篇 |
1995年 | 146篇 |
1994年 | 136篇 |
1993年 | 121篇 |
1992年 | 71篇 |
1991年 | 77篇 |
1990年 | 81篇 |
1989年 | 87篇 |
1988年 | 83篇 |
1987年 | 78篇 |
1986年 | 70篇 |
1985年 | 76篇 |
1984年 | 42篇 |
1983年 | 36篇 |
1982年 | 39篇 |
1981年 | 44篇 |
1980年 | 41篇 |
1979年 | 29篇 |
1978年 | 31篇 |
1977年 | 36篇 |
1976年 | 40篇 |
1975年 | 26篇 |
1974年 | 20篇 |
排序方式: 共有4410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.
4.
5.
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
6.
7.
Martin F. Ward Angie Titchen Clare Morrell Brendan McCormack Alison Kitson 《Journal of clinical nursing》1998,7(1):29-36
? The paper describes a multiproject practice development programme undertaken over a period of 1 year. ? The background and development of the programme are outlined, whilst attention is paid to the innovatory nature of the work, particularly the use of inductive, deductive and integrated approaches to both change implementation and project supervision. ? The programme was monitored throughout using different data sources and the paper uses evaluative material retrospectively to provide answers to organizational and professional difficulties which arose during the course of the programme. ? The authors conclude that the use of combinations of different models for practice development has potential, but requires careful supervision. ? They also recommend that those involved in practice development are made fully aware of its local or micropolitics, and develop strategies to deal with change before it occurs, not after it has taken place. 相似文献
8.
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
9.
10.
A E Koch J Kampen K Tetzlaff M Reuter P McCormack P W Schnoor N Struck L Heine I Prytulla H Rieckert 《Undersea & hyperbaric medicine》2004,31(2):261-268
BACKGROUND: To investigate incidence and number of abnormal cerebral hyperintensities (ACFs) in Magnet Resonance Imaging (MRI) and its relation to a patent foramen ovale (PFO) in divers with no history of decompression illness. METHODS: Cohort study on 50 divers (21-5500 dives). MAIN OUTCOME MEASURES: Incidence and number of ACFs visualized by cranial MRI and presence and size of a PFO as documented by echocardiography and transcranial Doppler ultrasound (TCD) with echocontrast. RESULTS: A total of 137 ACFs was found in the 50 subjects, with a significant correlation between the number of dives and number of ACFs (r = 0.28; p < 0.05); but after correction for age, the remaining correlation (r = 0.15) did not reach significance. In 18 divers, a PFO was present by either the application of echocardiography or TCD; in 12 divers, the PFO was of high hemodynamic relevance. Ten of 18 divers with a PFO had at least one ACF, while in the remaining 32 divers, only 14 had at least one ACF (56% versus 44%, p = NS). Seven of 14 divers (50%) with 4 ACFs had a PFO, compared to 11 of 36 (31%) with less than 4 ACFs (p = NS). CONCLUSION: In this cohort of healthy divers, in contrast to an earlier report, no significant association was found between PFO presence and incidence or number of ACFs. 相似文献