全文获取类型
收费全文 | 3210篇 |
免费 | 148篇 |
国内免费 | 79篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 191篇 |
妇产科学 | 43篇 |
基础医学 | 295篇 |
口腔科学 | 65篇 |
临床医学 | 306篇 |
内科学 | 1168篇 |
皮肤病学 | 77篇 |
神经病学 | 128篇 |
特种医学 | 461篇 |
外科学 | 236篇 |
综合类 | 52篇 |
预防医学 | 108篇 |
眼科学 | 20篇 |
药学 | 117篇 |
2篇 | |
肿瘤学 | 156篇 |
出版年
2023年 | 8篇 |
2022年 | 4篇 |
2021年 | 32篇 |
2020年 | 22篇 |
2019年 | 35篇 |
2018年 | 56篇 |
2017年 | 29篇 |
2016年 | 33篇 |
2015年 | 55篇 |
2014年 | 97篇 |
2013年 | 101篇 |
2012年 | 96篇 |
2011年 | 103篇 |
2010年 | 114篇 |
2009年 | 112篇 |
2008年 | 99篇 |
2007年 | 160篇 |
2006年 | 110篇 |
2005年 | 123篇 |
2004年 | 93篇 |
2003年 | 75篇 |
2002年 | 96篇 |
2001年 | 82篇 |
2000年 | 81篇 |
1999年 | 63篇 |
1998年 | 140篇 |
1997年 | 167篇 |
1996年 | 136篇 |
1995年 | 116篇 |
1994年 | 120篇 |
1993年 | 104篇 |
1992年 | 48篇 |
1991年 | 55篇 |
1990年 | 64篇 |
1989年 | 79篇 |
1988年 | 71篇 |
1987年 | 55篇 |
1986年 | 66篇 |
1985年 | 63篇 |
1984年 | 37篇 |
1983年 | 25篇 |
1982年 | 33篇 |
1981年 | 35篇 |
1980年 | 27篇 |
1979年 | 10篇 |
1978年 | 15篇 |
1977年 | 21篇 |
1976年 | 27篇 |
1975年 | 17篇 |
1974年 | 7篇 |
排序方式: 共有3437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.
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.
The cognit: a network model of cortical representation. 总被引:4,自引:0,他引:4
Joaquín M Fuster 《International journal of psychophysiology》2006,60(2):125-132
The prevalent concept in modular models is that there are discrete cortical domains dedicated more or less exclusively to such cognitive functions as visual discrimination, language, spatial attention, face recognition, motor programming, memory retrieval, and working memory. Most of these models have failed or languished for lack of conclusive evidence. In their stead, network models are emerging as more suitable and productive alternatives. Network models are predicated on the basic tenet that cognitive representations consist of widely distributed networks of cortical neurons. Cognitive functions, namely perception, attention, memory, language, and intelligence, consist of neural transactions within and between these networks. The present model postulates that memory and knowledge are represented by distributed, interactive, and overlapping networks of neurons in association cortex. Such networks, named cognits, constitute the basic units of memory or knowledge. The association cortex of posterior-post-rolandic-regions contains perceptual cognits: cognitive networks made of neurons associated by information acquired through the senses. Conversely, frontal association cortex contains executive cognits, made of neurons associated by information related to action. In both posterior and frontal cortex, cognits are hierarchically organized. At the bottom of that organization-that is, in parasensory and premotor cortex-cognits are small and relatively simple, representing simple percepts or motor acts. At the top of the organization-in temporo-parietal and prefrontal cortex-cognits are wider and represent complex and abstract information of perceptual or executive character. Posterior and frontal networks are associated by long reciprocal cortico-cortical connections. These connections support the dynamics of the perception-action cycle in sequential behavior, speech, and reasoning. 相似文献