全文获取类型
收费全文 | 5204篇 |
免费 | 367篇 |
国内免费 | 79篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 325篇 |
妇产科学 | 80篇 |
基础医学 | 497篇 |
口腔科学 | 85篇 |
临床医学 | 617篇 |
内科学 | 830篇 |
皮肤病学 | 91篇 |
神经病学 | 309篇 |
特种医学 | 545篇 |
外科学 | 461篇 |
综合类 | 75篇 |
预防医学 | 360篇 |
眼科学 | 839篇 |
药学 | 184篇 |
2篇 | |
肿瘤学 | 336篇 |
出版年
2021年 | 59篇 |
2020年 | 40篇 |
2019年 | 71篇 |
2018年 | 81篇 |
2017年 | 70篇 |
2016年 | 61篇 |
2015年 | 90篇 |
2014年 | 106篇 |
2013年 | 174篇 |
2012年 | 185篇 |
2011年 | 220篇 |
2010年 | 168篇 |
2009年 | 166篇 |
2008年 | 173篇 |
2007年 | 225篇 |
2006年 | 210篇 |
2005年 | 221篇 |
2004年 | 187篇 |
2003年 | 148篇 |
2002年 | 148篇 |
2001年 | 151篇 |
2000年 | 149篇 |
1999年 | 100篇 |
1998年 | 158篇 |
1997年 | 175篇 |
1996年 | 160篇 |
1995年 | 125篇 |
1994年 | 135篇 |
1993年 | 120篇 |
1992年 | 103篇 |
1991年 | 106篇 |
1990年 | 92篇 |
1989年 | 114篇 |
1988年 | 99篇 |
1987年 | 107篇 |
1986年 | 101篇 |
1985年 | 111篇 |
1984年 | 79篇 |
1983年 | 45篇 |
1982年 | 54篇 |
1981年 | 51篇 |
1980年 | 52篇 |
1979年 | 45篇 |
1978年 | 42篇 |
1977年 | 47篇 |
1976年 | 46篇 |
1975年 | 37篇 |
1974年 | 24篇 |
1968年 | 22篇 |
1966年 | 21篇 |
排序方式: 共有5650条查询结果,搜索用时 15 毫秒
1.
2.
Jerry A. Shields Ralph C. Eagle Jr Carol L Shields Brian P. Marr 李学民 《美国医学会眼科杂志(中文版)》2006,18(1):33-39
众所周知,视网膜星形细胞瘤常伴有结节性硬化的表现。视网膜星形细胞瘤一般是发生在视网膜神经纤维层的无蒂轻度隆起性病变。临床上可以是单侧发生,也可以是双侧发生。可以单个病灶,也可以多个病灶。可以是透明的,也可以是不透明的。可以有钙化,也可以没有钙化。视网膜星形细胞瘤相对固定的伴有眼内结节性硬化,很少表现为浸润性增长。在很少的情况下视网膜星形细胞瘤可以表现出浸润性增长,造成局部严重并发症。 相似文献
3.
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
4.
5.
In a prospective, randomized, single-masked, cross-over study, 18 patients with primary open-angle glaucoma were treated for one month with each of the following regimens: timolol 0.5% twice daily, timolol 0.5% plus dipivefrin 0.1% twice daily given ten minutes apart, and timolol 0.5% plus dipivefrin 0.1% given twice daily four hours apart. An eight-hour intraocular pressure curve was obtained before treatment and at the end of each monthly regimen. When added to timolol therapy, dipivefrin produced a small but statistically significant additional mean decrease in intraocular pressure. The difference in intraocular pressure reduction between the two regimens for combined timolol and dipivefrin therapy was not statistically significant. 相似文献
6.
Brain morphology in first-episode schizophrenic-like psychotic patients: a quantitative magnetic resonance imaging study 总被引:5,自引:0,他引:5
L E DeLisi A L Hoff J E Schwartz G W Shields S N Halthore S M Gupta F A Henn A K Anand 《Neuropsychopharmacology》1991,29(2):159-175
Brain morphology was examined using magnetic resonance imaging in 30 first-episode patients with a schizophreniclike psychosis, 15 chronic schizophrenics, and 20 neurological controls. Statistical analyses of computer-generated measurements of regions of interest were controlled for gender, age, social class, and total brain volume. Lateral ventricular size was increased in both first-episode and chronic schizophrenic patients, with greater significance on the left than on the right side. Only the chronic patients, however, had reduced temporal lobe size, which also was greater on the left side. No major correlations of regional brain morphological measurements with cognitive functioning were found, although some measurements of verbal memory were correlated with parahippocampal size. This is a report of a preliminary study that suggests that some morphological brain changes may be present at the time of first treatment for a psychotic illness, whereas others may occur later in the course of illness. Future prospective studies may determine the clinical significance of these changes and whether they progress with the development of illness chronicity. 相似文献
7.
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
8.
9.
10.
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