全文获取类型
收费全文 | 2578篇 |
免费 | 161篇 |
国内免费 | 77篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 216篇 |
妇产科学 | 57篇 |
基础医学 | 351篇 |
口腔科学 | 67篇 |
临床医学 | 285篇 |
内科学 | 629篇 |
皮肤病学 | 77篇 |
神经病学 | 112篇 |
特种医学 | 407篇 |
外科学 | 140篇 |
综合类 | 52篇 |
预防医学 | 136篇 |
眼科学 | 26篇 |
药学 | 118篇 |
2篇 | |
肿瘤学 | 137篇 |
出版年
2023年 | 6篇 |
2022年 | 10篇 |
2021年 | 19篇 |
2020年 | 25篇 |
2019年 | 21篇 |
2018年 | 40篇 |
2017年 | 25篇 |
2016年 | 28篇 |
2015年 | 45篇 |
2014年 | 57篇 |
2013年 | 75篇 |
2012年 | 58篇 |
2011年 | 66篇 |
2010年 | 101篇 |
2009年 | 100篇 |
2008年 | 81篇 |
2007年 | 109篇 |
2006年 | 88篇 |
2005年 | 76篇 |
2004年 | 48篇 |
2003年 | 38篇 |
2002年 | 60篇 |
2001年 | 71篇 |
2000年 | 54篇 |
1999年 | 53篇 |
1998年 | 135篇 |
1997年 | 164篇 |
1996年 | 134篇 |
1995年 | 119篇 |
1994年 | 123篇 |
1993年 | 107篇 |
1992年 | 47篇 |
1991年 | 45篇 |
1990年 | 44篇 |
1989年 | 66篇 |
1988年 | 47篇 |
1987年 | 48篇 |
1986年 | 54篇 |
1985年 | 52篇 |
1984年 | 36篇 |
1983年 | 22篇 |
1982年 | 25篇 |
1981年 | 30篇 |
1980年 | 25篇 |
1979年 | 6篇 |
1978年 | 14篇 |
1977年 | 24篇 |
1976年 | 28篇 |
1975年 | 17篇 |
1972年 | 7篇 |
排序方式: 共有2816条查询结果,搜索用时 0 毫秒
991.
992.
Thirty-five patients with suspected internal derangements of the knee were examined with conventional two-dimensional (2D) spin-echo magnetic resonance (MR) imaging techniques and a new rapid three-dimensional (3D) method called 3D FASTER (field echo acquisition with a short repetition time and echo reduction). A 9-minute 3D FASTER data acquisition achieves nearly isotropic voxels for the calculation of any desired image plane without a significant loss in image quality. Image contrast is optimized for visualization of knee anatomy in a single sequence. An image-processing workstation is used to speed the multiplanar image calculation and display for more efficient analysis of the complex 3D data set. The 3D FASTER images were superior or equal to 2D images (which took three times longer to acquire) in demonstrating meniscal tears, ligament tears, bone marrow disease, and osteochondral defects. The combined advantages of improved imaging capability and efficiency could make 3D FASTER imaging a routine MR method for knee imaging. 相似文献
993.
Bladder diverticula in children 总被引:3,自引:0,他引:3
994.
MR imaging in acute infectious cellulitis 总被引:5,自引:0,他引:5
995.
996.
Hepatic adenoma: MR findings in 51 pathologically proved lesions 总被引:15,自引:0,他引:15
Arrive L; Flejou JF; Vilgrain V; Belghiti J; Najmark D; Zins M; Menu Y; Tubiana JM; Nahum H 《Radiology》1994,193(2):507
997.
998.
Despite the wide use of fentanyl for analgesia in newborns, concerns have been raised about potential haemodynamic side-effects. Since sick newborns may lose their cerebral blood flow autoregulation, a drug-induced haemodynamic instability could lead to brain injury. We assessed the effects of a 15-min infusion of fentanyl (3μg/kg) on the general and cerebral haemodynamics in I5 newborns (median gestational age 29 weeks, 25th–75th percentile, range 28–31 weeks; birthweight 1170 g. range 955–1790 g). The heart rate and mean arterial blood pressure were continuously recorded. Mean cerebral blood flow velocity and pulsatility index were measured using pulsed Doppler ultrasound before, during and up to 60 min after the onset of fentanyl administration. No significant modification of general or cerebral haemodynamics was observed. In conclusion, the infusion or 3μg/kg of fentanyl did not lead to any deleterious effect on the general or cerebral haemodynamics in sick normovolaemic newborns. 相似文献
999.
JM Echevarria ; P Leon ; CJ Domingo ; JA Lopez ; C Elola ; M Madurga ; F Salmeron ; PL Yap ; J Daub ; P Simmonds 《Transfusion》1996,36(8):725-730
BACKGROUND: Passive transfer of antibody to hepatitis C virus (HCV) has been thought to occur after infusion of human intravenous immunoglobulin (IVIG), as anti-HCV and/or HCV RNA was commonly found in that product. Recently, however, HCV RNA was detected in the serum of recipients of IVIG. Establishment of a causal relationship between IVIG therapy and HCV infection in recipients was attempted. STUDY DESIGN AND METHODS: Anti-HCV and HCV RNA sequences were investigated in serum samples from 39 persons who received a human IVIG product in seven different hospitals in Spain. HCV RNA was also investigated in two batches of the IVIG shared by some recipients. All the viral RNA detected were characterized with a line probe assay, restriction fragment length polymorphism analysis of the 5'-noncoding and core regions, and sequencing of the nonstructural 5 region. RESULTS: On the basis of both clinical and laboratory data, a relationship could be established between the IVIG therapy and the acquisition of the HCV infection by the recipients. Several HCV strains were detected among the recipients, with most of the recipients coming from the same hospital presenting with closely related strains. Moreover, an HCV strain almost identical to the main strain detected among the recipients was found in one batch of the IVIG that probably was shared by most of them. Follow-up studies and evaluation of low-avidity anti- HCV IgG suggested that both acute primary infections and reinfections were produced. In one case, direct evidence of reinfection by a different HCV strain was obtained. CONCLUSION: The results did not exclude the possibility that a second HCV strain associated with a further, unidentified batch of the IVIG could have contributed to this outbreak. 相似文献
1000.