全文获取类型
收费全文 | 7039篇 |
免费 | 691篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 103篇 |
儿科学 | 230篇 |
妇产科学 | 175篇 |
基础医学 | 963篇 |
口腔科学 | 134篇 |
临床医学 | 685篇 |
内科学 | 1379篇 |
皮肤病学 | 80篇 |
神经病学 | 769篇 |
特种医学 | 428篇 |
外科学 | 958篇 |
综合类 | 133篇 |
一般理论 | 5篇 |
预防医学 | 692篇 |
眼科学 | 40篇 |
药学 | 395篇 |
中国医学 | 1篇 |
肿瘤学 | 566篇 |
出版年
2021年 | 107篇 |
2019年 | 93篇 |
2018年 | 97篇 |
2017年 | 82篇 |
2016年 | 98篇 |
2015年 | 95篇 |
2014年 | 158篇 |
2013年 | 203篇 |
2012年 | 294篇 |
2011年 | 300篇 |
2010年 | 191篇 |
2009年 | 180篇 |
2008年 | 301篇 |
2007年 | 324篇 |
2006年 | 287篇 |
2005年 | 307篇 |
2004年 | 288篇 |
2003年 | 276篇 |
2002年 | 251篇 |
2001年 | 247篇 |
2000年 | 243篇 |
1999年 | 239篇 |
1998年 | 74篇 |
1997年 | 75篇 |
1996年 | 71篇 |
1995年 | 57篇 |
1992年 | 140篇 |
1991年 | 174篇 |
1990年 | 180篇 |
1989年 | 172篇 |
1988年 | 140篇 |
1987年 | 147篇 |
1986年 | 133篇 |
1985年 | 153篇 |
1984年 | 112篇 |
1983年 | 98篇 |
1982年 | 64篇 |
1981年 | 62篇 |
1980年 | 59篇 |
1979年 | 86篇 |
1978年 | 68篇 |
1977年 | 65篇 |
1976年 | 64篇 |
1975年 | 61篇 |
1974年 | 78篇 |
1973年 | 74篇 |
1972年 | 67篇 |
1971年 | 61篇 |
1969年 | 65篇 |
1968年 | 49篇 |
排序方式: 共有7736条查询结果,搜索用时 203 毫秒
41.
Posterior chamber intraocular lens implantation in the absence of posterior capsular support 总被引:1,自引:0,他引:1
Because of the high incidence and great variety of complications associated with anterior chamber intraocular lenses, we have developed a technique for the implantation of a posterior chamber intraocular lens in the absence of posterior capsular support. The posterior chamber IOL is placed in the ciliary sulcus by suturing the superior haptic to the iris and the inferior haptic to the sclera at the ciliary sulcus. We have used this technique successfully in both complicated extracapsular surgery and secondary intraocular lens implantation. 相似文献
42.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
43.
Physicians, vital statistics, and disease reporting 总被引:1,自引:0,他引:1
44.
45.
The chest radiographs obtained in nine patients with acquired immunodeficiency syndrome (AIDS) and pulmonary toxoplasmosis were reviewed. In three patients, a bilateral, diffuse, fine to medium reticulonodular pattern indistinguishable from that seen in Pneumocystis carinii pneumonia (PCP) was observed. In six patients, however, a bilateral, predominantly coarse, nodular pattern was observed. This type of abnormality is unusual with PCP, and its presence may help in distinguishing between pulmonary infections caused by Toxoplasma gondii and P carinii. Other opportunistic pneumonias occurring in patients with AIDS, including tuberculosis, histoplasmosis, and coccidioidomycosis, might show similar coarse, nodular opacities on chest radiographs and thus may not be differentiated from pulmonary toxoplasmosis. No hilar or mediastinal adenopathy was observed. Two patients had pleural fluid. Radiologists familiar with the chest radiographic appearance of T gondii pneumonia could be first to suggest this unusual complication of AIDS. 相似文献
46.
47.
Mechanoregulation of human articular chondrocyte aggrecan and type II collagen expression by intermittent hydrostatic pressure in vitro. 总被引:6,自引:0,他引:6
48.
49.
M P Joseph M L Goodman B Z Pilch F R Bieber L B Holmes E Reardon 《Head & neck surgery》1986,8(6):456-462
Heterotopic cervical salivary gland tissue was found in a 4-yr-old girl with branchial and otologic abnormalities. Her mother and sister also had heterotopic cervical salivary tissue in association with anomalies that suggest the branchio-otorenal (BOR) syndrome. Heterotopic cervical salivary gland tissue may result from abnormal branchial development. 相似文献
50.
Timothy R. McAdams Karl R. Knudsen Naveen Yalamanchi James Chang Stuart B. Goodman 《Knee surgery, sports traumatology, arthroscopy》2007,15(9):1144-1149
The purpose of this study was to compare the histological characteristics of an autogenous fascia lata graft alone and a fascia
lata graft combined with a deltoid flap in the reconstruction of rotator cuff tears. Ten New Zealand white rabbits were divided
into two groups. Infraspinatus tendon defects (1 × 1 cm) were created in each animal. Reconstruction consisted of either a
fascia lata graft alone or a fascia lata graft combined with a distally based deltoid flap. At 3 months, tissue harvest and
histological analysis was performed. Compared to the fascia lata graft alone, there was significantly increased remodeling
activity and neovascularization in the group that included a deltoid flap. Also, there was pronounced interdigitation at the
graft/flap interface in the latter group. A mutually beneficial relationship may exist when an autogenous fascial graft is
combined with a functional deltoid flap for reconstructing large rotator cuff defects. 相似文献