首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   155154篇
  免费   32948篇
  国内免费   2400篇
耳鼻咽喉   5207篇
儿科学   5688篇
妇产科学   2544篇
基础医学   3952篇
口腔科学   1490篇
临床医学   27392篇
内科学   48151篇
皮肤病学   7522篇
神经病学   15487篇
特种医学   6394篇
外科学   41529篇
综合类   288篇
现状与发展   72篇
一般理论   12篇
预防医学   8048篇
眼科学   3367篇
药学   1360篇
中国医学   12篇
肿瘤学   11987篇
  2024年   526篇
  2023年   4890篇
  2022年   1329篇
  2021年   3519篇
  2020年   6271篇
  2019年   2559篇
  2018年   7787篇
  2017年   7613篇
  2016年   8655篇
  2015年   8631篇
  2014年   15827篇
  2013年   15982篇
  2012年   6112篇
  2011年   6076篇
  2010年   10574篇
  2009年   14391篇
  2008年   6145篇
  2007年   4284篇
  2006年   6706篇
  2005年   3954篇
  2004年   3185篇
  2003年   2110篇
  2002年   2185篇
  2001年   3787篇
  2000年   2991篇
  1999年   3204篇
  1998年   3651篇
  1997年   3464篇
  1996年   3364篇
  1995年   3209篇
  1994年   1941篇
  1993年   1560篇
  1992年   1370篇
  1991年   1402篇
  1990年   1055篇
  1989年   1172篇
  1988年   1010篇
  1987年   849篇
  1986年   885篇
  1985年   712篇
  1984年   546篇
  1983年   520篇
  1982年   512篇
  1981年   402篇
  1980年   360篇
  1979年   306篇
  1978年   330篇
  1977年   396篇
  1975年   278篇
  1972年   303篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
972.
The gold standard for definitive management of symptomatic benign prostatic hypertrophy is transurethral resection of the prostate (TURP). Despite its efficacy, TURP has significant morbidity/mortality concerns such as hemorrhage and transurethral resection syndrome. This is especially worrisome for the medically high-risk patient, but the high rates of retrograde ejaculation found with TURP also pose a problem for young patients. A minimally invasive, outpatient alternative to TURP that has long-term efficacy, low morbidity/mortality, and provides a cost-effective advantage is in high demand. This review article discusses microwave thermotherapy as such an option and reports the long-term experience with the CoreTherm (CoreTherm Operations AB, Sweden) device.  相似文献   
973.
Contact diode laser myringotomy and mitomycin C in children   总被引:1,自引:0,他引:1  
OBJECTIVE: To investigate the use of contact diode laser myringotomy (C-LAM), combined with topical mitomycin C, as an alternative method for prolonged middle ear ventilation in children with otitis media with effusion. STUDY DESIGN AND SETTING: Prospective study at a tertiary care pediatric institution. METHODS: Fifteen children enrolled in the study. Mitomycin C was applied to the intact tympanic membrane in the right ears, whereas saline on the left side was used for controls. C-LAM was then performed in all ears. Outcome measures included healing rate and scarring, ear infection, and long-term audiometric follow-up. RESULTS: There was no significant difference in median healing rate. In each group, the median was between the third and fourth month. Normal hearing thresholds were obtained in all children at 2-year follow-up. CONCLUSION: C-LAM proved to be an effective method for medium-term ventilation, but topical mitomycin C before C-LAM did not prolong patency rate in our patients. No significant complication was encountered at 2-year follow-up.  相似文献   
974.
975.
PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy.  相似文献   
976.
977.
The acromioclavicular joint is a potential source of pain in the shoulder. There are a variety of disorders that can affect this joint, including distal clavicle osteolysis, posttraumatic arthritis, osteoarthritis, and rheumatoid arthritis. Nonoperative treatment for this condition with nonsteroidal medication and activity modification can alleviate the pain. When conservative treatment is exhausted, surgical resection of the distal clavicle is often necessary. Arthroscopic resection of the distal clavicle preserves the acromioclavicular ligaments to prevent postoperative distal clavicle instability. The procedure is performed in either the beach chair or lateral position and requires the use of a shaver, electrocautery, and a burr for soft tissue and debridement and bone resection.  相似文献   
978.
Regeneration of human liver was long suspected to occur. It was proven in animals 100 years ago but could not be demonstrated in man until liver biopsy and modern hepatic tests became available. Structural changes in the regenerating liver mainly concern the arrangement of liver cell plates and the size and appearance of hepatocytic nuclei. A return to normalcy in test results depends on the factors responsible for regeneration since various test results change at different rates. Mass, estimated by imaging procedures, is restored parallel with the return of function. Shape is not restored but the pressure of neighboring organs and structures molds the growing remnant so that it almost resembles the original. Factors regulating regeneration in man are beginning to be recognized as they have been in animals. The hope is that regeneration can be accelerated or that cells can be transplanted to replace those lost.  相似文献   
979.
980.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号