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   4224篇
  免费   286篇
  国内免费   18篇
耳鼻咽喉   83篇
儿科学   211篇
妇产科学   44篇
基础医学   403篇
口腔科学   154篇
临床医学   324篇
内科学   998篇
皮肤病学   92篇
神经病学   316篇
特种医学   188篇
外科学   697篇
综合类   100篇
一般理论   1篇
预防医学   137篇
眼科学   171篇
药学   284篇
中国医学   17篇
肿瘤学   308篇
  2023年   52篇
  2022年   127篇
  2021年   276篇
  2020年   148篇
  2019年   200篇
  2018年   226篇
  2017年   165篇
  2016年   190篇
  2015年   173篇
  2014年   269篇
  2013年   281篇
  2012年   384篇
  2011年   302篇
  2010年   178篇
  2009年   110篇
  2008年   177篇
  2007年   164篇
  2006年   150篇
  2005年   124篇
  2004年   101篇
  2003年   66篇
  2002年   59篇
  2001年   46篇
  2000年   61篇
  1999年   53篇
  1998年   28篇
  1997年   25篇
  1996年   19篇
  1995年   11篇
  1994年   8篇
  1992年   22篇
  1991年   22篇
  1990年   29篇
  1989年   18篇
  1988年   17篇
  1987年   23篇
  1986年   20篇
  1985年   16篇
  1984年   18篇
  1983年   12篇
  1982年   8篇
  1978年   11篇
  1977年   10篇
  1976年   9篇
  1975年   16篇
  1974年   11篇
  1973年   9篇
  1972年   10篇
  1971年   11篇
  1970年   8篇
排序方式: 共有4528条查询结果,搜索用时 15 毫秒
1.
2.
Purpose:To evaluate the rate of compliance and the reasons for loss to follow-up in Indian patients with diabetic macular edema (DME), age-related macular degeneration (AMD), and retinal vein occlusion (RVO) being treated with anti-vascular endothelial growth factor (VEGF) therapy.Methods:This was a retrospective single-center study. Patients with DME, AMD, or RVO were eligible if they initiated anti-VEGF therapy between January 2013 and December 2017. Patients'' data were obtained from hospital electronic records, including the number of injections received, visits, details of follow-up, missed appointments, and reasons for loss to follow-up (>365 days).Results:A total of 648 patients were eligible for the study, of which 334 (51.54%) patients were lost to follow-up. Overall, 343 (64.96%) were males and the overall mean (SD) age was 66.40 (7.44) years. A total of 376 (58.0%) patients had a history of diabetes and 364 (56.2%) patients had a history of hypertension. Further, 127 (38.0), 112 (33.5), and 95 (28.4) had DME, AMD, and RVO, respectively and were lost to follow-up. The most commonly reported reason for loss to follow-up was “non-affordability” (n = 120; 41.1%) followed by “no improvement in vision” (n = 83; 28.4%). “No improvement in vision” (42.2%) and “non-affordability” (37.5%) were higher among patients with DME. No association was found in gender- and treatment-wise distribution of reasons for loss to follow-up.Conclusion:The results showed that around half of the patients with DME, AMD, and RVO were lost to follow-up to intravitreal anti-VEGF therapy, and the most common factors were “non-affordability” and “no improvement in vision.”  相似文献   
3.
Objective: Several biologic therapies are available for the treatment of mild-to-moderate Crohn’s disease (CD). This network meta-analysis (NMA) aimed to assess the comparative efficacy of ustekinumab, adalimumab, vedolizumab and infliximab in the maintenance of clinical response and remission after 1?year of treatment.

Methods: A systematic literature search was performed to identify relevant randomized controlled trials (RCTs). Key outcomes of interest were clinical response (CD activity index [CDAI] reduction of 100 points; CDAI-100) and remission (CDAI score under 150 points; CDAI < 150). A treatment sequence Bayesian NMA was conducted to account for the re-randomization of patients based on different clinical definitions, the lack of similarity of the common comparator for each trial and the full treatment pathway from the induction phase onwards.

Results: Thirteen RCTs were identified. Ustekinumab 90?mg q8w was associated with statistically significant improvement in clinical response relative to placebo and vedolizumab 300?mg. For clinical remission, ustekinumab 90?mg q8w was associated with statistically significant improvement relative to placebo and vedolizumab 300?mg q8w. Findings from sub-population analyses had similar results but were not statistically significant.

Conclusions: The NMA suggest that ustekinumab is associated with the highest likelihood of reaching response or remission at 1?year compared with placebo, adalimumab and vedolizumab. Results should be interpreted with caution because this is a novel methodology; however, the treatment sequence analysis may be the most methodologically sound analysis to derive estimates of comparative efficacy in CD in the absence of head-to-head evidence.  相似文献   

4.
5.
Reported herein is a case of obsessive–compulsive disorder with persistent and distressing musical obsessions along with other symptoms. Advanced source analysis of electroencephalographic data indicated high spectral power over the bifrontal region. The musical symptoms were resistant to pharmacotherapy but there was some reduction in frequency and duration of musical obsessions with thought-stopping technique.  相似文献   
6.
7.
Defects involving the distal leg and foot are frequently encountered following various aetiological factors. Paucity of local tissue causes surgeons to resort to the retrograde peninsular flap, the cross leg flap or the free flap. With specific knowledge of perforators, the fasciocutaneous flap from the calf area can be transferred to the defect in a single stage based on skeletonised distal perforators. The surgical anatomy, flap planning and procedure have been detailed. Nineteen patients were treated during the period 1995 to 2005. The perforators were identified preoperatively by audio Doppler. The flaps were marked and dissected proximal to the defect skeletonising the distal perforators under loupe magnification and transferred to the defect in a single stage. The donor site was skin grafted. Out of 19 cases, 16 flaps healed uneventfully, one flap necrosed completely and in two cases there was marginal necrosis. The cases were followed up for 2-10 years with an average of 6 years. With detailed knowledge of perforators one can safely reconstruct distal moderate-size defects of the lower limb in a single stage, thus having the benefits of free tissue transfer without resorting to microsurgery. This technique has proved to be an advancement in the reconstructive repertoire allowing flaps of non conventional dimensions to be perfused by skeletonised perforators.  相似文献   
8.
9.
A case of congenital erythropoietic porphyria, with corneoscleral ulceration, a rare association in this disorder, was reported. Anterior segment ischemia is believed to play an important role in the etiopathogenesis of corneoscleral ulceration. Remarkable improvement occurred with use of topical heparin drops (500 units/ml).  相似文献   
10.
38 cases of sarcoma of head and neck region were analysed in a retrospective way in relation to age, anatomic location, histological, clinical profile, and surgical approaches. Compared to other types of head and neck neoplasms, such as squamous cell carcinoma, soft tissue sarcomas have low rates of regional metastases. However the biological behaviour of soft tissue sarcoma is more aggressive specially in paediatric age group. In the present series, CT scan was considered as the primary modality of investigation. Surgery generally has been recommended as the primary method of treatment for achieving local control, except in those high-grade tumours arising in sites not amenable to resection. 3-year and 5-year survival rates in this present series 50% and 31.6% respectively.  相似文献   
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