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   12696篇
  免费   893篇
  国内免费   204篇
耳鼻咽喉   309篇
儿科学   120篇
妇产科学   180篇
基础医学   2001篇
口腔科学   171篇
临床医学   938篇
内科学   2720篇
皮肤病学   489篇
神经病学   1032篇
特种医学   808篇
外科学   1634篇
综合类   154篇
预防医学   445篇
眼科学   257篇
药学   1134篇
  1篇
中国医学   151篇
肿瘤学   1249篇
  2023年   61篇
  2022年   49篇
  2021年   482篇
  2020年   218篇
  2019年   365篇
  2018年   443篇
  2017年   347篇
  2016年   544篇
  2015年   717篇
  2014年   858篇
  2013年   921篇
  2012年   1298篇
  2011年   1160篇
  2010年   770篇
  2009年   614篇
  2008年   826篇
  2007年   748篇
  2006年   525篇
  2005年   574篇
  2004年   458篇
  2003年   387篇
  2002年   351篇
  2001年   136篇
  2000年   100篇
  1999年   85篇
  1998年   49篇
  1997年   57篇
  1996年   39篇
  1995年   35篇
  1994年   35篇
  1993年   27篇
  1992年   49篇
  1991年   44篇
  1990年   31篇
  1989年   22篇
  1988年   37篇
  1987年   35篇
  1986年   22篇
  1985年   17篇
  1984年   16篇
  1983年   12篇
  1981年   12篇
  1980年   13篇
  1977年   13篇
  1976年   14篇
  1973年   11篇
  1972年   23篇
  1970年   16篇
  1968年   11篇
  1967年   12篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
TL1A is a TNF‐like cytokine which has been shown to co‐stimulate TH1 and TH17 responses during chronic inflammation. The expression of this novel cytokine has been investigated in inflammatory disorders like rheumatoid arthritis and inflammatory bowel disease, but little is known about expression and induction in psoriasis. Indeed, the pathogenesis in psoriasis is still not fully understood and it is speculated that cytokines other than TNF‐α are important in subsets of patients. Also, for patients with severe disease that are treated with systemic anti‐TNF‐α blockade, novel candidates to be used as disease and response biomarkers are of high interest. Here, we demonstrate TL1A expression in biopsies from psoriatic lesions. Also, we investigated spontaneous and induced TL1A secretion from PBMCs and blood levels from a cohort of psoriasis patients. Here, increased spontaneous secretion from PBMCs was observed as compared to healthy controls and a small subset of patients had highly elevated TL1A in the blood. Interestingly, activation of PBMCs with various cytokines showed a decreased sensitivity for TL1A activation in psoriasis patients compared to healthy controls.TL1A levels in blood and biopsies could not be correlated with disease activity with this patient cohort. Thus, additional large‐scale studies are warranted to investigate TL1A as a biomarker.  相似文献   
3.

Objective

The advantage of arteriovenous fistulas (AVFs) in older patients requiring dialysis is controversial. We reviewed our vascular access experience in patients ≥70 years of age (older group) compared with younger patients.

Methods

We analyzed consecutive patients who underwent access surgery between 2013 and 2016. Primary success (PS) and primary patency (PP) data were analyzed between the older and younger groups before and after propensity score matching of the patients' characteristics and access composition. PS was defined as the achievement of access function that was amenable to two sessions of successful cannulation without early occlusion or maturation failure requiring revision. PP was defined as the time with uninterrupted patency without intervention.

Results

A total of 594 consecutive accesses were created among 563 patients, of whom 119 were allocated into each group after propensity score matching. In the whole cohort, 193 accesses (32.5%) were performed in older patients. AVFs were performed in 130 (67.4%) older patients and 293 (73.1%) younger patients. Regarding AVFs, the PS rate (83.6% in the older group vs 94.3% in the younger group; P = .001) and the overall PP at 6 and 12 months (73.1% and 57.1%, respectively, in the older group vs 86.7% and 77.7%, respectively, in the younger group; P = .009) were lower in the older group than in the younger group. However, no differences were found in the PS and PP rates for arteriovenous grafts between groups. Regarding the AVF location, the PS rate for forearm AVFs was significantly lower in the older group than in the younger group (76% vs 93%; P < .001); however, the PS rate of the upper arm was not different between the groups (94% vs 97%; P = .425). In the patients with PS, the PP rate of AVFs was similar between the two groups. In the older group with forearm AVFs, the median diameter of the radial artery was larger in the patients with PS than in the patients without PS (2.20 mm with PS vs 2.00 mm without PS; P = .008). The propensity score matching results demonstrated similar trends for the whole cohort, with lower PS (P = .042) and PP rates (P = .023) for AVF in the older group.

Conclusions

The outcomes after AVF were poorer in the older group than in the younger group, which was primarily due to unsatisfactory outcomes in patients with forearm AVFs. Thus, stricter criteria, especially regarding the radial artery diameter, should be applied for forearm AVFs in older patients, and additional research is necessary to delineate the risk factors for primary failure.  相似文献   
4.

Background

In Leriche syndrome, postoperative graft thrombosis remains one of the most significant clinical challenges.

Methods

We reviewed 51 patients who underwent surgery for aortoiliac occlusive disease at our hospital from January 2007 to December 2014. The factors associated with graft patency were determined using the Cox proportional hazard model.

Results

The 2-year prosthetic graft patency rate was 72.5%. Younger age (p = 0.017, Odd ratio (OR) = 1.112), postoperative uncontrolled hypertension (p = 0.044, OR = 3.797), and associated Trans Atlantic Inter-Society Consensus for the Management of Peripheral Arterial Disease II (TASC II) D femoropopliteal lesion (p = 0.008, OR = 11.139) were significantly related factors for prosthetic graft patency after surgical repair. The existing comorbidities of the patients that indicated the need for axillo-bifemoral bypass seemed to be related to lower graft patency or other complications.

Conclusions

For better graft patency after an open surgical repair of Leriche syndrome, strict postoperative hypertension control and distal run-off resolution are necessary.  相似文献   
5.
6.
7.
8.
9.
10.
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