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   10844篇
  免费   831篇
  国内免费   67篇
耳鼻咽喉   120篇
儿科学   261篇
妇产科学   160篇
基础医学   1217篇
口腔科学   280篇
临床医学   1172篇
内科学   1962篇
皮肤病学   99篇
神经病学   908篇
特种医学   583篇
外科学   1979篇
综合类   135篇
一般理论   5篇
预防医学   1056篇
眼科学   163篇
药学   910篇
中国医学   7篇
肿瘤学   725篇
  2023年   45篇
  2022年   98篇
  2021年   263篇
  2020年   162篇
  2019年   243篇
  2018年   299篇
  2017年   231篇
  2016年   239篇
  2015年   296篇
  2014年   410篇
  2013年   533篇
  2012年   830篇
  2011年   746篇
  2010年   428篇
  2009年   357篇
  2008年   578篇
  2007年   645篇
  2006年   558篇
  2005年   591篇
  2004年   521篇
  2003年   505篇
  2002年   431篇
  2001年   131篇
  2000年   117篇
  1999年   160篇
  1998年   121篇
  1997年   101篇
  1996年   101篇
  1995年   86篇
  1994年   98篇
  1993年   77篇
  1992年   88篇
  1991年   84篇
  1990年   89篇
  1989年   106篇
  1988年   102篇
  1987年   96篇
  1986年   87篇
  1985年   75篇
  1984年   96篇
  1983年   75篇
  1982年   55篇
  1981年   65篇
  1980年   51篇
  1979年   54篇
  1978年   65篇
  1977年   54篇
  1976年   64篇
  1974年   56篇
  1973年   60篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
ObjectivesTo fill an empirical gap in the literature by examining changes in quality of care measures occurring when multispecialty clinic systems were acquired by hospital-owned, vertically integrated health care delivery systems in the Twin Cities area.ConclusionsMoving a clinic system into a vertically integrated delivery system resulted in limited increases in quality of care indicators. Caution is warranted when the acquisition causes disruption in referral patterns.  相似文献   
2.
3.
4.
5.
The growth of online support groups has led to an expression effects paradigm within the health communication literature. Although religious support expression is characterized as a typical subdimension of emotional support, we argue that in the context of a life-threatening illness, the inclusion of a religious component creates a unique communication process. Using data from an online group for women with breast cancer, we test a theoretical expression effects model. Results demonstrate that for breast cancer patients, religious support expression has distinct effects from general emotional support messages, which highlights the need to further theorize expression effects along these lines.  相似文献   
6.
7.
8.

Background/purpose

Computed tomography (CT) derived Haller Index (HI) remains the standard for quantifying severity in patient with pectus excavatum (PE). Optical scanning described in literature reports optimistic results and new indices that correlate with HI. This study assessed the feasibility of a handheld White Light Scanner (WLS) to obtain 3D measurements and indices of PE deformity.

Methods

From April 2015–April 2017, WLS scanning was conducted by orthotists during clinical visits. Included were children with PE up to 18?years. Analysis assessed correlation of a WLS-derived severity index, Hebal-Malas Index (HMI), with physician measured PE Depth (PED), and CT-derived HI.

Results

Of 195 participants, 185(94%) patients with PE were scanned and 127(69%) had complete WLS data. For 88 patients undergoing monitoring, HMI correlated with PED (r?=?0.42, p?=?0.004). For 39 patients with pre-operative CT, HMI demonstrated strong correlation with HI (r?=?0.87, p < 0.0001).

Conclusions

WLS demonstrated high feasibility of scanning PE. WLS-derived HMI best correlates with HI for patients with severe pectus deformity. Our current data is suggestive that WLS is best applied for severe deformities and yet to be established for milder deformities. Future yearly WLS will provide data on deformity progression and surgical therapy.

Level of Evidence

IV.

Type of Study

Diagnostic Study.  相似文献   
9.
Lucio phenomenon is an atypical reaction of leprosy, characterized by vasculitic lesions that can mimic antiphospholipid syndrome (APS) clinically. Distinguishing the two can be difficult as antiphospholipid autoantibodies may be present in patients with leprosy. We report on a 32‐year‐old female patient presenting with a sudden onset of fever, hemorrhagic bullae, and skin necrosis on her lower legs. She was treated for APS due to the presence of antiphospholipid antibodies but had an inadequate response. A skin biopsy revealed thrombotic vasculopathy and necrotizing vasculitis associated with aggregation of foam cells in the perivascular area and subcutis, with acid‐fast bacilli in the histiocytes and blood vessel walls. Direct immunofluorescence showed IgM, C3, and fibrinogen deposition in the superficial and deep dermal blood vessels. The pathology confirmed the diagnosis of Lucio phenomenon, and appropriate therapy was given. It is essential to evaluate the patient comprehensively, including clinical, serological, and pathological aspects, to obtain the correct diagnosis.  相似文献   
10.
ABSTRACT

Although exclusive breastfeeding has been linked to lower rates of postnatal HIV transmission compared to nonexclusive breastfeeding, mechanisms underlying this are unclear. Across a longitudinally sampled cohort of South African infants, we showed that exclusively breastfed (EBF) infants had altered gut bacterial communities when compared to nonexclusively breastfed (NEBF) infants, as well as reduced peripheral CD4 + T cell activation and lowered chemokine and chemokine receptor expression in the oral mucosa. We further demonstrated that the relative abundance of key taxa was correlated with peripheral CD4 + T cell activation. Here, we supplement those findings by using compositional data analyses to identify shifts in the abundance of several Bifidobacteria strains relative to select strains of Escherichia, Bacteroides, and others that are associated with the transition to NEBF. We illustrate that the abundance ratio of these taxa is tightly correlated with feeding modality and is a strong predictor of peripheral T cell activation. More broadly, we discuss our study in the context of novel developments and explore future directions for the field.  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