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   1627篇
  免费   131篇
  国内免费   7篇
耳鼻咽喉   30篇
儿科学   68篇
妇产科学   27篇
基础医学   208篇
口腔科学   20篇
临床医学   193篇
内科学   282篇
皮肤病学   27篇
神经病学   238篇
特种医学   136篇
外科学   145篇
综合类   40篇
一般理论   2篇
预防医学   199篇
眼科学   11篇
药学   78篇
中国医学   2篇
肿瘤学   59篇
  2023年   15篇
  2021年   42篇
  2020年   22篇
  2019年   25篇
  2018年   29篇
  2017年   28篇
  2016年   22篇
  2015年   38篇
  2014年   52篇
  2013年   84篇
  2012年   54篇
  2011年   66篇
  2010年   58篇
  2009年   47篇
  2008年   75篇
  2007年   81篇
  2006年   68篇
  2005年   72篇
  2004年   48篇
  2003年   49篇
  2002年   46篇
  2001年   53篇
  2000年   45篇
  1999年   45篇
  1998年   30篇
  1997年   43篇
  1996年   34篇
  1995年   28篇
  1994年   23篇
  1993年   17篇
  1992年   25篇
  1991年   15篇
  1990年   18篇
  1989年   21篇
  1988年   21篇
  1987年   21篇
  1986年   25篇
  1985年   20篇
  1984年   17篇
  1983年   15篇
  1982年   16篇
  1981年   15篇
  1980年   16篇
  1978年   11篇
  1977年   10篇
  1976年   13篇
  1975年   11篇
  1973年   20篇
  1971年   11篇
  1967年   10篇
排序方式: 共有1765条查询结果,搜索用时 10 毫秒
61.
62.
Color Doppler imaging (CDI) can demonstrate the relative direction and velocity of blood flow in color, superimposed on a conventional gray-scale ultrasound image that depicts stationary tissue. Twenty-five infants were studied with portable CDI in the coronal, sagittal, and axial planes. Bilateral antegrade flow was noted in the anterior, middle, and posterior cerebral arteries in all patients. Multiplanar CDI can image flow in the circle of Willis and its tributaries and branches.  相似文献   
63.
Kaplan  PA; Reiskin  AB; Tu  HK 《Radiology》1987,163(1):217-220
Arthrograms of the temporomandibular joint were obtained in 20 symptomatic joints that had previous reconstructive arthroplasty with disk repositioning because of internal derangements. Preoperative arthrograms were available for comparison in 18 joints. Symptoms resulting in a postoperative arthrogram included pain, limited ability to open the mouth, and clicking of the joints. Postoperative arthrographic findings included limited anterior translation of the condyle (90%), irregularity in outline of the intraarticular contrast agent (60%), a conical configuration of the posterior recess (25%), decreased size of the joint (28%), anterior displacement of the meniscus (25%), and perforated meniscus (15%). Many of these findings may have resulted from fibrosis and scarring, which may be a response to intraarticular bleeding. The mechanism by which the fibrosis causes the postsurgical arthrographic features is discussed.  相似文献   
64.
Context/Objective: The study aimed to investigate the presence of a training effect for rehabilitation of walking function in motor-incomplete spinal cord injury (SCI) through daily use of functional electrical stimulation (FES).

Setting: A specialist FES outpatient centre.

Participants: Thirty-five participants (mean age 53, SD 15, range 18-80; mean years since diagnosis 9, range 5 months - 39 years) with drop foot and motor-incomplete SCI (T12 or higher, ASIA Impairment Scale C and D) able to ambulate 10 metres with the use of a walking stick or frame.

Interventions: FES of the peroneal nerve, glutei and hamstrings as clinically indicated over six months in the community.

Outcome Measures: The data was analysed for a training effect (difference between unassisted ten metre walking speed at baseline and after six months) and orthotic effects (difference between walking speed with and without FES) initially on day one and after six months. The data was further analysed for a minimum clinically important difference (MCID) (>0.06 m/s).

Results: A clinically meaningful, significant change was observed for initial orthotic effect (0.13m/s, CI: 0.04-0.17, P?=?0.013), total orthotic effect (0.11m/s, CI: 0.04-0.18, P?=?0.017) and training effect (0.09m/s, CI: 0.02-0.16, P?=?0.025).

Conclusion: The results suggest that daily independent use of FES may produce clinically meaningful changes in walking speed which are significant for motor-incomplete SCI. Further research exploring the mechanism for the presence of a training effect may be beneficial in targeting therapies for future rehabilitation.  相似文献   
65.
66.
We identified a family in Mali with two sisters affected by spastic paraplegia. In addition to spasticity and weakness of the lower limbs, the patients had marked atrophy of the distal upper extremities. Homozygosity mapping using single nucleotide polymorphism arrays showed that the sisters shared a region of extended homozygosity at chromosome 19p13.11-q12 that was not shared by controls. These findings indicate a clinically and genetically distinct form of hereditary spastic paraplegia with amyotrophy, designated SPG43.  相似文献   
67.
68.
Background In acne vulgaris patients, the presence of a dysregulation of the production of innate and specific antimicrobial peptides has been postulated. Objective This study aims to determine whether human neutrophil proteins (HNP) 1–3 are expressed in acne patients. Materials and methods HNP 1–3 expression was investigated in 35 acne patients treated with isotretinoin and in 25 healthy subjects. At the beginning of the study, two skin biopsies were taken from acne patients; one biopsy was taken from an established pustule and one from uninvolved skin, and the biopsies were repeated after treatment. Only one biopsy was obtained from controls. Results The statistical analysis showed that pustular lesions of acne patients had significantly higher levels of perivascular and interstitial HNP 1–3 expression when compared with the biopsy of uninvolved skin of these patients (P = 0.003, P = 0.001, respectively) and with that of healthy controls (P = 0.007, P = 0.014, respectively). Isotretinoin treatment achieved a decrease in the perivascular and interstitial HNP 1–3 expression of pustular lesions (P = 0.01, P = 0.001, respectively). Conclusion Our current study demonstrates the novel observation that a recently identified antimicrobial peptide, HNP 1–3, is expressed in neutrophils of acne inflammation but not in uninvolved skin of these patients. These results suggest that HNP 1–3 may contribute to the development of inflammatory lesions of acne.  相似文献   
69.
70.
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