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   2476篇
  免费   155篇
  国内免费   9篇
耳鼻咽喉   53篇
儿科学   137篇
妇产科学   36篇
基础医学   367篇
口腔科学   26篇
临床医学   183篇
内科学   528篇
皮肤病学   28篇
神经病学   197篇
特种医学   59篇
外科学   257篇
综合类   40篇
一般理论   1篇
预防医学   227篇
眼科学   85篇
药学   224篇
中国医学   4篇
肿瘤学   188篇
  2023年   18篇
  2022年   38篇
  2021年   102篇
  2020年   70篇
  2019年   76篇
  2018年   106篇
  2017年   61篇
  2016年   75篇
  2015年   80篇
  2014年   104篇
  2013年   136篇
  2012年   197篇
  2011年   171篇
  2010年   110篇
  2009年   96篇
  2008年   155篇
  2007年   132篇
  2006年   125篇
  2005年   127篇
  2004年   112篇
  2003年   105篇
  2002年   91篇
  2001年   31篇
  2000年   32篇
  1999年   30篇
  1998年   23篇
  1997年   14篇
  1996年   12篇
  1995年   10篇
  1994年   7篇
  1993年   5篇
  1992年   19篇
  1991年   17篇
  1990年   15篇
  1989年   15篇
  1988年   14篇
  1987年   11篇
  1986年   12篇
  1985年   7篇
  1984年   9篇
  1983年   6篇
  1981年   4篇
  1980年   3篇
  1979年   14篇
  1978年   8篇
  1977年   4篇
  1973年   4篇
  1971年   3篇
  1970年   4篇
  1965年   2篇
排序方式: 共有2640条查询结果,搜索用时 15 毫秒
61.
62.
A 72‐year‐old woman with a history of paroxysmal atrial fibrillation (AF) and sinus node dysfunction is seen in clinic for routine follow‐up.  相似文献   
63.
Inclusion body myositis is a rare sporadic inflammatory‐degenerative myopathy of the elderly. Despite being the commonest type of acquired myopathy after the age of 50, misdiagnosis is extremely common. The most frequent hurdle in identifying new cases is the wrong diagnosis of polymyositis or motor neuron disease. Novel insights into pathogenic mechanisms have heralded the quest for newer therapeutics as well as drug repurposing in this otherwise progressive disorder.  相似文献   
64.
65.
Increased physical activity (PA) is associated with improvement of cardiac risk factors and prevention of cardiovascular disease, yet many women remain sedentary. With rising Internet use, Web-based interventions provide an alternative to improve PA, but their effectiveness for change in PA and quality of life (QOL) in a real-world setting is unknown. Participants were United States women ≥18 years old who received 12 weekly PA modules and completed surveys on PA, QOL, and readiness for PA at registration (registration cohort, n = 3,796) or registration and 12 weeks (evaluation cohort, n = 892). QOL was assessed with a modified Short Form-36 with subscores for energy and well-being. Participants showed significant (p <0.001) favorable changes in PA (baseline, median 240 kcal/week, interquartile range 62 to 667; 12 weeks, 343 kcal/week, 131 to 828), stage of readiness for PA, and body mass index (baseline, 29.3 kg/m(2), 24.9 to 34.7; 12 weeks, 28.9 kg/m(2), 24.6 to 34.2). Significant improvements (p <0.0001) were also found in composite scores for energy and well-being. Compliance with PA guideline recommendations increased from 15.8% to 21.4%. Program weeks completed (p = 0.03), energy (p = 0.04), and well-being (p = 0.002) were significantly associated with achieving guideline compliance. In women reporting no PA at baseline (n = 88), program participation resulted in 54.6% achieving some PA and another 9.1% achieving total compliance with recommendations. In conclusion, in this national cohort of women, a 12-week Web-based intervention improved PA and QOL measurements, resulting in higher short-term PA guideline compliance and better QOL. Increasing use of this simple Web-based tool could improve PA and promote disease prevention.  相似文献   
66.
Inflammaging refers to a low-grade pro-inflammatory phenotype which accompanies aging in mammals. The aging process is associated with a decline in autophagic capacity which impairs cellular housekeeping, leading to protein aggregation and accumulation of dysfunctional mitochondria which provoke reactive oxygen species (ROS) production and oxidative stress. Recent studies have clearly indicated that the ROS production induced by damaged mitochondria can stimulate intracellular danger-sensing multiprotein platforms called inflammasomes. Nod-like receptor 3 (NLRP3) can be activated by many danger signals, e.g. ROS, cathepsin B released from destabilized lysosomes and aggregated proteins, all of which evoke cellular stress and are involved in the aging process. NLRP3 activation is also enhanced in many age-related diseases, e.g. atherosclerosis, obesity and type 2 diabetes. NLRP3 activates inflammatory caspases, mostly caspase-1, which cleave the inactive precursors of IL-1β and IL-18 and stimulate their secretion. Consequently, these cytokines provoke inflammatory responses and accelerate the aging process by inhibiting autophagy. In conclusion, inhibition of autophagic capacity with aging generates the inflammaging condition via the activation of inflammasomes, in particular NLRP3. We will provide here a perspective on the current research of the ROS-dependent activation of inflammasomes triggered by the decline in autophagic cleansing of dysfunctional mitochondria.  相似文献   
67.
An experimental, single-subject research study investigated the comparative efficacy of the Picture Exchange Communication System (PECS) versus a speech-generating device (SGD) in developing requesting skills for three elementary-age children with severe autism and little to no functional speech. Results demonstrated increases in requesting behavior for all participants across intervention phases with both augmentative and alternative communication (AAC) intervention strategies; however, difficulties were observed with picture discrimination. The Wilcoxon signed pair test did not reveal significant differences between PECS and the SGD for any participant. Findings suggest PECS and SGD are equally appropriate for developing initial requesting skills. Based on the current findings, successful implementation of either AAC strategy is achievable when appropriate instructional strategies are used.  相似文献   
68.

Background:

The presence of extra articular deformities either in the femur or the tibia with arthritis of the knee makes total knee arthroplasty (TKA) technically demanding. The purpose of this study is to report outcomes with Total Knee Arthroplasty in patients with arthritis of the knee associated with extra articular deformity by intraarticular resection and soft tissue balancing.

Materials and Methods:

Thirty six knees (32 patients) who had arthritis of the knee associated with extra articular deformity, underwent total knee arthroplasty between 1999 and 2006 were included in this retrospective analysis. All patients had intraarticular resection with soft tissue balancing to correct the deformity. Full length weight bearing anteroposterior X-rays, Knee society scores, and Knee range of motion was recorded pre- and postoperatively.

Results:

The mean period of followup was 85 months (range 42-120 months). The deformities amenable to correction by intraarticular resection in our series were Femur- Coronal plane 11°-18° (mean 16.2°) Saggital plane 0°-15° (mean 10.1°) Tibia - Coronal plane 12°-24° (mean 21°). There was an improvement in the range of motion from mean of 54° preoperatively to 114° postoperatively (P value < 0.05). The Knee Society- Knee Score improved from 37 points to 85 points postoperatively (P value < 0.05). The functional score improved from a mean value of 19 to a mean of 69.5 at followup (P < 0.01). The preoperative hip knee ankle angle in the coronal plane improved from a mean of 14° ± 2° varus (26° varus to 4° valgus) to a mean of 2° ± 0.6° varus (6° varus to 2° valgus).

Conclusion:

With a good preoperative planning and templating, intraarticular bone resection and good soft tissue balancing both in flexion and extension, correction would be possible in majority of extraarticular deformities.  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