收费全文 | 1381篇 |
免费 | 97篇 |
国内免费 | 10篇 |
耳鼻咽喉 | 6篇 |
儿科学 | 21篇 |
妇产科学 | 39篇 |
基础医学 | 186篇 |
口腔科学 | 66篇 |
临床医学 | 159篇 |
内科学 | 260篇 |
皮肤病学 | 32篇 |
神经病学 | 215篇 |
特种医学 | 40篇 |
外科学 | 157篇 |
综合类 | 11篇 |
预防医学 | 109篇 |
眼科学 | 25篇 |
药学 | 89篇 |
中国医学 | 5篇 |
肿瘤学 | 68篇 |
2024年 | 3篇 |
2023年 | 26篇 |
2022年 | 35篇 |
2021年 | 50篇 |
2020年 | 31篇 |
2019年 | 58篇 |
2018年 | 62篇 |
2017年 | 34篇 |
2016年 | 56篇 |
2015年 | 41篇 |
2014年 | 61篇 |
2013年 | 88篇 |
2012年 | 109篇 |
2011年 | 118篇 |
2010年 | 80篇 |
2009年 | 53篇 |
2008年 | 97篇 |
2007年 | 82篇 |
2006年 | 62篇 |
2005年 | 72篇 |
2004年 | 52篇 |
2003年 | 43篇 |
2002年 | 28篇 |
2001年 | 11篇 |
2000年 | 10篇 |
1999年 | 7篇 |
1998年 | 7篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 6篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1986年 | 3篇 |
1983年 | 2篇 |
1982年 | 6篇 |
1980年 | 3篇 |
1978年 | 3篇 |
1977年 | 6篇 |
1976年 | 5篇 |
1973年 | 2篇 |
1972年 | 4篇 |
1969年 | 5篇 |
1968年 | 9篇 |
1967年 | 5篇 |
1959年 | 2篇 |
1957年 | 3篇 |
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Purpose
Degenerative spondylolisthesis (DS) in the setting of symptomatic lumbar spinal stenosis is commonly treated with spinal fusion in addition to decompression with laminectomy. However, recent studies have shown similar clinical outcomes after decompression alone, suggesting that a subset of DS patients may not require spinal fusion. Identification of dynamic instability could prove useful for predicting which patients are at higher risk of post-laminectomy destabilization necessitating fusion. The goal of this study was to determine if static clinical radiographs adequately characterize dynamic instability in patients with lumbar degenerative spondylolisthesis (DS) and to compare the rotational and translational kinematics in vivo during continuous dynamic flexion activity in DS versus asymptomatic age-matched controls.Methods
Seven patients with symptomatic single level lumbar DS (6 M, 1 F; 66 ± 5.0 years) and seven age-matched asymptomatic controls (5 M, 2 F age 63.9 ± 6.4 years) underwent biplane radiographic imaging during continuous torso flexion. A volumetric model-based tracking system was used to track each vertebra in the radiographic images using subject-specific 3D bone models from high-resolution computed tomography (CT). In vivo continuous dynamic sagittal rotation (flexion/extension) and AP translation (slip) were calculated and compared to clinical measures of intervertebral flexion/extension and AP translation obtained from standard lateral flexion/extension radiographs.Results
Static clinical radiographs underestimate the degree of AP translation seen on dynamic in vivo imaging (1.0 vs 3.1 mm; p = 0.03). DS patients demonstrated three primary motion patterns compared to a single kinematic pattern in asymptomatic controls when analyzing continuous dynamic in vivo imaging. 3/7 (42%) of patients with DS demonstrated aberrant mid-range motion.Conclusion
Continuous in vivo dynamic imaging in DS reveals a spectrum of aberrant motion with significantly greater kinematic heterogeneity than previously realized that is not readily seen on current clinical imaging.Level of evidence
Level V dataGraphical abstract
![点击此处可从《Arthritis care & research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Objective
To develop and test a hybrid measure of muscle strength for juvenile dermatomyositis (JDM), which is based on the combination of the Manual Muscle Testing in 8 muscles (MMT‐8) and the Childhood Myositis Assessment Scale (CMAS) but is more comprehensive than the former and more feasible than the latter.Methods
The hybrid MMT‐8/CMAS (hMC) is composed of all 8 items of the MMT‐8 and 3 items of the CMAS: time of head lift, assessment of abdominal muscles, and floor rise. The score ranges 0–100, with 100 indicating normal muscle strength. Validation procedures were conducted using 3 large multinational patient samples, including a total of 810 JDM patients.Results
The hMC revealed face and content validity, good construct validity, excellent test–retest reliability (intraclass correlation coefficient = 0.99), and internal consistency (Cronbach's α = 0.94), strong responsiveness to clinical change over time (standardized response mean = 0.8 among patients judged as improved by the caring physician), and satisfactory capacity to discriminate patients judged as being in the states of inactive disease or low, moderate, or high disease activity by the physician (P < 0.001) or patients whose parents were satisfied or not satisfied with the illness course (P < 0.001).Conclusion
The hMC was found to possess good measurement properties in a large population of patients with a wide range of disease activity and severity. The new tool, which is primarily intended for use in routine clinical care, should be further tested in other populations of patients evaluated prospectively.Background and objectives
Inappropriate medication use is common in the care of patients with CKD. The feasibility of a simple mobile health tool designed to advise patients on safe medication usage in CKD was examined.Design, setting, participants, & measurements
Participants with predialysis CKD (defined as eGFR<60 ml/min per 1.73 m2) in the Safe Kidney Care Cohort Study were recruited for home usability testing of a novel medication inquiry system between January and September of 2013. Testing was through two mobile platforms: (1) short messaging service text or (2) personal digital assistant (e.g., iPod Touch). Twenty participants (one half assigned to one device and one half assigned to the other device) were enrolled and received an in-center tutorial on device usage before the end of the study visit. Participants were subsequently mailed three sample pill bottles with the name of randomly selected medications and asked to input these medications into the medication inquiry system. The medication inquiry system response options were as follows: (1) safe in CKD, (2) not safe in CKD, (3) use with caution/speak with your health care provider, or (4) error message (for an incorrectly inputted medication). Participants were asked to record the response issued by the medication inquiry system for each medication sent for usability testing. A user satisfaction survey was administered after completion of the protocol.Results
All participants owned a mobile telephone, but few owned a smartphone. Of 60 total medication queries, there were only three recorded errors, two of which occurred in the short messaging service texting group. Overall satisfaction with the application was high, with slightly higher satisfaction noted in the personal digital assistant group compared with the short messaging service group.Conclusions
The mobile health medication inquiry system application had general ease of use and high acceptance across two platforms among individuals representative of the CKD population. Tailored mobile health technology may improve medication safety in CKD. 相似文献Objective
Post-hepatectomy liver failure (PHLF) is the major cause of death following liver resection. The aim of this study was to evaluate the feasibility of an intraoperative simulation of post-resection liver function.Methods
Intraoperative liver function was measured by indocyanine green (ICG) clearance using the LiMON™ technology. In 20 patients undergoing anatomic liver resection, ICG plasma disappearance rate (PDR (%/min) and ICG retention at 15 min (R15) (%) were measured immediately after the induction of anaesthesia (t0), after selective arterial and portovenous inflow trial clamping (TC) of the resected liver segments (t1), after the completion of resection (t2) and before the closure of the abdominal cavity (t3).Results
The median baseline (t0) PDR was 16.5%/min. Trial clamping of the inflow (t1) resulted in a significant reduction in PDR to 10.5%/min. Results under TC were similar to those obtained after resection (t2) (median PDR: 10.5%/min). Linear regression modelling showed that post-resection liver volume could be accurately predicted by TC of liver inflow (P < 0.0001), but not by determining the resected liver volume. Simulated post-resection liver function under TC correlated well with PHLF and length of hospital stay.Conclusions
Intraoperative ICG clearance measurements allow real-time monitoring of intraoperative liver function during surgery. Trial clamping of arterial and portovenous inflow accurately predicts immediate post-resection liver function. The intraoperative measurement of liver function and simulation of post-resection liver function may help to avoid PHLF. 相似文献Methods: From the literature searches, 17 studies on everyday functioning and 40 studies on memory were obtained. Studies were only included if patients had an official diagnosis and were in the early stages of dementia.
Results: Complex instrumental activities of daily living were subject to greater impairment than basic activities of daily living. In particular, early dementia patients struggle with finance tasks; a deficit linked to impaired working memory. Regarding cognition, long-term memory is the earliest form of memory to decline as is well recognised. Evidence also indicates deficits in working and prospective memory, with inconsistent evidence about impairments of the former. A major limitation of the literature is a lack of studies assessing individual everyday activities and the associated error patterns that might occur.
Conclusion: This review critically assesses the status of translational research for everyday activities in early dementia, an area with critical implications for cognitive-based rehabilitation. Further research is required into the detailed assessment of individual everyday activity and specific memory deficits, in order to effectively map cognitive functions onto functional performance. 相似文献