全文获取类型
收费全文 | 3569篇 |
免费 | 300篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 45篇 |
儿科学 | 119篇 |
妇产科学 | 54篇 |
基础医学 | 565篇 |
口腔科学 | 41篇 |
临床医学 | 439篇 |
内科学 | 676篇 |
皮肤病学 | 66篇 |
神经病学 | 308篇 |
特种医学 | 74篇 |
外科学 | 487篇 |
综合类 | 26篇 |
一般理论 | 2篇 |
预防医学 | 439篇 |
眼科学 | 103篇 |
药学 | 209篇 |
中国医学 | 7篇 |
肿瘤学 | 216篇 |
出版年
2023年 | 41篇 |
2022年 | 57篇 |
2021年 | 153篇 |
2020年 | 100篇 |
2019年 | 149篇 |
2018年 | 147篇 |
2017年 | 106篇 |
2016年 | 102篇 |
2015年 | 116篇 |
2014年 | 177篇 |
2013年 | 221篇 |
2012年 | 322篇 |
2011年 | 302篇 |
2010年 | 150篇 |
2009年 | 118篇 |
2008年 | 182篇 |
2007年 | 194篇 |
2006年 | 164篇 |
2005年 | 139篇 |
2004年 | 129篇 |
2003年 | 119篇 |
2002年 | 115篇 |
2001年 | 50篇 |
2000年 | 65篇 |
1999年 | 36篇 |
1998年 | 31篇 |
1997年 | 23篇 |
1996年 | 14篇 |
1995年 | 17篇 |
1994年 | 12篇 |
1993年 | 11篇 |
1992年 | 32篇 |
1991年 | 17篇 |
1990年 | 11篇 |
1989年 | 21篇 |
1988年 | 26篇 |
1987年 | 18篇 |
1986年 | 14篇 |
1985年 | 26篇 |
1984年 | 13篇 |
1983年 | 14篇 |
1982年 | 10篇 |
1981年 | 11篇 |
1979年 | 15篇 |
1977年 | 6篇 |
1976年 | 8篇 |
1974年 | 11篇 |
1973年 | 7篇 |
1969年 | 6篇 |
1966年 | 6篇 |
排序方式: 共有3876条查询结果,搜索用时 15 毫秒
81.
McKenzie S. White William Z. Horton Julie P. Burland Matthew K. Seeley Lindsey K. Lepley 《Journal of Athletic Training》2021,56(3):272
ContextResearchers have traditionally used motion capture to quantify discrete data points (peak values) during hop testing. However, these analyses restrict the evaluation to a single time point (ie, certain percentage of stance) and provide only a narrow view of movement. Applying more comprehensive analyses may help investigators identify important characteristics that are masked by discrete analyses often used to screen patients for activity.ObjectiveTo examine the utility of functional data analyses to reveal asymmetries that are undetectable using discrete (ie, single time point) evaluations in participants with a history of anterior cruciate ligament reconstruction (ACLR) who achieved clinical hop symmetry.DesignCross-sectional study.SettingLaboratory.Patients or Other ParticipantsFifteen participants with unilateral ACLR (age = 21 ± 3 years, time from surgery = 4 ± 3 years) and 15 control participants without ACLR (age = 23 ± 2 years).Intervention(s)Lower extremity biomechanics during the triple–hop-for-distance task for the ACLR and contralateral limbs of patients and a representative limb of control participants were measured.Main Outcome Measure(s)Peak sagittal-plane joint power, joint work, and power profiles were determined.ResultsUsing discrete analyses, we identified lower peak knee power and work in the ACLR limb compared with the contralateral and control limbs (P < .05) but were unable to demonstrate differences at the ankle or hip. Using functional data analyses, we observed asymmetries at the ankle, knee, and hip between the ACLR and contralateral or control limbs throughout stance (P < .05), and it was revealed that these asymmetries stemmed from knee power deficits that were prominent during early loading.ConclusionsDespite achieving hop-distance symmetry, the ACLR knees absorbed less power. Although this information was revealed using discrete analyses, underlying asymmetries at the ankle and hip were masked. Using functional data analyses, we found interlimb asymmetries at the ankle, knee, and hip. Importantly, we found that functional data analyses more fully elucidated the extent and source of asymmetries, which can be used by clinicians and researchers alike to aid in clinical decision making. 相似文献
82.
83.
84.
J. Troy Blackburn Marc F. Norcross Lindsey N. Cannon Steven M. Zinder 《Journal of Athletic Training》2013,48(6):764-772
Context:
Greater hamstrings stiffness is associated with less anterior tibial translation during controlled perturbations. However, it is unclear how hamstrings stiffness influences anterior cruciate ligament (ACL) loading mechanisms during dynamic tasks.Objective:
To evaluate the influence of hamstrings stiffness on landing biomechanics related to ACL injury.Design:
Cross-sectional study.Setting:
Research laboratory.Patients or Other Participants:
A total of 36 healthy, physically active volunteers (18 men, 18 women; age = 23 ± 3 years, height = 1.8 ± 0.1 m, mass = 73.1 ± 16.6 kg).Intervention(s):
Hamstrings stiffness was quantified via the damped oscillatory technique. Three-dimensional lower extremity kinematics and kinetics were captured during a double-legged jump-landing task via a 3-dimensional motion-capture system interfaced with a force plate. Landing biomechanics were compared between groups displaying high and low hamstrings stiffness via independent-samples t tests.Main Outcome Measure(s):
Hamstrings stiffness was normalized to body mass (N/m·kg−1). Peak knee-flexion and -valgus angles, vertical and posterior ground reaction forces, anterior tibial shear force, internal knee-extension and -varus moments, and knee-flexion angles at the instants of each peak kinetic variable were identified during the landing task. Forces were normalized to body weight, whereas moments were normalized to the product of weight and height.Results:
Internal knee-varus moment was 3.6 times smaller in the high-stiffness group (t22 = 2.221, P = .02). A trend in the data also indicated that peak anterior tibial shear force was 1.1 times smaller in the high-stiffness group (t22 = 1.537, P = .07). The high-stiffness group also demonstrated greater knee flexion at the instants of peak anterior tibial shear force and internal knee-extension and -varus moments (t22 range = 1.729–2.224, P < .05).Conclusions:
Greater hamstrings stiffness was associated with landing biomechanics consistent with less ACL loading and injury risk. Musculotendinous stiffness is a modifiable characteristic; thus exercises that enhance hamstrings stiffness may be important additions to ACL injury-prevention programs.Key Words: viscoelastic, musculotendinous, valgus, anterior tibial shear forceKey Points
- Individuals with greater hamstrings stiffness displayed more favorable landing biomechanics for anterior cruciate ligament (ACL) loading and injury risk than individuals with less hamstrings stiffness as evidenced by smaller frontal-plane knee moments and a more-flexed knee at the instants of critical biomechanical knee events.
- Greater hamstrings stiffness was associated with smaller anterior tibial shear forces.
- A high level of hamstrings stiffness may limit ACL injury risk by limiting frontal- and sagittal-plane ACL-loading mechanisms.
85.
Helen Venn Barbara Montagne Lindsey Murray Michael Burt Elisa Frigerio 《Cognitive neuropsychiatry》2013,18(6):505-520
Introduction?A number of studies have reported mood‐congruent biases in processing facial expressions of emotion in depression and mania. Most of them have failed to establish that mood reliably affects relevant more than irrelevant expressions, or that the effect is specifically mood‐related rather than due to resource or task difficulty artefacts. The aim was to examine, using appropriate statistical methods, whether depressed mood in bipolar patients decreases and manic mood increases sensitivity to facial expressions of happiness and vice versa for facial expressions of negative emotion. Methods?Sensitivity to facial expression of six basic emotions in bipolar patients when depressed and when manic was compared to closely matched controls. Results?Mood‐related biases in sensitivity to facial expressions of happiness and of negative affect in general operate in persons with bipolar disorder when depressed. There is little evidence of similar biases in persons with bipolar disorder when manic. Conclusions?These data show a mood‐congruent bias in sensitivity to facial expressions in bipolar depressed patients. 相似文献
86.
Dual echo vessel‐encoded ASL for simultaneous BOLD and CBF reactivity assessment in patients with ischemic cerebrovascular disease
下载免费PDF全文
![点击此处可从《Magnetic resonance in medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
87.
R. Paul Robertson Lindsey D. Bogachus Elizabeth Oseid Susan Parazzoli Mary Elizabeth Patti Michael R. Rickels Christian Schuetz Ty Dunn Timothy Pruett A.N. Balamurugan David E.R. Sutherland Gregory Beilman Melena D. Bellin 《Diabetes》2015,64(2):565-572
We used intravenous arginine with measurements of insulin, C-peptide, and glucagon to examine β-cell and α-cell survival and function in a group of 10 chronic pancreatitis recipients 1–8 years after total pancreatectomy and autoislet transplantation. Insulin and C-peptide responses correlated robustly with the number of islets transplanted (correlation coefficients range 0.81–0.91; P < 0.01–0.001). Since a wide range of islets were transplanted, we normalized the insulin and C-peptide responses to the number of islets transplanted in each recipient for comparison with responses in normal subjects. No significant differences were observed in terms of magnitude and timing of hormone release in the two groups. Three recipients had a portion of the autoislets placed within their peritoneal cavities, which appeared to be functioning normally up to 7 years posttransplant. Glucagon responses to arginine were normally timed and normally suppressed by intravenous glucose infusion. These findings indicate that arginine stimulation testing may be a means of assessing the numbers of native islets available in autologous islet transplant candidates and is a means of following posttransplant α- and β-cell function and survival. 相似文献
88.
Self‐Reported Outcomes in Individuals Aged 65 and Older Admitted for Treatment to an Acute Care Surgical Service: A 6‐Month Prospective Cohort Study
下载免费PDF全文
![点击此处可从《Journal of the American Geriatrics Society》网站下载免费的PDF全文](/ch/ext_images/free.gif)
89.
90.