全文获取类型
| 收费全文 | 21763篇 |
| 免费 | 2185篇 |
| 国内免费 | 32篇 |
专业分类
| 耳鼻咽喉 | 142篇 |
| 儿科学 | 741篇 |
| 妇产科学 | 788篇 |
| 基础医学 | 3183篇 |
| 口腔科学 | 563篇 |
| 临床医学 | 2604篇 |
| 内科学 | 4197篇 |
| 皮肤病学 | 328篇 |
| 神经病学 | 2051篇 |
| 特种医学 | 552篇 |
| 外科学 | 2666篇 |
| 综合类 | 516篇 |
| 一般理论 | 18篇 |
| 预防医学 | 2370篇 |
| 眼科学 | 255篇 |
| 药学 | 1825篇 |
| 中国医学 | 34篇 |
| 肿瘤学 | 1147篇 |
出版年
| 2021年 | 249篇 |
| 2020年 | 174篇 |
| 2019年 | 289篇 |
| 2018年 | 329篇 |
| 2017年 | 237篇 |
| 2016年 | 289篇 |
| 2015年 | 331篇 |
| 2014年 | 455篇 |
| 2013年 | 690篇 |
| 2012年 | 1049篇 |
| 2011年 | 1070篇 |
| 2010年 | 609篇 |
| 2009年 | 562篇 |
| 2008年 | 934篇 |
| 2007年 | 1123篇 |
| 2006年 | 1029篇 |
| 2005年 | 934篇 |
| 2004年 | 986篇 |
| 2003年 | 899篇 |
| 2002年 | 892篇 |
| 2001年 | 713篇 |
| 2000年 | 701篇 |
| 1999年 | 650篇 |
| 1998年 | 263篇 |
| 1997年 | 255篇 |
| 1996年 | 219篇 |
| 1995年 | 227篇 |
| 1994年 | 177篇 |
| 1993年 | 185篇 |
| 1992年 | 524篇 |
| 1991年 | 500篇 |
| 1990年 | 449篇 |
| 1989年 | 534篇 |
| 1988年 | 432篇 |
| 1987年 | 397篇 |
| 1986年 | 442篇 |
| 1985年 | 357篇 |
| 1984年 | 307篇 |
| 1983年 | 321篇 |
| 1982年 | 181篇 |
| 1981年 | 167篇 |
| 1979年 | 247篇 |
| 1978年 | 185篇 |
| 1977年 | 161篇 |
| 1976年 | 160篇 |
| 1974年 | 156篇 |
| 1973年 | 184篇 |
| 1972年 | 152篇 |
| 1971年 | 160篇 |
| 1970年 | 140篇 |
排序方式： 共有10000条查询结果，搜索用时 15 毫秒
1.
2.
3.
Andrea Stracciolini Jennifer Luz Gregory Walker Nicholas M. Edwards Avery D. Faigenbaum Gregory D. Myer 《The Physician and sportsmedicine》2020,48(2):199-207
ABSTRACT
Objective
To investigate primary care physician clinical practice patterns, barriers, and education surrounding pediatric physical activity (PA), and to compare practice patterns by discipline. 相似文献4.
Emma J. Walker Noni E. MacDonald Nehal Islam Nicole Le Saux Karina A. Top Deshayne B. Fell 《Vaccine》2019,37(13):1725-1735
Objective
To systematically review literature on uptake and timeliness of diphtheria-tetanus-pertussis, measles-mumps-rubella, and/or polio-containing vaccines in infants who were born preterm, with a low birth weight, and/or with chronic health conditions that were diagnosed within the first 6?months of life.Methods
Using a standardized search strategy developed by a medical librarian, records were extracted from MEDLINE, Embase, Database of Abstracts of Reviews of Effects, and CINAHL up to May 8, 2018.Results
Out of the 1997 records that were screened, we identified 21 studies that met inclusion criteria. Eleven studies assessed vaccine coverage and/or timeliness in preterm infants, 6 in low birth weight infants, and 7 in children with chronic health conditions. Estimates of coverage in these populations were highly variable, ranging from 40% to 100% across the vaccines and population groups.Conclusions
There is a lack of studies reporting coverage and timeliness of routine immunizations in special populations of children.Policy implications
Our review suggests a need for improved surveillance of immunization status in special populations of infants, as well as a need for standardization of reporting practices. 相似文献5.
Denise Lee Marcella D. Walker Hsin Yi Chen John A. Chabot James A. Lee Jennifer H. Kuo 《Surgery》2019,165(1):107-113
Background
Bone mineral density (BMD) has been found to improve after parathyroidectomy (PTX) in patients with primary hyperparathyroidism. There are few data on the effect of PTX on BMD in normocalcemic and normohormonal primary hyperparathyroidism.Methods
A retrospective analysis of 92 primary hyperparathyroidism patients who underwent PTX between 2004 and 2012 with pre- and post-PTX dual-energy x-ray absorptiometry was performed. Within-person changes in BMD pre- and post-PTX were analyzed using log linear mixed models, stratified by biochemical status.Results
Bone mineral density increased post-PTX in the whole cohort at the lumbar spine (+2.5%), femoral neck (+2.1%), and total hip (+1.9%) and decreased at the one-third radius (–0.9%). On comparison of BMD changes by profile, BMD increased in those with the typical profile at the lumbar spine (3.2%), femoral neck (2.9%), and total hip (2.9%) but declined at the one-third radius (–1.5%). In contrast, BMD improved only at the femoral neck (4.3%) in the normohormonal group and did not change at any site in the normocalcemic group. The typical group had a greater increase in BMD over time at the femoral neck and total hip compared with normocalcemic patients.Conclusion
Our results indicate that the skeletal benefit of PTX was attenuated in normocalcemic and normohormonal patients, suggesting that skeletal changes after PTX may depend on biochemical profile. 相似文献6.
7.
Alexander S. Dakos Ellen M. Walker Huai Jiang Barry E. Stein Benjamin A. Rowland 《The European journal of neuroscience》2019,50(11):3702-3712
Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can be reinstated by a non‐invasive multisensory training procedure in which spatiotemporally concordant visual‐auditory pairs are repeatedly presented within the blind hemifield. Despite this recovery of visual responsiveness, the loss of visual cortex was expected to result in permanent deficits in that hemifield, especially when visual events in both hemifields compete for attention and access to the brain's visuomotor circuitry. This was evaluated in the present study in a visual choice paradigm in which the two visual hemifields of recovered cats were simultaneously stimulated with equally valent visual targets. Surprisingly, the expected disparity was not found, and some animals even preferred stimuli presented in the previously blind hemifield. This preference persisted across multiple stimulus intensity levels and there was no indication that animals were less aware of cues in the previously blind hemifield than in its spared counterpart. Furthermore, when auditory cues were combined with visual cues, the enhanced performance they produced on a visual task was no greater in the normal than in the previously blind hemifield. These observations suggest that the multisensory rehabilitation paradigm revealed greater inherent visual information processing potential in the previously blind hemifield than was believed possible given the loss of visual cortex. 相似文献
8.
Molly Orcutt Wendy C. King Melissa A. Kalarchian Michael J. Devlin Marsha D. Marcus Luis Garcia Kristine J. Steffen James E. Mitchell 《Surgery for obesity and related diseases》2019,15(2):295-303
Background
A history of childhood maltreatment and psychopathology are common in adults with obesity.Objectives
To report childhood maltreatment and to evaluate associations between severity and type of childhood maltreatment and lifetime history of psychopathology among adults with severe obesity awaiting bariatric surgery.Setting
Four clinical centers of the Longitudinal Assessment of Bariatric Surgery Research Consortium.Methods
The Childhood Trauma Questionnaire, which assesses presence/severity (i.e., none, mild, moderate, severe) of physical abuse, mental abuse, physical neglect, mental neglect, and sexual abuse, was completed by 302 female and 66 male bariatric surgery patients. Presurgery lifetime history of psychopathology and suicidal ideation/behavior were assessed with the Structured Clinical Interview for DSM-IV and the Suicidal Behavioral Questionnaire-Revised, respectively. Presurgery lifetime history of antidepressant use was self-reported.Results
Two thirds (66.6%) of females and 47.0% of males reported at least 1 form of childhood trauma; 42.4% and 24.2%, respectively, at greater than or equal to moderate severity. Among women, presence/greater severity of childhood mental or physical abuse or neglect was associated with a higher risk of history of psychopathology (i.e., major depressive disorder, posttraumatic stress disorder, other anxiety disorder, alcohol use disorder, binge eating disorder), suicidal ideation/behavior and antidepressant use (P for all ≤ .02). These associations were independent of age, race, education, body mass index, and childhood sexual abuse. Childhood sexual abuse was independently associated with a history of suicidal ideation/behavior and antidepressant use only (P for both ≤ .05). Statistical power was limited to evaluate these associations among men.Conclusion
Among women with obesity, presence/severity of childhood trauma was positively associated with relatively common psychiatric disorders. 相似文献9.
