全文获取类型
收费全文 | 37755篇 |
免费 | 2278篇 |
国内免费 | 133篇 |
专业分类
耳鼻咽喉 | 629篇 |
儿科学 | 940篇 |
妇产科学 | 966篇 |
基础医学 | 6265篇 |
口腔科学 | 666篇 |
临床医学 | 3513篇 |
内科学 | 6867篇 |
皮肤病学 | 979篇 |
神经病学 | 3864篇 |
特种医学 | 1981篇 |
外国民族医学 | 8篇 |
外科学 | 5268篇 |
综合类 | 281篇 |
一般理论 | 13篇 |
预防医学 | 2281篇 |
眼科学 | 1066篇 |
药学 | 2567篇 |
中国医学 | 76篇 |
肿瘤学 | 1936篇 |
出版年
2022年 | 261篇 |
2021年 | 491篇 |
2020年 | 335篇 |
2019年 | 492篇 |
2018年 | 633篇 |
2017年 | 503篇 |
2016年 | 723篇 |
2015年 | 730篇 |
2014年 | 877篇 |
2013年 | 1081篇 |
2012年 | 1892篇 |
2011年 | 1872篇 |
2010年 | 1093篇 |
2009年 | 1064篇 |
2008年 | 1576篇 |
2007年 | 1752篇 |
2006年 | 1808篇 |
2005年 | 1809篇 |
2004年 | 1673篇 |
2003年 | 1522篇 |
2002年 | 1551篇 |
2001年 | 1120篇 |
2000年 | 971篇 |
1999年 | 928篇 |
1998年 | 474篇 |
1997年 | 394篇 |
1996年 | 345篇 |
1995年 | 318篇 |
1994年 | 263篇 |
1993年 | 270篇 |
1992年 | 526篇 |
1991年 | 522篇 |
1990年 | 559篇 |
1989年 | 522篇 |
1988年 | 497篇 |
1987年 | 501篇 |
1986年 | 447篇 |
1985年 | 458篇 |
1984年 | 373篇 |
1983年 | 290篇 |
1979年 | 359篇 |
1978年 | 282篇 |
1977年 | 265篇 |
1976年 | 227篇 |
1975年 | 241篇 |
1974年 | 267篇 |
1973年 | 254篇 |
1972年 | 294篇 |
1971年 | 244篇 |
1969年 | 228篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Boffa Joseph W. Tock Jamie L. Morabito Danielle M. Schmidt Norman B. 《Cognitive therapy and research》2022,46(5):1016-1029
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study... 相似文献
2.
3.
M.F. Werner A. López-Rueda F.X. Zarco J. Blasco L. San Román S. Amaro E. Carrero R. Valero L. Oleaga J.M. Macho N. Bargalló 《Radiologia》2019,61(2):143-152
Purpose
Endovascular treatment with mechanical thrombectomy devices demonstrated high recanalization rates but functional outcome did not correlate with high rates of recanalization obtained. Patient selection prior to the endovascular treatment is very important in the final outcome of the patient. The primary aim of our study was to evaluate the prognostic value of posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) and Pons-Midbrain Index (PMI) scores in patients with Basilar Artery Occlusion (BAO) treated with successful angiographic recanalization after mechanical thrombectomy.Methods
Retrospective single-center study including 18 patients between 2008 and 2013 who had acute basilar artery occlusion managed with endovascular treatment within 24 hours from symptoms onset and with successful angiographic recanalization. The patients were initially classified into two groups according to clinical outcome and mortality at 90 days. For analysis we also divided patients into groups based on pc-ASPECTS (≥8vs.< 8) and PMI (≥3vs.< 3) on non-contrast CT (NCCT) and CT Angiography Source Images (CTASI). Imaging data were correlated to clinical outcome and mortality rate.Results
CTASI pc-ASPECTS, dichotomized at < 8 versus≥8, was associated with a favorable outcome (RR: 2.6; 95% CI: 1.3-5.2) and a reduced risk of death (RR: 6.5: 95% CI: 7.8-23.3). All patients that survived and were functionally independent had pc-ASPECTS score≥8. None of the 5 patients with CTASI pc-ASPECTS score less than 8 survived.Conclusion
PC-ASPECTS on CTASI is helpful for predicting functional outcome after BAO recanalization with endovascular treatment. These results should be validated in a randomized controlled trial in order to decide whether or not to treat a patient with BAO. 相似文献4.
Anders Elm Pedersen Esben Gjerløff Wedebye Schmidt Jesper Freddie Sørensen Carsten Faber Boye Schnack Nielsen Kim Holmstrøm Silje Haukali Omland Peter Tougaard Søren Skov Bo Bang 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(7):547-555
TL1A is a TNF‐like cytokine which has been shown to co‐stimulate TH1 and TH17 responses during chronic inflammation. The expression of this novel cytokine has been investigated in inflammatory disorders like rheumatoid arthritis and inflammatory bowel disease, but little is known about expression and induction in psoriasis. Indeed, the pathogenesis in psoriasis is still not fully understood and it is speculated that cytokines other than TNF‐α are important in subsets of patients. Also, for patients with severe disease that are treated with systemic anti‐TNF‐α blockade, novel candidates to be used as disease and response biomarkers are of high interest. Here, we demonstrate TL1A expression in biopsies from psoriatic lesions. Also, we investigated spontaneous and induced TL1A secretion from PBMCs and blood levels from a cohort of psoriasis patients. Here, increased spontaneous secretion from PBMCs was observed as compared to healthy controls and a small subset of patients had highly elevated TL1A in the blood. Interestingly, activation of PBMCs with various cytokines showed a decreased sensitivity for TL1A activation in psoriasis patients compared to healthy controls.TL1A levels in blood and biopsies could not be correlated with disease activity with this patient cohort. Thus, additional large‐scale studies are warranted to investigate TL1A as a biomarker. 相似文献
5.
Brian C. Werner 《Arthroscopy》2019,35(4):1072-1073
Achieving tendon-bone healing continues to be challenging after arthroscopic rotator cuff repair, particularly for larger tears, despite significant improvements in repair techniques and implants. Considerable effort has been invested in research to identify methods to improve healing, including patches and injectable biologics. Parathyroid hormone improves tendon-to-bone healing. Teriparatide is osteogenic, stimulating bone growth, and chondrogenic, promoting cartilage formation at the enthesis. However, it could be difficult to justify the expense and potential risk of systemic administration of a recombinant hormone to improve structural healing until improvement in clinical outcomes can be shown. 相似文献
6.
7.
Judith Brock Andreas Schmid Thomas Karrasch Petra Pfefferle Jutta Schlegel Inga Busse Annette Hauenschild Barbara Schmidt Maria Koukou Efthymia Arapogianni Andreas Schultz Miriam Thomalla Secil Akinci Johannes Kruse Winfried Padberg Andreas Schffler Jens Albrecht 《Clinical endocrinology》2019,91(3):400-410
8.
9.
Anna C. Rienmüller Sandro M. Krieg Franziska A. Schmidt Elias L. Meyer Bernhard Meyer 《The spine journal》2019,19(1):113-120
Background Context
The concept of dynamic stabilization (DS) of the lumbar spine for treatment of degenerative instability has been introduced almost two decades ago. Dynamic stabilization follows the principle of controlling movement in the coronal plane by providing load transfer of the spinal segment without fusion and, at the same time, reducing side effects such as adjacent segment disease (ASD). So far, only little is known about revision rates after DS due to ASD and screw loosening (SL).Purpose
The present study aimed to evaluate the longitudinal revision rates following dynamic pedicle screw stabilization in the lumbar spine and to determine specific risk factors predictive for ASD, SL, and overall reoperation in a large cohort with considerable follow-up.Design
We carried out a post hoc analysis of a prospectively collected database in a level I spine center.Patients Example
The patient sample comprised 283 (151 female/132 male) consecutive patients suffering from painful degenerative lumbar segmental instability with or without spinal stenosis who underwent DS of the lumbar spine (Ulrich Cosmic, Ulrich Medical, Ulm, Germany) between January 2008 and December 2011.Outcome Measures
Longitudinal reoperation rate and risk factors predictive for revision surgery were evaluated.Methods
We analyzed the longitudinal reoperation rate due to ASD and SL and overall reoperation. Risk factors such as age, gender, body mass index, lumbar lordosis (LL), number of segments, and number of previous surgeries were taken into account. Regular and mixed model logistic regressions were performed to determine risk factors for revision surgery on a patient and on a screw level.Results
The mean age was 65.7±10.2 years (range 31–88). One hundred thirty-two patients were stabilized in 1 segment, 134 in 2 segments, 15 in 3 segments, and 2 patients in 4 segments. Reoperation rate for ASD and SL after 1 year was 7.4 %, after 2 years was 15.0%, and after a mean follow-up of 51.4±15 months was 22.6%. Reasons for revision were SL in 19 cases (6.6%), ASD in 39 cases (13.7%), SL and ASD in 6 cases, hematoma in 2 cases (0.7%), cerebrospinal fluid fistulae in 3 cases (1.1%), infection in 6 cases (2.1%), and implant failure in 1 case (0.4%). The patients' age, the number of stabilized segments, and the number of previous surgeries and postoperative LL had a significant influence on the probability for revision surgery.Conclusions
Reoperation rates after DS of the lumbar spine are comparable with rigid fixations. The younger the patient and the more segments are involved, the lower the LL and the more previous surgeries were found, the higher was the risk of revision. Risk of revision was almost twice as high in men compared with women. We therefore conclude that for clear clinical indication and careful evaluation of preoperative imaging data, DS using the Cosmic system seems to be a possible option. The presented data will help to further tailor indication and patient selection. 相似文献10.
Cécile Vicier Lillian Werner Jonathan Chipman Lauren C. Harshman Dattatraya H. Patil Raina N. Fichorova Jennifer R. Rider Martin G. Sanda Lorelei A. Mucci Christopher J. Sweeney 《Clinical genitourinary cancer》2019,17(1):32-37