全文获取类型
收费全文 | 7541篇 |
免费 | 553篇 |
国内免费 | 42篇 |
专业分类
耳鼻咽喉 | 71篇 |
儿科学 | 138篇 |
妇产科学 | 201篇 |
基础医学 | 962篇 |
口腔科学 | 222篇 |
临床医学 | 792篇 |
内科学 | 1650篇 |
皮肤病学 | 148篇 |
神经病学 | 658篇 |
特种医学 | 675篇 |
外科学 | 1368篇 |
综合类 | 36篇 |
预防医学 | 254篇 |
眼科学 | 160篇 |
药学 | 321篇 |
中国医学 | 2篇 |
肿瘤学 | 478篇 |
出版年
2024年 | 12篇 |
2023年 | 106篇 |
2022年 | 196篇 |
2021年 | 335篇 |
2020年 | 200篇 |
2019年 | 294篇 |
2018年 | 321篇 |
2017年 | 238篇 |
2016年 | 263篇 |
2015年 | 318篇 |
2014年 | 416篇 |
2013年 | 417篇 |
2012年 | 628篇 |
2011年 | 621篇 |
2010年 | 369篇 |
2009年 | 364篇 |
2008年 | 433篇 |
2007年 | 423篇 |
2006年 | 334篇 |
2005年 | 300篇 |
2004年 | 242篇 |
2003年 | 240篇 |
2002年 | 168篇 |
2001年 | 91篇 |
2000年 | 65篇 |
1999年 | 78篇 |
1998年 | 30篇 |
1997年 | 36篇 |
1996年 | 23篇 |
1995年 | 12篇 |
1994年 | 11篇 |
1993年 | 13篇 |
1992年 | 28篇 |
1991年 | 28篇 |
1990年 | 19篇 |
1989年 | 19篇 |
1988年 | 26篇 |
1987年 | 26篇 |
1986年 | 27篇 |
1985年 | 24篇 |
1984年 | 16篇 |
1983年 | 14篇 |
1982年 | 11篇 |
1981年 | 16篇 |
1979年 | 29篇 |
1977年 | 10篇 |
1975年 | 12篇 |
1932年 | 13篇 |
1924年 | 12篇 |
1922年 | 8篇 |
排序方式: 共有8136条查询结果,搜索用时 0 毫秒
51.
According to our observation in ACL reconstruction, we find root tears of the posterior horn of the lateral meniscus as a
common concomitant injury in ACL-deficient knees. This might be a consequence of initial trauma or of the increased anterior–posterior
translation of the tibia and an overload impact on the posterior meniscus root in ACL-deficient knees. A tear of the posterior
horn of the medial meniscus causes a 25% increase in peak pressure in the medial compartment compared with that found in the
intact condition. The repair restores the peak contact pressure to normal (Allaire et al. in J Bone Joint Surg Am 90(9):1922–1931,
[2008]). A tear of the posterior horn of the lateral meniscus might have similar consequences. We hypothesize the surgical anatomical
reattachment of the root at the tibia helping to restore knee joint kinematics and helping to advance ACL-graft function.
This article presents an arthroscopical technique to reattach the posterior meniscus root in combination with ACL double-bundle
reconstruction. The procedure uses the tibial PL tunnel to fix the meniscus suture. 相似文献
52.
Chronic heart failure is a common disorder associated with unacceptably high mortality rates. Chronic renal disease and anemia are two important comorbidities that significantly influence morbidity and mortality in patients with chronic heart failure (CHF). Progress in CHF again may cause worsening of kidney function and anemia. To describe this vicious cycle, the term cardio-renal anemia syndrome has been suggested. Iron deficiency is part of the pathophysiology of anemia in both CHF and chronic kidney disease, which makes it an interesting target for treatment of anemia in cardio-renal anemia syndrome. Recently, studies have highlighted the potential clinical benefits of treating iron deficiency in patients with CHF, even if these patients are nonanemic. This article summarizes studies investigating the influence of iron deficiency with or without anemia in chronic kidney disease and CHF and gives an overview of preparations of intravenous iron currently available. 相似文献
53.
Wnuk M Hlushchuk R Janot M Tuffin G Martiny-Baron G Holzer P Imbach-Weese P Djonov V Huynh-Do U 《Kidney international》2012,81(12):1212-1225
Eph receptor tyrosine kinases and their ligands (ephrins) have a pivotal role in the homeostasis of many adult organs and are widely expressed in the kidney. Glomerular diseases beginning with mesangiolysis can recover, with podocytes having a critical role in this healing process. We studied here the role of Eph signaling in glomerular disease recovery following mesangiolytic Thy1.1 nephritis in rats. EphB4 and ephrinBs were expressed in healthy glomerular podocytes and were upregulated during Thy1.1 nephritis, with EphB4 strongly phosphorylated around day 9. Treatment with NPV-BHG712, an inhibitor of EphB4 phosphorylation, did not cause glomerular changes in control animals. Nephritic animals treated with vehicle did not have morphological evidence of podocyte injury or loss; however, application of this inhibitor to nephritic rats induced glomerular microaneurysms, podocyte damage, and loss. Prolonged NPV-BHG712 treatment resulted in increased albuminuria and dysregulated mesangial recovery. Additionally, NPV-BHG712 inhibited capillary repair by intussusceptive angiogenesis (an alternative to sprouting angiogenesis), indicating a previously unrecognized role of podocytes in regulating intussusceptive vessel splitting. Thus, our results identify EphB4 signaling as a pathway allowing podocytes to survive transient capillary collapse during glomerular disease. 相似文献
54.
Philipp Neumann Hans-Joachim Bungartz Miriam Mehl Tobias Neckel & Tobias Weinzierl 《Communications In Computational Physics》2012,12(1):65-84
We couple different flow models, i.e. a finite element solver for the Navier-Stokes equations and a Lattice Boltzmann automaton, using the framework Peano as a
common base. The new coupling strategy between the meso- and macroscopic solver
is presented and validated in a 2D channel flow scenario. The results are in good
agreement with theory and results obtained in similar works by Latt et al. In addition,
the test scenarios show an improved stability of the coupled method compared to pure
Lattice Boltzmann simulations. 相似文献
55.
56.
Cyrus Behzadi Murat Karul Frank Oliver Henes Azien Laqmani Philipp Catala-Lehnen Wolfgang Lehmann Hans-Dieter Nagel Gerhard Adam Marc Regier 《World journal of radiology》2015,7(1):22-27
AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patients were enrolled in our study who had suffered from a wrist trauma and showed typical clinical symptoms suspicious of an acute scaphoid fracture. All patients had initially undergone conventional radiography. Subsequent MDCT was performed within 10 d because of persisting clinical symptoms. Using the MDCT data as the reference standard, a fourfold table was used to classify the test results. The effective dose and impaired energy were assessed in order to compare the radiation burden of the two techniques. The Wilcoxon test was performed to compare the two diagnostic modalities.RESULTS: Conventional radiography showed 34 acute fractures of the scaphoid in 124 patients(42.2%). Subsequent MDCT revealed a total of 42 scaphoid fractures. The sensitivity of conventional radiography for scaphoid fracture detection was 42.8% and its specificity was 80% resulting in an overall accuracy of 59.6%. Conventional radiography was significantly inferior to MDCT(P < 0.01) concerning scaphoidfracture detection. The mean effective dose of MDCT was 0.1 m Sv compared to 0.002 m Sv of conventional radiography.CONCLUSION: Conventional radiography is insufficient for accurate scaphoid fracture detection. Regarding the almost negligible effective dose, MDCT should serve as the first imaging modality in wrist trauma. 相似文献
57.
Streibert Fridolin Bernhardt Claudia Simon Philipp Hilbert-Carius Peter Wrigge Hermann 《Der Anaesthesist》2023,72(1):57-62
Die Anaesthesiologie - Die Anlage einer Magensonde im OP oder auf einer Intensivstation (ITS) stellt eine alltäglich durchgeführte Prozedur dar. Obwohl die Sonde häufig durch... 相似文献
58.
Swen Hesse Franziska Moeller David Petroff Donald Lobsien Julia Luthardt Ralf Regenthal Georg-Alexander Becker Marianne Patt Eva Thomae Anita Seese Philipp M. Meyer Florian Then Bergh Osama Sabri 《European journal of nuclear medicine and molecular imaging》2014,41(5):827-835
Purpose
Modulation of the immune system by the CNS may involve serotonergic regulation via the brain serotonin transporters (SERT). This regulation may be disturbed in patients with CNS disorders including multiple sclerosis (MS). Central serotonergic mechanisms have not been investigated in MS by in vivo imaging. The objective of the study was to assess the availability of SERT in antidepressant-naive patients with MS by means of PET.Methods
Included in this study were 23 patients with MS and 22 matched healthy volunteers who were investigated with PET and the SERT-selective marker [11C]DASB, and distribution volume ratios were determined. Clinical assessment of the patients included the expanded disability status scale, the MS fatigue scale Würzburger Erschöpfungsinventar bei MS (WEIMuS) and the Beck Depression Inventory (BDI). The PET data were analysed with both volume-of-interest and voxel-based analyses to determine regional SERT availability.Results
Patients had lower SERT availability in the cingulate cortex, the thalamus and the insula, and increased availability in the orbitofrontal cortex. Patients with relapsing/remitting MS tended to have lower SERT in the hippocampus, whereas patients with primary progressive disease showed increased SERT availability in prefrontal regions. There was a positive correlation between SERT availability in the insula and both depression and fatigue scores (r?=?0.56 vs. BDI, p?=?0.02; r?=?0.49 vs. WEIMuS, p?=?0.05).Conclusion
Serotonergic neurotransmission in MS patients is altered in limbic and paralimbic regions as well as in the frontal cortex that this appears to contribute to psychiatric symptoms of MS. 相似文献59.
Effectivity of a T-cell-adapted induction therapy with anti-thymocyte globulin (Sangstat). 总被引:1,自引:0,他引:1
Achim Koch Volker Daniel Thomas J Dengler Philipp Albert Schnabel Siegfried Hagl Falk-Udo Sack 《The Journal of heart and lung transplantation》2005,24(6):708-713
BACKGROUND: Cytolytic induction therapy with anti-thymocyte globulin (ATG) should induce effective immunosuppression, with a low rate of rejection in the initial phase after heart transplantation. Induction therapy with ATG allows post-operative renal recovery without the negative effects of highly nephrotoxic cyclosporine levels. An increased rate of infection is a common problem, however, and has been associated with "over-immunosuppression" early after transplantation. Therefore, we investigated whether reduced T-cell-adapted ATG induction therapy could be performed without increasing the risk of graft loss by rejection and whether reductions in infection rates and costs are possible. METHODS: Between March 1999 and December 2002, T-cell-adapted ATG induction therapy with ATG (Sangstat) (1.5 mg/kg) was given to 62 heart transplant recipients (study group) starting on post-operative Days 1 to 6. T-lymphocyte sub-populations were screened daily using flow cytometry. If total lymphocytes were <100/microl (reference 1,300 to 2,300/microl), T-helper lymphocytes (CD4+) <50/microl (reference >500/microl) and T-suppressor cells (CD8+) <50/microl (reference >300/microl), then no ATG was given. Further immunosuppression was continued with triple therapy consisting of methylprednisolone, azathioprine and cyclosporine. An historic group of heart transplant recipients given a full-dose ATG regimen for 8 days served as controls. These recipients were treated with ATG (Merieux 1.5 mg/kg) until reaching monoclonal cyclosporine levels of >300 mg/dl. Additional immunosuppressive treatment did not differ. Patients in both groups received systemic antibiotics (Imipenem) peri-operatively. Results of routine endomyocardial biopsies and rates of infections were examined. RESULTS: Study group patients were older (52 +/- 10 vs 49 +/- 14 years). In the study group, mean cumulative ATG dose was reduced significantly to 596 +/- 220 mg (p < 0.05) for 3.9 +/- 1.6 days compared with 1,159 +/- 376 mg for 6.9 +/- 1.1 days in the control group. The rate of cytomegalovirus (CMV) seroconversion was 23% in the study group compared with 13% in the control group. Rate of deep sternal infections was lower in the study group (1.6% vs 3.2%). The mean rejection rate in the first 3 months was 0.4 +/- 0.7 for the study patients (185 biopsies) vs 1.1 +/- 1.7 for controls (237 biopsies). All biopsies with ISHLT Grade >2 were treated successfully with 1,000 mg of methylprednisolone intravenously for 3 days. Both groups showed a similar 1-year survival rate (study 88%, control 89%). CONCLUSIONS: T-cell-adapted ATG induction therapy can be a helpful tool for individualized immunosuppression. It is not associated with an increased rate of rejection. Lower doses of immunosuppression help to minimize the rates of infection. In addition, cytolytic induction therapy combined with reduced ATG results in significant cost reduction. 相似文献
60.