全文获取类型
收费全文 | 2146篇 |
免费 | 146篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 27篇 |
妇产科学 | 72篇 |
基础医学 | 254篇 |
口腔科学 | 26篇 |
临床医学 | 256篇 |
内科学 | 588篇 |
皮肤病学 | 26篇 |
神经病学 | 291篇 |
特种医学 | 67篇 |
外科学 | 324篇 |
综合类 | 7篇 |
预防医学 | 61篇 |
眼科学 | 15篇 |
药学 | 97篇 |
中国医学 | 4篇 |
肿瘤学 | 177篇 |
出版年
2023年 | 19篇 |
2022年 | 15篇 |
2021年 | 51篇 |
2020年 | 33篇 |
2019年 | 55篇 |
2018年 | 53篇 |
2017年 | 54篇 |
2016年 | 53篇 |
2015年 | 48篇 |
2014年 | 86篇 |
2013年 | 101篇 |
2012年 | 145篇 |
2011年 | 145篇 |
2010年 | 92篇 |
2009年 | 88篇 |
2008年 | 157篇 |
2007年 | 135篇 |
2006年 | 107篇 |
2005年 | 119篇 |
2004年 | 108篇 |
2003年 | 106篇 |
2002年 | 103篇 |
2001年 | 47篇 |
2000年 | 55篇 |
1999年 | 38篇 |
1998年 | 21篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 15篇 |
1994年 | 10篇 |
1993年 | 10篇 |
1992年 | 22篇 |
1991年 | 20篇 |
1990年 | 15篇 |
1989年 | 9篇 |
1988年 | 18篇 |
1987年 | 8篇 |
1986年 | 7篇 |
1985年 | 6篇 |
1984年 | 9篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 5篇 |
1975年 | 4篇 |
1974年 | 5篇 |
1973年 | 7篇 |
1969年 | 8篇 |
1968年 | 8篇 |
排序方式: 共有2302条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Izabela Zaborniak Pawe Chmielarz Karol Wolski Gabriela Grzes Abdirisak A. Isse Armando Gennaro Szczepan Zapotoczny Andrzej Sobkowiak 《Macromolecular chemistry and physics.》2019,220(13)
Inspired by tea stains, a plant polyphenolic‐based macroinitiator is prepared for the first time by partial modification of tannic acid (TA) with 2‐bromoisobutyryl bromide. In accordance with the “grafting from” methodology, a naturally occurring star‐like polymer with a polar gallotannin core and a hydrophobic poly(n‐butyl acrylate) side arms is synthesized via a simplified electrochemically mediated ATRP (seATRP), utilizing multiple‐step potential electrolysis. To investigate the kinetics of the electrochemical catalytic process triggered by reduction of Cu(II) or Fe(III) catalytic complex in the presence of the multifunctional initiator, cyclic voltammetry measurements are conducted. The naturally derived tannin macromolecule shows narrow MWDs (? = 1.57). Moreover, solvolysis of the star polymer to cleave the side arms and characterize them indicates that all chains grow to the same length (homopolymers with Mw/Mn <1.17), which confirms the well‐controlled seATRP. The structure of the obtained TA‐based systems is characterized microscopically (AFM) and spectroscopically (1H NMR, FT‐IR). Atomic force microscopy measurements precisely determine the diameters of the obtained star polymers (19.7 ± 3.3 nm). These new star polymers may find biomedical applications as drug delivery systems and antifouling or antimicrobial coatings. 相似文献
6.
Fabrizio Di Francesco Gennaro De Marco Ugo Antonello Gironi Carnevale Michele Lanza Alessandro Lanza 《Journal of prosthodontic research》2019,63(1):15-24
Purpose
The number of implants needed to support a maxillary overdenture is still a controversial issue. The aim of this systematic review was to investigate the number of implants required to support a maxillary overdenture in order to obtain optimal treatment outcomes in terms of implant survival, overdenture longevity and patient satisfaction.Study selection
Pubmed and EMBASE databes were systematically searched and complemented by hand searching from 2000 to 2017. The Prisma statement and a PICOS approach were adopted. All selected articles provided at least two-year follow-up and 10 totally edentulous patients. Survival rate of implants and overdentures were statistically analyzed according to number of implants and according to splitting technique, employing non-parametric Fisher Test for unpaired data. For the pooled analysis of implant failures, the odds ratio between group of 4 splinted implants and group of more than 4 splinted was calculated.Results
A total of 28 articles were included. Data analysis of the included studies showed that the survival rate of implants appeared higher in ≥ 4 implants group, whereas the high survival rate of overdentures and patient satisfaction were not significantly influenced by the number of implants.Conclusions
The findings of our analysis indicate that overall the most frequent tendency is to place at least four implants, splinted or unsplinted, in order to ensure a higher survival rate of implants. However, the relationship between overdenture survival, the patient’s quality of life, and the number of implants required to support a maxillary overdenture has yet to be clarified. 相似文献7.
8.
The effects of femoral component design on the patello-femoral joint in a PS total knee arthroplasty
Pier Francesco Indelli Massimiliano Marcucci Gennaro Pipino Sophie Charlton Christian Carulli Massimo Innocenti 《Archives of orthopaedic and trauma surgery》2014,134(1):59-64
Introduction
Anterior knee pain following TKA performed utilizing the PFC Sigma system still represents a cause of failure. The purpose of this study was to evaluate whether or not a recent change in the femoral design (PFC Sigma PS) had a positive impact on the patello-femoral complication rate.Materials and methods
A consecutive series of 100 TKA using the PFC Sigma PS system was followed prospectively for a minimum of 3 years. All patellae were replaced and a standard lateral release was never performed. Radiographic analysis following the Knee Society Score (KSS) included antero-posterior weight-bearing, lateral and bilateral axial radiographs. TKA rotational alignment was recorded at the final follow-up in 30 consecutive knees by performing a CT evaluation.Results
Good to excellent clinical results according to the KSS were achieved in 94 % of the knees. Survival without need of reoperation for any reason was 98 % at 3 years minimum follow-up; two reoperations were done for removal of fibromatous intra-articular tissue (“Clunk syndrome”). There were no revisions for septic or aseptic loosening of the components. The mean ROM improved from 104° preoperatively to 115° (97°–132°) postoperatively: postoperative flexion was 120° or more in 58 % of the knees. Severe anterior knee pain was present in 9 % of patients. Radiographic evaluation showed 90 knees with a tibio-femoral anatomical axis between 8° and 2° of valgus (±3° from the intraoperative goal). CT evaluation of 30 consecutive knees showed that the femoral component positioning in relationship to the trans-epicondylar axis had only 2.80° of external rotation (±2.10°) with respect to a planned external rotation of 3°. This difference was statistically significant.Conclusions
Although the PFC Sigma PS system provides good and predictable results for tricompartmental arthritis of the knee, anterior mechanism complications still represent a reason for dissatisfaction in a substantial group of patients. 相似文献9.
Giangennaro Coppola Alessandra D’Amico Erica Pironti Federica Martino Elena Santoro Nilde Di Paolo Claudia Isone Gennaro Catone 《Brain & development》2014
We report the case of a 11-year-old girl who developed an isolated hand-writing disorder with dysgraphia at the beginning of the school year in the sixth grade. A brain magnetic resonance angiography showed a round arteriovenous malformation sited in the left side of the midbrain extending to the ipsilateral medio-basal thalamus. Child neurologists should never neglect a thorough neurological evaluation in case of isolated worsening of handwriting, to rule out possible underlying organic causes. 相似文献
10.
Matteo Beretta Piccoli MSc Alberto Rainoldi PhD Carolin Heitz PT MSc Marianne Wüthrich PT MSc Gennaro Boccia PhD Enrico Tomasoni MSc Carlo Spirolazzi PT Michele Egloff MA Marco Barbero PT 《Muscle & nerve》2014,49(3):413-421
Introduction: We describe the innervation zone (IZ) location in 43 muscles to provide information for appropriate positioning of bipolar electrodes for clinical and research applications. Methods: The IZ was studied in 40 subjects (20 men and 20 women) using multichannel surface electromyography (sEMG). Signal quality was checked visually to identify motor unit action potentials and estimate muscle fiber conduction velocity. Results: Results in 33 muscles were classified as excellent or good, because it was possible to identify an area which is favorable for appropriate positioning of an electrode pair without the need to previously determine the IZ location. Conclusions: Knowledge of IZ location will increase standardization and repeatability of sEMG measures. Muscle Nerve 49 :413–421, 2014 相似文献