全文获取类型
收费全文 | 11416篇 |
免费 | 626篇 |
国内免费 | 92篇 |
专业分类
耳鼻咽喉 | 98篇 |
儿科学 | 351篇 |
妇产科学 | 178篇 |
基础医学 | 1296篇 |
口腔科学 | 485篇 |
临床医学 | 964篇 |
内科学 | 2815篇 |
皮肤病学 | 244篇 |
神经病学 | 1000篇 |
特种医学 | 479篇 |
外科学 | 1794篇 |
综合类 | 20篇 |
一般理论 | 2篇 |
预防医学 | 641篇 |
眼科学 | 103篇 |
药学 | 590篇 |
中国医学 | 29篇 |
肿瘤学 | 1045篇 |
出版年
2024年 | 18篇 |
2023年 | 133篇 |
2022年 | 229篇 |
2021年 | 474篇 |
2020年 | 226篇 |
2019年 | 364篇 |
2018年 | 443篇 |
2017年 | 290篇 |
2016年 | 292篇 |
2015年 | 332篇 |
2014年 | 424篇 |
2013年 | 521篇 |
2012年 | 745篇 |
2011年 | 819篇 |
2010年 | 468篇 |
2009年 | 450篇 |
2008年 | 734篇 |
2007年 | 678篇 |
2006年 | 645篇 |
2005年 | 655篇 |
2004年 | 607篇 |
2003年 | 543篇 |
2002年 | 443篇 |
2001年 | 212篇 |
2000年 | 188篇 |
1999年 | 164篇 |
1998年 | 84篇 |
1997年 | 85篇 |
1996年 | 66篇 |
1995年 | 53篇 |
1994年 | 44篇 |
1993年 | 45篇 |
1992年 | 81篇 |
1991年 | 64篇 |
1990年 | 57篇 |
1989年 | 54篇 |
1988年 | 44篇 |
1987年 | 39篇 |
1986年 | 38篇 |
1985年 | 36篇 |
1984年 | 26篇 |
1983年 | 25篇 |
1982年 | 20篇 |
1980年 | 12篇 |
1979年 | 19篇 |
1977年 | 17篇 |
1975年 | 14篇 |
1974年 | 12篇 |
1973年 | 15篇 |
1968年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
Lorenzo Franchi Alessandro Vichi Patrizia Marti Flavio Lampus Simone Guercio Annamaria Recupero Veronica Giuntini Cecilia Goracci 《Materials》2022,15(11)
In order to improve fit and comfort, a maxillary protraction facemask customized to the patient’s anatomy was produced by means of 3D face scanning, digital design and additive manufacturing. An 8-year-old patient in need of early treatment for the Class III malocclusion received a rapid palatal expander and a Petit-type facemask, whose components were digitally designed on a 3D scan of the patient’s face. For face scanning, the iPad Pro 2018 tablet (Apple, Cupertino, CA, USA) with the Bellus3D DentalPro application (Bellus3D, Campbell, CA, USA) was used. Facemask components were modelled with 3D Blender software. The rests were 3D printed in BioMed Clear biocompatible resin (Formlabs, Somerville, MA, USA), and the bar in stainless steel. For greater comfort, the internal surface of the rests was lined with a polymer gel pad (Silipos, Niagara Falls, NY, USA). The manufacturing procedure of the customized facemask is patented. The patient wore the facemask at night for a period of 9 months. The patient’s experience was evaluated with a questionnaire at 1 week, 3, 6, and 10 months of treatment. The customized facemask was well accepted by the patient and obtained the expected treatment outcome. Furthermore, 3D face scanning, 3D modelling and 3D printing allow for the manufacturing of customized facemasks with improved fit and comfort, favoring patient compliance and treatment success. 相似文献
82.
Silvia Ferri Bernardo Stefanini Lorenzo Mulazzani Margherita Alvisi Francesco Tovoli Simona Leoni Luca Muratori Tommaso Lotti Alessandro Granito Luigi Bolondi Fabio Piscaglia 《Nutrients》2022,14(12)
The role of moderate alcohol consumption in the evolution of NAFLD is still debated. The aim of this study is to evaluate the impact of current and lifelong alcohol consumption in patients with NAFLD. From 2015 to 2020, we enrolled 276 consecutive patients fulfilling criteria of NAFLD (alcohol consumption up to 140 g/week for women and 210 g/week for men). According to their current alcohol intake per week, patients were divided in: abstainers, very low consumers (C1: <70 g/week) and moderate consumers (C2). We created a new tool, called LACU (Lifetime Alcohol Consuming Unit) to estimate the alcohol exposure across lifetime: 1 LACU was defined as 7 alcohol units per week for 1 drinking year. Patients were divided into lifelong abstainers and consumers and the latter furtherly divided into quartiles: Q1-Q4. Stratification according to alcohol intake, both current and cumulative as estimated by LACU, showed that very low consumers (C1 and Q1-Q3) displayed lower frequency of cirrhosis and hepatocellular carcinoma compared to abstainers and moderate consumers (C2 and Q4). We can speculate that up to one glass of wine daily in the context of a Mediterranean diet may be a long-term useful approach in selected NAFLD patients. 相似文献
83.
Rosanna Palmeri Francesco Corallo Lilla Bonanno Simona Curr Paola Merlino Giuseppe Di Lorenzo Placido Bramanti Silvia Marino Viviana Lo Buono 《Medicine》2022,101(26)
Apathy and impulsiveness are 2 common non-motor symptoms in Parkinson disease that could occur in different periods or simultaneously. Apathy and impulsiveness could be interpreted as opposite extremes of a spectrum of motivated behavior dependent on dopaminergic dysfunction, in which, impulsivity, is a result of a hyperdopaminergic state, whereas apathy is viewed as a hypodopaminergic. The study aimed to investigate the presence of impulsiveness and other neuropsychiatric symptoms in Parkinson disease patients with apathy symptoms.Eighty-one patients with Parkinson disease were enrolled in this retrospective study. All subjects were evaluated by the Italian version of the Dimensional Apathy Scale and the Barratt Impulsiveness Scale-version 11, to assess, respectively, apathy and impulsiveness; they were divided into 2 groups (apathy and no apathy). All patients were administered also with questionnaires assessing depressive and anxious symptoms.Statistical analyses showed relevant results. In no-apathy group, education was a significant predictor on impulsiveness (attentional and motor) and apathy (executive and emotional); depression was a significant predictor on planning impulsivity and apathy.This study aimed to consider the importance of apathy and impulsivity in Parkinson disease. Although these are considered as opposite extremes of a spectrum of motivated behavior dependent on dopaminergic dysfunction, these can also occur separately. Moreover, several variables could represent important predictors of apathy and impulsiveness, such as depression. Future investigations should deepen the role of other demographics and psychological variables. 相似文献
84.
Bruno Ribeiro Ruben Offoiach Stefano Rossetti Elisa Salatin Maria Lekka Lorenzo Fedrizzi 《Materials》2022,15(9)
Anodic oxidation of CP-Ti, for production of TiO2 nanotubes, has been extensively described in terms of the electrochemical mechanism of tubular growth or the effect of the parameters on the final tube morphology. Recently, a kinetic growth model was proposed to describe the distinct morphologies of the anodic oxide layer as phases of the nanotubular development process, offering a new perspective for the tuning of nanotube production. In this work, the anodizing behavior of a CP-Ti alloy in an ethylene glycol electrolyte was investigated in light of this new model. The final morphology of the nanotubes was characterized by SEM, considering the effects of electrolyte aging, the microstructure, the applied potential difference and time on the morphological development of nanotubes. Electrolyte aging was shown to lead to a decreased dissolution effect on the oxide. The applied potential difference was shown to lead to an increased dissolution effect and more rapid nanotube growth kinetics, while time resulted in extended dissolution. Moreover, the obtained results were analyzed considering a previous study focused on the anodizing behavior of the α- and β-phases of Ti6Al4V alloy. Overall, the tube morphology resembled that obtained for the Al-containing α-phase of the Ti6Al4V alloy, but the growth kinetics were considerably slower on CP-Ti. 相似文献
85.
Ferrero A Viganò L Polastri R Muratore A Eminefendic H Regge D Capussotti L 《World journal of surgery》2007,31(8):1643-1651
Background The future remnant liver (FRL) limit for safe major hepatectomy with low risk of postoperative liver failure has not yet been
well defined.
Methods Between April 2000 and September 2004, every patient scheduled for major hepatectomy in our institution underwent CT-volumetry
of FRL. Patients with FRL <25% underwent portal vein embolization (PVE). Exclusion criteria were PVE, associated vascular
resection and liver cirrhosis. The FRL was correlated with short-term results in patients with normal liver (group A) and
those with impaired liver function secondary to neoadjuvant chemotherapy or cholestasis (bilirubin >2 mg/100 ml) (group B).
Liver dysfunction was defined as both PT <50% and serum bilirubin level >5 mg/100 ml for three or more consecutive days.
Results A total of 119 patients were analyzed, 72 in group A and 47 in group B. The FRL value was the only significant risk factor
for postoperative liver dysfunction in the univariate and multivariate analysis (p = 0.009). The FRL did not correlate with postoperative mortality and morbidity. Bilirubin and prothrombin time (PT) on days
3 and 7 were significantly correlated to FRL in both groups. In group A, patients with postoperative liver dysfunction had
a FRL<30% (3 versus 0; p = 0.005). According to receiving operator characteristic (ROC) curve analysis, a FRL value of 26.5% predicted postoperative
liver dysfunction with 66.7% sensitivity, 97.1% specificity, 50% positive predictive value (PPV), and 98.5% negative predictive
value (NPV). In group B, patients with postoperative liver dysfunction had a FRL <35% (4 versus 0; p = 0.027). According to ROC curve analysis, a FRL value of 31.05% predicted postoperative liver dysfunction with 75% sensitivity,
79.1% specificity, 25% PPV, and 97.1% NPV.
Conclusions Hepatectomy can be considered safe when FRL is >26.5% in patients with healthy liver and >31% in patients with impaired liver
function. 相似文献
86.
Marcela Durán Alexandre N. Ponezi Adelaide Faljoni-Alario Maria F. S. Teixeira Giselle Z. Justo Nelson Durán 《Medicinal chemistry research》2012,21(7):1524-1532
Violacein is a versatile pigment from a bacterium Chromobacterium violaceum that exhibits several biological activities and, at present, has gained increasing importance in industrial markets, such as in medicine, cosmetics, and textiles. In this mini-review, we aimed to describe violacein production and to explore its various biological properties in a pharmacological context, including its antioxidant, immunomodulatory, antitumoral, and antiparasitic activities. In addition, its use in the fields of cosmetics, textiles, food, toys, and insecticides has emerged as unusual potential areas of application to be discussed here. 相似文献
87.
88.
89.
90.
In patients suffering from oral cavity cancer surgical treatment is complex because it is necessary to remove carcinoma and lymph node metastasis (through a radical unilateral or bilateral neck dissection) and to reconstruct the affected area by means of free flaps. The saliva stagnation in the post-operative period is a risk factor with regard to local complications. Minor complications related to saliva stagnation (such as tissue maceration and wound dehiscence) could become major complications compromising the surgery or the reconstructive outcome. In fact the formation of oro-cutaneous fistula may cause infection, failure of the free flap, or the patient’s death with carotid blow-out syndrome. Botulinum injections in the major salivary glands, four days before surgery, temporarily reduces salivation during the healing stage and thus could reduce the incidence of saliva-related complications. Forty three patients with oral cancer were treated with botulinum toxin A. The saliva quantitative measurement and the sialoscintigraphy were performed before and after infiltrations of botulinum toxin in the major salivary glands. In all cases there was a considerable, but temporary, reduction of salivary secretion. A lower rate of local complications was observed in the post-operative period. The salivary production returned to normal within two months, with minimal side effects and discomfort for the patients. The temporary inhibition of salivary secretion in the post-operative period could enable a reduction in saliva-related local complications, in the incidence of oro-cutaneous fistulas, and improve the outcome of the surgery as well as the quality of residual life in these patients. 相似文献