全文获取类型
收费全文 | 1517篇 |
免费 | 75篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 46篇 |
妇产科学 | 30篇 |
基础医学 | 187篇 |
口腔科学 | 16篇 |
临床医学 | 117篇 |
内科学 | 453篇 |
皮肤病学 | 14篇 |
神经病学 | 154篇 |
特种医学 | 74篇 |
外科学 | 104篇 |
综合类 | 5篇 |
一般理论 | 2篇 |
预防医学 | 78篇 |
眼科学 | 23篇 |
药学 | 100篇 |
中国医学 | 13篇 |
肿瘤学 | 177篇 |
出版年
2024年 | 3篇 |
2023年 | 10篇 |
2022年 | 18篇 |
2021年 | 45篇 |
2020年 | 33篇 |
2019年 | 32篇 |
2018年 | 36篇 |
2017年 | 32篇 |
2016年 | 30篇 |
2015年 | 41篇 |
2014年 | 58篇 |
2013年 | 69篇 |
2012年 | 104篇 |
2011年 | 113篇 |
2010年 | 59篇 |
2009年 | 64篇 |
2008年 | 81篇 |
2007年 | 93篇 |
2006年 | 106篇 |
2005年 | 109篇 |
2004年 | 112篇 |
2003年 | 78篇 |
2002年 | 65篇 |
2001年 | 18篇 |
2000年 | 14篇 |
1999年 | 20篇 |
1998年 | 14篇 |
1997年 | 13篇 |
1996年 | 9篇 |
1995年 | 11篇 |
1994年 | 9篇 |
1993年 | 4篇 |
1992年 | 10篇 |
1991年 | 9篇 |
1990年 | 15篇 |
1989年 | 7篇 |
1988年 | 7篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 6篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1979年 | 2篇 |
1975年 | 11篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1962年 | 1篇 |
排序方式: 共有1600条查询结果,搜索用时 31 毫秒
61.
Julie T-W. Wang Chiara Fabbro Enrica Venturelli Cécilia Ménard-Moyon Olivier Chaloin Tatiana Da Ros Laura Methven Antonio Nunes Jane K. Sosabowski Stephen J. Mather Martyn K. Robinson Julien Amadou Maurizio Prato Alberto Bianco Kostas Kostarelos Khuloud T. Al-Jamal 《Biomaterials》2014
Carbon nanotubes (CNTs) exhibit unique properties which have led to their applications in the biomedical field as novel delivery systems for diagnosis and therapy purposes. We have previously reported that the degree of functionalization of CNTs is a key factor determining their biological behaviour. The present study broadens the spectrum by investigating the impact of the diameter of CNTs using two series of multi-walled CNTs (MWNTs) with distinct differences in their diameters. Both MWNTs were doubly functionalized by 1,3-dipolar cycloaddition and amidation reactions, allowing the appended functional groups to be further conjugated with radionuclide chelating moieties and antibodies or antibody fragments. All constructs possessed comparable degree of functionalization and were characterized by thermogravimetric analysis, transmission electron microscopy, gel electrophoresis and surface plasmon resonance. The MWNT conjugates were radio-labelled with indium-111, which thereby enabled in vivo single photon emission computed tomography/computed tomography (SPECT/CT) imaging and organ biodistribution study using γ-scintigraphy. The narrow MWNTs (average diameter: 9.2 nm) demonstrated enhanced tissue affinity including non-reticular endothelial tissues compared to the wider MWNTs (average diameter: 39.5 nm). The results indicate that the higher aspect ratio of narrow MWNTs may be beneficial for their future biological applications due to higher tissue accumulation. 相似文献
62.
63.
Daniela Laricchiuta Laura Petrosini Fabrizio Piras Debora Cutuli Enrica Macci Eleonora Picerni Chiara Chiapponi Carlo Caltagirone Gianfranco Spalletta 《Brain structure & function》2014,219(3):793-803
Novelty Seeking (NS) and Harm Avoidance (HA) temperamental traits are related to approaching or avoiding motivational circuits relying on the integrity and functionality of distributed brain areas implicated in arousal and action. The present study verified whether and how macro- and micro-structural variations of basal ganglia are correlated with scores obtained in the NS and HA temperamental scales of the Temperament and Character Inventory by Cloninger. To this aim, 125 healthy adults aged 18–67 years of both sexes completed the Temperament and Character Inventory and underwent a high-resolution T1-weighted magnetic resonance imaging and a diffusion tensor imaging using a 3T scanner. The scores obtained in the temperamental scales were associated with volumes, mean diffusivity and fractional anisotropy measures of basal ganglia of both hemispheres separately, by using linear regression analyses. We found increased bilateral caudate and pallidum volumes associated with higher NS scores, as well as increased mean diffusivity in the bilateral putamen associated with higher HA scores. Macro- and micro-structural variations of basal ganglia regions contribute to explain the biological variance associated with NS or HA personality phenotype. The present findings evidencing some brain-temperament relationships highlight the importance of obtaining macro- and micro-structural measures in relation to individual differences. 相似文献
64.
Translocation mechanisms of chemically functionalised carbon nanotubes across plasma membranes 总被引:1,自引:0,他引:1
Lacerda L Russier J Pastorin G Herrero MA Venturelli E Dumortier H Al-Jamal KT Prato M Kostarelos K Bianco A 《Biomaterials》2012,33(11):3334-3343
Understanding the mechanisms responsible for carbon nanotube (CNT) internalisation into live cells is considered critical both from a fundamental point of view and for further engineering of CNT-based delivery systems to intracellular targets. While several studies are focused on the development of such CNT-based delivery systems, attempts to systematically elucidate the cellular uptake mechanisms of CNTs are still rather limited. The aim of the present study is to evaluate the cellular internalisation of chemically functionalised multi-walled carbon nanotubes (f-MWCNTs) in the presence of different well-known cellular uptake inhibitors. Our data reveal how f-MWCNTs are able to translocate across cell membranes of both phagocytic and non-phagocytic cell lines. We have evidenced that at least 30-50% of f-MWCNTs are taken up by cells through an energy-independent mechanism. This characteristic makes nanotubes loaded with therapeutic or diagnostic cargos extremely interesting as the release of active molecules directly into the cytoplasm increase their biological activity and therapeutic efficacy. 相似文献
65.
Maria Carmina Castiello Marita Bosticardo Nicolò Sacchetti Enrica Calzoni Elena Fontana Yasuhiro Yamazaki Elena Draghici Cristina Corsino Ileana Bortolomai Lucia Sereni Hsin-Hui Yu Paolo Uva Rahul Palchaudhuri David T. Scadden Anna Villa Luigi D. Notarangelo 《The Journal of allergy and clinical immunology》2021,147(1):309-320.e6
66.
M. Ammassari-Teule Jean Marc Milhaud Enrica Passino Leonardo Restivo Jean-Michel Lassalle 《Behavior genetics》1999,29(4):283-289
These experiments examine the influence of context manipulations on radial maze performance in C57BL/6 (C57) and DBA/2 (DBA) mice. Animals from each strain were trained in two distinct contexts—poor cuing vs rich cuing—that were sucessively switched. The results first show that C57 performed better when trained under rich cuing conditions than under poor ones, whereas DBA performed poorly under both conditions. In addition, contextual manipulations were found to produce more drastic effects in C57 than in DBA mice. That is, C57 showed a strong performance decrement following each context shift, whereas DBA mice did not. In particular, the fact that DBA mice performed similarly under rich and poor cuing conditions and also reacted mildly—or did not react—to context shifts suggests a deficit in processing contextual information, which places important constraints on their capability to form spatial representations. 相似文献
67.
Barresi V Grosso M Vitarelli E Tuccari G Barresi G 《Diseases of the colon and rectum》2007,50(10):1576-1584
Purpose It has been extensively documented that the cyclooxygenase inducible form and 15-lipoxygenase are implicated in colorectal
carcinogenesis. Nonetheless, the role of other enzymes involved in the arachidonic acid metabolism, such as 5-lipoxygenase,
in colorectal neoplasms has not been fully ascertained. This study was designed to evaluate 5-lipoxygenase expression in sporadic
colorectal adenocarcinomas by using immunohistochemistry and to analyze its potential correlations with clinicopathologic
parameters and with cyclooxygenase-2 expression.
Methods Expression of 5-lipoxygenase and cyclooxygenase-2 were evaluated by immunohistochemistry in 50 surgically resected sporadic
colorectal adenocarcinomas (28 male and 22 female patients age range, 47–88 (mean age, 69 ± 8) years). The chi-squared and
Spearman correlation tests were used to analyze correlations with clinicopathologic characteristics and to evaluate any relationships
between expression of the two enzymes. P values <0.05 were considered statistically significant.
Results 5-Lipooxygenase and cyclooxygenase-2 immunostaining was found in the cytoplasm of neoplastic cells in 41 (82 percent) and
in 43 cases (86 percent), respectively. Spearman correlation test demonstrated a positive correlation in the expression of
the two enzymes. A statistically significant correlation also was observed between 5-lipoxygenase expression and tumor stage
and lymph node metastasis, whereas no significant correlations emerged regarding cyclooxygenase-2 expression and clinicopathologic
parameters.
Conclusions Our study demonstrates that 5-lipoxygenase is expressed in colorectal adenocarcinomas in association with cyclooxygenase-2
expression. Moreover, an elevated expression of this enzyme seems to be significantly correlated with tumor aggressiveness.
Further studies would clarify the need for target therapies inhibiting both metabolic pathways in such tumors.
Supported by the grants from the University of Messina, Messina, Italy.
Presented at the meeting of the Italian Society of Anatomic Pathology and Diagnostic Cytopathology (SIAPEC), Venice, Italy,
October 4 to 5, 2006. 相似文献
68.
Yoshiko Tomita Emma Hansson Florent Mazuir Gustaf J Wellhagen Qing Xi Ooi Enrica Mezzalana Atsushi Kitamura Daisuke Nemoto Sbastien Bolze 《CTS Clinical and Translational Science》2022,15(4):1014
Imeglimin is an orally administered first‐in‐class drug to treat type 2 diabetes mellitus (T2DM) and is mainly excreted unchanged by the kidneys. The present study aimed to define the pharmacokinetic (PK) characteristics of imeglimin using population PK analysis and to determine the optimal dosing regimen for Japanese patients with T2DM and chronic kidney disease (CKD). Imeglimin plasma concentrations in Japanese and Western healthy volunteers, and patients with T2DM, including patients with mild to severe CKD with an estimated glomerular filtration rate (eGFR) greater than 14 ml/min/1.73 m2 were included in a population PK analysis. PK simulations were conducted using a population PK model, and the area under concentration‐time curve (AUC) was extrapolated with power regression analysis to lower eGFR. The influence of eGFR, weight, and age on apparent clearance and of dose on relative bioavailability were quantified by population PK analysis. Simulations and extrapolation revealed that the recommended dosing regimen based on the AUC was 500 mg twice daily (b.i.d.) for patients with eGFR 15–45 ml/min/1.73 m2, and 500 mg with a longer dosing interval was suggested for those with eGFR less than 15. Simulations revealed that differences in plasma AUCs between Japanese and Western patients at the same dose were mainly driven by a difference in the eGFR and that the plasma AUC after 1000 and 1500 mg b.i.d. in Japanese and Western patients, respectively, was comparable in the phase IIb studies. These results indicate suitable dosages of imeglimin in the clinical setting of T2DM with renal impairment. Study Highlights
- WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
- WHAT QUESTION DID THIS STUDY ADDRESS?
- WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
- HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
69.
Valeria Cannillo Roberta Salvatori Stefania Bergamini Devis Bellucci Carlo Bertoldi 《Materials》2022,15(6)
The present review deals with bioactive glasses (BGs), a class of biomaterials renowned for their osteoinductive and osteoconductive capabilities, and thus widely used in tissue engineering, i.e., for the repair and replacement of damaged or missing bone. In particular, the paper deals with applications in periodontal regeneration, with a special focus on in vitro, in vivo and clinical studies. The study reviewed eligible publications, identified on the basis of inclusion/exclusion criteria, over a ranged time of fifteen years (from 1 January 2006 to 31 March 2021). While there are many papers dealing with in vitro tests, only a few have reported in vivo (in animal) research, or even clinical trials. Regardless, BGs seem to be an adequate choice as grafts in periodontal regeneration. 相似文献
70.