全文获取类型
收费全文 | 1478篇 |
免费 | 150篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 49篇 |
妇产科学 | 11篇 |
基础医学 | 325篇 |
口腔科学 | 30篇 |
临床医学 | 155篇 |
内科学 | 247篇 |
皮肤病学 | 18篇 |
神经病学 | 149篇 |
特种医学 | 95篇 |
外国民族医学 | 2篇 |
外科学 | 250篇 |
综合类 | 10篇 |
预防医学 | 121篇 |
眼科学 | 20篇 |
药学 | 60篇 |
中国医学 | 1篇 |
肿瘤学 | 68篇 |
出版年
2022年 | 11篇 |
2021年 | 19篇 |
2020年 | 15篇 |
2019年 | 21篇 |
2018年 | 39篇 |
2017年 | 27篇 |
2016年 | 30篇 |
2015年 | 41篇 |
2014年 | 45篇 |
2013年 | 76篇 |
2012年 | 67篇 |
2011年 | 58篇 |
2010年 | 36篇 |
2009年 | 56篇 |
2008年 | 58篇 |
2007年 | 69篇 |
2006年 | 56篇 |
2005年 | 73篇 |
2004年 | 62篇 |
2003年 | 60篇 |
2002年 | 62篇 |
2001年 | 57篇 |
2000年 | 47篇 |
1999年 | 40篇 |
1998年 | 36篇 |
1997年 | 33篇 |
1996年 | 24篇 |
1995年 | 18篇 |
1994年 | 16篇 |
1993年 | 17篇 |
1992年 | 27篇 |
1991年 | 26篇 |
1990年 | 27篇 |
1989年 | 22篇 |
1988年 | 18篇 |
1987年 | 22篇 |
1986年 | 18篇 |
1985年 | 15篇 |
1984年 | 9篇 |
1981年 | 11篇 |
1980年 | 11篇 |
1978年 | 12篇 |
1975年 | 11篇 |
1974年 | 16篇 |
1973年 | 17篇 |
1972年 | 8篇 |
1971年 | 9篇 |
1969年 | 10篇 |
1968年 | 18篇 |
1966年 | 9篇 |
排序方式: 共有1639条查询结果,搜索用时 15 毫秒
991.
Cuiru Sun Felix Nolte Kyle H. Y. Cheng Barry Vuong Kenneth K. C. Lee Beau A. Standish Brian Courtney Thomas R. Marotta Adrian Mariampillai Victor X. D. Yang 《Biomedical optics express》2012,3(10):2600-2610
Feasibility of detecting intravascular flow using a catheter based endovascular
optical coherence tomography (OCT) system is demonstrated in a porcine carotid
model in vivo. The effects of A-line density, radial distance,
signal-to-noise ratio, non-uniform rotational distortion (NURD), phase stability
of the swept wavelength laser and interferometer system on Doppler shift
detection limit were investigated in stationary and flow phantoms. Techniques
for NURD induced phase shift artifact removal were developed by tracking the
catheter sheath. Detection of high flow velocity (~51 cm/s) present in the
porcine carotid artery was obtained by phase unwrapping techniques and compared
to numerical simulation, taking into consideration flow profile distortion by
the eccentrically positioned imaging catheter. Using diluted blood in saline
mixture as clearing agent, simultaneous Doppler OCT imaging of intravascular
flow and structural OCT imaging of the carotid artery wall was feasible. To our
knowledge, this is the first in vivo demonstration of Doppler
imaging and absolute measurement of intravascular flow using a rotating fiber
catheter in carotid artery.OCIS codes: (170.4500) Optical coherence tomography, (170.3880) Medical and biological imaging, (280.3340) Laser Doppler velocimetry, (120.5050) Phase measurement 相似文献
992.
993.
994.
Winkler S Reimann-Berg N Murua Escobar H Loeschke S Eberle N Höinghaus R Nolte I Bullerdiek J 《Cancer Genetics and Cytogenetics》2006,169(2):154-158
The dog is a well-accepted model for prostate cancer in man because of the striking similarities between both species with respect to the clinical course of the disease as well as to its similar histopathology. Cytogenetic investigations of human prostate cancers has revealed the frequent occurrence of trisomies 7, 8, and 17. In this report, we present a case of prostate carcinoma in a dog characterized by polysomy 13 as the sole cytogenetic abnormality. Along with the known homology between canine chromosome 13 and human chromosome 8 these findings suggest that a homologous area on both chromosomes plays a crucial role in subsets of prostate cancer in both species. 相似文献
995.
Noise reduction in magnetocardiography by singular value decomposition and independent component analysis 总被引:2,自引:2,他引:0
DiPietroPaolo D Müller HP Nolte G Erné SN 《Medical & biological engineering & computing》2006,44(6):489-499
In the routine recording of magnetocardiograms (MCGs), it is necessary to underline the problem of noise cancellation. Source separation has often been suggested to solve this problem. In this paper, blind source separation (BSS), by means of singular value decomposition (SVD) and independent component analysis (ICA), was used for noise reduction in MCG data to improve the signal to noise ratio. Special techniques, based on statistical parameters, for identifying noise and disturbances, have been introduced to automatically eliminate noise-related and disturbance-related components before reconstructing cleaned data sets. The results show that ICA and SVD can detect and remove a variety of noise and artefact sources from MCG data, as well as from stress MCG. 相似文献
996.
van den Beucken JJ Vos MR Thüne PC Hayakawa T Fukushima T Okahata Y Walboomers XF Sommerdijk NA Nolte RJ Jansen JA 《Biomaterials》2006,27(5):691-701
This study describes the fabrication of two types of multilayered coatings onto titanium by electrostatic self-assembly (ESA), using deoxyribosenucleic acid (DNA) as the anionic polyelectrolyte and poly-d-lysine (PDL) or poly(allylamine hydrochloride) (PAH) as the cationic polyelectrolyte. Both coatings were characterized using UV-vis spectrophotometry, atomic force microscopy (AFM), X-ray photospectroscopy (XPS), contact angle measurements, Fourier transform infrared spectroscopy (FTIR), and for the amount of DNA immobilized. The mutagenicity of the constituents of the coatings was assessed. Titanium substrates with or without multilayered DNA-coatings were used in cell culture experiments to study cell proliferation, viability, and morphology. Results of UV-vis spectrophotometry, AFM, and contact angle measurements clearly indicated the progressive build-up of the multilayered coatings. Furthermore, AFM and XPS data showed a more uniform build-up and morphology of [PDL/DNA]-coatings compared to [PAH/DNA]-coatings. DNA-immobilization into both coatings was linear, and approximated 3microg/cm(2) into each double-layer. The surface morphology of both types of multilayered DNA-coatings showed elevations in the nanoscale range. No mutagenic effects of DNA, PDL, or PAH were detected, and cell viability and morphology were not affected by the presence of either type of multilayered DNA-coating. Still, the results of the proliferation assay revealed an increased proliferation of primary rat dermal fibroblasts on both types of multilayered DNA-coatings compared to non-coated controls. The biocompatibility and functionalization of the coatings produced here, will be assessed in subsequent cell culture and animal-implantation studies. 相似文献
997.
Sublingual immunotherapy: a comprehensive review 总被引:8,自引:0,他引:8
Cox LS Larenas Linnemann D Nolte H Weldon D Finegold I Nelson HS 《The Journal of allergy and clinical immunology》2006,117(5):1021-1035
Sublingual immunotherapy (SLIT) has been used with increasing frequency in Europe and is viewed with increasing interest by allergists in the United States. To address this interest, a Joint Task Force of the American College of Allergy, Asthma and Immunology and the American Academy of Allergy, Asthma and Immunology's Immunotherapy and Allergy Diagnostic Committees reviewed the available literature on SLIT and prepared this report. The task force concluded that despite clear evidence that SLIT is an effective treatment, many questions remained unanswered, including effective dose, treatment schedules, and overall duration of treatment. Until these have been determined, an assessment of the cost/benefit ratio of the treatment cannot be made. SLIT does appear to be associated with few serious side effects, but it has not been administered in high-risk asthmatic patients, nor in the studies reviewed has it been administered as a mixture of non-cross-reacting allergens. Furthermore, there is currently no allergy extract approved for this use in the United States, nor is there a Current Procedural Terminology code for billing purposes. All of these factors should be given careful consideration by anyone contemplating initiating SLIT treatment for their allergic patients. 相似文献
998.
Hungerer S Nolte D Botzlar A Messmer K 《Artificial cells, blood substitutes, and immobilization biotechnology》2006,34(5):455-471
The hemoglobin based oxygen carrier (HBOC) Diaspirin Crosslinked Hemoglobin (DCLHb) has been developed to substitute not only the blood volume, but also to restore the oxygen-carrying properties of blood during hemorrhagic shock. However, it has been suggested that HBOCs may enhance the formation of free oxygen radicals through the release of free iron ions via the Haber-Weiss reaction.The aim of this study was to investigate the effects of DCLHb on the microcirculation, leukocyte-endothelial cell interaction and local tissue oxygenation in striated skin muscle of Syrian golden hamsters during and after resuscitation from hemorrhagic shock. In particular we focused on the local tissue oxygenation after resuscitation with DCLHb (hemoglobin content 10 g%) compared to resuscitation using autologous blood diluted to a hemoglobin content of 10 g%. Hemorrhagic shock was induced for 45 minutes by bleeding the animals at a rate of 33 ml/kg BW maintaining a mean arterial pressure of 30 +/- 5 mmHg. Animals were resuscitated either with 33 ml/kg BW 6% Dextran-60.000 or with 10 g% DCLHb. The control group received shed blood diluted with Ringers to a hemoglobin content of 10 g%. Intravital microscopy was used for investigation of the microcirculatory parameters and a multiwire platinum surface electrode for measurement of local tissue pO2 in striated skin muscle in the dorsal skinfold chamber of Syrian golden hamsters.Resuscitation from hemorrhagic shock with 10 g% AUB revealed significant increase of leukocytes rolling in postcapillary venules at 30 to 120 minutes after resuscitation compared to baseline values. DCLHb turned out to reduce the number of firmly adherent leukocytes after resuscitation compared to 10 g% AUB. Microvascular permeability as an indicator for functional endothelial integrity revealed no significant differences between the groups. DCLHb and 10 g% AUB led to a significant increase in local tissue oxygenation after resuscitation from hemorrhagic shock. However, 10 g% AUB turned out to be most effective to restore the local tissue pO2 compared to Dx-60.Our findings indicate that DCLHb restores microvascular perfusion after critical hemorrhagic shock as efficient as Dx-60 and 10 g% AUB. The absence of enhanced leukocyte-endothelium interaction after resuscitation with DCLHb implies that this HBOC does not exacerbate formation of oxygen free radicals during reperfusion. DCLHb effectively increases local tissue pO2 after resuscitation from hemorrhagic shock; however, not as effectively as 10 g% AUB. 相似文献
999.
Hölzle F Kesting MR Nolte D Loeffelbein DJ Swaid S Wolff KD 《The British journal of oral & maxillofacial surgery》2006,44(1):57-59
The radial forearm flap is a standard method for the reconstruction of intraoral defects of soft tissues. We report the case of a middle-aged man who developed ischaemia in three fingers after a fasciocutaneous radial flap had been raised. The preoperative Allen test to diagnose occlusion of radial or ulnar artery was satisfactory. Soon after the operation the patient resumed smoking and four weeks later he developed ulcers on the thumb, index, and middle fingers. Only after he had stopped smoking and been given acetylsalicylic acid and heparin did blood flow and capillary hemoglobin oxygenation increase. As a result, his radial fingers recovered completely. 相似文献
1000.