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121.
目的:为临床诊断宫颈上皮内瘤变(CIN)提供理论指导及统计分析依据。方法:对病理确诊的CIN患者的阴道镜资料进行统计分析,了解CIN级别与患者年龄、宫颈糜烂程度、阴道镜图像特征之间的相关性,并判断是否存在线性关系。结果:201例不同年龄阶段CIN病理类型构成比无统计学意义(P=0.090),随着年龄的增加,CIN病理类型呈现出线性趋势(P=0.016),并且年龄与病理类型相关,但相关程度较小(P<0.005)。不同级别CIN宫颈糜烂程度分布无统计学意义(P=0.994),随着CIN程度的增加,宫颈糜烂程度未呈现出线性趋势(P=0.660),并且CIN不同病理类型与宫颈糜烂程度不相关(P=0.675)。不同级别CIN图像特征构成比有统计学意义(P<0.001),随着CIN程度的增加,阴道镜图像特征呈现出线性趋势(P<0.001),并且图像特征与病理类型相关程度较大(P<0.001)。结论:①CIN级别与患者年龄、阴道镜图像特征之间存在线性关系,与宫颈糜烂程度无关。②阴道镜在CIN的诊断中具有重要价值,但操作者需注意提高阴道镜图像鉴识能力。 相似文献
122.
Crab meat and roe are highly nutritious delicacies in China. While extensive research has been conducted for allergens derived from crab-meat, data relevant to the allergenic potential of crab roe derived proteins, of which hemocyanin is a principal contender, are almost entirely absent. Using bioinformatics prediction and IgE-binding assays, the three principal immunodominant epitopes of hemocyanin were identified and then combined as a single recombinant fusion protein (rHc). This together with the full-length recombinant protein (Hc) were expressed in Escherichia coli and subsequently identified by SDS-PAGE and immunoblotting. Ninety-five percent of our patients were found to carry rHc-specific IgE antibodies by ELISA. Dot-blot inhibition, together with ELISA inhibition studies, showed that pre-incubation of patient sera with the recombinant epitope protein could inhibit26% to 63% (mean: 50%) of IgE binding to immobilized, full-length Hc and the dose-response curve represents as a sigmoid shape. The recombinant protein (rHc) represents a versatile biologic tool with which to diagnose and investigate therapies for E. sinensis allergy. 相似文献
123.
Nurul Haiza Sapiee Ashvin Thambyah Peter A. Robertson Neil D. Broom 《The spine journal》2019,19(3):532-544
BACKGROUND CONTEXT
The cartilaginous and bony material that can be present in herniated tissue suggests that failure can involve both cartilaginous and vertebral-endplates. How structural integration is achieved across the junction between these two distinct tissue regions via its fibril and mineral components is clearly relevant to the modes of endplate failure that occur.PURPOSE
To understand how structural integration is achieved across the cartilaginous-vertebral endplate junction.STUDY DESIGN
A micro- and fibril-level structural analysis of the cartilage-vertebral endplate region was carried out using healthy, mature ovine motion segments.METHODS
Oblique vertebra-annulus-vertebra samples were prepared such that alternate layers of lamellar fibers extended from vertebra to vertebra. The endplate region of each sample was then decalcified in a targeted manner before being loaded in tension along the fiber direction to achieve incomplete rupture within the region of the endplate. The failure regions were then analyzed with differential interference contrast microscopy and scanning electron microscopy.RESULTS
Microstructural analysis revealed that failure within the endplate region was not confined to the cement line. Instead, rupture continued into the underlying vertebral endplate with bony material still attached to the now unanchored annular bundles. Ultrastructural analysis of the partially ruptured regions of the cement line revealed clear evidence of blending/interweaving relationships between the fibrils of the annular bundles, the calcified cartilage and the bone with no one pattern of association appearing dominant. These findings suggest that fibril-based structural cohesion exists across the cement line at the site of annular insertion, with strengthening via a mechanism somewhat analogous to steel-reinforced concrete. The fibrils are brought into a close intermingling association with interfibril forces mediated via the mineral component.CONCLUSIONS
This study provides clear evidence of structural connectivity across the cartilaginous-vertebral endplate junction by the intermingling of their fibrillar components and mediated by the mineral phase. This is consistent with the clinical observation that in some disc herniations bony material can be still attached to the extruded soft tissue. 相似文献124.
Wusiman Aibibula Joseph Cox Anne-Marie Hamelin Erica E. M. Moodie Aranka Anema Marina B Klein 《AIDS care》2018,30(5):643-649
Depressive symptoms are associated with poor HIV viral control and immune recovery among people living with HIV. However, no prior studies assessed this association exclusively among people co-infected with HIV-hepatitis C virus (HCV). While people with HIV only and those with HIV-HCV co-infection share many characteristics, co-infected people may become more susceptible to the effects of depressive symptoms on health outcomes. We assessed this association exclusively among people co-infected with HIV-HCV in Canada using data from the Food Security &; HIV-HCV Sub-Study (FS Sub-Study) of the Canadian Co-Infection Cohort (CCC). Stabilized inverse probability weighted marginal structural model was used to account for potential time-varying confounders. A total of 725 participants were enrolled between 2012 and 2015. At baseline, 52% of participants reported depressive symptoms, 75% had undetectable HIV viral load, and median CD4 count was 466 (IQR 300–665). People experiencing depressive symptoms had 1.32 times (95% CI: 1.07, 1.63) the risk of having detectable HIV viral load, but had comparable CD4 count to people who did not experience depressive symptoms (fold change of CD4?=?0.96, 95% CI: 0.91, 1.03). Presence of depressive symptoms is a risk factor for incomplete short-term HIV viral suppression among people co-infected with HIV-HCV. Therefore, depressive symptoms screening and related counseling may improve HIV related health outcomes and reduce HIV transmission. 相似文献
125.
Validation of a semi‐automatic co‐registration of MRI scans in patients with brain tumors during treatment follow‐up
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Anouk van der Hoorn Jiun‐Lin Yan Timothy J. Larkin Natalie R. Boonzaier Tomasz Matys Stephen J. Price 《NMR in biomedicine》2016,29(7):882-889
There is an expanding research interest in high‐grade gliomas because of their significant population burden and poor survival despite the extensive standard multimodal treatment. One of the obstacles is the lack of individualized monitoring of tumor characteristics and treatment response before, during and after treatment. We have developed a two‐stage semi‐automatic method to co‐register MRI scans at different time points before and after surgical and adjuvant treatment of high‐grade gliomas. This two‐stage co‐registration includes a linear co‐registration of the semi‐automatically derived mask of the preoperative contrast‐enhancing area or postoperative resection cavity, brain contour and ventricles between different time points. The resulting transformation matrix was then applied in a non‐linear manner to co‐register conventional contrast‐enhanced T1‐weighted images. Targeted registration errors were calculated and compared with linear and non‐linear co‐registered images. Targeted registration errors were smaller for the semi‐automatic non‐linear co‐registration compared with both the non‐linear and linear co‐registered images. This was further visualized using a three‐dimensional structural similarity method. The semi‐automatic non‐linear co‐registration allowed for optimal correction of the variable brain shift at different time points as evaluated by the minimal targeted registration error. This proposed method allows for the accurate evaluation of the treatment response, essential for the growing research area of brain tumor imaging and treatment response evaluation in large sets of patients. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
126.
127.
M2 polarization of monocytes in ankylosing spondylitis and relationship with inflammation and structural damage
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Jinzhu Zhao Wei Yuan Chunsheng Tao Peifeng Sun Zaixing Yang Weidong Xu 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2017,125(12):1070-1075
The aim of this study was to evaluate the polarization of peripheral blood monocytes in the patients with ankylosing spondylitis (AS) and to determine the correlations between monocyte polarization and inflammation and structural damage. A total of 120 AS patients, 50 rheumatoid arthritis (RA) patients and 100 healthy controls were enrolled in the study. M1 (CD68+CD192+) and M2 (CX3CR1+CD163+) monocytes were characterized by flow cytometry. Demographic, clinical, radiographic and laboratory data were collected and analyzed. A large increase in M2 (CX3CR1+CD163+) monocytes was observed in AS, and M2/M1 ratio was 7.18 ± 6.12, 2.54 ± 3.14 and 35.61 ± 20.04 in control, RA and AS, respectively. The M2/M1 ratio correlated with modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) (r = 0.565; p < 0.001), ESR (r = ?0.321; p < 0.001, CRP (r = ?0.265; p < 0.001) and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) (r = ?0.201; p = 0.028). Anti‐TNF‐α therapy induced a significant reduction in the percentage of M1 monocyte, ESR, CRP and BASDAI in AS patients. The present results demonstrated that M2 type polarized monocytes are predominant in the peripheral blood in AS and the M2/M1 ratio is correlated with structural damage (mSASSS), inflammatory biomarkers (ESR and CRP) and BASDAI. 相似文献
128.
Spatiotemporal microstructural white matter changes in diffusion tensor imaging after transient focal ischemic stroke in rats
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Won‐Beom Jung Yong Hee Han Julius Juhyun Chung Sun Young Chae Sung Hoon Lee Geun Ho Im JiHoon Cha Jung Hee Lee 《NMR in biomedicine》2017,30(6)
Structural reorganization in white matter (WM) after stroke is a potential contributor to substitute or to newly establish the functional field on the injured brain in nature. Diffusion tensor imaging (DTI) is an imaging modality that can be used to evaluate damage and recovery within the brain. This method of imaging allows for in vivo assessment of the restricted movements of water molecules in WM and provides a detailed look at structural connectivity in the brain. For longitudinal DTI studies after a stroke, the conventional region of interest method and voxel‐based analysis are highly dependent on the user‐hypothesis and parameter settings for implementation. In contrast, tract‐based spatial statistics (TBSS) allows for reliable voxel‐wise analysis via the projection of diffusion‐derived parameters onto an alignment‐invariant WM skeleton. In this study, spatiotemporal WM changes were examined with DTI‐derived parameters (fractional anisotropy, FA; mean diffusivity, MD; axial diffusivity, DA; radial diffusivity, RD) using TBSS 2 h to 6 weeks after experimental focal ischemic stroke in rats (N = 6). FA values remained unchanged 2–4 h after the stroke, followed by a continuous decrease in the ipsilesional hemisphere from 24 h to 2 weeks post‐stroke and gradual recovery from the ipsilesional corpus callosum to the external capsule until 6 weeks post‐stroke. In particular, the fibers in these areas were extended toward the striatum of the ischemic boundary region at 6 weeks on tractography. The alterations of the other parameters in the ipsilesional hemisphere showed patterns of a decrease at the early stage, a subsequent pseudo‐normalization of MD and DA, a rapid reduction of RD, and a progressive increase in MD, DA and RD with a decreased extent in the injured area at later stages. The findings of this study may reflect the ongoing processes on tissue damage and spontaneous recovery after stroke. 相似文献
129.
Besides the design freedom offered by additive manufacturing, another asset lies within its potential to accelerate product development processes by rapid fabrication of functional prototypes. The premise to fully exploit this benefit for lightweight design is the accurate structural response prediction prior to part production. However, the peculiar material behavior, characterized by anisotropy, thickness dependency and scatter, still constitutes a major challenge. Hence, a modeling approach for finite element analysis that accounts for this inhomogeneous behavior is developed by example of laser-sintered short-fiber-reinforced polyamide 12. Orthotropic and thickness-dependent Young’s moduli and Poisson’s ratios were determined via quasi-static tensile tests. Thereof, material models were generated and implemented in a property mapping routine for finite element models. Additionally, a framework for stochastic finite element analysis was set up for the consideration of scatter in material properties. For validation, thin-walled parts on sub-component level were fabricated and tested in quasi-static three-point bending experiments. Elastic parameters showed considerable anisotropy, thickness dependency and scatter. A comparison of the predicted forces with experimentally evaluated reaction forces disclosed substantially improved accuracy when utilizing the novel inhomogeneous approach instead of conventional homogeneous approaches. Furthermore, the variability observed in the structural response of loaded parts could be reproduced by the stochastic simulations. 相似文献
130.
《Vaccine》2016,34(14):1680-1687
Atroxlysin-I (Atr-I) is a hemorrhagic snake venom metalloproteinase (SVMP) from Bothrops atrox venom, the snake responsible for the majority of bites in the north region of South America. SVMPs like Atr-I produce toxic effects in victims including hemorrhage, inflammation, necrosis and blood coagulation deficiency. Mapping of B-cell epitopes in SVMPs might result in the identification of non-toxic molecules capable of inducing neutralizing antibodies and improving the anti-venom therapy. Here, using the SPOT-synthesis technique we identified two epitopes located in the N-ter region of Atr-I (AtrEp1—22YNGNSDKIRRRIHQM36; and AtrEp2—55GVEIWSNKDLINVQ68). Based on the sequence of AtrEp1 and AtrEp2 a third peptide named Atr-I biepitope (AtrBiEp) was designed and synthesized (23NGNSDKIRRRIH34GG55GVEIWSNKDLINVQ68). AtrBiEp was used to immunize BALB/c mice. Anti-AtrBiEp serum cross-reacted against Atr-I in western blot and was able to fully neutralize the hemorrhagic activity of Atr-I. Our results provide a rational basis for the identification of neutralizing epitopes on Atr-I snake venom toxin and show that the use of synthetic peptides could improve the generation of immuno-therapeutics. 相似文献