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51.
Filomena Napolitano Valentina Di Iorio Giuseppe Di Iorio Mariarosa Anna Beatrice Melone Fernando Gianfrancesco Francesca Simonelli 《Ophthalmic genetics》2019,40(1):39-42
Background: Extracellular matrix molecular components, previously linked to multisystem syndromes include collagens, fibrillins and laminins. Recently, we described a novel multisystem syndrome caused by the c.9418G>A p.(V3140M) mutation in the laminin alpha-5 (LAMA5) gene, which affects connective tissues of all organs and apparatus in a three generation family. In the same family, we have also reported a myopic trait, which, however, was linked to the Prolyl 4-hydroxylase subunit alpha-2 (P4HA2) gene. Results of investigation on vitreous changes and their pathogenesis are reported in the present study.Materials and Methods: Nineteen family individuals underwent complete ophthalmic examination including best-corrected visual acuity (BCVA), fundus examination, fundus photography, intraocular pressure measurement, axial length measurement using ocular biometry, Goldmann visual field examination, standard electroretinogram, SD-OCT. Segregation analysis of LAMA5 and P4HA2 mutations was performed in enrolled members.Results: The vitreous alterations fully segregated with LAMA5 mutation in both young and adult family members. Slight reduction of retinal thickness and peripheral retinal degeneration in only two patients were reported.Conclusions: In this work we showed that PVD is a common trait of LAMA5 multisystem syndrome, therefore occurring as an age-unrelated trait. We hypothesize that the p.(V3140M) mutation results in a reduction of retinal inner limiting membrane (ILM) stability, leading to a derangement in the macromolecular structure of the vitreous gel, and PVD. Further investigations will be necessary to elucidate the role of wild type and mutated LAMA5 in the pathogenesis of PVD. 相似文献
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李志道教授经过50余年临床实践研究,结合解剖学相关知识,发现委中、承山二穴在针刺深度与传统认识有所不同。其中,委中穴在刺入0. 5~0. 8寸,承山穴在刺入2. 0~3. 0寸时最易达到循经得气的效果,通过调整针尖方向还可较准确达到气至病所的效果,且针感与相应神经分布区域相吻合。该针感在某些疾病,尤其神经压迫相关症状的治疗中疗效明显,且优于传统教材所述针刺深度。 相似文献
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孤独症谱系障碍(ASD)是影响儿童健康的严重公共问题之一,以社交沟通障碍、兴趣或活动范围狭窄以及重复刻板行为为特征。近年来越来越多的研究显示,ASD患儿维生素D(VitD)水平明显低于同龄健康儿童,VitD缺乏可能与ASD的发病机制相关。本文就VitD与ASD的相关研究进行综述。 相似文献
57.
IntroductionWe aimed to assess, in patients with Parkinson's disease (PD), the association between obstructive sleep apnea (OSA), progression of motor dysfunction and the effect of OSA treatment.MethodsData were analysed from a prospective cohort study of idiopathic PD patients from a movement disorders clinic. Patients found to have OSA on polysomnography (apnea-hypopnea index [AHI] ≥15 events/h, OSA+) were offered treatment using continuous positive airway pressure (CPAP). CPAP+ was defined as an average ≥ 2 h/night use at each follow-up. Motor symptoms were assessed using the motor section of the Movement Disorder Society Unified Parkinson's Disease Rating Scale (mUPDRS) and the Timed-Up-And-Go (TUG). Follow-up times were 3, 6 and 12 months. Mixed models were constructed, adjusting for age, sex, body mass index, levodopa equivalent dose and comorbidities.ResultsWe studied 67 individuals (61.2% male) of mean age 64.7 years (SD = 10.1). Baseline mUPDRS was higher in OSA+ compared to OSA- (24.5 [13.6] vs. 16.2 [7.2], p < 0.001). Motor dysfunction increased at comparable rates in OSA- and OSA+CPAP-. However, in OSA+CPAP+, mUPDRS change was significantly lower compared to OSA- (β = −0.01 vs. 0.61, p = 0.03; p = 0.12 vs. OSA+CPAP- [β = 0.39]) and TUG change was lower compared to OSA+CPAP- (β = −0.01 vs. 0.13, p = 0.002; p = 0.05 vs. OSA- [β = 0.02]).ConclusionsIn this PD cohort, OSA was associated with higher baseline mUPDRS. In those with OSA, CPAP use was associated with stabilization of motor function (mUPDRS and TUG) over 12 months. These observations support further research to clarify the role of OSA in PD pathophysiology and motor dysfunction. 相似文献
58.
《Respiratory investigation》2022,60(1):137-145
BackgroundSome chronic obstructive pulmonary disease (COPD) patients develop hypoxemia with disease progression, with some even requiring long-term oxygen therapy (LTOT). Lung function, especially diffusing capacity, and the annual decline in PaO2, are reported to be predictive factors of chronic respiratory failure. However, the association between lung morphometry evaluated using computed tomography (CT) images and LTOT initiation is unknown.MethodsWe retrospectively evaluated the relationship between clinical indices, including pulmonary function, body mass index (BMI), and CT parameters, at baseline and LTOT initiation in two prospective COPD cohorts. In the Nara Medical University cohort (n = 76), the low attenuation area (LAA) and its fractal dimension (fractal D) were adapted as the indices for parenchymal destruction in CT images. The association between these CT measurements and LTOT initiation was replicated in the Kyoto University cohort (n = 130).ResultsIn the Nara Medical University cohort, lower BMI (hazard ratio [HR]:0.70, p = 0.006), lower % diffusing capacity (%DLCO) (HR: 0.92, p = 0.006), lower %DLCO/VA (HR, 0.90, p = 0.008), higher RV/TLC (HR, 1.26, p = 0.012), higher LAA% (HR: 1.18, p = 0.001), and lower fractal D (HR: 3.27 × 10?8, p < 0.001) were associated with LTOT initiation. Multivariate analysis in the Kyoto University cohort confirmed that lower %DLCO and lower fractal D were independently associated with LTOT initiation, whereas LAA% was not.ConclusionFractal D, which is the index for morphometric complexity of LAA in CT analysis, is predictive of LTOT initiation in COPD patients. 相似文献
59.
《Brain stimulation》2022,15(2):337-351
BackgroundAbnormalities in frontoparietal network (FPN) were observed in many neuropsychiatric diseases including substance use disorders. A growing number of studies are using dual-site-tACS with frontoparietal synchronization to engage this network. However, a computational pathway to inform and optimize parameter space for frontoparietal synchronization is still lacking. In this case study, in a group of participants with methamphetamine use disorders, we proposed a computational pathway to extract optimal electrode montage while accounting for stimulation intensity using structural and functional MRI.MethodsSixty methamphetamine users completed an fMRI drug cue-reactivity task. Four main steps were taken to define electrode montage and adjust stimulation intensity using 4x1 high-definition (HD) electrodes for a dual-site-tACS; (1) Frontal seed was defined based on the maximum electric fields (EF) predicted by simulation of HD montage over DLPFC (F3/F4 in EEG 10–10), (2) frontal seed-to-whole brain context-dependent correlation was calculated to determine connected regions to frontal seeds, (3) center of connected cluster in parietal cortex was selected as a location for placing the second set of HD electrodes to shape the informed montage, (4) individualized head models were used to determine optimal stimulation intensity considering underlying brain structure. The informed montage was compared to montages with large electrodes and classic frontoparietal HD montages (F3-P3/F4-P4) in terms of tACS-induced EF and ROI-to-ROI task-based/resting-state connectivity.ResultsCompared to the large electrodes, HD frontoparietal montages allow for a finer control of the spatial peak fields in the main nodes of the FPN at the cost of lower maximum EF (large-pad/HD: max EF[V/m] = 0.37/0.11, number of cortical sub-regions that EF exceeds 50% of the max = 77/13). For defining stimulation targets based on EF patterns, using group-level head models compared to a single standard head model results in comparable but significantly different seed locations (6.43 mm Euclidean distance between the locations of the frontal maximum EF in standard-space). As expected, significant task-based/resting-state connections were only found between frontal-parietal locations in the informed montage. Cue-induced craving score was correlated with frontoparietal connectivity only in the informed montage (r = ?0.24). Stimulation intensity in the informed montage, and not in the classic HD montage, needs 40% reduction in the parietal site to reduce the disparity in EF between stimulation sites.ConclusionThis study provides some empirical insights to montage and dose selection in dual-site-tACS using individual brain structures and functions and proposes a computational pathway to use head models and functional MRI to define (1) optimum electrode montage for targeting FPN in a context of interest (drug-cue-reactivity) and (2) proper transcranial stimulation intensity. 相似文献
60.
Jeffrey Buenaflor Parker Sommerville Hang Qian Christine Luscombe 《Macromolecular chemistry and physics.》2020,221(2)
A comparative study involving bimetallic nickel catalysts designed from disubstituted N,N,N′,N′‐tetra(diphenylphosphanylmethyl)benzene diamine bridging ligands is reported. Catalyst behavior is explored in the Kumada catalyst‐transfer polymerization (KCTP) using poly(3‐hexylthiophene) (P3HT) as the model system. The success of a controlled polymerization is monitored by analyzing monomer conversion, degree of polymerization, end‐group identity, and molecular weight distribution. The characterization of P3HT obtained from KCTP initiated with the bimetallic catalysts shows chain‐growth behavior; however, the presence of Br/Br end‐groups and broader molecular weight distribution reveals a reduced controlled polymerization compared to the commonly employed Ni(dppp)Cl2. The observed increase in intermolecular chain transfer and termination processes in KCTP initiation with the bimetallic catalysts can be attributed to a weaker Ni(0)‐π‐aryl complex interaction, which is caused by increased steric crowding of the coordination sphere. 相似文献