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991.
BackgroundMultiple appropriate use criteria (AUC) exist for the evaluation of coronary artery disease (CAD), but there is little data on the agreement between AUC from different professional medical societies. The aim of this study is to compare the appropriateness of coronary computed tomography angiography (CCTA) exams assessed using multimodality AUC from the American College of Cardiology Foundation (ACCF) versus the American College of Radiology (ACR).MethodsIn a single-center prospective cohort study from June 2014 to 2016, 1005 consecutive subjects referred for evaluation of known or suspected CAD received a contrast-enhanced CCTA. The primary outcome was the agreement of appropriateness ratings using ACCF and ACR guidelines, measured by the kappa statistic. A secondary outcome was the rate of obstructive CAD by appropriateness rating.ResultsAmong 1005 subjects, the median (5–95th percentile) age was 59 (37–76) years with 59.0% male. The ACCF criteria classified 39.6% (n = 398) appropriate, 24.2% (n = 243) maybe appropriate, and 36.2% (n = 364) rarely appropriate. The ACR guidelines classified 72.3% (n = 727) appropriate, 2.6% (n = 26) maybe appropriate, and 25.1% (n = 252) rarely appropriate. ACCF and ACR appropriateness ratings were in agreement for 55.0% (n = 553). Overall, there was poor agreement (kappa 0.27 [95% confidence interval 0.23–0.31]). By both AUC methods, a low rate of obstructive CAD was observed in the rarely appropriate exams (ACCF 7.1% [n = 26 of 364] and ACR 13.5% [n = 34 of 252]).ConclusionsCompared to ACCF criteria, the ACR guidelines of appropriateness were broader and classified significantly more CCTA exams as appropriate. The poor agreement between appropriateness ratings from the ACCF and ACR AUC guidelines evokes implications for reimbursement and future test utilization.  相似文献   
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BackgroundGait initiation and turning are common triggers for Freezing of Gait (FOG) in people with Parkinson’s disease (PD). Recently, it has been shown that closed-loop tactile feedback (CLTF) can be effective to improve turning performance in people with FOG.Research questionDoes CLTF change the preparation and execution of the first step during gait initiation?MethodsPeople (n = 36) with PD with FOG (PD + FOG) (n = 18) and without FOG (PD-FOG) (n = 18) were included in the study and performed self-initiated gait with or without CLTF under single and dual task conditions. Anticipatory postural adjustments (APAs) and step kinematics were quantified with inertial measurement units (IMUs). Muscle activity of the right and left tensor fasciae latae (TFL) was measured via EMG recordings.ResultsPD + FOG and PD-FOG did not differ in age, gender and disease duration and severity (p > 0.05). PD + FOG performed smaller APAs (F = 4.559, p = 0.04) with a higher amount of TFL co-contraction (F = 6.034, p = 0.02) compared to PD-FOG. CLTF had no effect on APAs but led to an increase in first step duration (F = 7.921, p = 0.008).ConclusionsPD + FOG had smaller APAs and higher left and right TFL co-contraction during gait initiation. CLTF did not impact preparation of the first step but led to a slower execution of the first step. We speculate that, similarly to findings from turning, CLTF might result in the participant attending more closely to the first step compared to without CLTF. Whether increased attention on gait initiation is beneficial in diminishing FOG should be investigated in more detail.  相似文献   
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《The ocular surface》2020,18(2):249-257
PurposeTo evaluate the safety and effectiveness of the intranasal tear neurostimulator (ITN) in improving dry eye symptoms assessed in a controlled adverse environment (CAE®).MethodsStudy 1: Multicenter, subject-masked, randomized-sequence, crossover design. Single intranasal (active) and extranasal (control) ITN administration during CAE exposure. Study 2: Single-arm, open-label design. Intranasal ITN administration ≥2 times/day for 45 days, CAE assessment at days 0 and 45. In both studies, upon CAE entry, and every 5 min thereafter, subjects assessed eye dryness score (visual analog scale, 0–100 mm; EDS-VAS), and ocular discomfort score (ODS; Ora Calibra™, 0–4), for ≈2 h. Study 1: when ODS was ≥3 at 2 consecutive timepoints, subjects applied ITN intranasally or extranasally for ≈3 min, and again when achieving the same ODS criteria in randomized sequence. Study 2: days 0 and 45, ITN was applied for ≈3 min employing the same ODS criteria as Study 1.ResultsStudy 1: Significantly greater pre- to post-application reductions in mean [SEM] EDS (−16.5 [1.7] vs −3.1 [1.7], P < 0.0001) and ODS (−0.93 [0.08] vs −0.34 [0.08], P < 0.0001; n = 143) with intranasal vs extranasal stimulation. Study 2: On day 0 (n = 52) and day 45 (n = 48), significant pre- to post-application reductions in mean [SEM] EDS (−15.9 [2.7] and −15.2 [2.4]; P < 0.0001), and ODS (−1.3 [0.2] and −1.3 [0.1]; P < 0.0001). Few device-related adverse events were reported, none serious.ConclusionsAcute symptom relief is significant with the ITN and remains undiminished after daily use.  相似文献   
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目的探讨重症手足口合并脑炎患儿血清及脑脊液中MMPs与TIMP-1变化,为重症手足口合并脑炎患儿早期诊断提供依据。方法以2015-01—2018-03于郑州儿童医院就诊确诊为手足口患儿100例为研究对象,其中普通型55例,重型22例,危重型23例,其中重型及危重型HFMD组均为合并神经系统受累的患儿,统称为脑炎组。统计分析患儿脑脊液蛋白、脑脊液细胞数水平及脑脊液和血清中MMP-2、MMP-9、TIMP-1水平。结果(1)重型和危重型HFMD血清和脑脊液MMP-2、MMP-9、TIMP-1水平较普通型和健康对照组显著增高,危重型增高较为显著,差异有统计学意义(P<0.05);(2)脑炎组血清MMP-2、MMP-9、TIMP-1浓度水平较普通型、健康对照组组显著增高(P<0.05);(3)相关性分析结果显示,HFMD患儿血清MMP-2、MMP-9、TIMP-1浓度水平和脑脊液MMP-2、MMP-9、TIMP-1浓度水平显著正相关,相关系数分别为(r=0.719,P=0.001;r=0.638,P=0.000;r=0.704,P=0.000);(4)血清MMP-2、MMP-9和TIMP-1浓度水平预测脑炎ROC分析,曲线下面积分别为0.95695%CI(0.919、0.994)、0.95195%CI(0.906、0.996)、0.88795%CI(0.852、0.949),最佳截断点分别为103.59、96.34、108.64,相应敏感度和特异度分别为84.4%和94.5%、93.3和87.3%、88.9%和72.7%。结论重型和危重型HFMD合并神经系统受累病例血清和脑脊液中MMP-2、MMP-9、TIMP-1水平升高明显,对于重症手足口病合并脑炎的辅助诊断在临床上具有重要的意义。  相似文献   
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Previous studies have shown that neural stem cell transplantation has the potential to treat Parkinson’s disease,but its specific mechanism of action is still unclear.Stromal cell-derived factor-1 and its receptor,chemokine receptor 4(CXCR4),are important regulators of cell migration.We speculated that the CXCR4/stromal cell-derived factor 1 axis may be involved in the therapeutic effect of neural stem cell transplantation in the treatment of Parkinson’s disease.A Parkinson’s disease rat model was injected with 6-hydroxydopamine via the right ascending nigrostriatal dopaminergic pathway,and then treated with 5μL of neural stem cell suspension(1.5×104/L)in the right substantia nigra.Rats were intraperitoneally injected once daily for 3 days with 1.25 mL/kg of the CXCR4 antagonist AMD3100 to observe changes after neural stem cell transplantation.Parkinson-like behavior in rats was detected using apomorphine-induced rotation.Immunofluorescence staining was used to determine the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Using quantitative real-time polymerase chain reaction,the mRNA expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra were measured.In addition,western blot assays were performed to analyze the protein expression of stromal cell-derived factor-1 and CXCR4.Our results demonstrated that neural stem cell transplantation noticeably reduced apomorphine-induced rotation,increased the mRNA and protein expression of stromal cell-derived factor-1 and CXCR4 in the right substantia nigra,and enhanced the immunoreactivity of tyrosine hydroxylase,CXCR4,and stromal cell-derived factor-1 in the brain.Injection of AMD3100 inhibited the aforementioned effects.These findings suggest that the stromal cell-derived factor-1/CXCR4 axis may play a significant role in the therapeutic effect of neural stem cell transplantation in a rat model of Parkinson’s disease.This study was approved by the Animal Care and Use Committee of Kunming Medical University,China(approval No.SYXKK2015-0002)on April 1,2014.  相似文献   
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