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ObjectivesDonor-specific cell-free DNA shows promise as a noninvasive marker for allograft rejection, but as yet has not been validated in both adult and pediatric recipients. The study objective was to validate donor fraction cell-free DNA as a noninvasive test to assess for risk of acute cellular rejection and antibody-mediated rejection after heart transplantation in pediatric and adult recipients.MethodsPediatric and adult heart transplant recipients were enrolled from 7 participating sites and followed for 12 months or more with plasma samples collected immediately before all endomyocardial biopsies. Donor fraction cell-free DNA was extracted, and quantitative genotyping was performed. Blinded donor fraction cell-free DNA and clinical data were analyzed and compared with a previously determined threshold of 0.14%. Sensitivity, specificity, negative predictive value, positive predictive value, and receiver operating characteristic curves were calculated.ResultsA total of 987 samples from 144 subjects were collected. After applying predefined clinical and technical exclusions, 745 samples from 130 subjects produced 54 rejection samples associated with the composite outcome of acute cellular rejection grade 2R or greater and pathologic antibody-mediated rejection 2 or greater and 323 healthy samples. For all participants, donor fraction cell-free DNA at a threshold of 0.14% had a sensitivity of 67%, a specificity of 79%, a positive predictive value of 34%, and a negative predictive value of 94% with an area under the curve of 0.78 for detecting rejection. When analyzed independently, these results held true for both pediatric and adult cohorts at the same threshold of 0.14% (negative predictive value 92% and 95%, respectively).ConclusionsDonor fraction cell-free DNA at a threshold of 0.14% can be used to assess for risk of rejection after heart transplantation in both pediatric and adult patients with excellent negative predictive value.  相似文献   
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Current care for patients with follicular lymphoma (FL) offers most of them long-term survival. Improving it further will require careful patient selection. This review focuses on predictive biomarkers (ie, those whose outcome correlations depend on the treatment strategy) in FL, because awareness of what patient subsets benefit most or least from each therapy will help in this task. The first part of this review aims to summarize what biomarkers are predictive in FL, the magnitude of the effect and the quality of the evidence. We find predictive biomarkers in the setting of (a) indication of active treatment, (b) front-line induction (use of anthracyline-based regimens, CHOP vs bendamustine, addition of rituximab), (c) post-(front-line)induction (rituximab maintenance, radioimmunotherapy), and (d) relapse (hematopoietic stem cell transplant) and targeted agents. The second part of this review discusses the challenges of precision medicine in FL, including (a) cost, (b) clinical relevance considerations, and (c) difficulties over the broad implementation of biomarkers. We then provide our view on what biomarkers may become used in the next few years. We conclude by underscoring the importance of assessing the potential predictiveness of available biomarkers to improve patient care but also that there is a long road ahead before reaching their broad implementation due to remaining scientific, technological, and economic hurdles.  相似文献   
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There has been an increase in the number of assessment instruments for non-suicidal self-injury (NSSI). However, previous reviews are inconsistent and do not provide a comprehensive psychometric assessment of the instruments. This study aimed to systematically assess and compare the psychometric properties of clinically relevant instruments to measure NSSI in any population. Through a systematic review guided by COSMIN and PRISMA, two searches were conducted in English and Spanish in February 2020 in 13 databases including grey literature. Of the 7,813 initial records, 152 validations were extracted. From these, 83 instruments (22 versions or adaptations) were excluded for not measuring NSSI, having no potential clinical utility or not including psychometric properties. Finally, 26 (22 versions, 35 adaptations and 19 creations) instruments measuring NSSI were included. Predominantly, the studies were North American self-reports in English for community adolescents, adaptations or versions emanating from a small number of instruments. Twenty-six indicators were categorized to assess NSSI. The most frequent instruments are structured interviews, and their indicators were related to NSSI function and topography. Evidence of validity and reliability was positive but limited. Despite the high number of instruments and diversity of evaluations, we found no instrument with sufficient evidence for clinical assessment. Findings broadly overview NSSI assessment instruments' current use and future improvement in clinical and research settings.  相似文献   
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目的 汉化进食障碍患者家庭顺应量表,并检验其信效度。方法 根据Brislin翻译模式将量表翻译成中文,通过专家函询和预调查对量表进行文化调适和修订。将量表应用于300例进食障碍患者照顾者检验信效度。结果 中文版进食障碍患者家庭顺应量表的量表水平内容效度指数为0.918。探索性因子分析结果显示5个因子可解释总变异量的49.862%。量表的各维度得分与量表总分呈中高度相关,各维度得分之间呈中低度相关或不相关。量表总Cronbach′s α为0.877,重测信度为0.883。结论 中文版进食障碍患者家庭顺应量表具有较好的信效度,可用于测量进食障碍患者的家庭顺应情况。  相似文献   
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目的:评估加拿大问题赌博指数中文版(CPGI-C)的效度和信度。方法:选取43例匿名戒赌会成员和202例正常成人为研究对象,将其随机分为两半,分别进行探索性因子分析和验证性因子分析;以赌博相关认知量表(GRCS-C)、Barratt冲动性人格问卷(BIS-11)、抑郁自评量表(SDS)、网络成瘾量表修订版(CIAS-R)和DSM-IV多重反应问卷(DSM-IV-MR)作为效标工具;以受试者工作特征曲线(ROC)评估量表区分问题赌博者的特异度与灵敏度。2周后有5例匿名戒赌会成员和31例正常成人完成重测。结果:CPGI-C的问题赌博指数(PGSI)分量表共9个条目,探索性因子分析得出1个主成分因子,可解释总方差的74.3%;验证性因子分析显示,单因子结构模型的拟合指标良好(χ~2=2.087,CFI=0.926,TLI=0.963,GFI=0.926,IFI=0.978,NFI=0.958, RMSEA=0.094,SRMR=0.032);CPGI总分与各效标量表的总分均呈正相关(r=0.48~0.82,均P<0.001);ROC曲线下面积为0.962,划界分为9.5。CPGI-C的...  相似文献   
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BackgroundSmartphones are increasingly recognized as the future technology for clinical gait assessment.ResearchQuestion: To determine the concurrent validity of gait parameters obtained using the smartphone technology and application in a group of patients with musculoskeletal pathologies.MethodsPatients with knee, lower back, hip, or ankle pain were included in the study (n = 72). Spatiotemporal outcomes were derived from the walkway and the smartphone simultaneously. Pearson’s correlations and limits of agreement (LoA) determined the association between the two methods.ResultsCadence and gait cycle time showed excellent correlation and agreement between the smartphone and the walkway (cadence: r = 0.997, LoA=1.4%, gait cycle time: r = 0.996, LoA = 1.6%). Gait speed, double-limb support and left and right step length demonstrated strong correlations and moderate agreement between methods (gait speed: r = 0.914, LoA=15.4%, left step length: r = 0.842, LoA = 17.0%, right step length: r = 0.800, LoA=16.4%). The left and right measures of single-limb support and stance percent showed a consistent 4% bias across instruments, yielding moderate correlation and very good agreement between the smartphone and the walkway (r = 0.532, LoA = 9% and r = 0.460, LoA=9.8% for left and right single-limb support; r = 0.463, LoA = 5.1% and r = 0.533, LoA = 4.4% for left and right stance).Significance: The examined application appears to be a valid tool for gait analysis, providing clinically significant metrics for the assessment of patients with musculoskeletal pathologies. However, additional studies should examine the technology amongst patients with severe gait abnormalities.  相似文献   
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