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目的 本研究应用声辐射力脉冲成像(Acoustic Radiation Force Impulse ARFI)技术对慢性乙型肝炎肝硬化患者进行脾脏弹性检测和分析,探讨和对比脾脏ARFI弹性及脾脏ARFI弹性联合血小板计数(Platelet Count PC)在预测乙肝肝硬化食道静脉曲张的临床应用价值。方法 对232例慢性乙型肝炎肝硬化患者应用ARFI技术检测脾脏实时超声弹性,并测量PC,所有患者均于检测前后一周内行胃镜检查明确食管静脉曲张情况,以胃镜结果为金标准,应用受试者工作特征(receiver operating characteristic, ROC)曲线比较脾脏ARFI弹性、PC、及脾ARFI弹性联合PC诊断肝硬化食管静脉曲张的临床价值。结果 食道静脉曲张组脾脏ARFI弹性和PC分别为3.52(3.16-3.87)m/s 和62(41-88.25),无食道静脉曲张组脾脏ARFI弹性和PC分别为2.91(2.35-3.35)m/s和129.5(87.25-196.25)。脾脏ARFI弹性和PC在两组间比较的差异均具有统计学意义(P<0.001 )。单独脾脏ARFI弹性及脾脏ARFI弹性联合PC的ROC曲线下面积分别为0.76和0.83,差异具有统计学意义(P = 0.0021)。结论 脾脏ARFI弹性测值联合PC较单纯脾脏ARFI弹性能更准确的无创预测慢性乙型肝炎肝硬化食管静脉曲张的存在,具有良好的临床应用前景。  相似文献   
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《Clinical neurophysiology》2021,132(6):1312-1320
ObjectiveTo investigate the additional value of EEG functional connectivity features, in addition to non-coupling EEG features, for outcome prediction of comatose patients after cardiac arrest.MethodsProspective, multicenter cohort study. Coherence, phase locking value, and mutual information were calculated in 19-channel EEGs at 12 h, 24 h and 48 h after cardiac arrest. Three sets of machine learning classification models were trained and validated with functional connectivity, EEG non-coupling features, and a combination of these. Neurological outcome was assessed at six months and categorized as “good” (Cerebral Performance Category [CPC] 1–2) or “poor” (CPC 3–5).ResultsWe included 594 patients (46% good outcome). A sensitivity of 51% (95% CI: 34–56%) at 100% specificity in predicting poor outcome was achieved by the best functional connectivity-based classifier at 12 h after cardiac arrest, while the best non-coupling-based model reached a sensitivity of 32% (0–54%) at 100% specificity using data at 12 h and 48 h. Combination of both sets of features achieved a sensitivity of 73% (50–77%) at 100% specificity.ConclusionFunctional connectivity measures improve EEG based prediction models for poor outcome of postanoxic coma.SignificanceFunctional connectivity features derived from early EEG hold potential to improve outcome prediction of coma after cardiac arrest.  相似文献   
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BackgroundImpaired control of balance and coordinated reactions are a primary deficit of cerebellar dysfunction. As compared to other neurological patients with balance impairments, there has been little research assessing the characteristics of compensatory responses associated with falls in patients with cerebellar disease (CD).Research questionThe aim of this study was to examine the effects of cerebellar disease on compensatory balance control in response to postural perturbation. Do CD patients increase the number of steps when responding to instability because of inappropriate initial step reactions or poor control of trunk motion or both?MethodsIn this explorative study, 10 patients suffering from degenerative cerebellar ataxia and 10 age-matched healthy controls were examined. The balance recovery reactions were assessed using a lean-and-release postural perturbation method. Spatiotemporal characteristics of stepping movement and COM variables associated with torso motion were analyzed using 3D motion capture system.ResultsCD patients took multiple steps whereas matched controls generally took single steps to recover balance following perturbation. The characteristics of the initial step at the time of the fall revealed that foot reaction time, foot response time, and step distance of the initial step were similar between CD patients and matched controls. However, CD patients exhibited a shorter foot-to−COM distance, higher COM velocity, and less trunk flexion with which to attenuate their body momentum after the landing of the first step than did matched controls.SignificanceAlthough initial step responses were probably adequate, poor control of torso motion appears to be a particular problem that causes multiple-step reactions in CD patients. This observation would help to guide the development of tailored fall intervention strategies in CD patients aimed at promoting their recovery capacity in response to a pronounced balance challenge.  相似文献   
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IntroductionSeptic arthritis is a serious orthopaedic emergency that must be diagnosed and managed early to prevent devastating complications. The current gold standard for diagnosing septic arthritis is synovial fluid culture, but results are delayed by 48–72 h, and the sensitivity of the test is very low. Differentiating Septic from non-septic arthritis is vital to prevent unnecessary use of antibiotics and prevent complications. Serum Procalcitonin (PCT) is a useful marker in differentiating septic from non-septic arthritis but there are very few studies that have studied the role of synovial PCT for the same.AimTo determine the role of serum and synovial PCT in differentiating acute Septic from non-septic arthritis.Materials and methodsProspective clinical study in which 60 patients presenting with acute inflammatory arthritis (<2 weeks duration) were enrolled from May 2018 to May 2020. Serum and synovial fluid samples were drawn at presentation and routine blood investigations, synovial fluid culture sensitivity, and Procalcitonin levels were measured. Patients were divided into 3 groups, with group-1 having confirmed pyogenic, group-2 having presumed pyogenic, and group-3 having non –pyogenic patients, respectively. All data was tabulated and statistically analysed using appropriate tests.ResultsMean serum PCT values in groups 1, 2 and 3 were 1.06 ± 1.11, 0.85 ± 0.74, and 0.11 ± 0.24, respectively. Patients in the Pyogenic group (group1 and group 2) had significantly higher mean serum PCT as compared to group3 (p < 0.0001). Group 1 had higher serum PCT as compared to group 2, but the difference was not significant (p = 0.58). Mean synovial PCT in group 1, 2 and 3 were 2.42 ± 1.98, 1.89 ± 1.18, and 0.22 ± 0.40, respectively. Patients in the Pyogenic group (Group1 and Group2) had significantly higher mean synovial PCT as compared to Group 3 (p < 0.0001). Group 1 had higher mean synovial PCT as compared to group 2, but the difference was not significant (p = 0.54). The area under the ROC curve of the serum levels of PCT was 0.0.895, and the area under the ROC curve of the synovial fluid levels of PCT was 0.914, which was higher than the serum PCT level.ConclusionSerum and synovial Procalcitonin may be used as a diagnostic marker in differentiating septic from inflammatory arthritis and can help in reducing unnecessary use of antibiotics and early diagnosis and management of septic arthritis, thereby preventing complications.  相似文献   
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Quantitative susceptibility mapping (QSM) has the potential for being a biomarker for various diseases because of its ability to measure tissue susceptibility related to iron deposition, myelin, and hemorrhage from the phase signal of a T2*-weighted MRI. Despite its promise as a quantitative marker, QSM is faced with many challenges, including its dependence on preprocessing of the raw phase data, the relatively weak tissue signal, and the inherently ill posed relationship between the magnetic dipole and measured phase. The goal of this study was to evaluate the effects of background field removal and dipole inversion algorithms on noise characteristics, image uniformity, and structural contrast for cerebral microbleed (CMB) quantification at both 3T and 7T. We selected four widely used background phase removal and five dipole field inversion algorithms for QSM and applied them to volunteers and patients with CMBs, who were scanned at two different field strengths, with ground truth QSM reference calculated using multiple orientation scans. 7T MRI provided QSM images with lower noise than did 3T MRI. QSIP and VSHARP + iLSQR achieved the highest white matter homogeneity and vein contrast, with QSIP also providing the highest CMB contrast. Compared with ground truth COSMOS QSM images, overall good correlations between susceptibility values of dipole inversion algorithms and the COSMOS reference were observed in basal ganglia regions, with VSHARP + iLSQR achieving the susceptibility values most similar to COSMOS across all regions. This study can provide guidance for selecting the most appropriate QSM processing pipeline based on the application of interest and scanner field strength.  相似文献   
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We aim to assess the safety and efficacy of proxalutamide, a novel androgen receptor antagonist, for men with metastatic castration-resistant prostate cancer (mCRPC) in a multicenter, randomized, open-label, phase 2 trial. In our study, the enrolled mCRPC patients were randomized to 100, 200 and 300 mg dose groups at 1:1:1. The primary efficacy endpoint was prostate-specific antigen (PSA) response rate. The secondary endpoints included objective response rate (ORR), disease control rate (DCR) and time to PSA and radiographic progression. Safety and pharmacokinetics were also assessed. Finally, there were 108 patients from 17 centers being enrolled. By week 16, there were 13 (35.1%), 12 (36.4%) and 15 (42.9%) patients with confirmed 50% or greater PSA decline in 100 mg (n = 37), 200 mg (n = 33) and 300 mg (n = 35) groups, respectively. Among the 19 patients with target lesions at study entry, three (15.8%) had a partial response and 12 (63.2%) had stable disease. The ORRs of 20.0%, 22.2%, 0% and DCRs of 80.0%, 88.9%, 60.0% were, respectively, achieved in 100, 200 and 300 mg groups. By the maximum follow-up time of 24 weeks, there were 42.6% and 10.2% of cases experiencing PSA progression and radiographic progression, respectively. Overall, adverse events (AEs) were experienced by 94.4% of patients, most of which were mild or moderate. There were 28 patients experiencing ≥grade 3 AEs. The most common AEs were fatigue (17.6%), anemia (14.8%), elevated AST (14.8%) and ALT (13.0%), decreased appetite (13.0%). These findings preliminarily showed the promising antitumor activity of proxalutamide in patients with mCRPC with a manageable safety profile. The proxalutamide dose of 200 mg daily is recommended for future phase 3 trial (Clinical trial registration no. CTR20170177).  相似文献   
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