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101.
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Clinical Oral Investigations - Periodontal disease is prevalent in patients with chronic kidney disease (CKD) and potentially associated with kidney function decline. However, it is uncertain...  相似文献   
103.
This research explores the feasibility of using motor electrical feedback to estimate temperature rise during a surgical bone grinding procedure. High-speed bone grinding is often used during skull base neurosurgery to remove cranial bone and approach skull base tumors through the nasal corridor. Grinding-induced heat could propagate and potentially injure surrounding nerves and arteries, and therefore, predicting the temperature in the grinding region would benefit neurosurgeons during the operation. High-speed electric motors are controlled by pulse-width-modulation (PWM) to alter the current input and thus maintain the rotational speed. Assuming full mechanical to thermal power conversion in the grinding process, PWM can be used as feedback for heat generation and temperature prediction. In this study, the conversion model was established from experiments under a variety of grinding conditions and an inverse heat transfer method to determine heat flux. Given a constant rotational speed, the heat conversion was represented by a linear function, and could predict temperature from the experimental data with less than 20% errors. Such results support the advance of this technology for practical application.  相似文献   
104.
LIM-kinase 1 (LIMK1) regulates actin cytoskeletal reorganization by phosphorylating and inactivating actin-depolymerizing factor and cofilin. We examined the role of LIMK1 in brain-derived neurotrophic factor (BDNF)-induced neuritogenesis in primary-cultured rat cortical neurons. Knockdown of LIMK1 or expression of a kinase-dead LIMK1 mutant suppressed BDNF-induced enhancement of primary neurite formation. By contrast, expression of an active form of LIMK1 promoted primary neuritogenesis in the absence of BDNF. BDNF-induced neuritogenesis was inhibited by KN-93, an inhibitor of Ca2+/calmodulin-dependent protein kinases (CaMKs), but not by STO-609, an inhibitor of CaMK-kinase (CaMKK). CaMKK activity is required for the activation of CaMKI and CaMKIV, but not CaMKII, which suggests that CaMKII is principally involved in BDNF-induced enhancement of neuritogenesis. Knockdown of CaMKIIβ, but not CaMKIIα, suppressed BDNF-induced neuritogenesis. Active CaMKIIβ promoted neuritogenesis, and this promotion was inhibited by knockdown of LIMK1, indicating that CaMKIIβ is involved in BDNF-induced neuritogenesis via activation of LIMK1. Furthermore, in vitro kinase assays revealed that CaMKIIβ phosphorylates LIMK1 at Thr-508 in the kinase domain and activates the cofilin-phosphorylating activity of LIMK1. In summary, these results suggest that CaMKIIβ-mediated activation of LIMK1 plays a crucial role in BDNF-induced enhancement of primary neurite formation.  相似文献   
105.
Objectives:To evaluate the condyle-fossa relationship in adolescents with various skeletal patterns using cone-beam computed tomography (CBCT).Materials and Methods:CBCT images obtained in 120 adolescent patients were used for this study. The patients were divided into 3 groups according to 3 criteria: (1) age (early, middle, and late adolescence); (2) facial height ratio or Jarabak quotient (hyperdivergent, normodivergent, and hypodivergent); and (3) ANB classification (Class I, Class II, and Class III). Temporomandibular joint space (TMJS: AS, anterior space; SS, superior space; PS, posterior space; MS, medial space; LS, lateral space), width and depth of the condyle (MLT, mediolateral thickness; APT, anteroposterior thickness), articular slope (ArS) and vertical height of the fossa (VHF) were measured and compared using CBCT.Results:Differences in condyle-fossa relationships were not significantly different between male and female adolescents, but were significantly different (P < .05) between left and right sides. The mean values showed no statistical differences according to age and skeletal pattern. Most measurements in the sagittal view showed that SS was the greatest, and the mean ratio of AS to SS to PS was 1.00 to 1.27 to 1.19, respectively. The mean values of coronal MS and LS were not significantly different.Conclusions:There were almost no statistical differences in the TMJS in adolescents across various factors except between left and right sides.  相似文献   
106.
107.
Sun  Haoyun  Du  Minquan  Tai  Baojun  Chang  Shuli  Wang  Yixuan  Jiang  Han 《Clinical oral investigations》2020,24(12):4403-4412
Clinical Oral Investigations - The purpose of this study was to assess periodontal health conditions among 55- to 74-year-old Chinese people and to analyze the factors associated with periodontal...  相似文献   
108.

Introduction

Self-assessment is a way of improving technical capabilities without the need for trainer feedback. It can identify areas for improvement and promote professional medical development. The aim of this review was to identify whether selfassessment is an accurate form of technical skills appraisal in general surgery.

Methods

The PubMed, MEDLINE®, Embase and Cochrane databases were searched for studies assessing the reliability of self-assessment of technical skills in general surgery. For each study, we recorded the skills assessed and the evaluation methods used. Common endpoints between studies were compared to provide recommendations based on the levels of evidence.

Results

Twelve studies met the inclusion criteria from 22,292 initial papers. There was no level 1 evidence published. All papers compared the correlation between self-appraisal versus an expert score but differed in the technical skills assessment and the evaluation tools used. The accuracy of self-assessment improved with increasing experience (level 2 recommendation), age (level 3 recommendation) and the use of video playback (level 3 recommendation). Accuracy was reduced by stressful learning environments (level 2 recommendation), lack of familiarity with assessment tools (level 3 recommendation) and in advanced surgical procedures (level 3 recommendation).

Conclusions

Evidence exists to support the reliability of self-assessment of technical skills in general surgery. Several variables have been shown to affect the accuracy of self-assessment of technical skills. Future work should focus on evaluating the reliability of self-assessment during live operating procedures.  相似文献   
109.
A non-human primate antiserum was prepared to acute lymphoblastic leukemia of T-cell phenotype (T-ALL) and, after absorptions with normal blood elements, reacted by immunofluorescence and microcytotoxicity to all the T-ALL tested. In addition, the antiserum reacted with cells from about 70% of the common ALL studied and immunoprecipitated the common ALL antigen of 100,000 daltons. However, when the anti-T-ALL serum was absorbed with with lymphoblasts from common ALL, it failed to react with common ALL lymphoblasts, yet reacted significantly with cells from patients with T-ALL phenotype and defined a 100,000-dalton membrane component not found on common ALL lymphoblasts. In addition, sequential immunoprecipitation of 125I-labeled T-ALL membranes by anti- common-ALL serum followed by anti-T-ALL serum detected the T-ALL membrane component of 100,000 daltons that was not found on common ALL. Thus, our results demonstrate the presence of of a unique human T-ALL antigen present on all T-ALL distinct from the common ALL antigen.  相似文献   
110.
Fecal based tests have limited diagnostic values in detecting adenomatous polyps, the precursor lesions to colorectal cancer (CRC). Surface enhanced Raman spectroscopy (SERS) using silver nanoparticles as substrate is a multiplexed analytical technique capable of detecting biomolecules with high sensitivity. This study utilizes SERS to analyze blood plasma for detecting both CRC and adenomatous polyps for the first time. Blood plasma samples are collected from healthy control subjects and patients diagnosed with adenomas and CRC. Using a real-time Raman system, SERS spectra for blood plasma samples are measured in 1 s. The collected SERS spectra are analyzed with partial least squares-discriminant analysis. Classification of normal versus CRC plus adenomatous polyps achieved diagnostic sensitivity of 86.4% and specificity of 80%. The results suggest that blood plasma SERS analysis could be a potential screening test to detect both CRC and adenomas.OCIS codes: (240.6695) Surface-enhanced Raman scattering, (170.1470) Blood or tissue constituent monitoring, (170.5660) Raman spectroscopy, (170.4580) Optical diagnostics for medicine  相似文献   
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