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951.
目的/意义 利用基于多源数据融合的机器学习算法,预测缺血性脑卒中患者的临床药物治疗风险。方法/过程 基于国际脑卒中试验数据集,融合患者人口统计学、生命体征检查及临床药物治疗数据,利用随机森林、逻辑回归和梯度提升决策树算法预测用药风险。结果/结论 3种算法在预测性能方面都表现较好,其中梯度提升决策树的召回率达到91.6%,曲线下面积为0.832,效果最佳。多源数据融合的机器学习算法在缺血性脑卒中用药风险预警中具有良好适用性。  相似文献   
952.
介绍成果导向教育教学理念,详细阐述“线上+线下”混合式教学设计过程,包括设计流程、教学目标、课程实施、学习成果及教学评价等,以期激发学生学习兴趣,提高教学效果。  相似文献   
953.
ObjectiveTo investigate whether the radiographic results are affected by cage position in single‐level transforaminal lumbar interbody fusion (TLIF).MethodBetween January 2016 and June 2018, 130 patients (62 males and 68 females, average age: 55.28 ± 10.11 years) who underwent single‐level TLIF were analyzed retrospectively. Standing lateral radiographs of the lumbar spine were collected and evaluated preoperatively, postoperatively, and at the time of last follow‐up. Cage position in the fused segment was recorded using a central point ratio (CPR), which indicated the cage position. CPR is calculated by dividing the distance between the cage center point and the posterior extent of the superior endplate of the inferior vertebra by the length of the superior endplate of the inferior vertebra. Based on cage positions, the patients were divided into three groups: Anterior Group (n = 38); Middle Group (n = 68); and Posterior Group (n = 24). Segmental lumbar lordosis (SLL), foraminal height (FH), posterior disc height (PDH), and anterior disc height (ADH) were evaluated. A subanalysis was also performed on cage height within each group.ResultsThe average follow‐up time of the patients was 35.20 ± 4.43 months. The mean values of CPR in Anterior Group, Middle Group, and Posterior Group were 0.64, 0.51, and 0.37, respectively. The FH, PDH, and ADH were significantly increased after TLIF in all groups (P < 0.05). There were significant differences in increase of SLL in Anterior Group (4.4°) and Middle Group (3.0°), but not in Posterior Group (0.3°). Furthermore, in the comparison of the three groups, the increase of SLL, FH, and PDH was statistically different (P < 0.05), while not for ADH (P > 0.05). The significant correlations in surgery were: CPR and ΔSLL (r = 0.584, P < 0.001), CPR and ΔFH (r = −0.411, P < 0.001), and CPR and ΔPDH (r = −0.457, P < 0.001). However, ADH had a positive correlation with cage height when the cage was located in anterior and middle of the endplate. Moreover, cage height had a positive correlation with SLL when the cage was located anteriorly and had a negative correlation with SLL when the cage was located posteriorly. FH and PDH both had a positive correlation with cage height in any cage position.ConclusionThe cage located in different positions has different effects on radiographic results in single‐level TLIF. A thicker cage located anteriorly will gain maximum SLL and avoid the reduction of FH and PDH.  相似文献   
954.
ObjectiveTo compare the clinical results of two surgical techniques, Wiltse approach and conventional transforaminal interbody fusion, for the treatment of unstable thoracolumbar fracture associated with traumatic intervertebral disc lesion (TIDL).MethodsA total of 76 patients with unstable thoracolumbar fracture associated with TIDL treated by posterior pedicle screw fixation and transforaminal thoracolumbar interbody fusion from June 2010 and July 2016 were reviewed retrospectively. These patients including 48 male and 28 female patients were divided into Wiltse approach transforaminal thoracolumbar interbody fusion (W‐TLIF) group (n = 38) and conventional transforaminal thoracolumbar interbody fusion (C‐TLIF) group (n = 38). Patients were followed up for about 33 months. Clinical and radiological records, kyphotic angle, fractured vertebral body height, visual analogue score (VAS), Oswestry Disability Index (ODI), complications, neurological improvement and fusion rate were compared between two groups.ResultsAll patients underwent posterior surgery successfully. Blood loss, operation time and hospital stay in the W‐TLIF group was 437.84 ± 143.98 ml, 118.64 ± 20.55 min and 12.32 ± 2.87 days, respectively. While those parameters in the C‐TLIF group was 862.70 ± 300.24 ml, 141.35 ± 31.72 min and 15.51 ± 2.08 days, respectively. Average operation time and hospital stay time were significantly shorter, and blood loss was significantly less in the W‐TLIF group than in the C‐TLIF group (P < 0.05). VAS and ODI in the W‐TLIF group were significantly less than those in the C‐TLIF group at 1 week after operation and final follow‐up. The kyphotic angle and vertebral body height were improved. There was 1–2 grade improvement in patients with neurological deficit. Thirty‐three patients in the W‐TLIF group and 32 patients in the C‐TLIF group had achieved fusion during follow‐up. No internal fixation failure was observed in two groups.ConclusionsThe both techniques of W‐TLIF and C‐TLIF were feasible and effective for unstable thoracolumbar fracture with TIDL. Compare to C‐TLIF, The technique of W‐TLIF was a relatively less invasive way to decompress the neural elements and an easy method to reconstruct the anterior column using the same posterior approach.  相似文献   
955.
分析系统功能需求及云服务技术优势,从功能架构、网络接入方式、网络安全管理几方面阐述基于云服务的影像传输与远程会诊系统设计,介绍系统实际应用情况,指出该系统有助于充分发挥医联体内核心医院优势,提高联盟医院医学影像诊断水平。  相似文献   
956.
从架构、服务内容等方面阐述安徽省影像云远程医疗平台信息化建设,介绍平台应用情况,指出该平台能够实现全省所有影像数据互联互通、报告互认,有助于提升医学影像综合服务能力。  相似文献   
957.
Our work investigates the polycrystalline composite deformation behavior through multiscale simulations with experimental data at hand. Since deformation mechanisms on the micro-level link the ones on the macro-level and the nanoscale, it is preferable to perform micromechanical finite element simulations based on real microstructures. The image segmentation is a necessary step for the meshing. Our 2D EBSD images contain at least a few hundred grains. Machine learning (ML) was adopted to automatically identify subregions, i.e., individual grains, to improve local feature extraction efficiency and accuracy. Denoising in preprocessing and postprocessing before and after ML, respectively, is beneficial in high quality feature identification. The ML algorithms used were self-developed with the usage of inherent code packages (Python). The performances of the three supervised ML models—decision tree, random forest, and support vector machine—are compared herein; the latter two achieved accuracies of up to 99.8%. Calculations took about 0.5 h from the original input dataset (EBSD image) to the final output (segmented image) running on a personal computer (CPU: 3.6 GHz). For a realizable manual pixel sortation, the original image was firstly scaled from the initial resolution 10802 pixels down to 3002. After ML, some manual work was necessary due to the remaining noises to achieve the final image status ready for meshing. The ML process, including this manual work time, improved efficiency by a factor of about 24 compared to a purely manual process. Simultaneously, ML minimized the geometrical deviation between the identified and original features, since it used the original resolution. For serial work, the time efficiency would be enhanced multiplicatively.  相似文献   
958.
Aluminum (Al) and its alloys are the second most used materials spanning industrial applications in automotive, aircraft and aerospace industries. To comply with the industrial demand for high-performance aluminum alloys with superb mechanical properties, one promising approach is reinforcement with ceramic particulates. Laser powder-bed fusion (LPBF) of Al alloy powders provides vast freedom in design and allows fabrication of aluminum matrix composites with significant grain refinement and textureless microstructure. This review paper evaluates the trends in in situ and ex situ reinforcement of aluminum alloys by ceramic particulates, while analyzing their effect on the material properties and process parameters. The current research efforts are mainly directed toward additives for grain refinement to improve the mechanical performance of the printed parts. Reinforcing additives has been demonstrated as a promising perspective for the industrialization of Al-based composites produced via laser powder-bed fusion technique. In this review, attention is mainly paid to borides (TiB2, LaB6, CaB6), carbides (TiC, SiC), nitrides (TiN, Si3N4, BN, AlN), hybrid additives and their effect on the densification, grain refinement and mechanical behavior of the LPBF-produced composites.  相似文献   
959.
目的:系统评价重组结核杆菌融合蛋白(EC)相较于结核菌素纯蛋白衍生物(TB-PPD)用于诊断结核分枝杆菌(Mycobacterium tuberculosis,MTB)感染的有效性和安全性。方法:检索临床指南数据库、生物医学文献数据库、卫生行政部门和行业协会官方网站及不良反应监测官方网站,检索时间均自建库截止到2022年2月。英文检索词:Recombinant Mycobacterium tuberculosis fusion protein、CFP10/ESAT6;中文检索词:重组结核分枝杆菌融合蛋白、重组结核杆菌融合蛋白、宜卡、CFP10/ESAT6。收集重组结核杆菌融合蛋白(EC)和结核菌素纯蛋白衍生物(TB-PPD)诊断MTB感染有效性和安全性的指南、共识、团体标准、系统评价和原始研究等。由2名研究者独立筛选文献、提取资料并评价纳入研究的偏倚风险,根据异质性大小采用Meta分析或描述性分析。结果:纳入指南2部、专家共识3篇、团体标准2部,均指出重组结核杆菌融合蛋白(EC)和结核菌素纯蛋白衍生物(TB-PPD)可用于诊断MTB感染和结核病辅助诊断。纳入系统评价1篇,结果显示,重组...  相似文献   
960.
(1) Background: Haloarchaea comprise extremely halophilic organisms of the Archaea domain. They are single-cell organisms with distinctive membrane lipids and a protein-based cell wall or surface layer (S-layer) formed by a glycoprotein array. Pleolipoviruses, which infect haloarchaeal cells, have an envelope analogous to eukaryotic enveloped viruses. One such member, Halorubrum pleomorphic virus 6 (HRPV-6), has been shown to enter host cells through virus-cell membrane fusion. The HRPV-6 fusion activity was attributed to its VP4-like spike protein, but the physiological trigger required to induce membrane fusion remains yet unknown. (2) Methods: We used SDS-PAGE mass spectroscopy to characterize the S-layer extract, established a proteoliposome system, and used R18-fluorescence dequenching to measure membrane fusion. (3) Results: We show that the S-layer extraction by Mg2+ chelating from the HRPV-6 host, Halorubrum sp. SS7-4, abrogates HRPV-6 membrane fusion. When we in turn reconstituted the S-layer extract from Hrr. sp. SS7-4 onto liposomes in the presence of Mg2+, HRPV-6 membrane fusion with the proteoliposomes could be readily observed. This was not the case with liposomes alone or with proteoliposomes carrying the S-layer extract from other haloarchaea, such as Haloferax volcanii. (4) Conclusions: The S-layer extract from the host, Hrr. sp. SS7-4, corresponds to the physiological fusion trigger of HRPV-6.  相似文献   
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