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101.
The oral retention of fluoride (F) following the topical application of a newly developed APF foam was compared with a conventional APF gel. Twenty adults aged 16-26 years participated in the study. Ten of the subjects received the F foam and gel treatments, on separate occasions, with a saliva ejector while another 10 subjects received the same treatment without saliva ejector. Approximately 4 g of the gel, and 0.9 g foam, were dispensed for each treatment. The amounts of fluoride applied, recovered from the mouths, and retained in the mouth were calculated for each treatment. 相似文献
102.
目的:建立下颌前牙不同程度牙槽骨吸收后的釉质、牙本质、牙骨质、牙周膜、松质骨、皮质骨等组织的三维有限元模型。方法:利用薄层CT扫描技术与Ansys软件相结合,对层厚为1mm的CT断层影像进行分析处理。结果:模型具有良好的几何相似性,共有单元约13万个,节点约19万个,数据量约130MB,可以根据要求任意旋转、缩放、透视、剖开,进行多种方式观察;并可以按照不同研究目的和要求,对模型进行简单的修改和调整,模拟牙槽骨吸收、联冠修复等临床治疗所需的几何形态,考查各种约束和加载条件下前牙的力学反应;讨论了约束的处理和载荷的施加方式。结论:薄层CT扫描技术与Ansys软件相结合建立的三维有限元模型,能较精确地模拟实际情况,为进一步研究下颌前牙牙槽骨吸收和联冠修复奠定了良好的基础。 相似文献
103.
目的 探讨TMD患者关节液中5 -HT和NPY的水平与关节源性疼痛的关系。方法 用ELISA法检测TMD患者的1 2 6侧关节和健康志愿者的32侧关节的关节液标本中的5 -HT ,用放射免疫测定法检测关节液标本中NPY的含量。1 2 6侧TMD患者的关节液标本分为疼痛组(n =90 )和无痛组(n =36 ) ;32名正常志愿者的32侧关节液设为对照组(n =32 )。结果 所有标本都检出5 -HT ,无痛组含量为1 78.75 0±6 4 .979ng/ml,疼痛组含量为2 2 3.5 2 2±82 .6 36ng/ml,对照组含量为1 36 .1 2 5±5 5 .0 75ng/ml。统计学检验:疼痛组与无痛组、疼痛组与对照组以及无痛组与对照组间比较均有显著性差异(P <0 .0 5 )。NPY检测结果:疼痛组1 33.5 0 0±4 6 .6 6 4 pg/ml,无痛组99.6 5 6±2 5 .873pg/ml,对照组83.2 86±2 8.397pg/ml。统计学检验:疼痛组与无痛组、疼痛组与对照组以及无痛组与对照组间比较均有显著性差异(P <0 .0 5 )。结论 关节液中5 -HT、NPY的水平,患者组显著高于正常人组,并且在患者中疼痛组又显著高于无痛组,表明患者关节内存在炎症状态,也表明关节疼痛与关节液中5 -HT、NPY的水平增高密切相关。 相似文献
104.
Risk factors for dental implant failure: a strategy for the analysis of clustered failure-time observations 总被引:4,自引:0,他引:4
This study's objective was to identify, in a statistically valid and efficient manner, the risk factors associated with dental implant failure. We hypothesize that factors exist which can be modified by clinicians to enhance outcome. A retrospective cohort study design was used. Cohort members had >or= one implant placed. Risk factors were classified as demographic, health status, implant-, anatomic-, or prosthetic-specific, and reconstructive variables. The outcome variable was implant failure. The cohort was composed of 677 patients who had 2349 implants placed. Based on the adjusted multivariate model, factors associated with implant failure were tobacco use, implant length, staging, well size, and immediate implants (p 相似文献
105.
Orthodontists from different backgrounds may have different opinions about removable and fixed orthodontic appliances, but there have been few objective comparisons of their relative treatment effectiveness. It is the purpose of the present study to analyze objectively the effectiveness of these two types of appliances. Eighty cases involving patients who had been treated with removable appliances and 67 cases of patients treated with fixed appliances were studied with respect to the Occlusal Index (OI). Scores indicating severity of malocclusion were obtained from pretreatment and posttreatment study casts. The effectiveness of the fixed appliance (represented by average reduction in OI score) was much greater than that of the removable appliance. The result of treatment with the fixed appliance was also found to be much better than that of the treatment with the removable appliance (indicated by the much lower posttreatment OI score in the fixed-appliance cases). The Occlusal Index was designed to measure features of basic malocclusion and is not a very sensitive index for assessing symptoms of a developing malocclusion. The fact that both the treatment effectiveness and the treatment results of the removable appliance were found to be inferior to those of the fixed appliance may indicate that the removable appliance has been used largely to correct "symptoms" rather than basic malocclusion. 相似文献
106.
Fascin在口腔鳞癌中的表达及临床意义 总被引:2,自引:0,他引:2
目的:研究Fascin在口腔鳞癌患者中的表达,以期为口腔鳞癌找到一个肿瘤标志物和靶向治疗的新靶标。方法:使用免疫组化Max Vision两步法观察Fascin在56例口腔鳞癌患者和12例口腔黏膜良性病变中的表达。结果:Fascin在口腔鳞癌中高表达(P=0.003)。Fascin的表达和肿瘤的临床分期(P=0.006),组织学分级(P=0.024),淋巴结转移(P=0.021)有关,与患者的性别(P=0.514)和年龄(P=0.474)无关。Fascin的染色强度与临床分期(P=0.041)和淋巴结转移(P=0.044)有关。Fascin高表达与低表达患者的生存率间有显著差异(P=0.030)。结论:Fascin可以作为口腔鳞癌有参考意义的肿瘤标志物,且可能和患者的不良预后有关,有望成为口腔鳞癌治疗的新靶标。 相似文献
107.
由于刊名缩写简明,达意,节省籍幅,故而在国内外口腔医学及相关学科专业期刊参考文献中广泛采纳。通常在临床,教学及科研中,因某种目的常需从一篇原始文章或综述的参考文献中查找引用文献,无疑需要具备辨认参考文献中的刊名缩写,理解其全意的能力, 相似文献
108.
目的:讨论眶-上颌骨-颧骨(orbital maxillary zygoma,OMZ)复合骨折的特点,以及治疗方法的选择,总结影响OMZ骨折疗效的因素。方法:对华西口腔医院1989年以来收治的128例OMZ骨折进行临床回顾性研究。结果:128例眶-上颌骨-颧骨复合性骨折中,25.8%伴有眶部并发症,对症处理后症状大多消失,8例复视患者眶底或眶周行自体骨整复或Medicon种植体整复,症状消失。83例采用微型夹板坚强内固定,其中4例采用可吸收小夹板。11例陈旧性骨折采用正颌外科技术恢复其面形及咬功能。结论:OMZ骨折应早期复位、坚强内固定,恰当的软组织处理等是影响治疗效果的主要因素。 相似文献
109.
Levels of soluble cytokine factors in temporomandibular joint effusions seen on magnetic resonance images 总被引:1,自引:0,他引:1
Kaneyama K Segami N Sun W Sato J Fujimura K 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,99(4):411-418
OBJECTIVE: To elucidate the correlations between joint effusion (JE) on T2-weighted magnetic resonance images (MRI) of the temporomandibular joint (TMJ) and the levels of various cytokine receptors, cytokine antagonists, and protein in the synovial fluid of patients with temporomandibular joint disorders (TMD). STUDY DESIGN: Fifty-five TMJs of 55 patients with TMD were scanned by MRI, and synovial fluid samples were obtained on the same day. The grade of JE was evaluated on a scale of 0 to 3: Grades 0 and 1 indicated absence, and grades 2 and 3 indicated the presence of JE. Correlations were evaluated between JE and the concentrations of soluble tumor necrosis factor receptors I and II (sTNFR-I and sTNFR-II, respectively), IL-6 soluble receptor (IL-6sR), IL-1 soluble receptor type II, and IL-1 receptor antagonist and protein in the synovial fluid of patients with TMD. RESULTS: The concentrations of sTNFR-I and protein in the group with JE (18 joints) were significantly higher than in the group without JE (37 joints). In addition, there were significant positive correlations between the grade of JE and the levels of sTNFR-I, sTNFR-II, and protein. CONCLUSIONS: sTNFRs and protein may play important roles in the pathogenesis of TMD. These mediators seem to influence the expression of JE, which may reflect synovial inflammation of the TMJ. 相似文献
110.