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21.
张磊  陈娜  王颖  翦凡  张在强  潘华 《武警医学》2021,32(12):1030-1032
 目的 探讨髂腰肌肌电图在诊断多发性肌炎中的应用价值。方法 回顾性收集2018-01至2019-02于首都医科大学附属北京天坛医院就诊并确诊为多发性肌炎的28例患者(多发性肌炎组)的临床资料,以及年龄、性别相匹配的健康人20名(对照组),就其髂腰肌、股四头肌、三角肌肌电图自发电位和小力收缩运动单位电位(motor unit action potential, MUAP)进行分析。结果 对照组髂腰肌未检测出自发电位,多发性肌炎组髂腰肌自发电位阳性率为57.14%(16/28),显著高于对照组(P<0.001);另外其MUAP波幅显著低于对照组[(424.20±82.41)μV vs. (593.93±65.49 )μV,P<0.001],MUAP时限也显著短于对照组[(9.73±2.05)vs. (11.26±0.42) ms,P<0.01]。在肌肉病患者中,股四头肌自发电位阳性率为35.71%(10/28),三角肌自发电位阳性率为25.00%(7/28),三角肌自发电位显著低于髂腰肌(P<0.05)。结论 髂腰肌在多发性肌炎患者中有明显的肌源性损害的表现,可为临床提供更加敏感、客观的诊断依据。  相似文献   
22.
目的探讨三叉神经鞘瘤的临床分型及其手术疗效。方法回顾性分析2017年1月至2019年11月首都医科大学附属北京天坛医院神经外科手术治疗的51例(包括少见部位和肿瘤最大径≥6 cm的患者)三叉神经鞘瘤患者的临床资料。根据Yoshida和Kawase的MPE分型分别采用颞下经岩前入路(30例)、经额颞断颧弓入路(12例)、经额眶颧人路(4例)、经枕下乙状窦后入路(2例)、经乙状窦前入路(2例)和经远外侧入路(1例)。术后随访MRI、新发症状及脑神经功能的恢复情况。结果51例患者中,肿瘤全切除46例(90.2%),近全切除4例,大部切除1例,无手术死亡病例。其中6例中线-鞍上扩展亚型的患者,肿瘤全切除2例,近全切除3例,大部切除1例。7例肿瘤直径≥6 cm的患者中,肿瘤全切除6例,肿瘤卒中1例;其中4例行游离脂肪填塞结合颅底硬膜缝合的颅底重建。51例患者的随访时间为(20.2±2.7)个月(3~38个月)。24例术前面部麻木的患者中,12例(50.0%)随访期间仍存在重度三叉神经麻搏表现。51例患者中,有13例(25.5%)术后新发三叉神经功能异常的患者中,7例随访期间遗留轻度三叉神经麻搏症状。其余脑神经症状较术前有所恢复,并且术后新发神经功能障碍者大多恢复正常。6例中线-鞍上扩展亚型的患者术后神经功能恢复较差。结论三叉神经鞘瘤在MPE分型的基础上可增加中线-鞍上扩展亚型,该亚型相对少见,但其临床表现具有特征性,手术全切除困难。手术对于改善三叉神经鞘瘤面部麻木作用有限,术前伴有面部麻木者三叉神经功能预后较差。  相似文献   
23.
Yang  Yi  Liu  Qingyuan  Jiang  Pengjun  Yang  Junhua  Li  Maogui  Chen  Shanwen  Mo  Shaohua  Zhang  Yanan  Ma  Xuesheng  Cao  Yong  Cui  Deqi  Wu  Jun  Wang  Shuo 《Neurological sciences》2021,42(12):5007-5019
Objectives

The stability of intracranial aneurysms (IAs) may involve in multidimensional factors. Backpropagation (BP) neural network could be adopted to support clinical work. This preliminary study aimed to delve into the feasibility of BP neural network in assessing the risk of IA rupture/growth and to prove the advantage of multidimensional model over single/double-dimensional model.

Methods

Thirty-six IA patients were recruited from a prospective registration study (ChiCTR1900024547). All patients were followed up until aneurysm ruptured/grew or 36 months after being diagnosed with the IAs. The multidimensional data regarding clinical, morphological, and hemodynamic characteristics were acquired. Hemodynamic analyses were conducted with patient-specific models. Based on these characteristics, seven models were built with BP neural network (the ratio of training set to validation set as 8:1). The area under curves (AUC) was calculated for subsequent comparison.

Results

Forty-five characteristics were determined from 36 patients with 37 IAs. In the models based on the single dimension of IA characteristics, only morphological characteristics exhibited high performance in assessing 3-year IA stability (AUC = 0.703, P = 0.035). Among the models integrating two dimensions of IA characteristics, clinical-morphological (AUC = 0.731, P = 0.016), clinical-hemodynamic (AUC = 0.702, P = 0.036), and morphological-hemodynamic (AUC = 0.785, P = 0.003) models were capable of assessing the risk of 3-year IA rupture/growth. Moreover, the models including all three dimensions exhibited the maximum predicting significance (AUC = 0.811, P = 0.001).

Conclusion

The present preliminary study reported that BP neural network might support assessing the 3-year stability of IAs. Models based on multidimensional characteristics could improve the assessment accuracy for IA rupture/growth.

  相似文献   
24.
线粒体DNA损伤与细胞凋亡   总被引:1,自引:0,他引:1  
细胞核DNA(nuclear DNA,nDNA)损伤后诱导细胞凋亡的信号转导途径已经逐渐清晰,而线粒体DNA(mitochondrial DNA,mtDNA)损伤与细胞凋亡之间的关系尚有待进一步明确.目前已有研究结果表明:mtDNA断裂、缺失或功能缺陷能够显著影响细胞凋亡发生率;线粒体缺失细胞(p0细胞)同其亲代细胞相比,对多种凋亡诱导因素的反应存在显著差异;ROS的产生并非mtDNA损伤诱导凋亡的必要条件,mtDNA损伤断裂本身可能启动了凋亡的级联反应.但mtDNA的损伤,在细胞凋亡的信号转导途径具体扮演何种角色,还有待深入研究.  相似文献   
25.
目的 应用层次分析法(AHP)和德尔菲法建立医学图像存档与传输系统(PACS)评估指标体系。方法 回溯性检索2003年 ~ 2012年PubMed、Embase、Science Citation Index、Cochrane Library、万方数据、中国知网等6种电子数据库的PACS文献,在文献分析的基础上,邀请医学影像、计算机应用、生物医学工程、PACS项目管理、临床医疗等专业的9名专家咨询,采用德尔菲法建立评估体系的指标框架,采用AHP确定评估体系各级指标权重,并计算下级指标相对于上级指标的组合权重。结果 构建的评估体系包括一级指标5个、二级指标23个。5个一级指标供应商综合能力、产品成熟性与先进性、系统安全性与可靠性、系统准确性和系统性能的权重分别为0.091 7、0.224 7、0.232 6、0.181 0、0.270 0;各级指标权重均满足一致性检验,所得权重是可以接受的;二级指标组合权重按权重大小排序,权重最大的前5位分别是“工作站性能”、“系统存储与影像存档性能”、“影像质量及显示性能”、“数据的完整性”和“数据安全策略”。结论 德尔菲法和APH相结合是建立评估体系的有效方法,同时,这种构建评估体系的方法也为大型设备的招标评估指标的制定提供新思路。  相似文献   
26.
Objective This study aimed to assess the association of waist circumference(WC) with all-cause mortality among Chinese adults.Methods The baseline data were from Shanxi Province of 2002 China Nutrition and Health Survey. The death investigation and follow-up visit were conducted from December 2015 to March 2016. The visits covered up to 5,360 of 7,007 participants, representing a response rate of 76.5%. The Cox regression model and floating absolute risk were used to estimate hazard ratio and 95% floating CI of death by gender and age groups(≥ 60 and 60 years old). Sensitivity analysis was performed by excluding current smokers; participants with stroke, hypertension, and diabetes; participants who accidentally died; and participants who died during the first 2 years of follow-up.Results This study followed 67,129 person-years for 12.5 years on average, including 615 deaths. The mortality density was 916 per 100,000 person-years. Low WC was associated with all-cause mortality among men. Multifactor-adjusted hazard ratios(HR) were 1.60(1.35–1.90) for WC 75.0 cm and 1.40(1.11–1.76) for WC ranging from 75.0 cm to 79.9 cm. Low WC( 70.0 cm and 70.0–74.9 cm) and high WC(≥ 95.0 cm) groups had a high risk of mortality among women. The adjusted HRs of death were 1.43(1.11–1.83), 1.39(1.05–1.84), and 1.91(1.13–3.22).Conclusion WC was an important predictor of death independent of body mass index(BMI). WC should be used as a simple rapid screening and predictive indicator of the risk of death.  相似文献   
27.
目的 探讨急性ST段抬高型心肌梗死(ST-segment elevation myocardial infarction,STEMI)合并射血分数保留的心力衰竭(heart failure with preserved ejection fraction,HFpEF)患者行急诊经皮冠状动脉介入术(primary percutaneous coronary intervention,PPCI),术中发生无复流的影响因素.方法 连续选取2017年1月至2019年1月就诊于首都医科大学附属北京安贞医院急诊科并行急诊PCI治疗的STEMI合并HFpEF患者326例,按照急诊PCI术中血流情况,分为正常复流组(255例)和无复流组(71例).比较两组的临床资料,分析无复流发生的影响因素.结果 合并HFpEF的STEMI患者,PPCI术后无复流发生率为21.8%(71/326),两组之间急诊收缩压(SBP)[(113.75±23.27)mm Hg比(127.84±34.58)mm Hg,P=0.046]、即刻血糖水平[(14.32±6.75)mmol/L比(9.17±7.50)mmol/L,P=0.038]、发病到再灌注时间[(118.07±41.35)min比(9.74±39.23)min,P=0.037]、球囊扩张次数(12.5%比10.1%,P=0.042)差异均有统计学意义(P<0.05);经多因素Logistic回归分析显示,急诊SBP(OR=1.089,95%CI 0.746~18.247,P=0.031)、球囊扩张次数(OR=1.980,95%CI 0.883~1.087,P=0.039)、发病至再灌注时间(OR=2.985,95%CI 0.064~0.982,P=0.048)是急诊PCI术中无复流发生的危险因素.结论 合并EFpHF合并STEMI患者行PPCI后无复流发生与入院收缩压、球囊扩张次数、发病至再灌注时间具有相关性.  相似文献   
28.
目的通过对动脉瘤性蛛网膜下腔出血(aSAH)后早期血液凝血和纤溶相关标志物进行动态分析,探讨其与迟发性脑缺血(DCI)之间的关系,尝试从临床角度阐述微血栓形成机制在DCI发生发展中可能的潜在影响。方法前瞻性连续纳入2016年12月至2018年6月北京天坛医院发病3 d内的aSAH住院患者165例。入院后按照统一标准化方案分别采集患者入院时、发病后(4±1)、(7±1)、(10±1)、(13±1)d的血液样本,记录DCI患者及非DCI患者各时间点的部分血液凝血[包括凝血酶原时间(PT)、活化部分凝血活酶时间(APTT)、血小板计数、血管性血友病因子(vWF)抗原定量和vWF活性]及纤溶相关标志物参数(D-二聚体、纤维蛋白原)。PT、APTT、纤维蛋白原水平通过凝血酶测定,D-二聚体含量通过乳胶光度法测定,vWF抗原定量和vWF活性检测分别采用vWF抗原检测试剂盒和vWF活性检测试剂盒,并对两组间不同时间点各参数进行重复测量方差分析。结果DCI发生率为31.5%(52/165)。凝血及纤溶标志物相关结果显示,DCI患者在aSAH后早期即出现血管性血友病因子(vWF)抗原含量和活性升高,并在发病后(7±1)d达到高峰,DCI患者vWF抗原及活性水平较非DCI患者更高,两组间差异具有统计学意义(F值分别为6.873、5.784,P值分别为0.017、0.021),同时vWF抗原及活性水平与时间相关(F值分别为105.448、89.141,均P<0.01),且存在组别与采样时间之间的交互效应(F值分别为9.525、10.114,P值分别为0.022、0.016)。此外,DCI与不同采样时间对PT、APTT、血小板计数、D-二聚体、纤维蛋白原等水平无明显影响(均P>0.05),并且两组别与时间不存在交互作用(均P>0.05)。结论DCI患者vWF抗原含量及活性明显高于非DCI患者,提示可能存在微血栓形成,动态监测vWF抗原含量及活性有助于早期发现DCI。  相似文献   
29.
The miniature pig is an optimal animal model for studying nervous system disease because of its physiologic and pathologic features. However, the rete mirabile composed of arteries and veins at the skull base limits their application as a model of ischemic stroke by middle cerebral artery occlusion. The present study investigated the possibility of establishing an ischemic stroke model in the miniature pig by blocking the skull base retia with sodium alginate microspheres. Three Bama miniature pigs were used. Using the monitor of C-arm X-ray machine, sodium alginate microspheres (100-300 μm), a novel embolic material, were injected through the femoral artery, aortic arch, common carotid artery, ascending pharyngeal artery and the retia. Results were evaluated using carotid arteriography, MRI, behavior observation and histology. The unilateral rete mirabile was completely blocked, resulting in disturbance in blood supply to the basal ganglia, astasia of the right hind limb and salivation. MRI and hematoxylin-eosin staining showed an evident infarction focus in the basal ganglia. These findings indicate that sodium alginate microspheres are a suitable embolic material for blocking the skull base retia in miniature pigs to establish an ischemic stroke models.  相似文献   
30.
《Vaccine》2023,41(32):4679-4684
ObjectiveTo examine the seroprevalence of measles and varicella zoster virus (VZV) among healthcare workers (HCW) and evaluate the concordance between self-reported history of previous disease or vaccination and seropositivity.DesignA seroprevalence study and survey.SettingA university-affiliated tertiary care hospital.ParticipantsAll HCWs working in high-risk services in 2017 underwent serologic tests and survey; all new HCWs employed in the subsequent years, serologic tests only.MethodsA serologic study was conducted using chemiluminescence immunoassay (2017) or enzyme immunoassays (2018 and later). HCWs who underwent serological testing in 2017 completed a self-administered questionnaire on their history of infection and vaccination.ResultsA total of 10,278 and 9607 HCWs underwent serologic tests for measles and VZV IgG, respectively, from 2017 to 2022. The overall seropositivity rates for measles and VZV were 78.1 % and 92.8 %, respectively. Measles seropositivity declined gradually from >90 % in the HCWs born in the 1960s to <80 % in those born in the 1990s. There was a significant difference in measles seropositivity between the birth cohorts (BCs) 1967–1984 and 1985–1999 (P < 0.001; odds ratio, 1.16; 95 % confidence interval, 1.14–1.18). The seropositivity for VZV was stable, at >90 % in all BCs. The self-reported vaccination history was not independently associated with seropositivity, and the negative predictive value of the survey was very low (9.6 % and 13.1 %, respectively).ConclusionsMeasles seropositivity showed a substantial decline among HCWs born in 1985 or later, while varicella seropositivity remained high. The self-reported vaccination history was not sufficiently reliable for screening HCWs.  相似文献   
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