全文获取类型
收费全文 | 51933篇 |
免费 | 5025篇 |
国内免费 | 1172篇 |
专业分类
耳鼻咽喉 | 197篇 |
儿科学 | 681篇 |
妇产科学 | 379篇 |
基础医学 | 5483篇 |
口腔科学 | 880篇 |
临床医学 | 5273篇 |
内科学 | 7721篇 |
皮肤病学 | 289篇 |
神经病学 | 4379篇 |
特种医学 | 1620篇 |
外国民族医学 | 2篇 |
外科学 | 3701篇 |
综合类 | 5963篇 |
现状与发展 | 9篇 |
一般理论 | 1篇 |
预防医学 | 9758篇 |
眼科学 | 482篇 |
药学 | 5500篇 |
58篇 | |
中国医学 | 3609篇 |
肿瘤学 | 2145篇 |
出版年
2024年 | 251篇 |
2023年 | 1204篇 |
2022年 | 2003篇 |
2021年 | 3025篇 |
2020年 | 2920篇 |
2019年 | 2045篇 |
2018年 | 1797篇 |
2017年 | 1865篇 |
2016年 | 1817篇 |
2015年 | 1901篇 |
2014年 | 3838篇 |
2013年 | 3917篇 |
2012年 | 3251篇 |
2011年 | 3487篇 |
2010年 | 2742篇 |
2009年 | 2583篇 |
2008年 | 2600篇 |
2007年 | 2375篇 |
2006年 | 2086篇 |
2005年 | 1695篇 |
2004年 | 1397篇 |
2003年 | 1291篇 |
2002年 | 1045篇 |
2001年 | 831篇 |
2000年 | 668篇 |
1999年 | 578篇 |
1998年 | 492篇 |
1997年 | 476篇 |
1996年 | 392篇 |
1995年 | 390篇 |
1994年 | 305篇 |
1993年 | 284篇 |
1992年 | 241篇 |
1991年 | 207篇 |
1990年 | 226篇 |
1989年 | 193篇 |
1988年 | 196篇 |
1987年 | 164篇 |
1986年 | 170篇 |
1985年 | 211篇 |
1984年 | 170篇 |
1983年 | 121篇 |
1982年 | 132篇 |
1981年 | 115篇 |
1980年 | 108篇 |
1979年 | 64篇 |
1978年 | 57篇 |
1977年 | 41篇 |
1976年 | 59篇 |
1975年 | 29篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Cancer radiothérapie》2022,26(4):611-615
In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors. 相似文献
2.
Anne-Sophie Worm Fenger Markus Harboe Olsen Maria Louise Fabritius Christian Gunge Riberholt Kirsten Møller 《Acta anaesthesiologica Scandinavica》2023,67(2):240-247
Background
Hyperglycaemia is common in patients with acute brain injury admitted to an intensive care unit (ICU). Many studies have found associations between development of hyperglycaemia and increased mortality in hospitalised patients. However, the optimal target for blood glucose control is unknown. We want to conduct a systematic review with meta-analysis and trial sequential analysis to explore the beneficial and harmful effects of restrictive versus liberal glucose control on patient outcomes in adults with severe acute brain injury.Methods
We will systematically search medical databases including CENTRAL, Embase, MEDLINE and trial registries. We will search the following websites for ongoing or unpublished trials: http://www.controlled-trials.com/ , http://www.clinicaltrials.gov/ , www.eudraCT.com , http://centerwatch.com/ , The Cochrane Library's CENTRAL, PubMed, EMBASE, Science Citation Index Expanded and CINAHL. Two authors will independently review and select trials and extract data. We will include randomised trials comparing levels of glucose control in our analyses and observational studies will be included to address potential harms. The primary outcomes are defined as all-cause mortality, functional outcome and health-related quality of life. Secondary outcomes include serious adverse events including hypoglycaemia, length of ICU stay and duration of mechanical ventilation, and explorative outcomes including intracranial pressure and infection. Trial Sequential Analysis will be used to investigate the risk of type I error due to repetitive testing and to further explore imprecision. Quality of trials will be evaluated using the Cochrane Risk of Bias tool, and quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.Discussion
The results of the systematic review will be disseminated through peer-reviewed publication. With the review, we hope to inform future randomised clinical trials and improve clinical practice. 相似文献3.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。 相似文献
4.
《Gait & posture》2021
BackgroundRocker sole (RS) shoes have been linked to impaired postural control. However, which features of RS design affect balance is unclear.Research questionWhich RS design features affect standing balance and gait stability?MethodsThis study utilized an intervention and cross-over design. Twenty healthy young adults (10 males and 10 females) participated in this study. Standing balance and gait stability were measured using a single force platform and three-dimensional motion analysis system, respectively. The experimental conditions included the control shoe and five RS shoes in the combination of apex position (%) and apex angle (degree) for RS50-95, RS60-95, RS70-95, RS60-70, and RS60-110. The main outcome measures were the area surrounding the maximal rectangular amplitude, mean path length, average displacement of the center of pressure along the lateral and anterior/posterior directions, and maximal center of pressure excursion as the standing balance and lateral margin of stability as the gait stability. Statistical analyses were conducted using a two-way split-plot analysis of variance with repeated measures (with RS design as the within-subject factor and sex as the between-subject factor) and the Bonferroni post hoc test (α = .05).ResultsRegarding the mean path length, RS60-70 was significantly longer than the control shoe, and it showed a significantly increased lateral margin of stability. Thus, RS60-70 was shown to affect standing balance, limit of stability, and gait stability of the frontal plane during gait.SignificanceThese results suggest that the apex angle of the RS design feature affects standing balance and gait stability, and RS60-70 is detrimental to stability. Therefore, when RS with a small apex angle is prescribed, it is necessary to consider the patient’s balance ability. 相似文献
5.
目的:探索以系统化、标准化的新型冠状病毒核酸检测为核心和重要组成部分,建立适合于眼科医院新冠疫情精准防控切实可行的防控体系。方法:系列病例研究。自2020年2月24日至3月2日期间,以标准化病毒核酸检测联合血常规、C反应蛋白(CRP)、血清淀粉样蛋白A(SAA)等检测作为所有眼科手术患者术前筛查常规检测项目,同时也为返岗员工提供病毒核酸检测。设计调查问卷了解受检者对鼻咽拭子采样的接受度以及核酸检测结果对其心理状态的影响。结果:99例患者血液学检测结果有一定的异常比例,其中SAA检测结果增高13例,淋巴细胞计数减低12例、增高5例,白细胞计数增高11例、减低1例,CRP增高2例,新型冠状病毒核酸检测均阴性。33例本院职工新型冠状病毒核酸检测均阴性。12%的受访者对鼻咽拭子采样接受度评分较低。受检者在核酸检测前后思想压力评分较高的比例分别为46.7%和6.7%。结论:该项举措一方面为术前新冠病毒肺炎筛查及鉴别诊断提供了客观依据,很大程度上排除了隐性无症状感染者传播的可能,有利于减少二次传播的风险,降低院内交叉感染的概率;另一方面,核酸检测阴性结果有利于调整患者术前的心理状态并缓解医护人员在疫情防控期间的心理压力。 相似文献
6.
Julie Despres Yasmina Ramdani Marine di Giovanni Magalie Bnard Abderrakib Zahid Mait Montero‐Hadjadje Florent Yvergnaux Thibaut Saguet Azeddine Driouich Marie‐Laure Follet‐Gueye 《Experimental dermatology》2019,28(8):922-932
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing. 相似文献
7.
正目前,临床上对于直肠癌常用的影像评估方法有MRI、螺旋CT、PET-CT、直肠腔内超声(ERUS)等。而MRI作为首选检查方式,对肿瘤位置、浸润深度、淋巴结转移、血管侵犯、环周切缘及周围器官侵犯等方面的评估均具有明显优势~([1-2])。通过MRI诊断淋巴结的方法通常是影像科医师逐层浏览每一幅图像,从中识别淋巴结的形状、界限及密度来判断,这种传统方式耗时较长且存在主观偏倚,导致 相似文献
8.
目的探讨品管圈在植入式静脉输液港(IVAP)患者护理中的应用。方法选取本院2018年10月-2018年12月IVAP患者30例作为对照组,2019年1月-2019年3月品管圈活动干预后IVAP患者30例作为观察组。对照组采用常规护理措施,观察组采用品管圈活动干预后的护理措施。比较两组IVAP患者并发症的发生率和对护理工作的满意度。结果观察组导管堵塞1例;并发症发生率为3.33%(1/30)。对照组感染4例,血栓2例,导管堵塞4例;并发症发生率为33.33%(10/30)。观察组并发症发生率低于对照组(P <0.05)。观察组对优质服务、技术水平、关怀、出院指导、护理总满意度评分分别为(42.39±5.27)分、(31.49±4.32)分、(22.25±4.69)分、(20.26±4.91)分、(112.24±10.38)分;对照组分别为(38.65±4.91)分、(28.68±4.26)分、(19.96±4.30)分、(19.94±4.63)分、(103.37±10.12)分;观察组对优质服务、技术水平、关怀、出院指导、护理总满意度评分均高于对照组(P <0.05)。结论通过品管圈活动干预后的护理措施明显降低IVAP患者并发症的发生率,提高患者对护理工作的满意度。 相似文献
9.
10.
《Journal of pharmaceutical sciences》2019,108(11):3515-3520
Particle size analysis in the pharmaceutical industry has long been a source of debate regarding how best to define measurement accuracy; the degree to which the result of a measurement or calculation conforms to the true value. Defining a “true” value for the size of a particle can be challenging as the output of its measurement will differ because of variations in measurement approaches, instrumental differences and calculation methods. Consequently, for “real” particles, a universal “true” value does not exist and accuracy is therefore not a definable characteristic. Accordingly, precision is then a measure of the ability to reproducibly achieve a measurement of unknown relevance.This article proposes, in place of accuracy, a means to define the “appropriateness” of a measurement in line with the critical quality attributes (CQA) of the material being characterized. The decision as to whether the measurement is correct should involve a link to the CQA; that is, correlation should be demonstrated, without which the measured particle size cannot be defined as a critical material attribute.Correspondingly, methods should also be able to provide sufficient precision to demonstrate discrimination relating to variation in the CQA. The benefits and challenges of this approach are discussed. 相似文献