全文获取类型
收费全文 | 3986篇 |
免费 | 288篇 |
国内免费 | 83篇 |
专业分类
耳鼻咽喉 | 34篇 |
儿科学 | 72篇 |
妇产科学 | 19篇 |
基础医学 | 856篇 |
口腔科学 | 35篇 |
临床医学 | 159篇 |
内科学 | 219篇 |
皮肤病学 | 6篇 |
神经病学 | 906篇 |
特种医学 | 65篇 |
外科学 | 389篇 |
综合类 | 304篇 |
预防医学 | 315篇 |
眼科学 | 191篇 |
药学 | 367篇 |
1篇 | |
中国医学 | 128篇 |
肿瘤学 | 291篇 |
出版年
2023年 | 60篇 |
2022年 | 85篇 |
2021年 | 126篇 |
2020年 | 124篇 |
2019年 | 120篇 |
2018年 | 107篇 |
2017年 | 120篇 |
2016年 | 124篇 |
2015年 | 130篇 |
2014年 | 194篇 |
2013年 | 225篇 |
2012年 | 224篇 |
2011年 | 242篇 |
2010年 | 193篇 |
2009年 | 209篇 |
2008年 | 208篇 |
2007年 | 190篇 |
2006年 | 175篇 |
2005年 | 146篇 |
2004年 | 133篇 |
2003年 | 117篇 |
2002年 | 84篇 |
2001年 | 79篇 |
2000年 | 69篇 |
1999年 | 47篇 |
1998年 | 34篇 |
1997年 | 38篇 |
1996年 | 39篇 |
1995年 | 38篇 |
1994年 | 32篇 |
1993年 | 32篇 |
1992年 | 26篇 |
1991年 | 28篇 |
1990年 | 23篇 |
1989年 | 19篇 |
1988年 | 17篇 |
1987年 | 19篇 |
1986年 | 28篇 |
1985年 | 53篇 |
1984年 | 37篇 |
1983年 | 42篇 |
1982年 | 45篇 |
1981年 | 41篇 |
1980年 | 42篇 |
1979年 | 36篇 |
1978年 | 35篇 |
1977年 | 18篇 |
1976年 | 26篇 |
1975年 | 18篇 |
1974年 | 14篇 |
排序方式: 共有4357条查询结果,搜索用时 15 毫秒
1.
《Journal of pediatric surgery》2023,58(9):1783-1788
BackgroundRecent studies have described the use of telehealth for pediatric surgical care during the COVID-19 pandemic. We aimed to evaluate equity in telehealth use by comparing rates of utilization and satisfaction with pediatric surgical telemedicine among Hispanic patients.MethodsWe conducted a retrospective cohort study of patients seen by a surgical subspecialty provider in the outpatient setting at a quaternary pediatric hospital between April 1 and June 30, 2020. Patients evaluated in the same three-month period in 2019 were analyzed as a historic control. Differences in Family Experience Survey (FES) responses based on race and ethnicity and preferred language of care were assessed using univariable and multivariable generalized linear modeling.ResultsThe pandemic cohort included fewer patients of Hispanic ethnicity and fewer Spanish-speakers. After controlling for visit type, comparison of Spanish-speaking and English-speaking patients revealed that Spanish-speaking families had significantly lower scores for FES items that evaluated healthcare provider explaining (IRR 0.74, 95% CI: 0.61–0.90), listening (IRR 0.76, 95% CI: 0.63–0.92), and time spent with the family (IRR 0.73, 95% CI: 0.60–0.89). There were no differences in FES responses based on insurance status or degree of medical complexity.ConclusionsTelehealth services were less commonly used among Hispanic and Spanish-speaking patients. Language may differentially affect family satisfaction with healthcare and telehealth solutions. Strategies to mitigate these inequities are needed and may include strengthening interpreter services and providing language-concordant care.Level of evidenceLevel IV. 相似文献
2.
Lina Jansen Lars Schwettmann Christian Behr Andrea Eberle Bernd Holleczek Christina Justenhoven Hiltraud Kajüter Kirsi Manz Frederik Peters Ron Pritzkuleit Andrea Schmidt-Pokrzywniak Eunice Sirri Fabian Tetzlaff Sven Voigtländer Volker Arndt 《International journal of cancer. Journal international du cancer》2023,153(10):1784-1796
Age-standardized cancer incidence has decreased over the last years for many cancer sites in developed countries. Whether these trends led to narrowing or widening socioeconomic inequalities in cancer incidence is unknown. Using cancer registry data covering 48 million inhabitants in Germany, the ecological association between age-standardized total and site specific (colorectal, lung, prostate and breast) cancer incidence in 2007 to 2018 and a deprivation index on district level (aggregated to quintiles) was investigated. Incidence in the most and least deprived districts were compared using Poisson models. Average annual percentage changes (AAPCs) and differences in AAPCs between deprivation quintiles were assessed using Joinpoint regression analyses. Age-standardized incidence decreased strongly between 2007 and 2018 for total cancer and all cancer sites (except female lung cancer), irrespective of the level of deprivation. However, differences in the magnitude of trends across deprivation quintiles resulted in increasing inequalities over time for total cancer, colorectal and lung cancer. For total cancer, the incidence rate ratio between the most and least deprived quintile increased from 1.07 (95% confidence interval: 1.01-1.12) to 1.23 (1.12-1.32) in men and from 1.07 (1.01-1.13) to 1.20 (1.14-1.26) in women. Largest inequalities were observed for lung cancer with 82% (men) and 88% (women) higher incidence in the most vs the least deprived regions in 2018. The observed increase in inequalities in cancer incidence is in alignment with trends in inequalities in risk factor prevalence and partly utilization of screening. Intervention programs targeted at socioeconomically deprived and urban regions are highly needed. 相似文献
3.
目的 探讨有氧运动对睡眠剥夺大鼠定位巡航活动和空间探索活动,海马区神经元形态,海马神经元树突棘密度、突触相关蛋白,以及海马区环磷酸腺苷反应元件结合蛋白(CREB)/脑源性神经营养因子(BDNF)信号通路的影响。 相似文献
4.
《Health & place》2022
This study aimed to understand the perceived effects of the COVID-19 pandemic on physical activity, recreation walking, and use of recreational facilities; and if the COVID-19 pandemic amplified disparities in physical activity, recreational walking, and use of recreational facilities related to the levels of neighborhood disadvantage. Recreational walking and the use of neighborhood streets and green spaces significantly decreased in high deprivation areas but not in low deprivation areas during the pandemic. While COVID-19 has negatively affected overall recreational activities, the inequitable impact on recreational walking and use of outdoor recreational facilities has been more evident in disadvantaged neighborhoods with greater deprivation. 相似文献
5.
《Clinical genitourinary cancer》2022,20(6):594-602
The management of patients with metastatic hormone-sensitive prostate cancer (mHSPC) has been significantly modified by the availability of innovative but expensive treatments, increasing the economic burden of prostate cancer. Here, we aimed to systematically identify and review published economic evaluations (EEs) related to the treatment of mHSPC and assess their quality. A systematic search was performed of the PubMed and Cochrane databases. Three reviewers independently selected EEs by defined inclusion and exclusion criteria. They extracted all data from each EE (general information, study population, data about the EE, interventions and comparators, and outcomes). They also assessed the quality of the selected EEs according to Drummond's checklist. Fourteen EEs published between 2016 and 2021 were eligible for the systematic review. The EEs found ADT + docetaxel to be the most cost-effective of all available treatments as a first-line strategy for mHSPC (abiraterone acetate plus prednisone, enzalutamide, and apalutamide). Five EEs showed that a simple price reduction of abiraterone acetate of 50% to 75% could change the results to render this treatment also cost-effective relative to that with docetaxel. Twelve EEs were of high quality, with a Drummond score ≥ 7. Analysis of the 14 EEs identified by our systematic review, amongst which 78.6% met high quality standards, showed that ADT + docetaxel tends to be the most cost-effective alternative for mHSPC. These results were assessed by sensitivity analysis. The data provided by this systematic review help to provide a better understanding of these treatments and the better use of healthcare resources. 相似文献
6.
目的用大鼠心肌细胞氧糖剥夺(oxygen glucose deprivation,OGD)/复灌(rexyenation,R)模型模拟大鼠心肌缺血-再灌注损伤(myocardial ischemia-reperfusion injury,MIRI),研究铁死亡(Ferroptosis)及其在大鼠MIRI中的作用。方法采用体外培养的大鼠H9c2心肌细胞,分为正常培养组(Control组)、铁死亡激动剂组(Erastin组)、氧糖剥夺/复灌组(OGD/R组)、溶剂对照组(OGD/R+DMSO组)和Ferroptosis抑制剂组(OGD/R+Fer-1组)。分别采用光学显微镜观察各实验组的细胞数目,CCK-8法检测不同实验组细胞活力,透射电子显微镜(TEM)观察不同实验组H9c2细胞超微结构的变化。结果光学显微镜观察到使用Ferroptosis抑制剂(Fer-1,0.5μmol/L)后,细胞死亡减少;CCK-8结果显示,Ferroptosis特异性抑制剂Fer-1可部分减轻复灌后引起的细胞生长抑制(P<0.001);电镜结果显示,OGD/R后H9c2细胞出现Ferroptosis特异性超微形态改变:脂质沉积增多,线粒体明显皱缩及双层脂质膜密度增加。结论大鼠H9c2心肌细胞OGD/R后存在Ferroptosis,Ferroptosis能够降低细胞活力导致细胞死亡。 相似文献
7.
背景与目的:雄激素剥夺治疗(androgen deprivation therapy,ADT)是前列腺癌患者常用的治疗方法之一,然而对于ADT后病灶的变化,目前仍缺乏直接、精准的评估方法。以术后病理学检查结果作为金标准,初步探讨多参数磁共振成像(multiparametric magnetic resonance imaging,mpMRI)联合 99mTc标记前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)小分子抑制剂(HYNIC-Glu-Urea-A,简称 99mTc-PSMA)单光子发射计算机体层成像(single photon emission computed tomography,SPECT)/计算机体层成像(computed tomography,CT)评估前列腺癌新辅助ADT后的疗效,即检测显著残留病灶的价值。 方法 回顾并分析2017年3月—2021年7月复旦大学附属肿瘤医院收治的154例接受新辅助ADT后行根治性前列腺切除术的前列腺癌患者的临床资料。所有患者均在术前行mpMRI及 99mTc-PSMA SPECT/CT检查,根据术后病理学检查结果分为显著残留组及完全缓解/微残留两组。比较两组的临床病理学特征、mpMRI前列腺局部复发磁共振成像报告评分(Prostate Magnetic Resonance Imaging for Local Recurrence Reporting,PI-RR)分数及 99mTc-PSMA SPECT/CT阳性率。采用受试者工作特征(receiver operating characteristic,ROC)曲线及曲线下面积(area under curve,AUC)分析mpMRI、 99mTc-PSMA SPECT/CT单独使用及联合使用时的诊断效能差异。 结果 术后病理学检查结果证实显著残留组128例、完全缓解/微残留组26例。患者平均年龄为(66.88±7.79)岁,中位年龄68岁,年龄47~85岁。两组患者年龄、初始PSA、Gleason评分差异无统计学意义(P>0.05);而新辅助ADT后PSA显著残留组明显高于完全缓解/微残留组,差异有统计学意义(P<0.05)。mpMRI诊断显著残留的AUC值为0.713,以PI-RR评分3为界值时灵敏度为78.13%,特异度为30.77%;以PI-RR评分4为界值时灵敏度为68.75%,特异度为69.23%。 99mTc-PSMA SPECT/CT诊断显著残留的AUC值为0.729,与mpMRI相比差异无统计学意义(P>0.05),灵敏度为76.56%,特异度为69.23%。mpMRI联合 99mTc-PSMA SPECT/CT使用时AUC为0.809,显著高于两者单独使用时(P<0.05)。 结论 mpMRI与 99mTc-PSMA SPECT/CT均可用于诊断前列腺癌新辅助ADT后显著残留灶,两者联合运用时可以显著提高诊断效能。 相似文献
8.
目的:探讨脑出血对酵母沉默信息调节因子2(Sirt2)和炎症的影响。方法:将胶原酶Ⅳ注入SD大鼠右侧
纹状体中建立脑出血模型,通过免疫印迹和ELISA 等方法测定大鼠脑出血后48 h 的Sirt2 的表达及炎症变化。利
用Hemin 诱导PC12 细胞损伤模拟体外脑出血模型,并检测Sirt2 及炎症变化;采用短发夹RNA(shRNA)-Sirt2 沉
默Sirt2 在PC12 细胞中的表达及对炎症的影响。结果:手术后48 h 脑出血行为学评分最低。脑出血组Sirt2 的表达
显著高于假手术组。脑出血组IL-6、IL-1β 表达显著升高。结论:脑出血可以促进Sirt2 的表达和炎症反应,降低
Sirt2 的表达可减缓炎症反应。
关键词 脑出血;沉默信息调节 相似文献
9.
《Health & place》2019
The importance of neighbourhood on individual health is widely documented. Less is known about the relative role of objective and subjective reports of neighbourhood conditions, how their effect on health changes as people age, and whether they moderate each other’s impact on health. This study uses the English Longitudinal Study of Ageing (ELSA) to determine whether older adults report worse self-rated health as they age, and whether this differs between objective and subjective measures of neighbourhood. ELSA data contain 53,988 person-years across six waves collected biannually between 2002 and 03 and 2012 and 13. Objective neighbourhood conditions are measured by the 2004 Index of Multiple Deprivation, and subjective neighbourhood conditions are captured by a summative neighbourhood dissatisfaction score. We find both objective and subjective neighbourhood composite scores independently predict poor health. There is no change over time in the probability of reporting poor health by baseline objective or subjective neighbourhood scores, suggesting neighbourhood effects do not compound as older adults age. There is no moderating effect of area dissatisfaction on the relationship between neighbourhood deprivation and health. The findings provide little support for causal neighbourhood effects operating in later life and indicate different causal pathways through which objective and subjective neighbourhood deprivation impact on health. 相似文献
10.
目的:探讨通窍活血汤含药脑脊液对氧糖剥夺/复糖复氧(OGD/R)损伤大鼠脑微血管内皮细胞(BMECs)的保护作用及潜在机制。方法:通过酶消化法提取原代BMECs,并将细胞随机分为6组,分别为正常组,OGD/R组,通窍活血汤(TQHXT)组(20%),尼莫地平(NMDP)组(10μmol·L~(-1)),卡博替尼(BMS)组(1μmol·L~(-1))和合用药组。除正常组外,其余各组细胞在氧糖剥夺2 h后迅速复糖复氧24 h进行OGD/R造模并分组给药。采用细胞免疫荧光染色法鉴定BMECs,观察OGD/R损伤大鼠BMECs的形态学和超微结构改变并检测细胞跨膜电阻(TEER)值变化。用试剂盒检测细胞内一氧化氮(NO)水平、乳酸脱氢酶(LDH)活性、活性氧(ROS)荧光强度和组织型纤溶酶原激活因子(tPA)含量。采用流式细胞术检测细胞内钙离子浓度及细胞凋亡,观察血管新生标记因子CD34的表达,用蛋白免疫印迹法(Western blot)检测细胞中紧密连接蛋白(ZO-1),血管内皮生长因子(VEGF),黏着斑激酶(FAK)和桩蛋白(Paxillin)蛋白的表达情况。结果:与正常组比较,OGD/R组细胞皱缩、变圆,细胞TEER值和细胞中ZO-1蛋白表达显著降低,细胞中NO,LDH及ROS水平显著升高,tPA含量显著降低,细胞中钙离子浓度和细胞凋亡显著增加,细胞中CD34有所表达,VEGF,FAK和Paxillin蛋白表达显著升高(P0. 01);与OGD/R组比较,TQHXT组细胞损伤明显改善,细胞TEER值和细胞中ZO-1蛋白表达显著升高,细胞中NO,LDH及ROS含量显著降低,tPA含量显著升高,细胞中钙离子浓度和细胞凋亡显著减少,细胞中CD34表达增加,VEGF,FAK和Paxillin蛋白表达显著升高(P0. 05,P0. 01)。结论:通窍活血汤含药脑脊液对OGD/R损伤大鼠BMECs具有保护作用,该保护作用可能是通过VEGF/VEGF受体2(R2)/FAK/Paxillin信号通路促进血管生成来发挥作用。 相似文献