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51.
目的 对广州市越秀区学龄前儿童的流感经济负担进行评估,并针对流感疫苗开展卫生经济学评价,为制定免疫规划策略提供依据。方法 以广州市越秀区托幼机构2019年1—6月发生的9起流感样病例暴发疫情的患病儿童为研究对象,采用问卷调查的方式开展经济负担评估,并以其中1起暴发疫情为基础建立SEIAR动力学模型,模拟不同接种策略下的疫情趋势,评价其经济学效益。结果 患病儿童总经济负担人均1 293.56(95% UI:1 096.23~1 592.84)元,其中直接医疗费用人均422.56(95% UI:320.71~555.29)元,直接非医疗费用人均125.95(95% UI:82.41~188.80)元,间接经济损失人均797.03(95% UI:661.50~938.76)元。在流行季前接种1剂次三价流感疫苗,每投入226.19元,可减少1例流感病例,每投入1元,可获得5.72元效益;接种2剂次三价流感疫苗,每投入178.77元,可减少1例流感病例,每投入1元,可获得7.24元效益;接种四价流感疫苗,每投入315.83元,可减少1例流感病例,每投入1元,可获得4.10元效益。结论 广州市越秀区托幼机构流感样病例暴发疫情经济负担较高,如在流行季前接种2剂次三价流感疫苗,可以获得正效益和最好的效益成本比。  相似文献   
52.
小鼠对HBV DNA疫苗的免疫应答及细胞因子的免疫佐剂效应   总被引:7,自引:1,他引:6  
目的 :观察编码小鼠 IL- 2及 IL- 12的真核表达载体 ,对 HBV DNA疫苗诱导 Balb/ c小鼠 (H- 2 d )免疫应答的调节作用及其对稳定表达 HBs Ag的小鼠肥大细胞瘤 P815细胞 (P 815 - HBV- S)成瘤性的影响。 方法 :肌内注射HBV DNA疫苗及细胞因子真核表达载体 ;背部皮下接种 P 815 - HBV - S细胞 ,观察成瘤情况 ;EL ISA法测定血清抗HBs;4h5 1 Cr释放法检测小鼠脾细胞 CTL 活性。 结果 :免疫 8周后 ,以 p CR3.1- S、p CR3.1- S+IL- 2及 p CR3.1-S+IL- 12免疫的小鼠血清 ,45 0 nm A值分别为 0 .87± 0 .1、1.98± 0 .17及 1.6 7± 0 .15 ,均较 p CR3.1组显著提高(P<0 .0 5 )。CTL 细胞杀伤活性分别为 (5 0 .5± 6 .4) %、(6 1.9± 7.1) %及 (73.3± 8.8) % ,后两组与 p CR3.1- S组比较差异均显著 (P<0 .0 5 )。脾细胞悬液经抗 CD4+ 单克隆抗体处理后 ,CTL细胞杀伤活性分别为 (48.3± 5 .9) %、(5 6 .2± 7.5 ) %和 (75 .6± 9.1) % ,抗 CD8+ 单克隆抗体处理后分别为 (10 .6± 1.4) %、(13.6± 1.9) %和 (16 .9±2 .3) %。对照组成瘤率为 10 0 % ,p CR3.1- S组小鼠成瘤率为 12 .5 % ,p CR3.1- S+IL- 12真核表达载体组成瘤率为0 ,对照组平均存活期和 6周后存活率分别为 2 8.4天和 0天。后两组分别 >38.2天及 45  相似文献   
53.
日本血吸虫多价DNA疫苗pBK-Sj26(Sj32)-Sj23免疫效果的观察   总被引:2,自引:0,他引:2  
为了观察血吸虫病多价DNA疫苗的保护力,将小鼠分成5组空白对照组、空质粒对照组、单价抗原DNA疫苗pBK-CMV-Sj23组、多价抗原DNA疫苗pBK-CMV-Sj26-Sj23和pBK-CMV-Sj32-Sj23组.大量提取各组质粒DNA后,各组于0、3、5周在BALB/c小鼠股四头肌注射相应质粒DNA,9周用血吸虫尾蚴攻击感染,15周剖杀小鼠计算减虫率及减卵率.结果显示与对照组比较,实验组小鼠减虫率及减卵率有极显著性差异(P<0.01);与单价pBK-CMV-Sj23组比较,多价DNA疫苗组的减虫率及减卵率有显著性差异.提示血吸虫多价DNA疫苗诱导小鼠对血吸虫的保护力优于单价DNA疫苗.  相似文献   
54.
National (and global) vaccination provides an opportunity to control the COVID-19 pandemic, which disease suppression by societal lockdown and individual behavioural changes will not. We modelled how vaccination through the UK’s vaccine priority groups impacts deaths, hospital and ICU admissions from COVID-19. We used the UK COVID-19 vaccines delivery plan and publicly available data to estimate UK population by age group and vaccination priority group, including frontline health and social care workers and individuals deemed ‘extreme clinical vulnerable’ or ‘high risk’. Using published data on numbers and distributions of COVID-19-related hospital and ICU admissions and deaths, we modelled the impact of vaccination by age group. We then modified the model to account for hospital and ICU admission, and death among health and social care workers and the population with extreme clinical vulnerability and high risk. Our model closely matches the government’s estimates for mortality after vaccination of priority groups 1–4 and groups 1–9. The model shows vaccination will have a much slower impact on hospital and ICU admissions than on deaths. The early prioritisation of healthcare staff and clinically vulnerable patients increases the impact of vaccination on admissions and also protects the healthcare service. An inflection point, when 50% of the adult population has been vaccinated – with deaths reduced by 95% and hospital admissions by 80% – may be a useful point for re-evaluating vaccine prioritisation. Our model suggests substantial reductions in hospital and ICU admissions will not occur until late March and into April 2021.  相似文献   
55.
Lung transplant recipients are at high risk for herpes zoster and preventive measures are a significant unmet need. We investigated the safety and immunogenicity of two doses of a recombinant zoster vaccine (RZV) in lung transplant recipients (≥50 years). We enrolled 50 patients of which 49 received at least one vaccine dose. Anti-glycoprotein E (gE) antibody levels (n = 43) increased significantly compared to baseline (median optical density [OD] 1.96; interquartile range [IQR]: 1.17–2.89) after the first (median OD 3.41, IQR 2.54–3.81, p < .0001) and second vaccine dose (median OD 3.63, IQR 3.39–3.86, p < .0001). gE-specific polyfunctional CD4+ T cell frequencies (n = 38) also increased from baseline (median 85 per 106 CD4+ T cells; IQR: 46–180) to the first (median 128 per 106 CD4+ T cells; IQR: 82–353; p = .023) and after the second dose (median 361 per 106 CD4+ T cells; IQR: 146–848; p < .0001). Tenderness (83.0%; 95%CI: 69.2–92.4%) and redness (31.9%; 95%CI: 19.1–47.1%) at injection site were common. One rejection episode within 3 weeks of vaccination was observed. This is the first study demonstrating that RZV was safe and elicited significant humoral and cell-mediated immunity in lung transplant recipients. RZV is a new option for the prevention of shingles in this population.  相似文献   
56.
目的了解山东省卡介苗(BCG)淋巴结炎经济负担情况。方法以2011年5月至2019年12月山东省304例申请省级补偿的BCG淋巴结炎病例为对象,收集患者基本情况、预防接种相关情况、门诊(住院)病历和收费票据等相关资料,对其直接经济负担(包括直接医疗费用和直接非医疗费用)、间接经济负担和总经济负担进行测算,比较不同特征病例经济负担的差异。结果304例BCG淋巴结炎患者月龄的M(Q1,Q3)为3(2,4)月,其中男性239例(78.6%),淋巴结破溃71例(23.4%),手术227例(74.7%)。单纯门诊、单纯住院和门诊后住院病例分别占25.7%(78例)、7.2%(22例)和67.1%(204例)。贴现后单例直接、间接和总经济负担的M(Q1,Q3)分别为9910(5713,16074)、2081(1547,3122)和12262(7694,18571)元。直接医疗费用占直接经济负担的89.4%,直接经济负担占总经济负担的84.9%,80.0%病例的总经济负担仅占其补偿金额的20.0%左右,只有2.3%的病例总经济负担占补偿金额的60.0%以上。单纯住院和门诊后住院病例的直接、间接和总经济负担高于单纯门诊病例,手术病例的直接、间接和总经济负担高于非手术病例,淋巴结未破溃病例的直接和总经济负担高于破溃病例(均P<0.05)。结论山东省BCG淋巴结炎病例经济负担受诊疗方式的影响,且以直接医疗费用为主。  相似文献   
57.
BackgroundHuman papillomavirus (HPV) vaccine has been increasingly discussed in mainland China since its first approval in 2016. To date, nearly all studies assessing HPV vaccine perceptions and attitudes were implemented during pre-licensure period. Therefore, the nationwide post-marketing survey was conducted to update knowledge, attitudes and practice on HPV vaccine among general population in mainland China.MethodsParticipants aged 18–45 years living in mainland China were recruited in April 2019 by multi-stage non-randomized sampling. Sociodemographic factors, HPV and HPV vaccine related awareness, knowledge, attitudes, vaccine uptake and potential obstacles were assessed in questionnaires. Bivariate analysis and multivariate regression were used to identify disparity among subgroups with different sociodemographic characteristics.Results4,000 women (32.1 ± 7.81y) and 1,000 men (31.8 ± 7.96y) were included in final analysis. Less than one third of participants had heard of HPV (female: 31%; male: 22%) and HPV vaccine (female: 34%; male: 23%). Knowledge score was also unfavorable on HPV (female: 3 out of 13; male: 1.8 out of 13) and HPV vaccine (female: 3 out of 6; male: 2 out of 5). Only 3% females had been vaccinated three years after HPV licensure in China, although willingness to get vaccinated among those unvaccinated were high (mean willingness score ± SD: female: 3.3 ± 0.97; male: 3.0 ± 0.98). Industry of employment and household income were the major factors related to awareness and knowledge of vaccine, whereas HPV and HPV vaccine awareness were key influential factors for willingness. The main obstacles of vaccination were safety concerns, lack of knowledge, and high price of HPV vaccines.ConclusionsFindings highlight a lack of vaccine awareness, knowledge, and poor uptake in mainland China and underscore the necessity of health education campaigns. The identified priority groups, contents to be delivered and practical obstacles could furthermore provide insight into health education to reduce disparities and accelerate HPV vaccine roll-out in China.  相似文献   
58.
The only effective measure to decrease morbidity and mortality caused by the influenza virus in the human population is worldwide vaccination. Vaccination produces neutralizing antibodies that target the HA1 subunit of the HA (hemagglutinin) protein and are strain specific. The effectiveness of new influenza vaccines are linked to two factors, the correct prediction of the circulating strains in the population in a particular season and the concentration of the HA1 protein in the vaccine formulation. With the advent of the licensing of quadrivalent vaccines, pharmaceutical manufacturers are under considerable pressure due to time constraints and dedicated resources to deliver 194–198 million doses (2020–2021 U.S. market) of vaccine. Considering the valuable resources needed to produce the influenza vaccine in a timely manner, the efficient quantitation of the HA1 protein (the main component in the influenza vaccine) is required. Currently the only method approved by regulatory agencies for quantitation of the HA antigen in vaccines is the single radial immunodiffusion assay (SRID), an antibody dependent assay that is not time efficient. Time efficient methods that are antibody independent e.g. reverse phase-high performance liquid chromatography (RP-HPLC) or size exclusion-HPLC (SE-HPLC) are available. An improved method implementing reverse phase-ultra performance liquid chromatography (RP-UPLC) has been developed to quantitate the HA1 protein antigen present in the high yield reassortant vaccine seed viruses from influenza A H1N1 and H3N2 subtypes harvested from inoculated embryonated chicken eggs. This method differentiates between high yield and lower yielding reassortants in order to select the best vaccine candidate seed virus with the highest growth ‘in ovo’. This direct capability to monitor the HA1 concentration of potential reassortant seed viruses and to choose the best yielding HA influenza reassortant when faced with multiple viral seed candidates provides a major advantage on the industrial scale to the influenza vaccine process.  相似文献   
59.
BackgroundThe evaluation of immune responses to RTS,S/AS01 has traditionally focused on immunoglobulin (Ig) G antibodies that are only moderately associated with protection. The role of other antibody isotypes that could also contribute to vaccine efficacy remains unclear. Here we investigated whether RTS,S/AS01E elicits antigen-specific serum IgA antibodies to the vaccine and other malaria antigens, and we explored their association with protection.MethodsNinety-five children (age 5–17 months old at first vaccination) from the RTS,S/AS01E phase 3 clinical trial who received 3 doses of RTS,S/AS01E or a comparator vaccine were selected for IgA quantification 1 month post primary immunization. Two sites with different malaria transmission intensities (MTI) and clinical malaria cases and controls, were included. Measurements of IgA against different constructs of the circumsporozoite protein (CSP) vaccine antigen and 16 vaccine-unrelated Plasmodium falciparum antigens were performed using a quantitative suspension array assay.ResultsRTS,S vaccination induced a 1.2 to 2-fold increase in levels of serum/plasma IgA antibodies to all CSP constructs, which was not observed upon immunization with a comparator vaccine. The IgA response against 13 out of 16 vaccine-unrelated P. falciparum antigens also increased after vaccination, and levels were higher in recipients of RTS,S than in comparators. IgA levels to malaria antigens before vaccination were more elevated in the high MTI than the low MTI site. No statistically significant association of IgA with protection was found in exploratory analyses.ConclusionsRTS,S/AS01E induces IgA responses in peripheral blood against CSP vaccine antigens and other P. falciparum vaccine-unrelated antigens, similar to what we previously showed for IgG responses. Collectively, data warrant further investigation of the potential contribution of vaccine-induced IgA responses to efficacy and any possible interplay, either synergistic or antagonistic, with protective IgG, as identifying mediators of protection by RTS,S/AS01E immunization is necessary for the design of improved second-generation vaccines.Clinical trial registration: ClinicalTrials.gov: NCT008666191.  相似文献   
60.
Pertussis is a globally distributed infectious disease that is a significant cause of morbidity and mortality, especially in infants who are too young to be immunized. This disease is common in childhood, and when it occurs during the first few months of life, it leads to hospitalization and, sometimes, death. Brazil has adopted the strategy of maternal immunization against pertussis in late 2014. This study aims to analyze public data on the disease to determine whether there was an impact on the disease burden following the introduction of the vaccine Tdap in pregnant women and its magnitude. We performed a time-series analysis of the incidence of pertussis between October 2010 and January 2019. We stratified the population of interest into three groups: infants aged less than two months old, infants aged two to six months, and infants aged six months to one year, according to Brazil's vaccination schedule. We found a protective effect of maternal vaccination in all age groups, more prominent on the first group. Before the intervention, infants under two months had a higher risk of getting pertussis in comparison with infants two to six months old (HR 1.15, CI 95%: 1.11–1.19). After the intervention, age under two months is a protective factor compared with two to six months (HR 0.90, CI 95%: 0.82–0.98). The pertussis incidence reduced in all age groups and all Brazil's Regions.  相似文献   
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