首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1131篇
  免费   22篇
  国内免费   6篇
耳鼻咽喉   6篇
儿科学   26篇
妇产科学   12篇
基础医学   122篇
口腔科学   13篇
临床医学   126篇
内科学   132篇
皮肤病学   12篇
神经病学   77篇
特种医学   24篇
外科学   63篇
综合类   29篇
预防医学   454篇
眼科学   9篇
药学   34篇
肿瘤学   20篇
  2023年   69篇
  2022年   156篇
  2021年   255篇
  2020年   178篇
  2019年   9篇
  2018年   14篇
  2017年   19篇
  2016年   23篇
  2015年   24篇
  2014年   32篇
  2013年   36篇
  2012年   59篇
  2011年   120篇
  2010年   83篇
  2009年   38篇
  2008年   10篇
  2007年   5篇
  2006年   7篇
  2005年   6篇
  2004年   3篇
  2003年   1篇
  1996年   1篇
  1994年   11篇
排序方式: 共有1159条查询结果,搜索用时 31 毫秒
971.
IntroductionThe World Health Organization estimates that approximately 180,000 health care workers have died in the fight against COVID-19. Emergency nurses have experienced relentless pressure in maintaining the health and well-being of their patients, often to their detriment.MethodsThis research aimed to gain an understanding of lived experiences of Australian emergency nurses working on the frontline during the first year of the COVID-19 pandemic. A qualitative research design was used, guided by an interpretive hermeneutic phenomenological approach. A total of 10 Victorian emergency nurses from both regional and metropolitan hospitals were interviewed between September and November 2020. Analysis was undertaken using a thematic analysis method.ResultsA total of 4 major themes were produced from the data. The 4 overarching themes included mixed messages, changes to practice, living through a pandemic, and 2021: here we come.DiscussionEmergency nurses have been exposed to extreme physical, mental, and emotional conditions as a result of the COVID-19 pandemic. A greater emphasis on the mental and emotional well-being of frontline workers is paramount to the success of maintaining a strong and resilient health care workforce.  相似文献   
972.
973.
BackgroundThe novel influenza A H1N1 (A[H1N1]pdm09) strain emerged in 2009, contributing to significant morbidity and mortality. It is not known whether illness associated with A(H1N1) pdm09 in the post-pandemic era exhibits a similar disease profile.ObjectiveThe objectives of this study were to compare the burden of disease of A(H1N1) pdm09 influenza from the 2009 pandemic year to the post-pandemic years (2010–2014), and to explore potential reasons for any differences.Study designWe conducted a retrospective cohort study of inpatients admitted to Children’s Hospital Colorado with a positive respiratory specimen for influenza from May–December, 2009 and December, 2010–April, 2014. Univariate and multivariate analyses were conducted to compare the demographics and clinical characteristics of patients with H1N1 during the two periods.ResultsThere were 388 inpatients with influenza A(H1N1) pdm09 in 2009, and 117 during the post-pandemic years. Ninety-four percent of all H1N1 during the post-pandemic era was observed during the 2013–2014 influenza season. Patients with A(H1N1) pdm09 during the post-pandemic year were less likely to have an underlying medical condition (P < 0.01). Patients admitted to the ICU during the post-pandemic year had a lower median age (5 vs 8 years, P = 0.01) and a lower proportion of patients were intubated, had mental status changes, and ARDS compared with the pandemic years, (P < 0.01 for all), with decreased mortality (P = 0.02).ConclusionPatients with influenza A(H1N1) pdm09 during the post-pandemic years appeared to have less severe disease than patients with A(H1N1) pdm09 during the pandemic year. The reasons for this difference are likely multifactorial.  相似文献   
974.

BACKGROUND:

Survey data suggest that Canadian intensivists administer corticosteroids to critically ill patients primarily in response to airway obstruction, perceived risk for adrenal insufficiency and hemodynamic instability.

OBJECTIVE:

To describe variables independently associated with systemic corticosteroid therapy during an influenza outbreak.

METHODS:

The present analysis was retrospective cohort study involving critically ill patients with influenza in two Canadian cities. Hospital records were reviewed for critically ill patients treated in the intensive care units (ICUs) of eight hospitals in Canada during the 2008 to 2009 and 2009 to 2010 influenza outbreaks. Abstracted data included demographic information, symptoms at disease onset, chronic comorbidities and baseline illness severity scores. Corticosteroid use data were extracted for every ICU day and expressed as hydrocortisone dose equivalent in mg. Multivariable regression models were constructed to identify variables independently associated with corticosteroid therapy in the ICU.

RESULTS:

The study cohort included 90 patients with a mean (± SD) age of 55.0±17.3 years and Acute Physiology and Chronic Health Evaluation II score of 19.8±8.3. Patients in 2009 to 2010 were younger with more severe lung injury but similar exposure to corticosteroids. Overall, 54% of patients received corticosteroids at a mean daily dose of 343±330 mg of hydrocortisone for 8.5±4.8 days. Variables independently associated with corticosteroid therapy in the ICU were history of airway obstruction (OR 4.8 [95% CI 1.6 to 14.9]) and hemodynamic instability (OR 4.6 [95% CI 1.2 to 17.8]).

CONCLUSION:

Observational data revealed that hemodynamic instability and airway obstruction were associated with corticosteroid therapy in the critical care setting, similar to a recent survey of stated practice. Efforts to determine the effects of corticosteroids in the ICU for these specific clinical situations are warranted.  相似文献   
975.

Objectives

Numerous interventions seeking to increase preparedness for pandemic influenza have been implemented, but low compliance of healthcare providers has been reported in many instances. The aim of this study was to identify factors that affect preparedness for pandemic influenza by examining: hospital managers' perceptions of measures implemented to promote preparedness for pandemic influenza; hospital managers' assessments of the readiness and capability of their hospitals to manage pandemic influenza; and the effectiveness of a national pandemic preparedness programme in Israel over time.

Study design

A quasi-experiment was conducted following implementation of a national pandemic preparedness programme in Israel. A survey assessed hospital managers' perceptions of the effectiveness of the programme, and the preparedness and capacity of their hospitals to manage pandemic influenza. Two independent evaluations of preparedness for biological threats were conducted, based on a validated tool that included 60 objective parameters.

Methods

Correlations between perceived preparedness and capacity and components of the preparedness programme were analysed using Statistical Package for the Social Sciences Version 17. Stepwise logistic regression was used to determine the components that influence preparedness and capability to manage pandemic influenza.

Results

All general hospital managers in Israel were approached twice (first and second evaluations). Ninety-one percent rated themselves as highly/very highly prepared for pandemic influenza, and 87% rated themselves as highly/very highly capable of dealing with pandemic influenza. Strong correlation was found between hospital managers' perceived preparedness and capacity to manage pandemic influenza (rho = 0.761, P = 0.000), and between perceived preparedness and familiarity with the disease (rho = 0.605, P = 0.003). Familiarity with guidelines accounted for 35% of the variance in perceived capability (adjusted R2 = 0.346, P = 0.002). Inclusion of preparedness evaluations explained an additional 15% of the variance (R2 change = 0.146, P = 0.026). An increase in mean total score for emergency preparedness was found in the second evaluation compared with the first evaluation.

Conclusions

Familiarity with guidelines and preparedness evaluations affect the perceptions of healthcare managers regarding preparedness and capability to manage pandemic influenza.  相似文献   
976.
BackgroundThe World Health Organization on 11 March 2020, declared COVID-19 as a pandemic. India initiated social distancing measures to combat the epidemic of COVID-19. The course of the epidemic of COVID-19 for India was predicted using stochastic probability–based mathematical modeling.MethodsData synthesis for the top few countries affected was studied for various factors affecting the epidemic. For projections of infected cases for India, the modified susceptible-exposed-infectious-removed/recovered framework modified for the effect of social distancing (Rho) was used. Simulation was carried out for 10,000 runs using Python. Projections for infected cases and hospitalization requirement were estimated.ResultsThe epidemic curve will peak in the third week of June in India with 17,525,869 and 2,153,200 infected people with reproduction number of 1.8 and Rho of 0.7 and 0.6, respectively. Compared with the baseline scenario of no social distancing, for transmissibility with R0 = 1.8, the reduction in infections due to social distancing measure is 78% (Rho = 0.7) and 97% (Rho = 0.6). Similarly for R0 = 2.2 and 2.4, the reduction in infected numbers slightly lowers to 62% and 66% with Rho = 0.7 and 92% and 75% with Rho = 0.6, respectively. With R0 = 1.8 and Rho = 0.6, the Intensive Care Unit (ICU) bed requirement is 107,660, whereas if transmissibility is high, the ICU bed requirement would increase to 1,994,682.ConclusionsThe social distancing measures seem to have been working for India in absence of treatment in sight for COVID-19. Although with the government's response strategy of social distancing, the peak of the epidemic is extended giving more months for preparedness to the country; however, the sustainability of these measures is uncertain.  相似文献   
977.
Background and aimsCOVID-19 pandemic has affected various countries differently due to variance in demographics, income level, health infrastructure, government response, control and enforcement, and cultural traits of different populations. This study aims to identify significant factors behind the unequal distribution of identified cases and deaths in different countries. Our study’s objective is comparative analysis and identification of relations between the spread of COVID-19 pandemic, population characteristics, and government response.MethodsThe top 18 countries worst hit by COVID-19 cases were identified. The data metrics, such as the number of cases, deaths, fatality rates, tests, average life expectancy, and population, were collected and consolidated.ResultsCountries with significant percentage of the older population are vulnerable to a high number of deaths due to COVID-19. Developed countries have higher per capita testing, whereas testing is less intensive in developing/underdeveloped countries. There is a consensus among health experts that COVID-19 has higher fatality rates for people above 60, however, with further age, this increases exponentially. Countries with higher life expectancy are also high-income countries, and the best course of action would be to provide specialized support to self-isolate for people of ages 75 and above.ConclusionThe behaviour of disease occurring at a large scale and interaction with different populations is studied to understand and differentiate the factors and measures that successfully inhibited the pandemic. The study benchmarks different countries based on their performance and efforts against the pandemic and provides some useful insights on the efficiency of their governance and potential to improve & ramp up their programs. The economic status and existing healthcare infrastructure as they are the key factors in determining the country’s ability to contain and minimize the losses from this pandemic.  相似文献   
978.
目的基于焦磷酸测序技术建立甲型H1N1流感病毒血凝素(HA)基因裂解位点突变的快速检测方法,探讨其临床应用价值。方法采用RT-PCR扩增甲型H1N1病毒血凝素基因中的HA片段,在生物信息学分析的基础上,针对甲型H1N1病毒血凝素基因含有裂解位点序列片段,分别设计一套生物素标记的PCR引物和测序引物,运用焦磷酸测序技术对含甲型H1N1病毒裂解位点基因片段进行序列测定,同时分析青岛地区甲型H1N1流感病毒流行株的裂解位点基因特征。结果建立了基于焦磷酸测序技术检测甲型H1N1流感病毒裂解位点突变方法,实现甲型H1N1流感病毒HA基因裂解位点的高通量检测,青岛地区甲型H1N1流感病毒裂解位点344氨基酸序列没有发生变异。结论本研究所建立的方法具有自动化程度高和结果准确等特点,适用于甲型H1N1流感病毒裂解位点进行快速高通量检测。  相似文献   
979.
Recent cases of avian influenza H7N9 have caused great concerns that virus may become transmittable between humans. It is imperative to develop an effective vaccine to fight against the pandemic potential of this H7N9 influenza virus to protect human from the disease. This study aims to investigate an optimized formulation for the development of H7N9 vaccines. Various doses of H7N9 inactivated whole or split-virus antigens (0.5, 1.5, or 3 μg based on hemagglutinin content) combined with squalene-based adjuvant (AddaVAX), aluminum hydroxide Al(OH)3 or without adjuvant were evaluated for the efficacy of H7N9 vaccine regiments in mice. With either H7N9 whole or split-virus based vaccines, AddaVAX-adjuvanted formulations were the most immunogenic in eliciting significant humoral immune response against H7N9 virus and exhibited strong cross-reactive response in hemagglutination inhibition (HAI) and viral-neutralization assays against H7N7 virus as well. In contrast, formulations with Al(OH)3 or without adjuvant were less immunogenic and elicited lower titers of HAI and microneutralization assays against both viruses. Dose-sparing experiments suggested that the formulation with as low as 0.004 μg of split or whole virus vaccine antigens together with 50% AddaVAX provided sufficient sero-protective HAI titers and achieved essential virus-neutralizing antibody titers against H7-subtype influenza viruses in mice. Protection experiments demonstrated that the formulation of 0.004 μg to 0.5 μg of split-virion vaccines with AddaVAX conferred full protection against viral challenge up to 100 LD50 of wild-type H7N9 virus, with 0% survival in placebo group. Taken together, our study demonstrates that squalene-based adjuvant can significantly enhance the protective efficacy of H7N9 virus vaccine and provides a useful strategy to confront the potential pandemic outbreaks of H7N9 virus.  相似文献   
980.
Initiation of mass vaccination is critical in response to influenza pandemic. There is an urgent need of a simple, rapid method for production of influenza vaccine that is more effective than current traditional influenza vaccines. Recent H7N9 transmissions to humans in China with high morbidity/mortality initiated extensive vaccine evaluation. We produced the HA1 domains (amino acids 1-320) from H7N9 and H7N7 strains in E. coli. Both were found to contain primarily monomers/trimers with low oligomeric content. However, when residues from the N-terminal β sheet (first 8 amino acid) of H7 HA1 domains were swapped with the corresponding amino acids from H5N1, functional oligomeric H7 HA1 were produced (HA1-DS), demonstrating strong receptor binding and hemagglutination. In rabbits, the HA1-DS from either H7N9 or H7N7 generated high neutralization titers against both homologous and heterologous H7 strains, superior to the unmodified H7 HA1 proteins. In ferrets, HA1-DS from H7N7 elicited higher (and faster) HI titers, better protected ferrets from lethality, weight loss, and reduced viral loads following challenge with wild-type highly pathogenic H7N7 virus compared with inactivated H7N7 subunit vaccine. HA1-DS vaccinated ferrets were also better protected from weight loss after challenge with the heterologous H7N9 virus compared with inactivated H7N7 subunit vaccine. Importantly, the H7N7 HA1-DS vaccine induced antibody affinity maturation far superior to the inactivated H7N7 subunit vaccine, which strongly correlated with control of viral loads in the nasal washes after challenge with either H7N7 or H7N9 strains. We conclude that N-terminus β sheet domain-swap can be used to produce stable functional oligomeric forms of better recombinant HA1 vaccines in simple, inexpensive bacterial system for rapid response to emerging pandemic threat for the global population.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号