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   21368篇
  免费   1344篇
  国内免费   475篇
耳鼻咽喉   184篇
儿科学   537篇
妇产科学   185篇
基础医学   2469篇
口腔科学   132篇
临床医学   1614篇
内科学   2866篇
皮肤病学   225篇
神经病学   421篇
特种医学   460篇
外国民族医学   1篇
外科学   1007篇
综合类   2239篇
现状与发展   1篇
一般理论   2篇
预防医学   7030篇
眼科学   63篇
药学   2257篇
  6篇
中国医学   420篇
肿瘤学   1068篇
  2024年   7篇
  2023年   607篇
  2022年   855篇
  2021年   1151篇
  2020年   999篇
  2019年   839篇
  2018年   856篇
  2017年   772篇
  2016年   819篇
  2015年   902篇
  2014年   1396篇
  2013年   1689篇
  2012年   1275篇
  2011年   1434篇
  2010年   1172篇
  2009年   1138篇
  2008年   825篇
  2007年   936篇
  2006年   790篇
  2005年   674篇
  2004年   629篇
  2003年   538篇
  2002年   405篇
  2001年   396篇
  2000年   327篇
  1999年   294篇
  1998年   199篇
  1997年   192篇
  1996年   134篇
  1995年   108篇
  1994年   93篇
  1993年   81篇
  1992年   63篇
  1991年   70篇
  1990年   69篇
  1989年   68篇
  1988年   57篇
  1987年   57篇
  1986年   47篇
  1985年   67篇
  1984年   38篇
  1983年   19篇
  1982年   28篇
  1981年   17篇
  1980年   13篇
  1979年   13篇
  1978年   9篇
  1977年   4篇
  1974年   4篇
  1972年   4篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
61.
《Vaccine》2022,40(6):924-933
The European Clinical Trial Regulation No 536/2014 is the first mandate for a non-technical, publicly disclosed, plain language summary (PLS) of clinical trial results. This easy-to-understand summary has the potential to inform the public about clinical trial results and thereby improve health literacy in vaccines.To investigate the utility of the PLS, we undertook 2 online surveys (July/October 2020) in the United Kingdom, the United States and India. Participants were selected by quota sampling to ensure representation of gender, age and parental status. Those lacking interest in vaccine clinical research were excluded. In survey 1, participants were questioned about their interest in and expectations of vaccine trial results. In survey 2, the perceptions of participants to a range of written communication styles used in publicly available PLSs were evaluated.A total of 66 (13%) and 122 (29%) individuals were excluded solely due to lack of interest in vaccine clinical research in surveys 1 and 2, respectively; 450 respondents (150/country) completed survey 1 and 300 (100/country) completed survey 2. In survey 1, there was a correlation (p < 0.01) between claimed knowledge of and trust in vaccines. Healthcare professionals were the most trusted source for vaccine information, while vaccine companies were ranked relatively low. In survey 2, infographic PLS formats were considered easiest to understand, most engaging and the strongest communicators. Emphasizing the main points of the infographics in the text did not improve comprehension or recall. Most respondents (86%) indicated that they would like to see this type of communication in the future.Overall, this research suggests that the PLS, by optimizing content and format, has a potential to increase health literacy, and thereby, as part of a wider integrated communication strategy, build vaccine knowledge and confidence.  相似文献   
62.
《Vaccine》2022,40(12):1872-1878
BackgroundThe MenB-FHbp vaccine (Trumenba®) is licensed in various countries for the prevention of meningococcal serogroup B disease in individuals ≥ 10 years of age. The clinical development program included 11 completed trials where, in each trial, MenB-FHbp had an acceptable safety profile after a primary vaccination series was administered to individuals 10–65 years of age. However, the detection of potential rare events was limited because of individual clinical trial size. The current safety analysis evaluates pooled reactogenicity and other adverse events (AEs) reported in these trials to identify new safety signals not detectable in individual trials.MethodsEleven trials contributed safety data, of which 10 recorded local and systemic reactogenicity events; 8 of the trials were controlled, and reactogenicity data were pooled for 7 of these 8 trials. Additional AE evaluations included immediate AEs (IAEs), medically attended AEs (MAEs), serious AEs (SAEs), newly diagnosed chronic medical conditions (NDCMCs), and autoimmune or neuroinflammatory conditions.ResultsLocal and systemic reactions were more frequent in the MenB-FHbp group (n = 15,294) compared with controls (n = 5509), although most reactions were transient and mild to moderate in severity. Frequencies of IAEs, SAEs, MAEs, NDCMCs, and autoimmune or neuroinflammatory conditions were similar between the MenB-FHbp and control groups.ConclusionsMenB-FHbp demonstrated a favorable safety and tolerability profile in the clinical development program of > 15,000 vaccine recipients ≥ 10 years of age. No new safety signals were identified in the pooled analysis compared with data from the individual trials. Continued postmarketing safety surveillance is important for the identification of rare events.Clinicaltrials.gov: NCT01299480; NCT000808028; NCT00879814; NCT00780806; NCT01352845; NCT01352793; NCT01461993; NCT01323270; NCT01830855; NCT01461980; NCT01768117.  相似文献   
63.
《Survey of ophthalmology》2022,67(6):1647-1684
Managing pediatric corneal disorders is challenging as the prognosis of pediatric keratoplasty depends on several factors. Advancements in the genetic basis of congenital corneal diseases and investigations in congenital corneal conditions provide a better understanding of pediatric corneal conditions. Surgeons performing keratoplasty in children now have a choice of various techniques. Evolving surgical techniques of anterior lamellar and endothelial keratoplasties have expanded the management interventions in these pediatric corneal morbidity conditions; however, considerable concerns still exist in association with corneal transplantation in infants and children. Outcomes in pediatric keratoplasty depend upon the preoperative indications, the timing of surgical intervention, intraoperative and postoperative factors including the patient/care givers’ compliance. Factors such as low scleral rigidity, higher rate of graft failure, need for frequent examinations under anesthesia, and difficulty in optimal visual acuity assessment still remain a considerable challenge in pediatric scenarios. In children, deprivation amblyopia as a result of the corneal opacification can adversely affect visual development, causing dense amblyopia. Outcomes to surgical interventions for management of corneal opacification in children are further compromised by the preexisting amblyopia apart from the concerns of refractive outcome of the graft. Graft rejection, graft infection, amblyopia, and glaucoma continue to be serious concerns. In recent years both anterior and posterior lamellar keratoplasty techniques are being increasingly performed in pediatric eyes, which offer advantages in the form of lower risk of graft rejection. The timing of surgery, careful case selection, cautious intraoperative approach, and optimal postoperative management can improve the anatomical and functional outcome in difficult cases.  相似文献   
64.
《Vaccine》2022,40(43):6206-6210
While in Switzerland, pneumococcal vaccination is recommended for adult patients with axial spondyloarthritis (axSpA) treated with biological drugs, since 2014, little is known about the vaccination status of this specific patient population. This study assessed their vaccination status as part of a larger online survey by the ankylosing spondylitis association of Switzerland (SVMB). Out of 1560 who participated in the survey, 834 (53.5%) were eligible for the analysis. Vaccine coverage was low at 32.5% (271/834). Women and patients who got a flu shot every year were more likely to be covered. Age was negatively associated with being vaccinated. Most (54.2%; 147/271) were vaccinated by their general practitioner. Almost two-thirds of those who had not received the vaccine stated that it had not been offered to them (64.1%; 302/471). In summary, the vaccination coverage is low, but might be increased if the vaccine was offered systematically by general practitioners and specialists.  相似文献   
65.
66.
Neonatal encephalopathy (NE) is a significant complication of the peripartum period. It can lead to lifelong neurologic disabilities, including cerebral palsy, cognitive impairments, developmental delays, and epilepsy. Induced hypothermia is the first therapy, which has shown promise in improving the outcomes for neonates with moderate to severe NE following a presumed intrapartum insult.NE is also a frequent source of medical malpractice litigation. In this paper, we will review salient features of the American Tort System as it pertains to medical malpractice. We will discuss the obstetric medico-legal implications of therapeutic hypothermia and suggest a five-step approach to analyzing neonatal cases for causation, etiology, timing of occurrence, responsibility, and liability. We will close with three illustrative clinical cases.  相似文献   
67.
68.
《Vaccine》2021,39(29):3862-3870
Bacillus anthracis, the causative agent of anthrax, continues to be a prominent biological warfare and bioterrorism threat. Vaccination is likely to remain the most effective and user-friendly public health measure to counter this threat in the foreseeable future. The commercially available AVA BioThrax vaccine has a number of shortcomings where improvement would lead to a more practical and effective vaccine for use in the case of an exposure event. Identification of more effective adjuvants and novel delivery platforms is necessary to improve not only the effectiveness of the anthrax vaccine, but also enhance its shelf stability and ease-of-use. Polyanhydride particles have proven to be an effective platform at adjuvanting the vaccine-associated adaptive immune response as well as enhancing stability of encapsulated antigens. Another class of adjuvants, the STING pathway-targeting cyclic dinucleotides, have proven to be uniquely effective at inducing a beneficial inflammatory response that leads to the rapid induction of high titer antibodies post-vaccination capable of providing protection against bacterial pathogens. In this work, we evaluate the individual contributions of cyclic di-GMP (CDG), polyanhydride nanoparticles, and a combination thereof towards inducing neutralizing antibody (nAb) against the secreted protective antigen (PA) from B. anthracis. Our results show that the combination nanovaccine elicited rapid, high titer, and neutralizing IgG anti-PA antibody following single dose immunization that persisted for at least 108 DPI.  相似文献   
69.
《Vaccine》2021,39(38):5391-5400
BackgroundOral rotavirus vaccine (RVV) immunogenicity is considerably lower in low- versus high-income populations; however, the mechanisms underlying this remain unclear. Previous evidence suggests that the gut microbiota may contribute to differences in oral vaccine efficacy.MethodsWe performed whole metagenome shotgun sequencing on stool samples and measured anti-rotavirus immunoglobulin A in plasma samples from a subset of infants enrolled in a cluster randomized 2 × 2 factorial trial of improved water, sanitation and hygiene and infant feeding in rural Zimbabwe (SHINE trial: NCT01824940). We examined taxonomic microbiome composition and functional metagenome features using random forest models, differential abundance testing and regression analyses to explored associations with RVV immunogenicity.ResultsAmong 158 infants with stool samples and anti-rotavirus IgA titres, 34 were RVV seroconverters. The median age at stool collection was 43 days (IQR: 35–68), corresponding to a median of 4 days before the first RVV dose. The infant microbiome was dominated by Bifidobacterium longum. The gut microbiome differed significantly between early (≤42 days) and later samples (>42 days) however, we observed no meaningful differences in alpha diversity, beta diversity, species composition or functional metagenomic features by RVV seroconversion status. Bacteroides thetaiotaomicron was the only species associated with anti-rotavirus IgA titre. Random forest models poorly classified seroconversion status by both composition and functional microbiome variables.ConclusionsRVV immunogenicity is low in this rural Zimbabwean setting, however it was not associated with the composition or function of the early-life gut microbiome in this study. Further research is warranted to examine the mechanisms of poor oral RVV efficacy in low-income countries.  相似文献   
70.
《Vaccine》2021,39(40):5858-5865
BackgroundEnteric fever, caused by Salmonella Typhi and S. Paratyphi, is a cause of high morbidity and mortality among children in South Asia. Rising antimicrobial resistance presents an additional challenge. Typhoid Conjugate Vaccines (TCV) are recommended by the World Health Organization for use among people 6 months to 45 years old living in endemic settings. This study aimed to assess the effectiveness of TCV against culture-confirmed S. Typhi in Lyari Town, Karachi, Pakistan. This peri-urban town was one of the worst affected by the outbreak of extensively drug resistant (XDR) typhoid that started in November 2016.MethodsA matched case-control study was conducted following a mass immunization campaign with TCV at three key hospitals in Lyari Town Karachi, Pakistan. Children aged 6 months to 15 years presenting with culture-confirmed S. Typhi were enrolled as cases. For each case, at least 1 age-matched hospital control and two age-matched community controls were enrolled. Adjusted odds ratios with 95% confidence intervals (CIs) were calculated using conditional logistic regression.ResultsOf 82 typhoid fever patients enrolled from August 2019 through December 2019, 8 (9·8%) had received vaccine for typhoid. Of the 164 community controls and 82 hospital controls enrolled, 38 (23·2%) community controls and 27 (32·9%) hospital controls were vaccinated for typhoid. The age and sex-adjusted vaccine effectiveness was found to be 72% (95% CI: 34% − 88%). The consumption of meals prepared outside home more than once per month (adjusted odds ratio: 3·72, 95% CI: 1·55- 8·94; p-value: 0·003) was associated with the development of culture-confirmed typhoid.ConclusionA single dose of TCV is effective against culture confirmed typhoid among children aged 6 months to 15 years old in an XDR typhoid outbreak setting of a peri-urban community in Karachi, Pakistan.  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