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   381篇
  免费   13篇
  国内免费   5篇
儿科学   21篇
妇产科学   2篇
基础医学   41篇
临床医学   18篇
内科学   34篇
皮肤病学   14篇
神经病学   11篇
特种医学   1篇
外科学   6篇
综合类   22篇
预防医学   180篇
眼科学   3篇
药学   31篇
肿瘤学   15篇
  2024年   1篇
  2023年   8篇
  2022年   15篇
  2021年   24篇
  2020年   23篇
  2019年   24篇
  2018年   25篇
  2017年   13篇
  2016年   10篇
  2015年   16篇
  2014年   17篇
  2013年   45篇
  2012年   21篇
  2011年   18篇
  2010年   10篇
  2009年   13篇
  2008年   6篇
  2007年   11篇
  2006年   15篇
  2005年   8篇
  2004年   8篇
  2003年   8篇
  2002年   8篇
  2001年   3篇
  2000年   6篇
  1999年   4篇
  1998年   7篇
  1997年   5篇
  1996年   4篇
  1995年   3篇
  1994年   2篇
  1993年   1篇
  1992年   2篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1987年   2篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1981年   2篇
  1978年   1篇
  1976年   1篇
排序方式: 共有399条查询结果,搜索用时 0 毫秒
81.

Background

Pre-licensure clinical trials for two U.S. licensed tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccines did not reveal any major safety concerns. However, routine use in large adolescent and adult populations could reveal rare and potentially serious adverse events (AEs).

Methods

To characterize reported AEs following Tdap vaccination and identify potential safety concerns warranting further evaluation, we analyzed data from the Vaccine Adverse Event Reporting System (VAERS) and assessed the frequency and proportions of AEs and reporting rates (reports per 100,000 vaccine doses distributed).

Results

A total of 2090 reports (7% were serious; 55% listed Tdap alone) involving Tdap vaccines were submitted to VAERS May 2005–June 2007. The crude reporting rate was 10.2 per 100,000 vaccine doses distributed. The median age of vaccinees was 22 years, and the female to male ratio was about 2 to 1. The majority of reports described common local and systemic signs and symptoms, such as injection site reactions, fever, and headache. Rarely reported AEs included myopericarditis, demyelinating diseases of the central nervous system, Guillain–Barré Syndrome, syncope, encephalopathy/encephalitis, seizure, Bell's palsy, anaphylaxis, and thrombocytopenia.

Conclusions

Because adolescents and adults were not routinely vaccinated against pertussis in the past, this surveillance summary provides important – and reassuring – information about the use of Tdap in these age groups. Although subject to the limitations of passive surveillance, the findings of this VAERS review support the pre-licensure clinical trial data with regard to the safety of the U.S. licensed Tdap vaccines. Continued monitoring of clinically significant AEs that are temporally associated with Tdap vaccination and further assessment of such events using controlled observational studies may provide additional information about the safety of these vaccines.  相似文献   
82.
我国是全球22个结核病高负担国家之一[1].提高患者发现率是我国控制结核病的重点和难点,而肺结核可疑症状者的求医行为模式是决定发现率的关键因素.国外对肺结核可疑症状者求医行为模式的研究多是以社区为基础,而我国的研究则多以医院为基础,鲜见针对社区人群的研究[2,3],其结论难以代表社区中全部可疑症状者.为此本文综述肺结核可疑症状者的求医行为及影响因素,为改善求医行为模式,提高我国结核病患者发现率提供参考依据.  相似文献   
83.
The influence of genetic variability within the major histocompatibility complex (MHC) region on variations in immune responses to childhood vaccination was investigated. The study group consisted of 135 healthy infants who had been immunized with hepatitis B (HBV), 7-valent pneumococcal conjugate (PCV7), and diphtheria, tetanus, acellular pertussis (DTaP) vaccines according to standard childhood immunization schedules. Genotype analysis was performed on genomic DNA using Illumina Goldengate MHC panels (Mapping and Exon Centric). At the 1 year post vaccination check-up total, isotypic, and antigen-specific serum antibody levels were measured using multiplex immunoassays. A number of single nucleotide polymorphisms (SNPs) within MHC Class I and II genes were found to be associated with variations in the vaccine specific antibody responses and serum levels of immunoglobulins (IgG, IgM) and IgG isotypes (IgG1, IgG4) (all at p < 0.001). Linkage disequilibrium patterns and functional annotations showed that significant SNPs were strongly correlated with other functional regulatory SNPs. These SNPs were found to regulate the expression of a group of genes involved in antigen processing and presentation including HLA-A, HLA-C, HLA-G, HLA-H, HLA-DRA, HLA-DRB1, HLA-DRB5, HLA-DQA1, HLA-DQB1, HLA-DOB, and TAP-2. The results suggest that genetic variations within particular MHC genes can influence immune response to common childhood vaccinations, which in turn may influence vaccine efficacy.  相似文献   
84.

Background

An improved nonavalent PorA native outer membrane vesicle vaccine was developed with intrinsic adjuvating activity due to presence of less-toxic (lpxL1) LPS. In the present study, the safety and immunogenicity of this next-generation NonaMen vaccine were evaluated following repeated vaccination in rabbits and mice.

Methods

A repeated–dose toxicology study was performed in rabbits. Immunogenicity of next-generation NonaMen was evaluated by determining the serum bactericidal antibody (SBA) titers against meningococcal serogroup B strains containing several PorA subtypes. Release of the pro-inflammatory cytokine, interleukin-6 (IL-6), by the human monocytic cell line (MM6) was measured to estimate pyrogenic activity.

Results

No toxicologically relevant findings were noted in vaccinated rabbits receiving plain next-generation NonaMen. In agreement, next-generation NonaMen induced reduced amounts of the pro-inflammatory cytokine, IL-6, released by human monocyte cell line. In both rabbits and mice, next-generation NonaMen induced high SBA titers against all tested MenB strains regardless of whether or not aluminium phosphate adjuvant is used.

Conclusions

The data suggest that next-generation NonaMen is a safe vaccine with the potential to develop a broadly protective immune response and encourage the start of the first clinical studies.  相似文献   
85.
《Vaccine》2016,34(3):387-394
BackgroundThe Advisory Committee on Immunization Practices recommends routine childhood vaccination by age 2 years, yet evidence suggests that only 2% to 26% of children receive vaccine doses at age-appropriate times (compliance). The objective of this study was to estimate vaccine completion and compliance rates between birth and age 2 years using recent, nationally representative data.MethodsUsing a sample of children aged 24 to 35 months from the 2012 National Immunization Survey (NIS), the present study examined completion and compliance of recommended childhood vaccines. A state-specific examination of vaccine completion and compliance was also conducted.ResultsAn unweighted sample of 11,710 children (weighted to 4.1 million) was selected. Approximately 70% of children completed all doses of six recommended vaccines by 24 months of age. Completion rates varied by antigen, ranging from 68% completing two or three doses of rotavirus vaccine to 92% completing three doses of inactivated poliovirus vaccine. Vaccine completion rates also varied at different measurement periods, with the lowest rates observed at 18 months. Approximately 26% of children received all doses of six recommended vaccines on time. Among the 74% of children who received at least one late dose, 39% had >7 months of undervaccination. Patterns of completion and compliance also varied by geographic region.ConclusionsCompletion of individual antigens approached Healthy People 2020 targets. However, overall completion of the recommended vaccine series and compliance with the recommended vaccination dosing schedule were low, indicating few children received vaccines at age-appropriate times. Additional clinical, policy, and educational interventions are needed to increase receipt of vaccines at optimal ages.  相似文献   
86.
《Vaccine》2016,34(10):1233-1240
The 1st Workshop on National Immunization Programs and Vaccine Coverage in Association of Southeast Asian Nations (ASEAN) Countries Group (WNIPVC-ASEAN) held a meeting on April 30, 2015, Pattaya, Thailand under the auspices of the Pediatric Infectious Diseases Society and the World Health Organization (WHO). Reports on the current status and initiatives of the national immunization program (NIP) in each ASEAN countries that attended were presented. These reports along with survey data collected from ministries of health in ASEAN countries NIPs demonstrate that good progress has been made toward the goal of the Global Vaccine Action Plan (GVAP). However, some ASEAN countries have fragile health care systems that still have insufficient vaccine coverage of some basic EPI antigens. Most ASEAN countries still do not have national coverage of some new and underused vaccines, and raising funds for the expansion of NIPs is challenging. Also, there is insufficient research into disease burden of vaccine preventable diseases and surveillance. Health care workers must advocate NIPs to government policy makers and other stakeholders as well as improve research and surveillance to achieve the goals of the GVAP.  相似文献   
87.
88.
89.
Tumor vessels abundantly express receptors for vascular endothelial growth factor (VEGF), a mediator of neoangiogenesis. The aim of this study was to specifically target and damage the vasculature of pancreatic cancer (PaCa) by fusing VEGF to diphtheria toxin (DT), which inhibits protein synthesis of target cells. DT-VEGF fusion protein was produced in vector pGEX-KG and expressed in E. coli SG12036. Human PaCa cell lines (HPAF-2 and AsPC-1) and human endothelial cells (HUVEC) were exposed to DT-VEGF (10 ng/ml – 10,000 ng/ml). Proliferation was assessed after 3 days. One mm3 fragments of subcutaneous PaCa donor tumors were implanted into the pancreas of nude mice that received either DT-VEGF (200 ώg/kg) every other day) or phosphate-buffered saline intraperitoneally for 14 weeks. Tumor volume, metastatic spread, and animal weight were determined at autopsy. Microvessel density was analyzed in CD31 -stained tumor sections. Proliferation of PaCa cells was inhibited at high concentrations of DT-VEGF (≥1000 ng/ml). DT-VEGF decreased the growth of HUVEC at 10 ng/ml. In vivo, DT-VEGF reduced tumor volume (HPAF-2, 76%; AsPC-1, 53%), microvessel density (HPAF-2, 54%; AsPC-1, 62%), and tumor spread (HPAF-2, 89%; AsPC-1, 50%). Survival was increased (HPAF-2, 7/8 vs. 4/8 animals; AsPC-1, 6/8 vs. 1/8 animals). Weight was not influenced by DT-VEGF. The DT-VEGF effect is due to its toxic action on the tumor vasculature rather than to direct inhibition of PaCa cell growth. DT-VEGF therapy was not associated with systemic side effects. Presented at the Forty-Second Annual Meeting of The Society for Surgery of the Alimentary Tract, Atlanta, Georgia, May 20–23, 2001. Supported by the R.S. Hirshberg Foundation and the Deutsche Forschungsgemeinschaft (grant HO 1843–1).  相似文献   
90.
通过化学防除试验,研究了不同浓度除草剂在人工点喷和机械茎叶处理对白喉乌头防除效果以及除草剂对禾草类和杂类草产量的影响。结果表明:采用化学防除措施能有效抑制白喉乌头的生长,人工点喷针对性强,基本能够做到全面清除白喉乌头,有利于禾草类和杂类草的增产,对草地植被危害较小;机械处理,也能够明显的抑制白喉乌头的生长繁殖,但是由于其施药方式的影响,对乌头的抑制作用较人工点喷弱,对其他阔叶类植被也产生了一定抑制作用,较长时间后也能促进禾类草的增产。  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