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101.
Yan-ping Yanga Lisa E Myersa Ursula McGuinnessa Pele Chonga Yan Kwoka Michel H Kleina Robin E Harknessa 《FEMS immunology and medical microbiology》1997,17(3):187-199
The major outer membrane protein of Moraxella (Branhamella) catarrhalis, CD, was detergent-extracted from the bacterial cell wall and purified to homogeneity in high yields by a simple process. The purified protein appeared to exhibit immunogenic properties similar to those of native CD exposed on the surface of the bacterium. Antibodies to CD raised in mice specifically bound to intact B. catarrhalis, as determined by flow cytometry analysis. The IgG subclass distributions of anti-CD antibodies in sera from mice immunized with purified CD or with B. catarrhalis were also similar. CD was found to be antigenically conserved among a panel of B. catarrhalis isolates, as demonstrated by the consistent reactivities of mouse anti-CD antisera with a common 60 kDa protein on immunoblots. Furthermore, convalescent sera collected from patients with otitis media due to B. catarrhalis infection were found to be reactive with the CD protein by immunoblotting. Finally, the purified protein induced antibodies in guinea pigs and mice that exhibited in vitro bactericidal activity against the pathogen. Therefore, the native CD outer membrane protein represents a potentially useful antigen for inclusion in a vaccine against B. catarrhalis. 相似文献
102.
Michael Haber 《Biometrical journal. Biometrische Zeitschrift》1999,41(5):533-542
Longini , Datta , and Halloran (1996) proposed to design HIV vaccine trials in a way that will permit the simultaneous estimation of the vaccine effects on susceptibility to infection and on infectiousness of vaccine brak-throughs. The main feature of their design is the inclusion of steady partners of trial participants. They estimate four parameters from the vaccine trial: the probability that a susceptible person will become infected from his/her steady partner, the probability of becoming infected from outside the partnership, the vaccine efficacy for susceptibility and the vaccine efficacy for infectiousness. We show how the estimates of these parameters can be used to predict the attack rate in a given population during a specified period following mass-vaccination. This is an iterative method, as the attack rate depends on the HIV prevalence which, in turn, depends on the number of new cases during that period. The same method is also used to estimate the attack rate in that population during the same period in the absence of vaccination. The estimated attack rates allow us to estimate the population vaccination effectiveness, defined as the fraction HIV cases prevented by a vaccination program. 相似文献
103.
Rachel Han Jungyoung Tiffany Shin Jin Kim Yong Seok Choi Young Wook Kim 《Entomological Research》2017,47(3):141-151
The purpose of this paper is to provide an overview of the edible insect industry in South Korea and present suggestions for future pricing and promotion strategies. In the first section of this paper, this study outlines the current status and challenges of the edible insect industry in the food market, the material market, the animal feed market, and the medicinal market. The second section of this paper suggests different pricing and promotion strategies for each market segment. This study describes how the consideration of personal traits, information framing, and increasing familiarity can enhance consumer consumption of insect‐based foods. 相似文献
104.
牛分枝杆菌减毒活疫苗--卡介苗(bacillus Calmette-Guérin,BCG)对预防严重的儿童结核病有效,但其免疫保护效率随儿童年龄增长而降低。BCG不能提供终身免疫保护可能与其诱导的记忆性T细胞主要是寿命较短的效应记忆性T细胞有关。新型结核分枝杆菌蛋白亚单位疫苗将有效的抗原有机组合起来,在适宜的疫苗佐剂辅助下诱导Th1型免疫应答。动物实验表明,增加抗原谱可有效提高亚单位疫苗的保护效率。更重要的是,亚单位疫苗在体内持续时间较短,可诱导寿命较长的中央记忆性T细胞,提供比BCG更持久的免疫保护力。记忆性T细胞的分化受抗原特性与剂量、细胞因子、转录因子及雷帕霉素等的调控。对亚单位疫苗及其诱导的免疫记忆进行研究将对新型结核分枝杆菌疫苗的设计与评价产生积极影响。 相似文献
105.
Ryan Taschuk Erin Scruten Murray Woodbury Neil Cashman Andrew Potter Philip Griebel 《朊病毒》2017,11(5):368-380
The ongoing epidemic of chronic wasting disease (CWD) within cervid populations indicates the need for novel approaches for disease management. A vaccine that either reduces susceptibility to infection or reduces shedding of prions by infected animals, or a combination of both, could be of benefit for disease control. The development of such a vaccine is challenged by the unique nature of prion diseases and the requirement for formulation and delivery in an oral format for application in wildlife settings. To address the unique nature of prions, our group targets epitopes, termed disease specific epitopes (DSEs), whose exposure for antibody binding depends on disease-associated misfolding of PrPC into PrPSc. Here, a DSE corresponding to the rigid loop (RL) region, which was immunogenic following parenteral vaccination, was translated into an oral vaccine. This vaccine consists of a replication-incompetent human adenovirus expressing a truncated rabies glycoprotein G recombinant fusion with the RL epitope (hAd5:tgG-RL). Oral immunization of white-tailed deer with hAd5:tgG-RL induced PrPSc-specific systemic and mucosal antibody responses with an encouraging safety profile in terms of no adverse health effects nor prolonged vector shedding. By building upon proven strategies of formulation for wildlife vaccines, these efforts generate a particular PrPSc-specific oral vaccine for CWD as well as providing a versatile platform, in terms of carrier protein and biological vector, for generation of other oral, peptide-based CWD vaccines. 相似文献
106.
107.
Two pairs of PCR primers were designed according to the sequances of the vaccine strain and virulent strain of CPV. Heminested PCR method was established. Result of the first PCR amplification showed the same amplified products of 574bp length, after the second PCR amplification, the virulent strain produced the length 364bp fragment, but the vaccine strain couldn' t produce that. The products of PCR were examined by electrophoresis and restriction enzyme digestion. The result showed the length of the fragment and enzyme sites were as the same as those designed. The PCR assay of CPV was proved to be specific and sensitive. It shows that this method may be used in discriminating the vaccine strain and virulent strain of CPV or monitoring the vaccinated canine in order to aviod disease and financial losing. 相似文献
108.
109.
Immunizations of New Zealand White rabbits with specific macrophage migration inhibitory factor (MIF) tick peptide (PEP) produced circulating anti-tick PEP antibodies in the hosts. Antibody titers of greater than 1:5000 to tick MIF peptide were observed for crude sera from PEP-immunized rabbits. PEP- and BSA-vaccinated rabbits were infested with Amblyomma americanum adults. Feeding intervals, female weights, egg masses and percent egg hatch were measured for ticks feeding on control and immunized hosts. Feeding intervals were significantly lengthened to 13.3 days for PEP-vaccinated hosts compared to BSA-vaccinated controls at 12.4 days, while female engorgement weights and egg masses were unchanged. By immunizing hosts using specific tick PEP, we were able to alter the length of time the ticks fed on their hosts. 相似文献
110.
The current vaccine for tuberculosis (TB), caused by Mycobacterium tuberculosis (MTB), is an attenuated strain of Mycobacterium bovis bacillus Calmette-Guerin (BCG). BCG has proven to be effective in children, however, efficacy wanes in adulthood. Lactoferrin, a natural protein with immunomodulatory properties, is a potential adjuvant candidate to enhance efficacy of BCG. These studies define bovine lactoferrin as an enhancer of the BCG vaccine, functioning in part by modulating macrophage ability to present antigen and stimulate T-cells. BCG-infected bone marrow derived macrophages (BMMs) cultured with bovine lactoferrin increased the number of MHC II(+) expressing cells. Addition of IFN-gamma and lactoferrin to BCG-infected BMMs enhanced MHC II expressiona dna increased the ratio of CD86/CD80. Lactoferrin treated BCG-infected BMMs were able to stimulate an increase in IFN-gamma production from presensitized CD3(+) splenocytes. Together, these results demonstrate that bovine lactoferrin is capable of modulating BCG-infected macrophages to enhance T-cell stimulation through increased surface expression of antigen presentation and co-stimulatory molecules, which potentially explains the observed in vivo bovine lactoferrin enhancement of BCG vaccine efficacy to protect against virulent MTB infection. 相似文献