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   487篇
  免费   17篇
  国内免费   5篇
耳鼻咽喉   52篇
儿科学   6篇
妇产科学   4篇
基础医学   66篇
口腔科学   1篇
临床医学   23篇
内科学   21篇
神经病学   53篇
特种医学   2篇
外科学   31篇
综合类   34篇
预防医学   97篇
眼科学   7篇
药学   98篇
中国医学   7篇
肿瘤学   7篇
  2024年   2篇
  2023年   9篇
  2022年   20篇
  2021年   19篇
  2020年   17篇
  2019年   20篇
  2018年   13篇
  2017年   21篇
  2016年   24篇
  2015年   22篇
  2014年   27篇
  2013年   44篇
  2012年   34篇
  2011年   38篇
  2010年   23篇
  2009年   34篇
  2008年   20篇
  2007年   18篇
  2006年   10篇
  2005年   13篇
  2004年   14篇
  2003年   4篇
  2002年   8篇
  2001年   9篇
  2000年   5篇
  1999年   2篇
  1998年   1篇
  1997年   5篇
  1996年   3篇
  1995年   6篇
  1994年   3篇
  1993年   2篇
  1992年   3篇
  1990年   4篇
  1989年   2篇
  1988年   2篇
  1987年   1篇
  1986年   1篇
  1985年   2篇
  1983年   1篇
  1982年   2篇
  1980年   1篇
排序方式: 共有509条查询结果,搜索用时 8 毫秒
81.
Objective To determine the immune responses induced by recombinant Salmonella ty-phimurium expressing the secreting antigen ESAT-6 of Mycobacterium tuberculosis. Methods ESAT-6 cod-ing gene was cloned and identified by PCR and sequencing. Prokaryotic expression plasmid pYA33-esat car-rying the ESAT-6 coding sequence was constructed firstly and electro-transformed into an attenuated strain X4550 of Salmonella typhimurium, the recombinant bacteria was named as X4550(33-esat). C57BL/6 mice were immunized intranasally (I. N) with 108 CFU recombinant bacteria at day 0 and 18. Cells from spleen, lung, mesenteric lymph node (MLN) and Peyer's patch (PP) were collected from mice after second immu-nization, and the specific IFN-γ-secreting cells and IL-4-secreting cells were detected by ELISPOT assay u-sing ESAT-6 peptide as stimulus. Furthermore, CTL effects were in vivo evaluated by CFSE assay. Results The results showed that cellular immune responses specific for ESAT-6 could be detected by ELISPOT assay. In lung and PP cells, immune responses against ESAT-6 were biased toward Th1 type, the frequency of IFN-γ-secreting cells was much higher than that of IL-4-secreting cells. In splenocytes and MLN cells, the anti-gen specific immune responses acted as Thl and Th2 balance, the frequency of IFN-γ-secreting cells was close to that of IL-4-secreting cells. CFSE assay indicated that recombinant bacteria could induce the high level of CTL effects specific for ESAT-6 peptide. Conclusion These results suggested that recombinant Sal-monella typhimurium X4550(33-esat) not only can induce cellular immune responses, but also can elicit specific CTL responses after I. N immunization. It also provided the useful information for the control of infec-tious disease of tuberculosis.  相似文献   
82.
目的本文基于临床经验和循证医学证据制定的鼻炎(萎缩性鼻炎除外)分类和诊疗的专家共识,其中在治疗方面重点关注了鼻腔局部用药的临床应用,旨在进一步规范鼻炎尤其是慢性鼻炎的诊疗,明确鼻腔局部用药如鼻用糖皮质激素、鼻用抗组胺药和鼻腔盐水盥洗等在鼻炎治疗中的临床地位及注意事项,以便指导临床医师进行合理用药,提高鼻炎的疗效和患者的满意度。  相似文献   
83.
王鋆 《实用防盲技术》2013,8(3):109-111
目的报告改良鼻内窥镜下泪囊鼻腔造孔术的手术方法和疗效。方法采用改良鼻内窥镜下泪囊鼻腔造孔术,治疗慢性泪囊炎共69例(75眼)。结果治愈66眼,好转4眼,无效5眼,总有效率93.33%(70/75)。结论改良鼻内镜下泪囊鼻腔造孔术,可有效防止泪囊造孔的狭窄闭锁,提高了手术成功率。  相似文献   
84.
85.
Bioavailability of intranasal formulations of dihydroergotamine   总被引:1,自引:0,他引:1  
Objective: A comparison of the pharmacokinetic properties of two novel intranasal preparations of dihydroergotamine mesilate (DHEM) with a commercially available intranasal preparation. Methods: Two intranasal formulations of DHEM in combination with randomly methylated β-cyclodextrin (RAMEB) were prepared. Subsequently, in an open, randomised, crossover study in nine healthy volunteers, the following medication was administered: 2 mg DHEM/2% RAMEB nasal spray ( =two puffs of 100 μl); 2 mg DHEM/4 mg RAMEB nasal powder; 2 mg Diergo nasal spray ( =four puffs of 125 μl); 0.5 mg DHEM i.m., and 2 mg DHEM solution p.o. Results: No statistically significant differences were found in maximum plasma concentration (Cmax), time to reach Cmax (tmax), area under plasma concentration–time curve (AUC0–8 h), Frel(t=8 h) and Cmax/ AUC(t=8 h) for the three intranasal preparations. The relative bioavailabilities of the DHEM/RAMEB nasal spray, the DHEM/RAMEB nasal powder and the commercially available DHEM nasal spray were 25%, 19% and 21%, respectively, in comparison with i.m. administration. The relative bioavailability after oral administration was 8%. Conclusion: The pharmacokinetic properties of the novel intranasal preparations are not significantly different from the commercially available nasal spray. Advantages of the DHEM/RAMEB nasal spray are (1) less complicated handling, (2) reduction of the number of puffs and (3) a preference by the volunteers. Received: 12 February 1999 / Accepted in revised form: 23 August 1999  相似文献   
86.
Zhang L  Bai R  Li B  Ge C  Du J  Liu Y  Le Guyader L  Zhao Y  Wu Y  He S  Ma Y  Chen C 《Toxicology letters》2011,207(1):73-81
The rising commercial use and large-scale production of engineered nanoparticles (NPs) may lead to unintended exposure to humans. The central nervous system (CNS) is a potential susceptible target of the inhaled NPs, but so far the amount of studies on this aspect is limited. Here, we focus on the potential neurological lesion in the brain induced by the intranasally instilled titanium dioxide (TiO2) particles in rutile phase and of various sizes and surface coatings. Female mice were intranasally instilled with four different types of TiO2 particles (i.e. two types of hydrophobic particles in micro- and nano-sized without coating and two types of water-soluble hydrophilic nano-sized particles with silica surface coating) every other day for 30 days. Inductively coupled plasma mass spectrometry (ICP-MS) were used to determine the titanium contents in the sub-brain regions. Then, the pathological examination of brain tissues and measurements of the monoamine neurotransmitter levels in the sub-brain regions were performed. We found significant up-regulation of Ti contents in the cerebral cortex and striatum after intranasal instillation of hydrophilic TiO2 NPs. Moreover, TiO2 NPs exposure, in particular the hydrophilic NPs, caused obvious morphological changes of neurons in the cerebral cortex and significant disturbance of the monoamine neurotransmitter levels in the sub-brain regions studied. Thus, our results indicate that the surface modification of the NPs plays an important role on their effects on the brain. In addition, the difference in neurotoxicity of the two types of hydrophilic NPs may be induced by the shape differences of the materials. The present results suggest that physicochemical properties like size, shape and surface modification of the nanomaterials should be considered when evaluating their neurological effects.  相似文献   
87.
以全身疾病为治疗目的的中药鼻腔给药具有悠久的历史,近年来中药鼻腔给药的临床应用发展迅速,涉及疼痛、中枢神经系统疾病、心血管疾病、感冒发热、乳腺炎等疾病的治疗,均取得良好效果,本文对近年来中药鼻腔给药的临床应用进展进行综述。  相似文献   
88.
BALB/c mice were immunized intranasally with either soluble ovalbumin (OVA) or OVA entrapped in liposomes. The effect of adding Sigma cholera toxin B subunit (sCT-B), which contained low amounts of cholera holotoxin (CT), or recombinant CT-B (rCT-B) which was free from CT, as mucosal adjuvants was also investigated. The mucosal [lung enzyme-linked immunospot assay (ELISPOT), lung washing] and systemic (serum antibody and spleen ELISPOT) responses of immunized mice to OVA and CT-B were determined. Results showed that soluble OVA and liposome-entrapped OVA were poor inducers of mucosal or systemic responses unless CT-B was added as adjuvant. The types of responses augmented by sCT-B and rCT-B were different. CT-B containing low levels of CT (i.e. sCT-B) boosted both mucosal and systemic IgA and IgG responses, whereas rCT-B only increased IgG responses, unless antigen was entrapped in liposomes. Although rCT-B was unable to adjuvant IgA responses against soluble OVA, it was able to induce IgA responses against itself. These data show that mucosal responses can be increased by addition of CT-B containing low levels of CT to antigen preparations given intranasally, suggesting a direct role for CT-A in isotype switching. Furthermore, the ability of CT-B to adjuvant IgA responses against added antigens and its ability to induce responses against itself appear to be separate phenomena. The results from this study should assist the rational formulation of mucosal vaccines which induce potent mucosal and systemic immune responses.  相似文献   
89.
90.
The immunogenicity and protective efficacy in mice of intranasally (i.n.) administrated influenza subunit antigens together with lipid-based adjuvants (Eurocine®) were compared to those of subcutaneous (s.c.) immunisation. Influenza hemagglutination inhibition (HAI) and ELISA IgG titers were similar in the group's vaccinated s.c. and after i.n. vaccination with adjuvants. The virus-specific IgA levels in serum were higher after vaccination i.n. with adjuvant than after s.c immunisation. Virus-specific IgA was measurable in nasal washings only after i.n vaccinations, with and without adjuvants. Thus, i.n. vaccination with the endogenous non-toxic, lipid adjuvants induced equal or stronger antibody responses as compared to s.c. immunisation with the same antigen. We further analysed the protective efficacy against virus challenge in a mouse model. A subunit antigen preparation of the A/New/Caledonia/20/99 strain was used for vaccination of NMRI mice with different combinations of adjuvants. The mice were challenged i.n. with 6.5 tissue culture infectious doses50 of homologous virus and sacrificed 3 days later. Since the virus is not lethal in mice, the protective efficacy was measured by quantitative, real-time PCR on pulmonary tissue, obtained at autopsy. The mice treated with only adjuvant and the group of naïve mice clearly had the highest mean viral RNA copy numbers (19.200 and 11.000, respectively). All vaccinated groups had significantly lower copy numbers, especially the mice that received the L3A i.n. (−median 120; i.n. L3B − median 2.200; and non-adjuvanted s.c. vaccination − median 2.600). Our findings prompt further investigations of the effect of the formulations in ferrets, monkeys and man.  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