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   1173篇
  免费   50篇
  国内免费   19篇
耳鼻咽喉   1篇
儿科学   5篇
妇产科学   3篇
基础医学   187篇
口腔科学   3篇
临床医学   17篇
内科学   96篇
皮肤病学   3篇
神经病学   8篇
特种医学   2篇
外科学   20篇
综合类   52篇
预防医学   730篇
眼科学   2篇
药学   90篇
中国医学   3篇
肿瘤学   20篇
  2023年   48篇
  2022年   64篇
  2021年   79篇
  2020年   66篇
  2019年   66篇
  2018年   57篇
  2017年   54篇
  2016年   51篇
  2015年   63篇
  2014年   61篇
  2013年   53篇
  2012年   62篇
  2011年   84篇
  2010年   76篇
  2009年   70篇
  2008年   43篇
  2007年   37篇
  2006年   26篇
  2005年   32篇
  2004年   25篇
  2003年   20篇
  2002年   16篇
  2001年   17篇
  2000年   13篇
  1999年   9篇
  1998年   6篇
  1997年   11篇
  1996年   4篇
  1995年   4篇
  1994年   4篇
  1993年   3篇
  1992年   2篇
  1991年   2篇
  1990年   1篇
  1989年   3篇
  1988年   2篇
  1987年   1篇
  1986年   3篇
  1985年   2篇
  1984年   1篇
  1982年   1篇
排序方式: 共有1242条查询结果,搜索用时 62 毫秒
51.
《Vaccine》2020,38(42):6524-6532
BackgroundFor the 2017–18 influenza season, A/Saitama/103/2014 (CEXP-002) (Saitama strain) was antigenically more similar to prior circulating strains than A/Hong Kong/4801/2014 (X-263) (Hong Kong strain) in a ferret model and was selected as the A(H3N2) vaccine virus strain in Japan. However, the Saitama strain grew poorly, and the Japanese government switched to the Hong Kong strain, raising public concerns of poor effectiveness. To enhance understanding of the correlation between antigenicity in experimental models and immunogenicity, as a surrogate measure of vaccine effectiveness, in the human population, we compared the immunogenicity of specially-prepared single dose monovalent influenza A(H3N2) vaccines containing the Saitama or the Hong Kong strain.MethodsA randomized controlled trial of 100 healthy adults aged 20–64 years (n = 50/group) was conducted. Virus neutralization assay was performed on sera from days 0 (pre-vaccination) and 21 (post-vaccination). Geometric mean titer (GMT), mean fold rise (MFR), seroconversion proportion (SCP), and seroprotection proportion (SPP) were calculated for vaccine strains and a representative circulating A(H3N2) virus strain (A/Osaka/188/2017).ResultsFor the Hong Kong strain, post-vaccination GMT was significantly higher in the Hong Kong vaccine recipients (1:546 vs 1:260, p < 0.01), but MFR, SCP, and SPP were similar for both vaccine groups. For the Saitama strain, post-vaccination GMT (1:116 vs 1:61, p = 0.01) and SPP (86% vs 68%, p = 0.03) were significantly higher in the Hong Kong vaccine recipients, but MFR and SCP were similar for both vaccine groups. Against A/Osaka/188/2017, post-vaccination GMT and MFR were similar in both vaccine groups, but SCP (32% vs 4%, p < 0.01) and SPP (28% vs. 6%, p < 0.01) were significantly higher in the Hong Kong vaccine recipients.ConclusionThe Hong Kong vaccine induced better or equivalent immunogenicity in comparison to the Saitama vaccine. Our trial showed that antigenic similarity in experimental models does not necessarily correlate with immunogenicity in the human population.Clinical trial registration: UMIN000029293.  相似文献   
52.
It is now known that all biologic drugs, even those that are fully human, are immunogenic, that is, they have the ability to induce an immune response in the treated patient. Since the presence of antidrug antibodies may influence the levels and function of the drug in the body, this immune response can alter the efficacy of the biologic treatment and even its safety profile, depending on the mechanism of action (neutralizing or nonneutralizing) and/or an accelerated clearance of the drug. Immunogenicity is a dynamic factor that should be taken into account when prescribing biologic therapy in psoriasis, especially in the case of long-term treatment and when assessing secondary loss of response. An understanding of the immunogenicity of biologic therapies and how this can be managed is useful not only for optimizing the treatment strategy used with each drug, but also for designing predictive models of response and even for tailoring therapy on a case-by-case basis.  相似文献   
53.
The safety, tolerability and immunogenicity of an oral cholera vaccine (OCV) was assessed in adult Korean male through an open-label, non-comparative clinical study. Two doses of vaccine with an interval of 2 weeks were given to 20 healthy subjects. A total of 7 adverse events occurred in 6 subjects. However, no clinically significant change was observed in electrocardiograms, vital signs, physical examinations, and clinical laboratory tests. The immunogenicity of OCV was evaluated by serum vibriocidal assay where anti-Vibrio cholerae O1 and O139 antibodies were measured at day 0, 14, and 28 of vaccine administration. The antibody titers ranged from < 2.5-5,120 for V. cholerae O1 Inaba, < 2.5-10,240 for V. cholerae O1 Ogawa and < 2.5-480 for V. cholerae O139. In addition, the fold increase in antibody titers ranged from 1-4,096 for O1 Inaba, 1-8,192 for O1 Ogawa, and 1-384 for O139. The seroconversion rate was 95% and 45% for O1 and O139 antibodies, respectively. Our study clearly shows that administration of two doses of OCV at a 2 week-interval increases an appropriate level of antibody titer in the serum of healthy Korean adult males (Clinical Trial Number, NCT01707537).

Graphical Abstract

  相似文献   
54.
背景:异体软骨移植是治疗关节软骨缺损主要手段,寻找软骨组织保存方法来降低移植软骨的免疫原性已成为临床上关键性的技术问题。 目的:比较慢速梯度降温法、玻璃化法与60Co射线照射+梯度降温法对同种异体骨软骨移植物免疫原性的影响。 方法:将关节软骨块随机分为4组:新鲜组不采取任何措施;慢速梯度降温组给予程序降温法保存关节软骨;玻璃化组利用玻璃化溶液处理后保存;60Co射线照射+梯度降温组给予60Co射线照射后,再按程序降温法保存关节软骨。保存8,15,30,60 d后关节软骨块经细胞培养及扩增后制备成细胞悬液。流式细胞仪检测关节软骨细胞表面主要组织相容性复合体Ⅰ,Ⅱ抗原表达率。 结果与结论:经过保存后,慢速梯度降温组、玻璃化组和60Co射线照射+梯度降温组细胞表面的主要组织相容性复合体Ⅰ和Ⅱ抗原表达率有大幅下降,与新鲜组相比有显著性差异,但前3组间没有显著性差异。各保存组主要组织相容性复合体Ⅰ类抗原和主要组织相容性复合体Ⅱ类抗原表达率均随着时间的推移下降,并且在30 d时3种不同保存方法保存的软骨细胞表面主要组织相容性复合体表达率就降低到最低。预示着经保存处理的关节软骨可能会提高同种异体骨软骨移植手术的成功率。  相似文献   
55.
Patients with malignancies are considered to be at increased risk of acquiring influenza. Because of higher complication and case fatality rates, preventive measures such as vaccination are of great interest. The objective of this study was to assess the acceptability, tolerability and immunogenicity of an adjuvant-free whole-virion pandemic influenza A (H1N1) vaccine in cancer patients with ongoing anticancer treatment during a ‘pandemic situation’. Adult patients with hematologic malignancies or solid tumors and concurrent cytotoxic, targeted, and/or hormone therapy were recruited during the influenza A (H1N1) pandemic in 2009/2010 and were offered free vaccine. Antibody titers were measured using virus-specific hemagglutination inhibition assay and ELISA. Among 285 patients with solid tumors who were offered vaccination during their therapy, 260 (91.2%) declined and 25 (8.8%) accepted. Seventeen patients with hematologic malignancies were also vaccinated during therapy; 23 healthy individuals served as a control group. When measured using hemagglutination-inhibition assays, rates of seroprotection, seroconversion, and geometric mean titer ratios after the second vaccination were 96%, 70%, and 4.1 respectively among the healthy individuals, 90%, 52%, and 4.3 among patients with solid tumors, and 67%, 13%, and 1.5 among patients with hematologic malignancies during therapy (P < 0.05). When measured using ELISA, seropositivity differed significantly among the three groups after the second vaccination: healthy individuals 74%, patients with solid tumors 57%, those with hematologic malignancies 13% (P < 0.001). The vaccine was well tolerated. Our results demonstrate a low uptake of the well tolerated adjuvant-free influenza A (H1N1) vaccine by cancer patients receiving anticancer treatment during the pandemic of 2009/2010. Among the vaccinated patients, the immune response was weaker than that in healthy individuals. The immune response in patients with hematological malignancies was low. Two doses of vaccine are needed in these immunosuppressed patients.  相似文献   
56.
57.

Background

We hypothesized that low dose intradermal vaccination of the trivalent influenza vaccine (TIV) delivered by the MicronJet600™ (NanoPass Technologies, Israel) would be non-inferior to the full dose intramuscular and mid dose Intanza® vaccination in the elderly and the chronically ill adults.

Methods

We performed a prospective randomized trial on elderly and chronically ill adults. Subjects were randomly assigned into 4 groups. Groups ID3 and ID9 received reduced dose ID TIV (3 μg and 9 μg of hemagglutinin (HA) per strain respectively) delivered by MicronJet600™ (NanoPass Technologies, Israel). Group INT9 received reduced dose ID TIV (9 μg) delivered by Becton Dickinson's Soluvia™ device (Intanza®9, Sanofi-Pasteur, France). Control group IM15 received a full dose IM TIV (15 μg). We measured antibody titers by hemagglutination inhibition (HAI) and microneutralization (MN) assays at baseline and day 21.

Results

Baseline characteristics for all groups were similar (group and sample sizes: ID3 = 63; ID9 = 68; INT9 = 65; and IM15 = 66). At day 21 post vaccination, the GMT ratio and the seroconversion rates difference for all three strains of the ID vaccine groups were non-inferior to the IM vaccine group. The seroconversion rate, seroprotection rate, and the GMT of the H1N1 strains by HAI and MN assays were significantly higher in the ID groups compared with the full dose IM vaccine group. The seroconversion rates of the H3N2 strain by HAI assay were also significantly higher in the ID groups when compared with the full dose IM group. Direct comparison among the three ID groups showed no significant differences. No serious adverse events related to vaccination were reported.

Conclusion

Dose-sparing ID TIV can overcome reduced immunogenicity of the H1N1 strain, and according to some measures, for the H3N2 strain. At risk subjects indicated for the TIV should be considered for intradermal immunization to compensate for reduced immunogenicity.  相似文献   
58.

Background

Concern arose in 2010 that reactogenicity, particularly febrile seizures, to influenza A/H1N1-containing 2010–2011 trivalent seasonal inactivated influenza vaccine (TIV) could occur in young children who had been previously immunized and/or infected with the pandemic strain. We conducted a pre-season study of 2010–2011 TIV safety and immunogenicity in children 12–59 months of age to inform public health decision making.

Methods

Children immunized with 1 or 2 doses of the pandemic vaccine, with or without the 2009–10 TIV, received 1 or 2 doses of 2010–11 TIV in an observational, multicentre Canadian study. Standard safety monitoring was enhanced by a telephone call at ∼24 h post-TIV when adverse events were expected to peak. Summary safety reports were rapidly reported to public health before the launch of public programs. TIV immunogenicity was assessed day 0, and 21 days after final vaccination. Clinical Trials Registration NCT01180621.

Results

Among 207 children, a general adverse event was reported by 60.9% of children post-dose one and by 58.3% post-dose two. Only severe fever (>38.5 °C) was more common in two-dose compared to one dose recipients (16.7%, n = 4 v. 1.0%, n = 2). At baseline 99.0% of participants had A/H1N1 hemagglutinin inhibition (HAI) titers ≥10, and 85.5% had a protective titer of ≥40 (95% CI 80.0, 90.0). Baseline geometric mean titers (GMT) were higher in recipients of a 2-dose schedule of pandemic vaccine compared to one-dose recipients: 153.1 (95% CI 126.2, 185.7) v. 78.8 ((58.1, 106.8, p < 0.001). At 21 days, all regulatory criteria for influenza vaccine immunogenicity were exceeded for A/H1N1 and H3N2, but responses to the B antigen were poor. No correlations between reactogenicity and either baseline high influenza titers or serologic response to revaccination were evident.

Conclusions

Infants and toddlers who received AS03-adjuvanted A/H1N1 2009 vaccine up to 11 months earlier retained high titers in the subsequent season but re-exposure to A/H1N1 2009 antigen in TIV resulted in no unusual adverse effects and 100% were sero-protected for A/H1N1 after receipt of the 2010–11 TIV.  相似文献   
59.
A worldwide vaccination campaign against the 2009 pandemic influenza A (H1N1) virus was launched among high-risk subjects, including hemodialysis patients. The long-term immunogenicity of an influenza vaccine has not been investigated in hemodialysis patients. This study aimed to (1) assess the long-term immunogenicity of a monovalent non-adjuvanted influenza A (H1N1) vaccine in hemodialysis patients and (2) determine the safety of this vaccine. We conducted a prospective cohort study of 44 hemodialysis patients and 149 healthy controls in 2010. All of the participants received a single dose of the monovalent non-adjuvanted 2009 influenza A (H1N1) vaccine. The level of antibodies was measured at baseline and at 4 and 24 weeks post-vaccination using a hemagglutination inhibition assay. The outcomes were the percentages of participants who achieved seroconversion and seroprotection (titer ≥1:40) 4 and 24 weeks after vaccination. At 4 weeks post-vaccination, seroconversion was observed in 17 (38.6%) of the hemodialysis patients and 94 (63.1%) of the controls (P = 0.056), and protective titers were obtained in 22 (50%) of the hemodialysis patients and 100 (67.1%) of the controls (P = 0.426). At 24 weeks post-vaccination, immunogenicity decreased in both the hemodialysis patients and the controls, but there were no significant differences between the hemodialysis patients and the controls in the seroconversion rate (27.3% versus 36.9%, P = 0.526) or the seroprotection rate (38.6% versus 48.3%, P = 0.996). No differences in adverse events were observed between the hemodialysis patients and the controls. In summary, the 2009 influenza A (H1N1) vaccine elicits a similar immune response in both hemodialysis patients and healthy controls, but immunity declines 24 weeks after vaccination in both groups. Hemodialysis patients should at least be vaccinated annually against the influenza virus.  相似文献   
60.
Lu CL  Hung CC  Chuang YC  Liu WC  Su CT  Hsiao CF  Tseng YT  Su YC  Chang SF  Chang SY  Chang SC 《Vaccine》2012,30(24):3526-3533

Background

Vaccination with 7-valent pneumococcal conjugate vaccine (PCV) has been shown to decrease the incidence of recurrent invasive pneumococcal disease among HIV-infected adults in Africa. Longitudinal follow-up studies of serologic responses to different doses of 7-valent PCV are rarely performed in HIV-infected adult patients receiving combination antiretroviral therapy (cART).

Methods

From October 2008 to June 2010, 115 CD4-matched pairs of HIV-infected patients aged ≥20 years who had no prior pneumococcal vaccination received one or two doses of 7-valent PCV. Anticapsular antibodies against 4 serotypes (6B, 14, 19F, and 23F) were examined at the 12th, 24th, 36th, and 48th week following vaccination. Significant antibody responses were defined as ≥2-fold increase in the IgG level plus a post-vaccination antibody level ≥1000 ng/ml.

Results

The most common reported adverse effects were injection site soreness (19.3%) and pain (4.8%). Significant antibody response rate was highest for serotype 14, followed by 23F, 19F, and 6B in all of the four time points examined. At week 48, patients who received two doses of 7-valent PCV had a significantly higher response rate to serotype 6B (P = 0.03) and 23F (P = 0.01) than those who received one dose; moreover, the former group also had a higher response rate to at least one (P = 0.03) and two serotypes (P = 0.02) in intention-to-treat analysis than the latter group.

Conclusions

HIV-infected adult patients on cART who received two doses of 7-valent PCV achieved better serological responses to at least one serotype than those who received one dose during the 48 weeks of follow-up.  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