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1.
Profound reductions in cortical acetylcholine levels together with degeneration of cholinergic neurons in the basal forebrain have been reported in patients with Alzheimer's disease. A similar loss of the cholinergic neurons of the basal forebrain and impairment of learning and memory occur in animals injected with a nerve growth factor-diphtheria toxin conjugate, suggesting that this animal model is suitable to analyze cholinergic roles on learning and memory processes, and also the pathogenesis of Alzheimer's disease. In addition, animal models constructed by electrolytic or neurotoxic lesioning of the basal magnocellular nucleus, and models made by transgenetic technology were described. 相似文献
2.
H. J. Schmitt F. Zepp S. Müschenborn G. Sümenicht A. Schuind K. Beutel M. Knuf H. L. Bock H. Bogaerts R. Clemens 《European journal of pediatrics》1998,157(3):208-214
With an increasing number of new vaccines available for routine childhood immunization, combination vaccines are needed in
order to maintain or achieve a high compliance with recommended immunization programmes. In a prospective, randomized, comparative,
multi-centre study, 822 healthy infants were enrolled to receive three doses of either a candidate or a commercially available
Haemophilus influenzae type b (Hib) vaccine concomitantly with diphtheria-, tetanus- acellular pertussis (DTaP) vaccine. Study subjects were randomly
allocated to one of the following groups: (1) separate, or (2) mixed injection of DTaP and candidate Hib vaccine, or (3) separate
injection of DTaP and commercial Hib vaccine. One year later the first 189 study subjects received either separate or mixed
injections of the same Hib and DTaP vaccines as booster doses. Evaluation of reactogenicity was based on diary cards completed
by parents. Immunogenicity was documented by measuring IgG antibody concentrations in serum samples taken before and 4 weeks
after primary and booster vaccination. No serious adverse events occurred and most local and systemic reactions were mild
to moderate. Booster doses were more reactogenic than primary doses with all groups. Antibody concentrations against pertussis
antigens were similar to those seen with DTaP alone. All but one subject had protective antibody concentrations against diphtheria
and tetanus. Primary immune response to the Hib vaccine was significantly lower in the group receiving the mixed Hib-DTaP
vaccine, however, ≥95% of vaccinees had anti-Hib antibody concentrations ≥0.15 μg/ml and there was a marked booster response
(>100-fold) in all groups.
Conclusions Mixing DTaP and Hib vaccines for primary immunization caused a decrease in anti-Hib antibody response, although after primary
immunization as after booster doses, all subjects showed antibody concentrations considered to be protective for invasive
Hib disease. Mixing of the vaccines did not result in increased reactogenicity.
Received: 13 June 1997 / Accepted in revised form: 4 September 1997 相似文献
3.
靶向DF3的白喉毒素A链基因对乳腺癌细胞的杀伤作用 总被引:2,自引:1,他引:2
目的探讨白喉毒素A链(DTA)基因在DF3/MUC1启动子调控下的杀伤作用。方法构建含人乳腺癌DF3启动子和白喉毒素A链基因的表达载体pGL3-DF3-DTA,转染DF3阳性的乳癌细胞MCF-7,逆转录-聚合酶链反应(RT-PCR)检测DTA基因的表达;噻唑蓝(MTT)比色法检测细胞生长活性;免疫组织化学法和流式细胞术检测细胞凋亡。结果酶切和测序表明获得了与预期结果相一致的pGL3-DF3-DTA真核表达载体。转染MCF-7细胞后,RT-PCR检测到了249 bp的DTA mRNA片段。与对照组比较,转染pGL3-DF3-DTA的MCF-7细胞生长受到了抑制,流式细胞术检测到的凋亡率达39.43%,而对照组仅有0.28%。结论pGL3-DF3-DTA可对DF3阳性的乳癌细胞产生特异性的杀伤,对乳腺癌的基因治疗有潜在的应用价值。 相似文献
4.
《The British journal of oral & maxillofacial surgery》2020,58(3):358-360
Diphtheria is an infectious disease caused by Corynebacterium diphtheriae, and is generally characterised by proliferation of the bacteria in the upper respiratory tract, formation of a pseudomembrane, and systemic diffusion of the diphtheria toxin throughout the body. We present the case of a young man with pseudomembranous plaques on the tongue and floor of the mouth, who received systemic and locoregional medical treatment, with a satisfactory outcome after 14 days. 相似文献
5.
Henrik Aggerbeck Bent Nørgaard-Pedersen Iver Heron 《Journal of immunological methods》1996,190(2):171-183
A dual, double antigen, time-resolved fluorescence immunoassay (DELFIA) for the simultaneous detection and quantitation of diphtheria (D) and tetanus (T) antibodies in sera has been developed. In the double antigen format one arm of the antibody binds to antigen coated microtitre wells and the other arm binds to labelled antigen to provide a fluorescent signal. This assay was found to be functionally specific for IgG antibodies and showed a good correlation with established toxin neutralization assays. Furthermore, the double antigen set-up was species independent, permitting the direct use of existing international references of animal origin to measure protective antibody levels in humans in international units (IU/ml). The detection limit corresponded to 0.0003 IU/ml with Eu3+-labelled toxoids and to 0.0035 IU/ml using Sm3+-labelled toxoids. The assay was fast with a high capacity making it a suitable method for serological surveillance studies. 相似文献
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9.
Vergara R Tregnaghi M Ussher J Navarro S Rüttimann R Potin M Wolter J Schuerman L 《European journal of pediatrics》2005,164(6):377-382
High rates of pertussis disease in adolescents suggest that additional boosting against pertussis would be beneficial. A combined acellular-pertussis-containing booster vaccine (dTpa-IPV; Boostrix Polio, n =440) was compared to separately administered dTpa (Boostrix) and inactivated polio virus (IPV; Imovax Polio®, n =219), and to DTPa-IPV (Infanrix IPV, n =111) vaccine in a partially blind, randomised controlled trial in 10–14 year olds. One month after vaccination, seroprotection/seropositivity rates for all antigens were similar for all groups. Although pertussis and diphtheria antibody geometric mean antibody concentrations were higher after DTPa-IPV, all subjects had protective antibodies against diphtheria, tetanus and polio, and at least 97% had a vaccine response to pertussis antigens. Reactogenicity of dTpa-IPV was comparable to dTpa + IPV, but dTpa-IPV was generally better tolerated than DTPa-IPV. Conclusion:The combined reduced-antigen-content-diphtheria-tetanus-acellular-pertussis and IPV vaccine is immunogenic and well tolerated when administered to adolescents and could be used to improve the control of pertussis disease in this age group. 相似文献
10.
目的 构建白喉毒素N端 389个氨基酸 (DT389)与人白细胞介素 13(hIL 13)的融合蛋白DT389 hIL 13,并检测其生物学活性。方法 通过聚合酶链反应 (PCR)扩增得到hIL 13的cDNA ,将序列正确的hIL 13及DT389的cDNA片段串联插入表达载体pET30a ,构建表达质粒pET30a/DT389 hIL 13,并对表达产物进行鉴定及初步纯化。该融合蛋白加入培养的U2 51胶质细胞中 ,应用MTS方法检测其对多型性胶质母细胞瘤细胞的杀伤作用。结果 得到序列正确的融合蛋白DT389 hIL 13的表达质粒pET30a/DT389 hIL 13,该质粒在大肠杆菌成功表达 ,经初步纯化后 ,十二烷基磺酸钠 聚丙烯酰胺 (SDS PAGE)凝胶电泳及Western印迹分析表明 ,该融合蛋白对白喉毒素多克隆抗体及hIL 13多克隆抗体都有很好的免疫反应性 ,相对分子质量约为 5 5 0 0 0 ;进一步活性检测发现 ,该融合蛋白对多型性胶质母细胞瘤细胞系U2 5 1的生长有较强的抑制作用 ,且作用存在剂量相关性 ,其半数抑制浓度(IC50 )约为 5× 10 -11mol/L。结论 成功构建了融合蛋白DT389 hIL 13的表达质粒 ,在细胞水平对表达产物进行了初步的活性检测 ,为进一步研制特异性的抗胶质瘤药物打下了基础。 相似文献