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1.
Seasonal and pandemic influenza remains a constant threat. While standard influenza vaccines have great utility, the need for improved vaccine technologies have been brought to light by the 2009 swine flu pandemic, highly pathogenic avian influenza infections, and the most recent early and widespread influenza activity. Species C adenoviruses based on serotype 5 (AD5) are potent vehicles for gene-based vaccination. While potent, most humans are already immune to this virus. In this study, low seroprevalent species D adenoviruses Ad26, 28, and 48 were cloned and modified to express the influenza virus A/PR/8/34 hemagglutinin gene for vaccine studies. When studied in vivo, these species D Ad vectors performed quite differently as compared to species C Ad vectors depending on the route of immunization. By intramuscular injection, species D vaccines were markedly weaker than species C vaccines. In contrast, the species D vaccines were equally efficient as species C when delivered mucosally by the intranasal route. Intranasal adenovirus vaccine doses as low as 108 virus particles per mouse induced complete protection against a stringent lethal challenge dose of influenza. These data support translation of species D adenoviruses as mucosal vaccines and highlight the fundamental effects of differences in virus tropism on vaccine applications.  相似文献   

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为了比较不同来源乳腺特异表达载体的表达特性 ,将人溶菌酶 (hLYZ)cDNA分别克隆入自行构建的p2 0 5C3载体和国外引进的pBJ41和pBC1载体。重组载体p2 0 5C3LYZ、pBJLYZ和pBCLYZ分别用 2 5kDaPEI包裹后 ,通过尾静脉途径注射哺乳期小鼠。注射后 72h采集乳样 ,经微球菌溶解实验证明 ,3组小鼠乳汁中hLYZ的表达量分别为 87、69、60mg L ;从每组小鼠的 1 2种组织提取总RNA ,经Dotblotting检测证明 ,三种重组载体除在乳腺中表达外 ,p2 0 5C3LYZ还在小鼠的脾和肠、pBJLYZ在脾、pBCLYZ在脾和肾中具有一定的异位表达 ;在有hLYZmRNA转录的上述脏器中用微球菌溶解试验均可检测到hLYZ活性。这些实验结果表明 ,自行构建的乳腺特异表达载体的表达特性与从国外引进的表达载体无明显差别。  相似文献   

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Malignant tumors represent a major source of disability and account for more than one of five deaths in Western countries. Among the different cancers, melanoma harbors two distinctive features. First, its has long been recognized as an immunogenic tumor, and second, an unprecedented rise in incidence is currently observed, in face of few therapeutic options. Thus, melanoma represent an ideal target for a cancer immunotherapy program. To date, a number of immunodominant epitopes from tumor associated antigens (TAA) are used as cancer vaccines in clinical trials, in spite of an acknowledged rapid degradation in vivo and low immunogenicity. However, most of the immunotherapy trials reported so far do not achieve consistent clinical results. Hence, there is an urgent need for the development of a carrier system and strong adjuvants suitable for a TAA-based cancer immunotherapy. Liposomes and their further development as virosomes with added adjuvancy may address both these issues. We report here our experience in the tailoring of dedicated advanced liposomal vectors that were developed in the context of an upcoming immunotherapy clinical trial for melanoma.  相似文献   

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通过组织学观察与测量对网翅蝗科(直翅目:蝗总科)中3种蝗虫卵子发生各阶段进行比较和分析,3种蝗虫分别为:绿牧草蝗Omocestus viridulus(Linnaeus),素色异爪蝗Euchorthippus unicolor(Ikonn.)和条纹异爪蝗Euchorthippus vittatus Zheng。结果表明,在蝗虫卵子发生过程中,卵母细胞体积和形态变化显著,呈现指数增长模式;细胞核体积增长在发育初期增长显著,后期变化不显著;滤泡细胞体积和形态及数量呈现周期性变化规律;比较种间差异发现不同种蝗虫的卵子发生存在不同的发育进程。  相似文献   

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A comparison of vanadium-rich activity of three species fungi of Basidiomycetes, Ganoderma lucidum, Coprinus comatus, and Grifola frondosa, was studied. By fermentation and atomic absorption spectroscopy analysis, the biomass of G. lucidum and G. frondosa declined rapidly when the concentration of vanadium exceeded 0.3% but the biomass of C. comatus did not decline rapidly until the concentration of vanadium exceeded 0.4% and the content of vanadium accumulated in the mycelia was 3529.3 μg/g. After the mice were administered (intragastrically) with vanadium-rich C. comatus, the blood glucose of alloxan-induced hyperglycemic mice was decreased (p < 0.05) and the body weight of the alloxan-induced hyperglycemic mice was increased gradually. Thus, we selected C. comatus to absorb vanadium and chose 0.4% as the optimal concentration of vanadium for the pharmacological works.  相似文献   

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林蛙属3物种皮肤的组织结构比较   总被引:1,自引:0,他引:1  
利用石蜡切片和H.E染色技术,对蛙科(Ranidae)林蛙属(Rana)高原林蛙(R.kukunoris)、昭觉林蛙(R.chaochiaoensis)和峨眉林蛙(R.omeimontis)的皮肤组织结构进行了观察。应用SPSS 13.0统计软件,对皮肤的厚度、皮肤腺的相对数量和面积作了比较分析。3物种皮肤的基本结构相似,都由表皮和真皮组成。表皮是角质化的复层扁平上皮,由角质层、颗粒层、棘细胞层和生发层构成。真皮又分为疏松层和致密层,疏松层内分布有黏液腺、颗粒腺和脂腺3种类型的皮肤腺,黏液腺在体背和体腹皮肤内基本均匀分布,而颗粒腺主要以团块聚集形式散布在体背皮肤中。在高原林蛙皮肤中还发现了1种与以往描述不同的特殊嗜酸性腺体。皮肤厚度存在种间差异和部位差异。高原林蛙的表皮里有少量毛细血管和发达的色素细胞分布,真皮疏松层里有发达的腺体,这些可能是其对高海拔、低氧、低温和强紫外线辐射生活环境的适应策略。在峨眉林蛙和昭觉林蛙皮肤真皮的疏松层和致密层相邻处,发现有呈波浪条带状的、H.E染色呈蓝色的钙化层结构,体背部的钙化层比体腹部的发达。钙化层的功能可能包括防止体内水分散失、贮存钙离子、构成与体外环境进行物质交换的屏障等方面。  相似文献   

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云南昆明地区三种蛙皮肤显微结构的比较   总被引:3,自引:1,他引:2  
对昆明地区的多疣狭口蛙、昭觉林蛙及黑斑蛙的背腹皮肤切片的显微结构进行了观察和比较,尤其对它们皮肤腺体的类型和功能进行了比较分析.结果 表明:多疣狭口蛙皮肤比昭觉林蛙及黑斑蛙皮肤含有更多的腺体,尤其是颗粒腺比后两者含量更为丰富,并且在皮下存在许多腺体团,背腹皮肤较后者厚.昭觉林蛙皮肤较黑斑蛙的含有更多的颗粒腺和粘液腺.3种蛙的背部皮肤都含有色素细胞,而除了在多疣狭口蛙雌性腹部观察到少量色素细胞外,另两种蛙在腹部皮肤中均未见色素层.相比之下,昭觉林蛙和黑斑蛙皮肤结构较相似,两者同多疣狭口蛙在皮肤腺体分布及数量上差别较大,这也体现了三者不同的生态适应机制.  相似文献   

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为了解樟科植物雌雄异熟的繁育系统特点,对3种樟科植物阴香(Cinnamomum burmannii)、紫楠(Phoebe sheareri)和浙江楠(Phoebe chekiangensis)雌雄异熟花的开花动态进行了比较研究.结果表明,3种植物雌性功能期的开始时间、雌性功能期和雄性功能期的时间分配有差异.3种植物的主...  相似文献   

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采用快速瑞氏-姬姆萨(Wright's-Giemsa's)染色法对斑腿泛树蛙(Polypedates megacephalus)和沼水蛙(Hylarana guentheri)的外周血细胞进行观察,并与北部湾棱皮树蛙(Theloderma corticale)己有的数据进行了比较.结果显示,三种蛙的血细胞均由红细胞、白...  相似文献   

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Species Richness and Invasion Vectors: Sampling Techniques and Biases   总被引:2,自引:0,他引:2  
During a European Union Concerted Action study on species introductions, an intercalibration workshop on ship ballast water sampling techniques considered various phytoplankton and zooplankton sampling methods. For the first time, all the techniques presently in use worldwide were compared using a plankton tower as a model ballast tank spiked with the brine shrimp and oyster larvae while phytoplankton samples were taken simultaneously in the field (Helgoland Harbour, Germany). Three cone-shaped and 11 non-cone shaped plankton nets of different sizes and designs were employed. Net lengths varied from 50 to 300 cm, diameters 9.7–50 cm, and mesh sizes 10–100 μm. Three pumps, a Ruttner sampler, and a bucket previously used in ballast water sampling studies were also compared. This first assessment indicates that for sampling ballast water a wide range of techniques may be needed. Each method showed different results in efficiency and it is unlikely that any of the methods will sample all taxa. Although several methods proved to be valid elements of a hypothetical `tool box' of effective ship sampling techniques. The Ruttner water sampler and the pump P30 provide suitable means for the quantitative phytoplankton sampling, whereas other pumps prevailed during the qualitative trial. Pump P15 and cone-shaped nets were the best methods used for quantitative zooplankton sampling. It is recommended that a further exercise involving a wider range of taxa be examined in a larger series of mesocosms in conjunction with promising treatment measures for managing ballast water. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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湖北省直翅目三新种(直翅目)   总被引:3,自引:0,他引:3  
记述采自湖北省九宫山及武当山地区直翅目昆虫3新种,即橙股卵翅蝗Caryanda byrrhofemura,sp.nov.,九宫山澳汉蚱Austrohancokia jiugongshanensis,sp.nov.及幕阜山台蚱Formosatettix mufushanensis,sp.nov.。此外记述贺兰台蚱Formosatettix helanshanensis Zheng的雄性。  相似文献   

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3种番荔枝科植物花粉形态观察   总被引:1,自引:0,他引:1  
利用扫描电子显微镜对番荔枝科2属3种植物的干花粉形态进行了观察,旨在为番荔枝科植物花粉多样性及其演化关系提供形态学证据。观察结果显示,Asimina longifolia var.spatulata Kral、Asimina reticulate Shuttlew.ex Chapm.和Disepalum plagioneurum(Diels)D.M.Johnson 3种植物的花粉多为四合体,在Asimina reticulata内偶见二合体、三合体,Disepalum plagioneurum偶见多合体;四合体类型大多为偏菱形,A.reticulata和D.plagioneurum中偶见四角形;3种植物花粉表面纹饰分别为皱波状(rugulate)、微网状(microreticulate)和网状(reticulate)。花粉通过形成外壁短链接(short exine connections)或花粉联丝(pollen-connecting threads)的方式将四合体凝集成花粉块(pollinium),提高了单一传粉过程中卵细胞的受精几率。Asimina和Disepalum两属植物花粉在表面纹饰、四合体类型等方面都十分相似,支持两者在系统发育中亲缘关系较近的观点。  相似文献   

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报道了3种国产防己科植物的染色体数目。金线吊乌龟Stephania cepharantha Hayata为二倍体2n=22,部分居群的一些个体存在B染色体;轮环藤Cyclea racemosa Oliv.为二倍体2n=24;木防己CDcculus orbiculatus(L)DC为四倍体2n=4x=52.3个种的染色体基数分别为x=11,12,13。观察了木防己的小孢子母细胞减数分裂过程,其减数分裂过程正常,且花粉粒具较高活性。  相似文献   

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报道了中国兰科植物的三个新记录种,裂唇卷瓣兰(Bulbophyllum picturatum),长柄虾脊兰(Calan-the allizettei)和绿花毛兰(Eria lanigera)。裂唇卷瓣兰的中萼片全缘前部具一粒状附属物,唇瓣基部两侧具耳。长柄虾脊兰的中裂片非常小并具三条褶片。黄花毛兰的花黄绿色,唇瓣不裂。  相似文献   

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Three new Leuctra species, L. khroumiriensis sp. n., L. sartorii sp. n. and L. medjerdensis sp. n., from Tunisia, are described. They share a close morphological relationship with two other species of the hippopus group, L. occitana Despax and L. vaillanti Aubert, which are redescribed. L. occitana is redescribed from material collected in Southern Spain, and L. vaillanti from Moroccan and Tunisian material, constituting the first record for Tunisia.  相似文献   

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记述瘿螨科3新种:紫珠瘤瘿螨Aceria callicarpae,sp.nov.,寄主为大叶紫珠;甜茶叶刺瘿螨Phyllocoptes suavissimi,sp.nov.,寄主为甜茶;以及黄瑞木畸瘿螨Abacarus adinandrae sp.nov.,寄主为亮叶黄瑞木。  相似文献   

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Three new Mexican species ofVernonia,V. macphersonii,V. pugana andV. tequilana, are described.  相似文献   

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