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41.
Doris Freißmuth Alexander Hiltgartner Christiane Stahl‐Hennig Dietmar Fuchs Klara Tenner‐Racz Paul Racz Klaus Überla Alexander Strasak Manfred P. Dierich Heribert Stoiber Barbara Falkensammer 《Journal of medical primatology》2010,39(2):97-111
Background To determine the correlation between protection and humoral immune response against simian immunodeficiency virus (SIVmac251), 11 macaques were immunized with live‐attenuated SIVmac239Δnef either intravenously or via the tonsils and exposed to SIVmac251 after either 6 or 15 months along with unvaccinated controls. Results Independent of the route of vaccine application, viremia was significantly reduced in vaccinees compared with controls 2 weeks post‐challenge. Concomitantly, viremia correlated inversely with SIV‐specific IgG, complement‐mediated lysis and neutralizing antibodies and these parameters seemed to contribute to reduced viremia. During chronic infection, six monkeys controlled viremia in the circulation (two or fewer infectious units per 106 PBMCs) and showed no signs of trapping in lymphatic tissues (Appendix S1). Conclusions As no significant differences were observed throughout the study, with respect to the humoral immune response and viremia control, between the two vaccinated cohorts, mucosal immunization strategies are recommended due to more simplified application. 相似文献
42.
HAKAN GÜR 《Biological journal of the Linnean Society. Linnean Society of London》2010,100(3):695-710
A phylogenetic comparative analysis of geographic variation in body size of an obligately hibernating marmotine species (Anatolian ground squirrels, Spermophilus xanthoprymnus) is presented in relation to environmental variables that pertain to four principal hypotheses (heat conservation, heat dissipation, primary productivity, and seasonality hypotheses). Adult Anatolian ground squirrels (78 males and 90 females) were collected from ten geographic localities in Anatolia for use in morphometric analyses. First, the study tested whether significant variation in body size occurs over the geographic range of S. xanthoprymnus. Then, to understand the possible cause(s) of the observed pattern of geographic variation in body size of Anatolian ground squirrels, four hypotheses were tested, separately and simultaneously, using a phylogenetic comparative method. Overall, food availability (primary productivity hypothesis) and, especially in males, over‐winter fasting endurance (seasonality hypothesis) are likely the primary underlying mechanisms generating the observed pattern of increasing body size towards colder, more seasonal environments, with higher summer precipitation and productivity (or a Bergmannian size pattern). © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100 , 695–710. 相似文献
43.
FLORIAN WITZMANN HENNING SCHOLZ JOHANNES MÜLLER NIKOLAY KARDJILOV 《Zoological Journal of the Linnean Society》2010,160(2):302-340
Sculpture of dermal bones and their vascularization in basal tetrapods are closely connected. Ontogenetic data suggest that the large vessels that coursed to the superficial bone surface induced the formation of sculptural ridges and tubercles around their openings. Imprints show that the vessels continued on the bone surface and coursed within furrows or pits, where they were protected by the sculpture from mechanical damage. Dermal bone histology indicates a consolidation of the integument in basal tetrapods by strong, mineralized Sharpey's fibres in the sculptural ridges and tubercles, and by the presence of metaplastic tissue in several taxa. Because of the tight integration of bone and dermis, the large vessels were not able to spread over the sculptural elements, but instead had to pass interosseously. The diverse sculptural morphologies depend on the variation in height and width of the ‘nodal points’ and their connecting ridges, and in the size and shape of the enclosed cells and furrows. A principal component analysis (PCA) and discriminant function analysis (DFA) of 47 basal tetrapod taxa with 12 discrete characters shows that dermal sculpture is suited for distinguishing some main basal tetrapod lineages. Taxa that are interpreted as being largely aquatic have generally a more regular sculpture than presumably terrestrial ones. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 302–340. 相似文献
44.
A juvenile skull of Dysalotosaurus lettowvorbecki, a basal iguanodontian from the Middle Dinosaur Member (Kimmeridgian) of the Tendaguru Beds (Tanzania), is described and reconstructed in detail. Further preparation and computed tomography scans have uncovered additional and formerly unknown skull elements, especially of the lower jaw. The reconstruction of the skull reveals ontogenetic differences to earlier reconstructions, which were based on specimens of relatively older individuals. The most notable ontogenetic changes in Dysalotosaurus are a relative lengthening of the muzzle, a decrease in the relative size of the orbit, and a straightening of the posterior skull roof. Additionally, ontogenetic variations were found in many single elements of the skull, all of which reflect the three main tendencies described above. Furthermore, there might have been an ontogenetic change in the diet, from omnivorous juveniles to fully herbivorous adults. The results of this study will help to evaluate ontogenetic stages in other ornithopods, and will shed light on a crucial stage of ornithopod evolution that culminated in the highly specialized and diverse hadrosaurs of the Cretaceous. Many of the evolutionary changes seen in this lineage can be attributed to peramorphism, and probably reflect a perfection of the adaptation towards an obligatory herbivorous diet. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 366–396. 相似文献
45.
NIKOS T. PAPADOPOULOS JAMES R. CAREY PABLO LIEDO HANS‐GEORG MÜLLER DAMLA SENTÜRK 《Physiological Entomology》2009,34(3):238-245
Abstract. Aggressive behaviour occurring in intrasexual competition is an important trait for animal fitness. Although female intrasexual aggression is reported in several insect species, little is known about female competition and aggressive interactions in polygynous male lekking species. The interactions of female Mediterranean fruit flies, Ceratitis capitata (a male lekking species), with other females and mating pairs under laboratory conditions are investigated. Mature, unmated (virgin) females are aggressive against each other and against mating pairs, whereas immature females are not. Female aggression against other females decreases dramatically after mating; however, mated females maintain aggression against mating pairs. In addition, higher intrasexual aggression rates are observed for mature, virgin females than for virgin males of the same age. The results show that female aggressiveness is virginity related, suggesting female competition for mates. These findings have important implications for understanding the physiological aspects of a complex social behaviour such as aggression and should stimulate further research on female agonistic behaviour in male lekking mating systems. 相似文献
46.
【目的】通过筛选西伯利亚蝗Gomphocerus sibiricus卵滞育基因及代谢通路,初步明确西伯利亚蝗卵滞育分子机理。【方法】利用Illumina NovaSeq 6000测序平台对西伯利亚蝗早期发育(ES)、滞育(DS)和滞育后发育阶段(PS)的卵进行转录组测序;采用GO和KEGG富集分析并结合文献,预测滞育相关通路并聚类热图分析,筛选蝗卵滞育关联基因,并选取其中6个重要基因进行qRT-PCR验证。【结果】DSvs ES和PS vs DS两比较组分别富集到12 419和4 789个差异表达基因,且多上调表达;两比较组共表达差异基因为2 206个,主要与糖代谢、环境胁迫和生长发育相关。DS vs ES组富集最显著的GO条目为蛋白结合,PS vs DS组GO条目主要包含酶活性、细胞骨架构建及蛋白结合等过程。滞育关联基因主要集中在Wnt信号通路、胰岛素信号通路、细胞周期通路以及昆虫激素生物合成等通路。6个重要的滞育关联基因的表达量变化趋势与转录组数据结果基本一致。【结论】本研究初步明确了西伯利亚蝗卵滞育调控的重要代谢途径,并筛选出20个滞育关联基因,为后续深入研究该物种的适应机理奠定了基础。 相似文献
47.
Kuşçu Gökçe Ceren Gürel Çevik Buhur Aylin Oltulu Fatih Akman Levent Köse Timur Yavaşoğlu Nefise Ülkü Karabay Yavaşoğlu Altuğ 《Molecular biology reports》2022,49(3):1721-1729
Molecular Biology Reports - Polycystic ovary syndrome (PCOS) is a metabolic disease that causes infertility due to anovulation in women in reproductive age. It is known that clomiphene citrate (CC)... 相似文献
48.
Üstündağ Fümet Duygu Ünal İsmail Üstündağ Ünsal Veli Cansız Derya Beler Merih Karagöz Atakan Kara Subaşat Hülya Alturfan A. Ata Mega Tiber Pınar Emekli-Alturfan Ebru 《Neurochemical research》2022,47(6):1553-1564
Neurochemical Research - Parkinson’s disease (PD) is one of the most common forms of neurodegenerative diseases and research on potential therapeutic agents for PD continues. Rotenone is a... 相似文献
49.
50.
Controls of the quantum yield and saturation light of isoprene emission in different‐aged aspen leaves 下载免费PDF全文
Leaf age alters the balance between the use of end‐product of plastidic isoprenoid synthesis pathway, dimethylallyl diphosphate (DMADP), in prenyltransferase reactions leading to synthesis of pigments of photosynthetic machinery and in isoprene synthesis, but the implications of such changes on environmental responses of isoprene emission have not been studied. Because under light‐limited conditions, isoprene emission rate is controlled by DMADP pool size (SDMADP), shifts in the share of different processes are expected to particularly strongly alter the light dependency of isoprene emission. We examined light responses of isoprene emission in young fully expanded, mature and old non‐senescent leaves of hybrid aspen (Populus tremula x P. tremuloides) and estimated in vivo SDMADP and isoprene synthase activity from post‐illumination isoprene release. Isoprene emission capacity was 1.5‐fold larger in mature than in young and old leaves. The initial quantum yield of isoprene emission (αI) increased by 2.5‐fold with increasing leaf age primarily as the result of increasing SDMADP. The saturating light intensity (QI90) decreased by 2.3‐fold with increasing leaf age, and this mainly reflected limited light‐dependent increase of SDMADP possibly due to feedback inhibition by DMADP. These major age‐dependent changes in the shape of the light response need consideration in modelling canopy isoprene emission. 相似文献