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81.
Victor v. Janka 《Plant Systematics and Evolution》1868,18(4):128-128
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82.
Victor von Janka 《Plant Systematics and Evolution》1864,14(5):133-139
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83.
Viktor v. Janka 《Plant Systematics and Evolution》1860,10(2):35-37
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84.
V. v. Janka 《Plant Systematics and Evolution》1864,14(11):354-355
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85.
Victor v. Janka 《Plant Systematics and Evolution》1870,20(4):111-114
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86.
Jeanette C. Reece Liyen Loh Sheilajen Alcantara Caroline S. Fernandez John Stambas Amy Sexton Robert De Rose Janka Petravic Miles P. Davenport Stephen J. Kent 《PloS one》2010,5(9)
Successful vaccination against HIV should limit viral replication sufficiently to prevent the emergence of viral immune escape mutations. Broadly directed immunity is likely to be required to limit opportunities for immune escape variants to flourish. We studied the emergence of an SIV Gag cytotoxic T cell immune escape variant in pigtail macaques expressing the Mane-A*10 MHC I allele using a quantitative RT-PCR to measure viral loads of escape and wild type variants. Animals receiving whole Gag expressing vaccines completely controlled an SIVmac251 challenge, had broader CTL responses and exhibited minimal CTL escape. In contrast, animals vaccinated with only a single CTL epitope and challenged with the same SIVmac251 stock had high levels of viral replication and rapid CTL escape. Unvaccinated naïve animals exhibited a slower emergence of immune escape variants. Thus narrowly directed vaccination against a single epitope resulted in rapid immune escape and viral levels equivalent to that of naïve unvaccinated animals. These results emphasize the importance of inducing broadly directed HIV-specific immunity that effectively quashes early viral replication and limits the generation of immune escape variants. This has important implications for the selection of HIV vaccines for expanded human trials. 相似文献
87.
88.
M. von Balthazar J. Schönenberger W. S. Alverson H. Janka C. Bayer D. A. Baum 《Plant Systematics and Evolution》2006,260(2-4):171-197
Androecial development and structure as well as floral vasculature of six selected species of Bombacoideae and of several
smaller lineages of the Malvatheca clade (Malvaceae s.l.) were studied. All studied taxa share a similar pattern of androecial
development: initially, five antepetalous/antetepalous and five alternipetalous/alternitepalous primary androecial primordia
develop on a ring wall. Two elongate secondary androecial primordia form on each antepetalous/antetepalous sector. At anthesis
the androecium consists of an androecial tube crowned by five androecial lobes. Each of these lobes is the developmental product
of an alternipetalous/alternitepalous primary androecial primordium and its two neighbouring antepetalous/antetepalous secondary
androecial primordia. The elongate, sessile androecial units are positioned along the lateral margins of the androecial lobes
and in the distal part of the androecial tube. Seen in the light of the most recent studies of floral development and phylogeny
of the Malvaceae and the Malvales as a whole, our data indicate that i) elongate, sessile androecial units are ancestral in
the Malvatheca clade, that ii) an obdiplostemonous floral ground plan is a synapomorphy for the Malvaceae, and that iii) diplostemony
is most likely ancestral in the Malvales. 相似文献
89.
Ming Liang Chan Janka Petravic Alexandra M. Ortiz Jessica Engram Mirko Paiardini Deborah Cromer Guido Silvestri Miles P. Davenport 《Proceedings. Biological sciences / The Royal Society》2010,277(1701):3773-3781
Human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) infections result in chronic virus replication and progressive depletion of CD4+ T cells, leading to immunodeficiency and death. In contrast, ‘natural hosts’ of SIV experience persistent infection with high virus replication but no severe CD4+ T cell depletion, and remain AIDS-free. One important difference between pathogenic and non-pathogenic infections is the level of activation and proliferation of CD4+ T cells. We analysed the relationship between CD4+ T cell number and proliferation in HIV, pathogenic SIV in macaques, and non-pathogenic SIV in sooty mangabeys (SMs) and mandrills. We found that CD4+ T cell proliferation was negatively correlated with CD4+ T cell number, suggesting that animals respond to the loss of CD4+ T cells by increasing the proliferation of remaining cells. However, the level of proliferation seen in pathogenic infections (SIV in rhesus macaques and HIV) was much greater than in non-pathogenic infections (SMs and mandrills). We then used a modelling approach to understand how the host proliferative response to CD4+ T cell depletion may impact the outcome of infection. This modelling demonstrates that the rapid proliferation of CD4+ T cells in humans and macaques associated with low CD4+ T cell levels can act to ‘fuel the fire’ of infection by providing more proliferating cells for infection. Natural host species, on the other hand, have limited proliferation of CD4+ T cells at low CD4+ T cell levels, which allows them to restrict the number of proliferating cells susceptible to infection. 相似文献
90.
Csongor I. Vgsi Attila Fülp Gergely Osvth Pter L. Pap Janka Pnzes Zoltn Benk dm Z. Lendvai Zoltn Barta 《Proceedings. Biological sciences / The Royal Society》2021,288(1943)
Social groups often consist of diverse phenotypes, including personality types, and this diversity is known to affect the functioning of the group as a whole. Social selection theory proposes that group composition (i.e. social environment) also influences the performance of individual group members. However, the effect of group behavioural composition on group members remains largely unexplored, and it is still contentious whether individuals benefit more in a social environment with homogeneous or diverse behavioural composition. We experimentally formed groups of house sparrows Passer domesticus with high and low diversity of personality (exploratory behaviour), and found that their physiological state (body condition, physiological stress and oxidative damage) improved with increasing group-level diversity of personality. These findings demonstrate that group personality composition affects the condition of group members and individuals benefit from social heterosis (i.e. associating with a diverse set of behavioural types). This aspect of the social life can play a key role in affiliation rules of social animals and might explain the evolutionary coexistence of different personalities in nature. 相似文献