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601.
Arno G. Wouters 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2003,34(4):633-668
I argue that there are at least four different ways in which the term ‘function’ is used in connection with the study of living organisms, namely: (1) function as (mere) activity, (2) function as biological role, (3) function as biological advantage, and (4) function as selected effect. Notion (1) refers to what an item does by itself; (2) refers to the contribution of an item or activity to a complex activity or capacity of an organism; (3) refers to the value for the organism of an item having a certain character rather than another; (4) refers to the way in which a trait acquired and has maintained its current share in the population. The recognition of a separate notion of function as biological advantage solves the problem of the indeterminate reference situation that has been raised against a counterfactual analysis of function, and emphasizes the importance of counterfactual comparison in the explanatory practice of organismal biology. This reveals a neglected problem in the philosophy of biology, namely that of accounting for the insights provided by counterfactual comparison. 相似文献
602.
de Oliveira Carolina Alcantara Mansano Vidal de Freitas Teixeira Simone Pádua Brandes Arno Fritz das Neves Baratto Leopoldo Clemente Leitão Suzana Guimarães Santana Michele Nunes Rodrigues Igor Almeida Paulino Juliana Villela 《Journal of plant research》2021,134(1):127-139
Journal of Plant Research - The Swartzia species are commonly known as bloodwood due to the red exudate released from the stem after injury. This exudate has aroused great... 相似文献
603.
Lygia Gago Miolaro Antonio Natal Gonçalves João Carlos Teixeira Mendes Rildo Moreira e Moreira Arno Brune Paulo Henrique Müller da Silva 《Biological invasions》2017,19(6):1733-1737
Eucalypt species are widely used around the world due to their high productivity; however there are some concerns about the invasiveness capacity of eucalypts. We assessed old seed production areas of commercial eucalypt species thought of being at risk of invasion in two places in Southeastern Brazil (Anhembi: lat: 22°28′S; long: 48°04′W; and Itatinga lat: 23°02′S; long: 48°38′W). We observed differences between places and among species. The species with the higher number of plantation stands and higher demand for seeds had more regeneration. Regeneration was recorded in only a few plots and trees and seedlings were found very close to the eucalypt stand, in sites where waste from seed harvesting is dumped. For spontaneous regeneration of eucalypts to occur there is a need for favorable environmental conditions. Such conditions may be created by human activities or natural events which suppress competition from vegetation. 相似文献
604.
605.
Fran?ois Curtin Hervé Perron Arno Kromminga Hervé Porchet Alois B Lang 《MABS-AUSTIN》2015,7(1):265-275
Monoclonal antibodies (mAbs) play an increasing important role in the therapeutic armamentarium against multiple sclerosis (MS), an inflammatory and degenerative disorder of the central nervous system. Most of the mAbs currently developed for MS are immunomodulators blocking the inflammatory immune process. In contrast with mAbs targeting immune function, GNbAC1, a humanized IgG4 mAb, targets the multiple sclerosis associated retrovirus envelope (MSRV-Env) protein, an upstream factor in the pathophysiology of MS. MSRV-Env protein is of endogenous retroviral origin, expressed in MS brain lesions, and it is pro-inflammatory and toxic to the remyelination process, by preventing the differentiation of oligodendrocyte precursor cells. We present the preclinical and early clinical development results of GNbAC1. The specificity of GNbAC1 for its endogenous retroviral target is described. Efficacy of different mAb versions of GNbAC1 were assessed in MSRV-Env induced experimental allergic encephalitis (EAE), an animal model of MS. Because the target MSRV-Env is not expressed in animals, no relevant animal model exists for a proper in vivo toxicological program. An off-target 2-week toxicity study in mice was thus performed, and it showed an absence of safety risk. Additional in vitro analyses showed an absence of complement or antibody-dependent cytotoxicity as well as a low level of cross-reactivity to human tissues. The first-in-man clinical study in 33 healthy subjects and a long-term clinical study in 10 MS patients showed that GNbAC1 is well tolerated in humans without induction of immunogenicity and that it induces a pharmacodynamic response on MSRV biomarkers. These initial results suggest that the mAb GNbAC1 could be a safe long-term treatment for patients with MS with a unique therapeutic mechanism of action. 相似文献
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607.
Christopher J. Alteri Stephanie D. Himpsl Shannon R. Pickens Jonathon R. Lindner Jonathan S. Zora Jessa E. Miller Peter D. Arno Samuel W. Straight Harry L. T. Mobley 《PLoS pathogens》2013,9(9)
The Type VI Secretion System (T6SS) functions in bacteria as a contractile nanomachine that punctures and delivers lethal effectors to a target cell. Virtually nothing is known about the lifestyle or physiology that dictates when bacteria normally produce their T6SS, which prevents a clear understanding of how bacteria benefit from its action in their natural habitat. Proteus mirabilis undergoes a characteristic developmental process to coordinate a multicellular swarming behavior and will discriminate itself from another Proteus isolate during swarming, resulting in a visible boundary termed a Dienes line. Using transposon mutagenesis, we discovered that this recognition phenomenon requires the lethal action of the T6SS. All mutants identified in the genetic screen had insertions within a single 33.5-kb region that encodes a T6SS and cognate Hcp-VrgG-linked effectors. The identified T6SS and primary effector operons were characterized by killing assays, by construction of additional mutants, by complementation, and by examining the activity of the type VI secretion system in real-time using live-cell microscopy on opposing swarms. We show that lethal T6SS-dependent activity occurs when a dominant strain infiltrates deeply beyond the boundary of the two swarms. Using this multicellular model, we found that social recognition in bacteria, underlying killing, and immunity to killing all require cell-cell contact, can be assigned to specific genes, and are dependent on the T6SS. The ability to survive a lethal T6SS attack equates to “recognition”. In contrast to the current model of T6SS being an offensive or defensive weapon our findings support a preemptive mechanism by which an entire population indiscriminately uses the T6SS for contact-dependent delivery of effectors during its cooperative mode of growth. 相似文献
608.
609.
Arno Meyer 《Development genes and evolution》1939,139(2):309-362
Ohne ZusammenfassungD 18. 相似文献