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61.
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What's wrong with inclusive fitness? 总被引:1,自引:0,他引:1
Fletcher JA Zwick M Doebeli M Wilson DS 《Trends in ecology & evolution》2006,21(11):597-8; author reply 599-600
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New skeletal elements are reported of the holotype specimen Australovenator wintonensis, from the type locality, near Winton, central western Queensland. New elements include left and right humeri, right radius, right radiale, right distal carpal 1, near complete right metacarpal I, left manual phalanx II-1, left manual phalanx II-2, near complete left manual phalanx II-3 and a left manual phalanx III-3. These new elements combined with those previously described are compared against other neovenatorids. 相似文献
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Sloan PR 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2012,43(1):140-151
This paper approaches the issue of the status of teleological reasoning in contemporary biology through a historical examination of events of the 1930s that surrounded Niels Bohr’s efforts to introduce ‘complementarity’ into biological discussions. The paper examines responses of three theoretical physicists who engaged boundary questions between the biological and physical sciences in this period in response to Bohr—Ernst Pascual Jordan (1902–80), Erwin Schrödinger (1887–1961), and Max Delbrück (1906–81). It is claimed that none of these physicists sufficiently understood Bohr’s ‘critical’ teleological arguments, which are traced to the lineage of Kant and Harald Høffding and their respective resolutions of the Antinomy of Teleological Judgment. The positions of these four historical actors are discussed in terms of Ernst Mayr’s distinction of ‘teleological,’ ‘teleomatic,’ and ‘teleonomic’ explanations. A return to some of the views articulated by Bohr, and behind him, to Høffding and Kant, is claimed to provide a framework for reintroducing a ‘critical’ teleology into biological discussions. 相似文献
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The Us5 gene of herpes simplex virus (HSV) encodes glycoprotein J (gJ). The only previously reported function of gJ was its ability to inhibit apoptosis. However, the mechanism by which gJ prevents apoptosis is not understood, and it is not known whether gJ mediates additional cellular effects. In this study, we evaluated the expression, localization, and cellular effects of Us5/gJ. Us5 was first expressed 4 h after infection. gJ was detectable at 6 h and was expressed in glycosylated and unglycosylated forms. Us5 was regulated as a late gene, with partial dependency on DNA replication for expression. Us5 expression was delayed in the absence of ICP22; furthermore, expression of Us5 in trans protected cells from apoptosis induced by an HSV mutant with deletion of ICP27, suggesting that the antiapoptotic effects of ICP22 and ICP27 are mediated in part through effects on gJ expression. Within HSV-infected or Us5-transfected cells, gJ was distributed widely, especially to the endoplasmic reticulum, trans-Golgi network, and early endosomes. gJ interacted with FoF1 ATP synthase subunit 6 by a yeast two-hybrid screen and had strong antiapoptotic effects, which were mediated by protein rather than mRNA. Antiapoptotic activity required the extracellular and transmembrane domains of gJ, but not the intracellular domain. Consistent with inhibition of FoF1 ATP synthase function, Us5 was required for HSV-induced reactive oxygen species (ROS) formation, and gJ was sufficient to induce ROS in Us5-transfected cells. Thus, HSV gJ is a multifunctional protein, modulating other cellular processes in addition to inhibition of apoptosis. 相似文献
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Nicotinamide deamidase (YNDase) has been purified from yeast through the use of a six-step procedure that includes molecular-sieve high performance liquid chromatography. The final preparation was homogeneous by the criteria of sodium dodecyl sulfate-gel electrophoresis, and the enzyme specific activity was determined to be 175 mumol of nicotinate formed per min/mg enzyme. Gel electrophoresis and molecular-sieve high performance liquid chromatography were employed also to characterize YNDase as a monomeric protein with a molecular weight of 34,000. A Km value for nicotinamide of 33 microM was determined for the deamidase activity at pH 6, and a pH range for optimal stability of 6-8.5 was established for this enzyme. The YNDase activity was also examined over a pH range at several substrate concentrations and both the log Vmax and log Vmax/Km plots versus pH suggested that a protonated amino acid residue with an apparent pKb value of 7.8 was essential to this activity. During an in vitro assay of the YNDase-catalyzed formation of nicotinate, ammonia was generated and detected chemically. Inhibition of the YNDase activity by nicotinaldehyde suggested the presence of either an essential lysine (Schiff's base formation) or cysteine residue (thiohemiacetal intermediate) at the YNDase active site. The relatively large value of the nicotinaldehyde inhibition constant (Ki = 68 microM), the observation that this analogue is a noncompetitive inhibitor of nicotinate formation, and the fact that this inhibition can be rendered irreversible through incubation with sodium borohydride, indicates that a Schiff's base intermediate is more likely to occur upon incubation of YNDase with nicotinaldehyde. However, YNDase is inactivated completely and irreversibly by N-ethylmaleimide at pH 6, and the enzyme is protected against this modification by either nicotinamide or nicotinate. These results suggest that both nicotinate and nicotinamide bind to YNDase, even though the enzymatic reaction is essentially irreversible, and that a cysteine residue may be present at the YNDase active site. 相似文献
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Partial covalent labeling of band 3 protein lysines with pyridoxal 5'-phosphate (a substrate and affinity probe) changes the bis(sulfosuccinimidyl)suberate crosslinking pattern of band 3 in intact red cells from a mixture of dimers and tetramers to all tetramers as the exclusive crosslinked product. This is the first demonstration of band 3 crosslinkage to the tetrameric level within membranes of intact red cells. The possible implications of the ligand-induced change in the band 3 crosslinking pattern are discussed. 相似文献