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141.
142.
M. L. Gorman 《Ibis》1974,116(2):152-154
The significance of habitat selection during nesting of the Eider Somateria mollissima mollissima 相似文献
143.
Helen E. Gorman 《Animal behaviour》2003,65(4):745-754
State dependence is thought to be an important factor in resource allocation decisions, particularly in those decisions relating to parental care. Incubation behaviour is a costly part of avian parental care, and therefore likely to depend on the parent's body condition. We manipulated the body condition of zebra finches, Taeniopygia guttata, during incubation by using prelaying diets of different protein content, and induced birds to lay a similar number of eggs. We tested the hypothesis that birds in better body condition would invest more in incubation than birds in poorer condition when incubating on the same diet. Females that had received a high-protein prelaying diet lost more body mass than those that had received a low-protein diet. They also increased the length of their incubation bouts between early and middle incubation, whereas females that had received a low-protein prelaying diet increased bout length only between middle and late incubation. There were no differences between males from the two diet groups, and males were responsible for a lesser proportion of incubation than females. These results indicate that incubation behaviour is state dependent in female zebra finches, and that birds of different body condition adopt different incubation strategies. We found no differences in incubation duration and hatching success between the two incubation strategies in captivity, but the potential risk of nest predation in the wild may differ. We suggest that only females in good condition can afford to adopt a strategy of increasing bout length early in incubation; females in poorer condition first have to recover their body condition after having produced a clutch. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour 相似文献
144.
Characterization of the sites of proteolytic activation of Newcastle disease virus membrane glycoprotein precursors 总被引:4,自引:0,他引:4
J J Gorman A Nestorowicz S J Mitchell G L Corino P W Selleck 《The Journal of biological chemistry》1988,263(25):12522-12531
The F1- and F2-polypeptide components of the fusion proteins and the hemagglutinin/neuraminidase proteins of the avirulent Queensland (V4) and virulent Australia-Victoria (AuV) strains of Newcastle disease virus have been isolated and subjected to extensive primary structural analysis including amino-terminal sequence analysis and fast atom bombardment-mass spectrometry mapping. Nucleotide sequence analysis was performed on the gene which encodes the V4 hemagglutinin/neuraminidase protein. Signal peptidase cleavage was found to have occurred at the Ser31-Leu32 peptide bond of the primary translation products of the fusion protein genes. Activation cleavage of the V4 fusion protein precursor generated a sequence of -Gly-Lys-Gln-Gly84 at the carboxyl terminus of the F2-polypeptide and an amino-terminal sequence of the F1-polypeptide commencing with 86Leu-Ile-Gly-. The V4 hemagglutinin/neuraminidase protein gene was found to encode a primary translation product 45 amino acids longer at the carboxyl terminus than obtainable from the corresponding gene of the AuV strain (McGinnes, L. W., and Morrison, T. G. (1986) Virus Res. 5, 343-356). However, post-translational proteolytic processing, exclusive to the primary translation product of the V4 hemagglutinin/neuraminidase protein gene, was found to have removed the last 42 residues of this carboxyl-terminal appendage. 相似文献
145.
146.
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149.
Platelet rich plasma transforms exogenous prostaglandin endoperoxide H2 into thromboxane A2 总被引:2,自引:0,他引:2
Platelet rich plasma transforms exogenous prostaglandin endoperoxide H2 into thromboxane A2 immediately prior to the initiation of irreversible aggregation. Selective thromboxane synthetase inhibitors block thromboxane A2 formation and aggregation. Thromboxane A2 formation appears to be essential during arachidonate mediated aggregation. The results presented reconcile the previously accepted paradoxical behavior of thromboxane synthetase in platelet rich plasma toward the prostaglandin endoperoxide H2 substrate. 相似文献
150.
Gorman KF Breden F 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,145(1):28-38
Vertebral development is a dynamic and complicated process, and defects can be caused by a variety of influences. Spinal curvature with no known cause (idiopathic scoliosis) affects 2-3% of the human population. In order to understand the etiology and pathogenesis of complex human skeletal defects such as idiopathic scoliosis, multiple models must be used to study all of the factors affecting vertebral stability and deformity. Although fish and humans have many of the same types of offenses to vertebral integrity, they have been overlooked as a resource for study. The most common morphological deformity reported for fish are those that occur during the development of the spinal system, and as with humans, curvature is a common morphological consequence. Here we review spinal curvature in teleosts and suggest that they are an unexploited resource for understanding the basic elements of vertebral stability, deformity, development and genetics. Fish can be a value to vertebral research because they are tractable, have a diversity of non-induced vertebral deformities, and substantial genomic resources. Current animal models lack non-induced deformities and the experimental tractability necessary for genetic studies. The fact that fish are free of an appendicular skeleton should allow for analysis of basic spinal integrity without the biomechanical constraints observed in quadrupedal and bipedal models. To illustrate the point we review human idiopathic scoliosis and the potential contribution teleosts can make for the identification of causes, risk factors, and treatment options. 相似文献