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A new anthropometric landmark of the face, called the maxillozygion (mz; right, left) is presented. The bilateral landmark is the most prominent point of the maxillozygomatic suture line, identified by palpation of the most anterior protruding contours on the frontal aspect of the face, located below the lateral third of the right and left bony orbits. The reliability of locating the landmark on both sides of the face by palpation is discussed. Preliminary data determining the position of the maxillozygion in the vertical, sagittal, and horizontal planes in white and Asian sample populations is presented. In general, the Asian face tends to be the same width (zygion [zy]-zy) as the white face; however, the maxillozygion is located more laterally on the Asian face compared with the white face.  相似文献   
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Elastin is a major protein component of the vascular wall and is responsible for its unusual elastic properties. Polymers of its repeating VPGVG sequences have been synthesised and shown to exhibit an inverse temperature transition where, as temperature rises, the polymer collapses from an extended chain to a beta-spiral structure with three VPGVG units per turn, each pentamer adopting a type II beta-turn conformation. These studies, however, have not established whether the temperature-driven conformational change is an intrinsic property of the individual pentameric sequences or a global, co-operative effect of many pentamers within the beta-spiral structure. Here, we examine by circular dichroism the behaviour of elastin-like peptides (VPGVG)n, where n varies between 1 and 5. Remarkably, we find that all lengths of peptide undergo an extended left and right arrow beta-turn transition with increasing temperature, suggesting that the induction of the beta-spiral occurs at the level of single pentameric units. The origin of this effect is a positive DeltaS term for the transition. At 35 degreesC, the average transition midpoint temperature, the value of TDeltaS is about 15 kcal mol-1. With larger oligomers (n=3), there is only a modest rise in DeltaS, suggesting that the dominant entropic effect resides within the monomer and that interactions between these units make only a small contribution to the energetics of the transition. Charges at the termini, and residue replacements or additions, regulate the transitions for the short peptides in a manner similar to that observed for the longer polymers. The behaviour of the same peptides in trifluoroethanol and SDS solutions is consistent with formation of the beta-turn being driven by interactions between non-polar groups. The significance of this behaviour for the rational design of temperature-induced responses in proteins is discussed.  相似文献   
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