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81.
Reconstruction of the lower lip and chin with the composite radial forearm-palmaris longus free flap
Four cases of total lip and chin reconstruction are presented. In three, the composite radial forearm-palmaris longus free flap was used for reconstruction. In the fourth case, the palmaris longus was separated from the flap but still used as a lower lip sling. In all cases, the entire lower lip and the soft tissue of the chin were reconstructed in one stage. All patients healed primarily, and the three who underwent radiotherapy tolerated it without complications. Lip seal and speech were good, and there was no problem with drooling. Postoperative results emphasize the importance of respecting the aesthetic unit of the lower lip and chin. 相似文献
82.
Drosophila fat body protein P6 and alcohol dehydrogenase are derived from a common ancestral protein
Summary
Drosophila melanogaster alcohol dehydrogenase is an example of convergent evolution: it is not related to the ADHs of other organisms, but to short-chain dehydrogenases, which until now have been found only in bacteria and in mammalian steroid hormone metabolism. We present evidence that theDrosophila ADH is phylogenetically more closely related to P6, another highly expressed protein from the fat body ofDrosophila, than it is to the short-chain dehydrogenases. The polypeptide sequence of P6 was inferred from DNA sequence analysis. Both ADH and P6 polypeptides have retained a high structural similarity with respect to the Chou-Fasman prediction of secondary structure and hydropathy. P6 is also homologous to the 25-kd protein from the fat body ofSarcophaga peregrina, whose sequence we have reexamined. The evolution of the P6-ADH family of proteins is characterized by a dramatic increase in the methionine content of P6. Methionine accounts for 20% of P6 amino acids. This is in contrast with the absence of this amino acid in mature ADH. There is evidence that P6 and the 25-kd protein have undergone a parallel and independent enrichment in methionine. When corrected for this, the rate of amino acid replacement shows that the P6-25-kd lineage diverged from insect ADH shortly before the divergence of the ADH gene (Adh) from its 3-duplication (Adhdup). 相似文献
83.
Sarcomas after inoculation of newborn hamsters with Herpes virus hominis type 2 strains 总被引:4,自引:0,他引:4
84.
85.
E. Luce E. Bezzel G. Diesselhorst S. Schuster K. Immelmann und J. Nicolai 《Journal of Ornithology》1973,114(2):253-257
Ohne Zusammenfassung 相似文献
86.
The records of 1,020 major facial fractures were reviewed, and it was found that the occurrence of life-threatening associated injuries was highly predictable on the basis of the pattern of facial fractures and the circumstances of the injury. Certain groups of patients have a high probability of associated serious injuries of the central nervous system, the trunk, or the extremities. Probably these patients should be primarily under the care of a surgeon who is capable of the diagnosis and emergency therapy of these associated injuries, as well as the facial injuries, so that appropriate priorities can be established and put in effect. 相似文献
87.
88.
We review the history and current efforts to assess and improve health care in the United States. This process has involved a host of government agencies and commissions, professional organizations, insurance underwriters, corporations, and more recently, market forces. Traditional approaches to quality control have stressed case-by-case analysis and identifying outliers. Newer approaches include creating practice guidelines and profiles of hospitals and physicians. The joint goals of quality improvement and cost control can best be realized if institutions and practitioners embrace these new approaches and use them to enhance their performances. 相似文献
89.
Mamady Diabate Patrick Munro Elsa Garcia Arnaud Jacquel Gregory Michel Sandrine Obba Diogo Goncalves Carmelo Luci Sandrine Marchetti Dieter Demon Clara Degos Yassina Bechah Jean-Louis Mege Mohamed Lamkanfi Patrick Auberger Jean-Pierre Gorvel Lynda Maria Stuart Luce Landraud Emmanuel Lemichez Laurent Boyer 《PLoS pathogens》2015,11(3)
The detection of the activities of pathogen-encoded virulence factors by the innate immune system has emerged as a new paradigm of pathogen recognition. Much remains to be determined with regard to the molecular and cellular components contributing to this defense mechanism in mammals and importance during infection. Here, we reveal the central role of the IL-1β signaling axis and Gr1+ cells in controlling the Escherichia coli burden in the blood in response to the sensing of the Rho GTPase-activating toxin CNF1. Consistently, this innate immune response is abrogated in caspase-1/11-impaired mice or following the treatment of infected mice with an IL-1β antagonist. In vitro experiments further revealed the synergistic effects of CNF1 and LPS in promoting the maturation/secretion of IL-1β and establishing the roles of Rac, ASC and caspase-1 in this pathway. Furthermore, we found that the α-hemolysin toxin inhibits IL-1β secretion without affecting the recruitment of Gr1+ cells. Here, we report the first example of anti-virulence-triggered immunity counteracted by a pore-forming toxin during bacteremia. 相似文献
90.
Recent studies have shown how alternative splicing (AS), the process by which eukaryotic genes express more than one product, affects protein sequence and structure. However, little information is available on the impact of AS on protein dynamics, a property fundamental for protein function. In this work, we have addressed this issue using molecular dynamics simulations of the isoforms of two model proteins: glutathione S-transferase and ectodysplasin-A. We have found that AS does not have a noticeable impact on global or local structure fluctuations. We have also found that, quite interestingly, AS has a significant effect on the coupling between key structural elements such as surface cavities. Our results provide the first atom-level view of the impact of AS on protein dynamics, as far as we know. They can contribute to refine our present view of the relationship between AS and protein disorder and, more importantly, they reveal how AS may modify structural dynamic couplings in proteins. 相似文献