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991.
F. Marsolat D. Tromson N. Tranchant P. Bergonzo F. Moignau L. De Carlan D. Lazaro M. Agelou C. Bassinet C. Huet S. Derreumaux M. Chea G. Boisserie I. Buchheit V. Marchesi 《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2012
992.
S. J. Tzartos M. T. Cung P. Demange H. Loutrari A. Mamalaki M. Marraud I. Papadouli C. Sakarellos V. Tsikaris 《Molecular neurobiology》1991,5(1):1-29
Myasthenia gravis (MG) is caused by autoantibodies against the nicotinic acetylcholine receptor (AChR) of the neuromuscular junction. The anti-AChR antibodies are heterogeneous. However, a small region on the extracellular part of the AChR alpha subunit, called the main immunogenic region (MIR), seems to be the major target of the anti-AChR antibodies, but not of the specific T-cells, in experimental animals and possibly in MG patients. The major loop of the overlapping epitopes for all testable anti-MIR monoclonal antibodies (MAbs) was localized within residues 67-76 (WNPADYGGIK for Torpedo and WNPDDYGGVK for human AChR) of the alpha subunit. The N-terminal half of alpha 67-76 is the most critical, Asn68 and Asp71 being indispensable for binding. Yet anti-MIR antibodies are functionally and structurally quite heterogeneous. Anti-MIR MAbs do not affect channel gating, but they are very potent in mediating acceleration of AChR degradation (antigenic modulation) in cell cultures and in transferring experimental MG in animals. Fab fragments of anti-MIR MAbs bound to the AChR prevent the majority of the MG patients' antibodies from binding to and causing loss of the AChR. Whether this inhibition means that most MG antibodies bind on the same small region or is a result of broad steric/allosteric effects is under current investigation. 相似文献
993.
994.
Molecular determinants of visual pigment function. 总被引:1,自引:0,他引:1
M L Applebury 《Current opinion in neurobiology》1991,1(2):263-269
Mutagenesis studies and comparisons of natural variants of rhodopsin and related visual pigments have led to new insights concerning photoreceptor function. The studies identify domains important for receptor folding, the residues that set the wavelength of absorption for the ligand 11-cis retinal, and residues, that when mutated, trigger the cell death of photoreceptors. 相似文献
995.
996.
A crown-of-thorns starfish control program was conducted at Grub Reef (central Great Barrier Reef) in an area (0.64 km2) which encompassed 53 individual patch reefs. During a two week period, 15 divers injected 3175 starfish with copper sulphate. The program was considered unsuccessful. Although starfish abundance had declined significantly after the control efforts, biological surveys indicated that a relatively large number of starfish remained. The surveys also indicated a general decline in the number of starfish along the reef perimeter, outside the control area. The total cost of the control program was $35 per starfish. These results have important implications for the implementation of future control programs and highlight the need to undertake before and after biological surveys to assess the effectiveness of the control efforts. 相似文献
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998.
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1000.
Jeff A Johnson Heather RL Lerner Pamela C Rasmussen David P Mindell 《BMC evolutionary biology》2006,6(1):65-12