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31.
Fatal attack on an infant by an adult female tonkean macaque 总被引:1,自引:0,他引:1
We describe a fatal attack on a 10-month-old female infant by an adult female Tonkean macaque (Macaca tonkeana)in a semi-free-ranging group. During an intense conflict involving many group members, an adult female, the second most dominant
in the group, attacked the infant of a lower-ranking female. The attacker remained near the victim for approximately 20 min,
grabbing and biting it repeatedly, until the mother retrieved the infant. She died 2 days later. An autopsy revealed no lethal
injury;the main cause of death was starvation or dehydration or both. We discuss social conditions under which a fatal attack by
an adult female might occur. 相似文献
32.
Identification and expression of water stress- and abscisic acid-regulated genes in a drought-tolerant sunflower genotype 总被引:17,自引:0,他引:17
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A new gene coding for an antigen recognized by autologous cytolytic T lymphocytes on a human renal carcinoma 总被引:7,自引:0,他引:7
Béatrice Gaugler Nathalie Brouwenstijn Valérie Vantomme Jean-Pierre Szikora Corry W. Van der Spek Jean-Jacques Patard Thierry Boon Peter Schrier Benoît J. Van den Eynde 《Immunogenetics》1996,44(5):323-330
Previous reports have described antigens that are recognized on human melanoma cells by autologous cytolytic T lymphocytes
(CTL). The genes coding for a number of these antigens have been identified. Here we report the cloning of a gene that codes
for an antigen recognized by autologous CTL on a human renal carcinoma cell line. This antigen is presented byHLA-B7 and is encoded by a new gene that we have namedRAGE1. No expression ofRAGE1 was found in normal tissues other than retina. RAGE1 expression was found in only one of 57 renal cell carcinoma samples,
and also in some sarcomas, infiltrating bladder carcinomas, and melanomas. This represents the first identification of an
antigen recognized by autologous CTL on a renal tumor. 相似文献
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35.
Crystal structure of a prokaryotic aspartyl tRNA-synthetase. 总被引:3,自引:3,他引:0
M Delarue A Poterszman S Nikonov M Garber D Moras J C Thierry 《The EMBO journal》1994,13(14):3219-3229
The crystal structure of Thermus thermophilus aspartyl tRNA-synthetase (AspRS) refined at 2.5 A resolution is described. This molecular structure is a textbook illustration of the modular organization of aminoacyl-tRNA synthetases. In addition to the three domains found in yeast AspRS, each monomer exhibits a module specific to prokaryotic enzymes, which corresponds to a helix-turn-helix motif in yeast AspRS, a domain implicated in the stabilization of the complex with tRNA. Its topology matches that of the histidine-containing phosphocarrier HPr which has been linked recently to another group of proteins containing the ferredoxin fold. We propose a more extensive alignment of these folds, which involves a circular permutation of the sequences and changes the point of entry of the whole domain. The C-terminal extension, another prokaryotic characteristic, leads to a significant increase in the network of interaction at the dimer interface. Some potential communication pathways suggest how a transfer of information between the two active sites of the homodimer might occur. Most of the residues involved belong to the class II-specific motifs in correlation with the dimeric state of nearly all class II enzymes. The T. thermophilus enzyme exhibits some features not found in any of the six other known AspRSs from mesophilic organisms. 相似文献
36.
Bienvenu Thierry Hubert Dominique Fonknechten Nuria Dusser Daniel Kaplan Jean Claude Beldjord Cherif 《Human genetics》1994,94(1):65-68
Human Genetics - Cystic fibrosis is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR). Analysis of DNA from a pancreatic sufficient patient by means of... 相似文献
37.
Immunogenic tumor cell variant P35 was obtained by mutagen treatment of mouse mastocytoma P815. It express a potent new antigen recognized by syngeneic cytolytic T lymphocytes (CTL). This antigen is the result of a point mutation in a gene that is expressed by most healthy cells. A decapeptide encoded by the region spanning the mutation sensitized P815 cells to the relevant CTL, whereas the homologous decapeptide corresponding to the normal sequence did not. Only the mutant decapeptide was capable of enhancing the expression of the Dd-presenting molecule at the cell surface, indicating that the mutation generates a motif which enables the antigenic peptide to bind to Dd.
Correspondence to: T. Boon. 相似文献
38.
Brice Maxime Nkouayeb Nangmou Hermine Laure Maza Djomkam Georges Bellier Tabekoueng Willifred Dongmo Tékapi Tsopgni Gabin Thierry Mbahbou Bitchagno Michel Arnaud Mbock Raceline Gounoue Kamkumo Marcel Frese Bruno Ndjakou Lenta Silvère Augustin Ngouela Nobert Sewald Anatole Guy Blaise Azebaze 《化学与生物多样性》2023,20(4):e202200271
The root extract of Nauclea xanthoxylon (A.Chev.) Aubrév. displayed significant 50 % inhibition concentration (IC50s) of 0.57 and 1.26 μg/mL against chloroquine resistant and sensitive Plasmodium falciparum (Pf) Dd2 and 3D7 strains, respectively. Bio-guided fractionation led to an ethyl acetate fraction with IC50s of 2.68 and 1.85 μg/mL and subsequently, to the new quinovic acid saponin named xanthoxyloside ( 1 ) with IC50s of 0.33 and 1.30 μM, respectively against the tested strains. Further compounds obtained from ethyl acetate and hexane fractions were the known clethric acid ( 2 ), ursolic acid ( 3 ), quafrinoic acid ( 4 ), quinovic acid ( 5 ), quinovic acid 3-O-β-D-fucopyranoside ( 6 ), oleanolic acid ( 7 ), oleanolic acid 3-acetate ( 8 ), friedelin ( 9 ), β-sitosterol ( 10a ), stigmasterol ( 10b ) and stigmasterol 3-O-β-D-glucopyranoside ( 11 ). Their structures were characterised with the aid of comprehensive spectroscopic methods (1 and 2D NMR, Mass). Bio-assays were performed using nucleic acid gel stain (SYBR green I)-based fluorescence assay with chloroquine as reference. Extracts and compounds exhibited good selectivity indices (SIs) of >10. Significant antiplasmodial activities measured for the crude extract, the ethyl acetate fraction and xanthoxyloside ( 1 ) from that fraction can justify the use of the root of N. xanthoxylon in ethnomedicine to treat malaria. 相似文献
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