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51.
52.
Camille Daujeard Denis Geraads Rosalia Gallotti David Lefèvre Abderrahim Mohib Jean-Paul Raynal Jean-Jacques Hublin 《PloS one》2016,11(4)
In many Middle Pleistocene sites, the co-occurrence of hominins with carnivores, who both contributed to faunal accumulations, suggests competition for resources as well as for living spaces. Despite this, there is very little evidence of direct interaction between them to-date. Recently, a human femoral diaphysis has been recognized in South-West of Casablanca (Morocco), in the locality called Thomas Quarry I. This site is famous for its Middle Pleistocene fossil hominins considered representatives of Homo rhodesiensis. The bone was discovered in Unit 4 of the Grotte à Hominidés (GH), dated to c. 500 ky and was associated with Acheulean artefacts and a rich mammalian fauna. Anatomically, it fits well within the group of known early Middle Pleistocene Homo, but its chief point of interest is that the diaphyseal ends display numerous tooth marks showing that it had been consumed shortly after death by a large carnivore, probably a hyena. This bone represents the first evidence of consumption of human remains by carnivores in the cave. Whether predated or scavenged, this chewed femur indicates that humans were a resource for carnivores, underlining their close relationships during the Middle Pleistocene in Atlantic Morocco. 相似文献
53.
Luciano Polonelli Stefania Manzara Stefania Conti Giuseppe Dettori Giulia Morace Carlo Chezzi 《Mycopathologia》1989,108(3):211-215
Yeast killer toxins coded by determined and undetermined killer plasmids or presumptive nuclear gene(s) in various genera (Saccharomyces, Kluyveromyces, Pichia and Candida) have been serologically investigated by a monoclonal antibody (KT4), produced against the yeast killer toxin of Pichia (Hansenula) anomala UCSC 25F. Double immunodiffusion with the killer toxins as antigens and indirect immunofluorescence on whole cells of the corresponding killer yeast have been used. In both the serological procedures, monoclonal antibody KT4 proved to be reacting only with the killer toxins and the whole cells of yeasts belonging to the genus Pichia. 相似文献
54.
T.K. Sasikumar Li Qiang Duane A. Burnett William J. Greenlee Cheng Li Mariagrazia Grilli Rosalia Bertorelli Gianluca Lozza Angelo Reggiani 《Bioorganic & medicinal chemistry letters》2010,20(8):2474-2477
A-ring modifications on the triazafluorenone core structure were investigated. Five membered heterocycles such as pyrazoles and isothiazoles are not tolerated. It has been found that the pyrimidine nucleus was very well tolerated on the left hand side. Amino pyrimidine compounds 24 and 27 showed acceptable PK profile with significant brain penetration. Compound 9 served as a versatile intermediate for a number of chemical transformations. 相似文献
55.
Gerald Reese Detlef Schmechel Rosalia Ayuso Samuel B. Lehrer 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,756(1-2)
Grid-immunoblotting is a procedure that allows the simultaneous testing of up to 20 different antibodies such as monoclonal antibody-containing hybridoma supernatants or human sera for specific antibodies to up to 20 different antigens or allergens on a single sheet of nitrocellulose membrane. Since only 150 to 200 μl of antibody-containing solution are required this technique is uniquely suited to test growing hybridomas and small amounts of sera (e.g. mouse and children’s sera). Compared to a standard ELISA, approximately ten times less antibody is needed to obtain the same information. 相似文献
56.
Dettori S Argentini C Marcucci F Spada E Chionne P Candido A Madonna E Ciccaglione AR Bianco E Iannitto E Musto P Liso V De Renzo A Pagano L Nieddu G Pulsoni A Mele A Rapicetta M 《The new microbiologica》2007,30(3):265-270
We compared the E2-HVR1 region in HCV-1b positive B-NHL cases from a multicenter study with sequences from studies related to lymphoproliferative disorders and B cell compartmentalisation. We found rare and unique mutations both in B-NHL isolates and in cases with lymphoproliferative disorders and lymphocyte infection. These rare mutations could have an important effect on HVR1 region and, as a consequence, on the binding of E2 on CD81, with a possible implication for both antigenic stimulation and HCV entry. In conclusion, the HCV predominants circulating in B-NHL cases seem to be associated with clonal selection of rare variants. 相似文献
57.
Diversity of the nitrite reductase gene nirS in the sediment of a free-water surface constructed wetland. 总被引:1,自引:0,他引:1
Olaya Ruiz-Rueda Rosalia Trias Librado J Garcia-Gil Lluís Ba?eras 《International microbiology》2007,10(4):253-260
The diversity of the nitrite reductase gene nirS was studied in the bulk sediment of a free-water surface constructed wetland (FWS-CW) located next to the Empuriabrava wastewater treatment plant (WWTP), in Castelló d'Empúries (Girona, NE Spain). The study period extended from the inception of the treatment wetland, in June 1998, until March 1999 and comprised periods of relatively high nitrate and ammonium concentrations at the influent and low nitrate-removal efficiencies. To evaluate nirS diversity, partial gene sequences were obtained by cloning of the respective PCR products. Rarefaction curves based on DOTUR analyses of the deduced amino-acid sequences predicted a greater diversity of nirS genes in samples containing higher ammonium concentrations. Estimated Shannon-Weaver indices of the four cloned samples showed a positive relationship with the N-NH4 +/N-NO3 - ratios measured at the FWS-CW inlet. Identities between the deduced amino-acid sequences and those previously deposited in public databases ranged from 72 to 97%. Phylogenetic analysis based on these deduced sequences grouped 165 nirS clones in seven main clusters according to high similarity indices. Up to 60% of the clones clustered together in a highly homogeneous group with little homologies to any sequence retrieved from cultured representatives. Moreover, prevailing environmental conditions appeared to select for particular denitrifying populations, e.g., with respect to ammonium load and nitrogen removal efficiencies. This observation is of particular interest for the management of treatment wetlands, in which only slight variations in the theoretical denitrification potential of the system can occur. 相似文献
58.
59.
Buroni S Pasca MR de Jesus Lopes Ribeiro AL Degiacomi G Molteni E Riccardi G 《Applied microbiology and biotechnology》2012,94(4):907-916
Multidrug resistance is a major barrier in the battle against tuberculosis and still a leading cause of death worldwide. In
order to fight this pathogen, two routes are practicable: vaccination or drug treatment. Vaccination against Mycobacterium tuberculosis with the current vaccine Mycobacterium bovis Bacillus Calmette–Guerin is partially successful, being its efficacy variable. A few new tuberculosis vaccines are now in
various phases of clinical trials. The emergence of multidrug-resistant strains of M. tuberculosis gave the impulse to discover new effective antitubercular drugs, a few of which are in clinical development. Here we focus
on three different classes of very promising antitubercular drugs recently discovered (benzothiazinones, dinitrobenzamides,
and benzoquinoxalines) that share the same cellular target: a subunit of the heteromeric decaprenylphosphoryl-β-d-ribose 2′-epimerase, encoded by the dprE1 (or Rv3790) gene. This enzyme is involved in the biosynthesis of d-arabinose which is crucial for the synthesis of the mycobacterial cell wall and essential for the pathogen’s survival. 相似文献
60.