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991.
Replacement of starch with raffinose in Duncan and Strong sporulation medium improved percent sporulation in six of eight strains tested. Enterotoxin concentration in cell extracts was increased in the case of four of five known enterotoxin-positive strains. With strain NCTC 10240, levels of 0.3, 0.4, and 0.5% raffinose produced the highest enterotoxin concentration 300 to 320 micrograms of enterotoxin per mg of cell extract protein. At a level of 0.4% raffinose the highest enterotoxin concentration in cell extracts of NCTC 10240 occurred after 8 h of growth in Duncan and Strong medium. Enterotoxin produced in the presence of starch or raffinose by three separate strains all migrated at similar Rm by polyacrylamide gel electrophoresis. 相似文献
992.
Erik Volz Verity Hill John T. McCrone Anna Price David Jorgensen Áine O’Toole Joel Southgate Robert Johnson Ben Jackson Fabricia F. Nascimento Sara M. Rey Samuel M. Nicholls Rachel M. Colquhoun Ana da Silva Filipe James Shepherd David J. Pascall Rajiv Shah Natasha Jesudason Thomas R. Connor 《Cell》2021,184(1):64-75.e11
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993.
994.
Marcelo Coelho Goiato Idelmo Rangel Garcia‐Júnior Osvaldo Magro‐Filho Daniela Micheline Dos Santos Eduardo Piza Pellizzer 《Gerodontology》2010,27(3):243-247
doi:10.1111/j.1741‐2358.2009.00283.x Implant‐retained thumb prosthesis with anti‐rotational attachment for a geriatric patient This report presents the use of a dental implant with an anti‐rotational attachment for the retention of a thumb prosthesis. A retention system was manufactured with an attachment (UCLA) screwed into the implant with a two‐bar system that was cast in metallic silver palladium. A substructure made from heat‐cured acrylic resin was joined to the retention system by clips to join the thumb to the finger (bar clip) in the cast with implant rejoinder. The silicone material, Silastic‐MDX 44210, was used to achieve function and aesthetics. Following osseointegration, no skin problems were observed. Whilst the implant‐retained digital prosthesis presented some motor limitations, it allowed the patient to return to entertainment and achieve social conviviality. 相似文献
995.
Iara Augusta Orsi Osvaldo Luiz Bezzon Simone Marchi Flávio Henrique Carriço Nogueira Fernandes 《Gerodontology》2010,27(4):315-318
doi:10.1111/j.1741‐2358.2009.00298.x Use of resin‐bonded extracoronal attachments with removable partial denture: case report Introduction: Resin‐bonded extracoronal attachments may be indicated for the abutment teeth of removable partial dentures, especially for anterior teeth when a cingulum rest must be provided. This type of treatment has a series of advantages such as minimal tooth reduction, supragingival margins, favourable stress distribution, and improved aesthetic appearance. Objective: To report a clinical case of oral rehabilitation using a combination of resin‐bonded extracoronal attachments joined by a Dolder bar with a removable partial denture. Case report: A 60‐year‐old male patient with only the canines in the maxillary arch was restored with a combination of resin‐bonded extracoronal attachments joined by a Dolder bar and a removable partial denture. Conclusion: Dentures with resin‐bonded extracoronal attachments can have a number of advantages over traditional clasp‐retained removable partial dentures. 相似文献
996.
Hosts can protect themselves against parasites by actively reducing parasites burden (i.e. resistance) or by limiting the damages caused by parasites (i.e. tolerance). Disentangling between tolerance and resistance is important for predicting the evolutionary outcomes of host-parasite interaction. Dace (Leuciscus leuciscus) are often parasitized by the ectoparasite Tracheliastes polycolpus which feeds on (and destroys) fins, reducing thus the host’s condition. We tested the hypothesis that genetically-based variation in ectoparasite tolerance exists in a wild dace population. We found that moderately heterozygous dace, which are less resistant than highly heterozygous or homozygous dace, tolerated better the effect imposed by T. polycolpus for a given parasite burden. However, tolerance also varied upon environmental conditions, suggesting that genetic and environmentally-based variation exists for both resistance and tolerance in this natural host-parasite system. Moreover, a negative genetic correlation may exist between tolerance and resistance, and hence several evolutionary outcomes are possible in this interacting system. 相似文献
997.
Nitric oxide affecting root growth,lignification and related enzymes in soybean seedlings 总被引:2,自引:0,他引:2
Franciele Mara Lucca Zanardo Böhm Maria de Lourdes Lucio Ferrarese Daniele Iara Lucca Zanardo Jose Ronaldo Magalhaes Osvaldo Ferrarese-Filho 《Acta Physiologiae Plantarum》2010,32(6):1039-1046
This study analyzed the involvement of nitric oxide (NO) in the root lignification of soybean seedlings. To this end, changes
in root cell viability; phenylalanine ammonia-lyase (PAL) and soluble and cell wall bound peroxidase (POD) activities and
lignin and hydrogen peroxide (H2O2) contents of soybean roots treated with the NO-donor sodium nitroprusside (SNP) and its relationships with root growth were
evaluated. Seedlings were cultivated in a nutrient solution supplemented with 5 to 1,000 μM SNP for 24 h. At an extremely
low concentration (5 μM), SNP induced root growth and increased lignification and activities of related enzymes (PAL and cell
wall-bound POD). At a high concentration (1,000 μM), SNP reduced root growth and lignification (PAL activity and H2O2 and lignin contents) and caused a loss of cell viability. Application of potassium ferrocyanide (an analog of SNP that cannot
release NO) and PTIO (2-phenyl-4,4,5,5,-tetramethylimidazoleline-1-oxyl-3-oxide, a scavenger of NO) revealed that the inhibitory/stimulatory
effects on root lignification may be due to NO itself. These results indicate that NO, depending on its concentration, may
act as a stress factor, due to its toxic action, or as a signal molecule, inducing soybean root growth and lignification. 相似文献
998.
María Jesús Prado Eleazar Rodriguez Laura Rey María Victoria González Conceição Santos Manuel Rey 《Plant Cell, Tissue and Organ Culture》2010,103(1):49-59
Flow cytometry and microsatellite analyses were used to evaluate the trueness-to-type of somatic embryogenesis-regenerated plants from six important Spanish grapevine (Vitis vinifera L.) cultivars. Tetraploid plants were regenerated through somatic embryogenesis from all of the cultivars tested with the exception of ‘Merenzao’. In addition, an octoploid plant was obtained in the cv. ‘Albariño’, and two mixoploids in ‘Torrontés’. The most probable origin of these ploidy variations is somaclonal variation. The cv. ‘Brancellao’ presented significantly more polyploids (28.57%) than any other cultivar, but it must be noted that 50% of the adult field-grown ‘Brancellao’ mother plants analysed were mixoploid. Hence, it is probable that these polyploids originated either from somaclonal variation or by separation of genotypically different cell layers through somatic embryogenesis. Microsatellite analysis of somatic embryogenesis-regenerated plants showed true-to-type varietal genotypes for all plants except six ‘Torrontés’ plants, which showed a mutant allele (231) instead of the normal one (237) at the locus VVMD5. There was not a clear relationship between the occurrence of the observed mutant regenerated plants and the callus induction media composition, the developmental stage of the inflorescences, the type of explant used for starting the cultures or the type of germination (precocious in differentiation medium or normal in germination medium) in any of the cultivars tested, except ‘Torrontés’. The mutant plants described herein have been transplanted to soil for future evaluation of putative phenotypic traits of interest. These mutants can be useful both for breeding programs and for functional genomic approaches aimed at increasing knowledge of the biology of grapevine. 相似文献
999.
Peripheral injection of the endotoxin LPS in rats 3 weeks prior to a second injection of LPS derived from another bacterial
strain results in elevated corticosterone and decreased pro-inflammatory cytokines in the blood. We further investigated this
model by measuring cytokine expression in the hypothalamus and spleen. In LPS-pretreated rats, hypothalamic expression of
a range of cytokines was attenuated in response to the second injection of LPS while splenic expression was elevated. This
is the first demonstration that prior exposure to an endotoxin can differentially affect cytokine expression in the brain
and peripheral tissues when a host is confronted with a second, acute, pro-inflammatory stimulus. Changes in hypothalamic
cytokine expression in endotoxin pretreated rats may provide new evidence for the involvement of central cytokine pathways
in modulating peripheral inflammation and mediating psychopathological alterations associated with inflammatory diseases. 相似文献
1000.
M. Alexandra Esteves Osvaldo Ortet Anabela Capelo Claudiu T. Supuran Sérgio M. Marques M. Amélia Santos 《Bioorganic & medicinal chemistry letters》2010,20(12):3623-3627
A set of benzenesulfonamide (BSA) derivatives bearing a hydroxypyrimidinone (HPM) moiety were synthesized and investigated for their inhibitory activity against several carbonic anhydrase (CA, EC 4.2.1.1) isozymes. They all revealed to be very potent inhibitors (nanomolar order) of the cytosolic CA I and II isozymes, but especially of the transmembrane, tumor-associated CA IX isozyme, a beneficial feature for a potential antitumor effect of these compounds. Further structure optimization aimed at improving the specificity of CA inhibition and enhancing their matrix metalloproteinase (MMP) inhibitory activity may also lead to new compounds with an attractive dual mechanism of action as antitumor agents. 相似文献