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111.
N Robb 《CMAJ》1998,159(5):543-546
Physicians upset by limits imposed by the medicare system are getting a chance to spread their entrepreneurial wings on the East Coast. A boom in offshore exploration, led by Newfoundland''s massive Hibernia project, has led to numerous business opportunities for physicians.  相似文献   
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Original studies leading to the gravitationalmodel of pulmonary blood flow and contemporary studies showinggravity-independent perfusion differ in the recent use of laboratoryanimals instead of humans. We explored the distribution ofpulmonary blood flow in baboons because their anatomy, serialdistribution of vascular resistances, and hemodynamic responses tohypoxia are similar to those of humans. Four baboons wereanesthetized with ketamine, intubated, and mechanically ventilated.Different colors of fluorescent microspheres were given intravenouslywhile the animals were in the supine, prone, upright (repeated), andhead-down (repeated) postures. The animals were killed, and their lungswere excised, dried, and diced into~2-cm3 pieces with the spatialcoordinates recorded for each piece. Regional blood flow was determinedfor each posture from the fluorescent signals of each piece. Perfusionheterogeneity was greatest in the upright posture and least when prone.Using multiple-stepwise regression, we estimate that 7, 5, and 25% ofperfusion heterogeneity is due to gravity in the supine, prone, andupright postures, respectively. Although important, gravity is not thepredominant determinant of pulmonary perfusion heterogeneity in uprightprimates. Because of anatomic similarities, the same may be true for humans.  相似文献   
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We have developed a series of orally efficacious IRAK4 inhibitors, based on a scaffold hopping strategy and using rational structure based design. Efforts to tackle low permeability and high efflux in our previously reported pyrrolopyrimidine series (Scott et al., 2017) led to the identification of pyrrolotriazines which contained one less formal hydrogen bond donor and were intrinsically more lipophilic. Further optimisation of substituents on this pyrrolotriazine core culminated with the discovery of 30 as a promising in vivo probe to assess the potential of IRAK4 inhibition for the treatment of MyD88 mutant DLBCL in combination with a BTK inhibitor. When tested in an ABC-DLBCL model with a dual MyD88/CD79 mutation (OCI-LY10), 30 demonstrated tumour regressions in combination with ibrutinib.  相似文献   
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A pH indicator and dextrose were incorporated into growth media as a modification of microbial microtiter methods for determining the minimal inhibitory concentration of antimicrobial drugs. This modified method was tested to evaluate the ease of reading end points by changes in the indicator color. Application of the procedure to two media, three indicators, and eight species of bacteria indicated that definitive end points could be reached as a result of indicator color change caused by acid production during bacterial growth. This method is accurate and reproducible. It is a modification which eliminates a need for plating and facilitates the reading of minimal inhibitory concentration end points.  相似文献   
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The diet of the Omani Owl, Strix butleri, was studied for the first time based on re- cently collected pellets. A total of 22 individual prey items represented three mam- mals (all rodents), at least two undetermined gecko species and one scorpion. By fre- quency, Acomys cahirinus constituted 31.8% and lizards 27.3%, while Gerbillus nanus and G. dasyurus were the least consumed prey items (4.5% each).  相似文献   
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Although the Omani Owl Strix butleri (A. O. Hume, 1878) was previously reported from southern Iran, this note details the first confirmed records of this species from Mashhad (Khorasan) and Jam (Bushehr) in 2015, after recent revision of the taxonomy of this species in the Middle East.  相似文献   
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Divergence of the hyperthermophilic Archaea, Pyrococcus furiosus and Pyrococcus horikoshii, was assessed by analysis of complete genomic sequences of both species. The average nucleotide identity between the genomic sequences is 70-75% within ORFs. The P. furiosus genome (1.908 mbp) is 170 kbp larger than the P. horikoshii genome (1.738 mbp) and the latter displays significant deletions in coding regions, including the trp, his, aro, leu-ile-val, arg, pro, cys, thr, and mal operons. P. horikoshii is auxotrophic for tryptophan and histidine and is unable to utilize maltose, unlike P. furiosus. In addition, the genomes differ considerably in gene order, displaying displacements and inversions. Six allelic intein sites are common to both Pyrococcus genomes, and two intein insertions occur in each species and not the other. The bacteria-like methylated chemotaxis proteins form a functional group in P. horikoshii, but are absent in P. furiosus. Two paralogous families of ferredoxin oxidoreductases provide evidence of gene duplication preceding the divergence of the Pyrococcus species.  相似文献   
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