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Osteomyelitis in uncommon locations can present unusual diagnostic difficulties. A patient with primary sternal osteomyelitis who presented with pain over the right supraclavicular area and a radiologic picture of a pleural-based right upper lung mass is discussed. A triple-phase bone scan was consistent with the diagnosis, and a needle aspiration of the mass revealed a staphylococcal abscess. Percutaneous drainage of the contiguous abscess and a prolonged course of antibiotic therapy cured the infection. 相似文献
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D Jacob-Wilk EE Goldschmidt J Riov A Sadka D Holland 《Canadian Metallurgical Quarterly》1997,35(5):661-666
In response to a light pulse, hamsters normally generate phase advances that are positively correlated with the length of their circadian period (tau). To determine whether this is a general property of the phase-shifting oscillator, the present study looked for a correlation between tau and phase-advance size not only for photic but also for nonphotic shifts. Syrian hamsters, Mesocricetus auratus, were entrained to light-dark cycles with a periodicity of either 23.67 h (the short-T group) or 24.33 h (the long-T group); after release into constant darkness, the short-T and long-T groups exhibited short and long taus, respectively. These animals were then induced to run in a novel exercise wheel for 3 h, starting at circadian time (CT) 7, or were exposed to 20 min of light, starting at CT 19. The size of the ensuing phase advances did not differ between the short-T and long-T groups not only for the nonphotic stimulus but also for the photic one, an unexpected result for the photic stimulus. Within the short-T groups for photic and nonphotic stimuli, the shorter tau was, the larger the phase advances were, another unexpected relationship. Another experiment where phase delays were induced by light pulses at CT 15 also failed to yield significant differences between the short-T and long-T groups. Independently of their after-effects on tau, T cycles may influence the capacity of the pacemaker to phase shift in ways that are still unclear but at least similar for both photic and nonphotic shifts. 相似文献
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This study investigated whether sex discrimination existed in recruiters' evaluations of applicants in real employment interviews and, if so, whether other variables could explain it. The variables examined were the perceived similarity of the applicant to the recruiter, the interpersonal attraction felt by the recruiter toward the applicant, and the applicant's objectively measured and subjectively measured qualifications. Applicant sex did not directly or indirectly affect recruiters' evaluations of applicants in campus interviews, providing no evidence of sex discrimination. Instead, subjective qualifications had a significant effect on evaluations and also mediated the effects of perceived similarity, interpersonal attraction, and objective qualifications on evaluations. Recruiters saw stronger subjective qualifications in applicants with high scholastic performance whom they viewed as similar to themselves and whom they liked. Perceptions of these qualifications, in turn, were the primary determinant of evaluations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Comparison of orthorhombic and alpha-two titanium aluminides as matrices for continuous SiC-reinforced composites 总被引:1,自引:0,他引:1
P. R. Smith J. A. Graves CG. Rhodes 《Metallurgical and Materials Transactions A》1994,25(6):1267-1283
The attributes of an orthorhombic Ti aluminide alloy, Ti-21Al-22Nb (at. pct), and an alpha-two Ti aluminide alloy, Ti-24Al-11Nb
(at. pct), for use as a matrix with continuous SiC (SCS-6) fiber reinforcement have been compared. Foil-fiber-foil processing
was used to produce both unreinforced (“neat”) and unidirectional “SCS-6” reinforced panels. Microstructure of the Ti-24A1-11Nb
matrix consisted of ordered Ti3Al (α
2) + disordered beta(β), while the Ti-21 Al-22Nb matrix contained three phases: α2, ordered beta (β
0), and ordered orthorhombic(O). Fiber/ matrix interface reaction zone growth kinetics at 982 °C were examined for each composite system. Although both systems
exhibited similar interface reaction products(i.e., mixed Ti carbides, silicides, and Ti-Al carbides), growth kinetics in theα
2 +β matrix composite were much more rapid than in theO +β
0 +α
2 matrix composite. Additionally, interfacial reaction in theα
2 +β} composite resulted in a relatively large brittle matrix zone, depleted of beta phase, which was not present in theO +β
0+α
2 matrix composite. Mechanical property measurements included room and elevated temperature tensile, thermal stability, thermal
fatigue, thermo-mechanical fatigue (TMF), and creep. The three-phase orthorhombic-based alloy outperformed the α2+β alloy in all of these mechanical behavioral areas, on both an absolute and a specific(i.e., density corrected) basis. 相似文献
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