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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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We report a very rare case of an avulsion of the pectoralis major tendon in association with a two-part proximal humerus fracture. Pectoralis major tendon avulsion was confirmed intraoperatively during open reduction and internal fixation of the humerus fracture. In retrospect, the preoperative radiographic finding of posterolateral and proximal displacement of the humeral shaft suggested an injury to the pectoralis major. Because others have reported that the best treatment of a pectoralis major tendon avulsion is surgical repair, we feel that it is important to suspect such an injury in a proximal humerus fracture when this anatomic displacement is present. 相似文献
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ZT Lalowicz M Punkkinen AH Vuorim?ki EE Ylinen A Detken LP Ingman 《Canadian Metallurgical Quarterly》1997,8(2):89-107
Expressions are derived for the initial relaxation rate 1/T1 of protons and deuterons of nontunnelling NH4 and ND4 groups reorienting about various symmetry axes in solids. The reorientation rates are modified by a trigonal, tetragonal or monoclinic distortion of the predominantly cubic hindering potential. When the rates differ sufficiently from each other, two T1 minima are observed with a characteristic ratio. Experiments were performed in NH4VO3, (NH4)2S2O8, (NH4)2PtCl4, and their deuterated modifications, which all exhibit two T1 minima. In NH4VO3 and ND4VO3 the relaxation and spectral data agree rather well with the model of trigonal distortion. Also (NH4)2S2O8 has a preferred threefold axis but there, the large tunnel splitting of protons has to be taken into account before an agreement is reached. All the purely reorientational models fail with (NH4)2PtCl4, where, instead, the ammonium groups are proposed to be ordered into domains at low temperatures. The groups inside the domains and boundary regions give rise to the high- and low-temperature T1 minima, respectively. The boundaries are also believed to give rise to the narrow component in the deuteron spectrum at low temperatures. Evidence for a proton tunnelling frequency of 32 MHz is found in (NH4)2PtCl4. 相似文献