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61.
Bill Jones Teresa Anuza 《Cortex; a journal devoted to the study of the nervous system and behavior》1982,18(4):501-514
Shepard's mental rotation paradigm (e.g. Shepard and Metzler, 1971) was modified to allow tachistoscopic presentation of stimuli at varying angles of orientation (0° to 180°) in the right and left visual fields. Thirty male and thirty female subjects divided into three handedness groups (right-handers, non-familial and familial left-handers) judged whether a stimulus was a standard form or its mirror image. In general response times for correct judgements (RTc) increased monotonically as a function of angle of orientation though the curves tended to be negatively accelerated rather than linear. Right-handers showed a slower rate of increase in RTc as a function of angle than either left-handed group. Mean RTc and the rate of increase in RTc were equivalent for the two sexes and for the two visual fields. Both mean RTcs and on the rate of increase in RTc varied as a function of the stimulus.Error rates also increased monotonically as a function of angle of orientation. No sex or handedness differences in error rates were found. However, errors increased significantly less rapidly when stimuli were presented in the left visual field. It is argued that right hemisphere specialization for spatial processing minimizes the rate of increase in errors.The present failure to find sex differences may be of interest and it is argued that rapid presentation of stimuli results in subjects setting maximum and minimun response times. Within this relatively restricted “bandwith” of response times males and females may perform spatial tasks equally efficiently. Some confirmation for this hypothesis vs. an alternative based upon differences in hemispheric organization was found in a second experiment. 相似文献
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M. Petschler M. Stiller B. Hoffmeister R. Witkowski C. Opitz J. S. Bill H. Peters 《Mund-, Kiefer- und Gesichtschirurgie》2003,1(1):83-87
Hintergrund
Cherubismus ist eine seltene genetisch bedingte Erkrankung der Knochen, die fast ausschlie?lich den Ober- und Unterkiefer betrifft. 相似文献63.
Riley RD Sato H Zhao ZQ Thourani VH Jordan JE Fernandez AX Ma XL Hite DR Rigel DF Pellas TC Peppard J Bill KA Lappe RW Vinten-Johansen J 《The Journal of thoracic and cardiovascular surgery》2000,120(2):350-358
OBJECTIVES: This study tested the hypothesis that a recombinant human C5a antagonist, CGS 32359, attenuates neutrophil activation and reduces infarct size in a porcine model of surgical revascularization. METHODS: CGS 32359 (0.16-16 micromol/L) dose-dependently inhibited superoxide production by human C5a-activated porcine neutrophils (18 +/- 3.7 vs 1.6 +/- 0.5 nmol/5 min/5 x 10(6) neutrophils; P <.05) and reduced neutrophil adherence to coronary endothelium from 194 +/- 9 to 43 +/- 6 neutrophils/mm(2) (P <.05). The left anterior descending coronary artery was occluded for 50 minutes, after which saline solution (n = 8), mannitol-buffer vehicle (n = 9, 102 mg/kg bolus, 102 mg. kg(-1). h(-1)), or CGS 32359 (CGS, n = 7, 60 mg/kg bolus, 60 mg. kg(-1). h(-1)) was infused. After ischemia, 1-hour arrest was achieved by means of multidose hypothermic (4 degrees C) blood cardioplegia, followed by 2.5 hours of off-bypass reperfusion. The ligature on the left anterior descending artery was released before the second infusion of cardioplegic solution. RESULTS: Area at risk was similar in all groups (saline solution, 27% +/- 2%; mannitol-buffer vehicle, 26% +/- 2%; CGS, 26% +/- 2% left ventricular mass). Infarct size (area necrosis/area at risk) was significantly reduced by CGS (18% +/- 6%, P <.05) versus saline solution (52% +/- 3%) and mannitol-buffer vehicle (60% +/- 4%). Postischemic systolic shortening (sonomicrometry) in the area at risk was significantly improved with CGS (0.8% +/- 0.9%) compared with saline solution (-3.7% +/- 1.1%) and mannitol-buffer vehicle (-6.4% +/- 1.0%). Myeloperoxidase activity from accumulated neutrophils was less in the ischemic zone of CGS (0.014 +/- 0.002 U/100 mg tissue; P <.05) than mannitol-buffer vehicle (0.133 +/- 0.012 U/100 mg tissue). CONCLUSIONS: We conclude that the recombinant human C5a receptor antagonist CGS 32359 inhibits surgical ischemia-reperfusion injury after coronary occlusion. 相似文献
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Daniel R. Feikin M. Kariuki Njenga Godfrey Bigogo Barrack Aura Stella Gikunju Amanda Balish Mark A. Katz Dean Erdman Robert F. Breiman 《Clinical and Vaccine Immunology : CVI》2013,20(1):113-114
The role of serology in the setting of PCR-based diagnosis of acute respiratory infections (ARIs) is unclear. We found that acute- and convalescent-phase paired-sample serologic testing increased the diagnostic yield of naso/oropharyngeal swabs for influenza virus, respiratory syncytial virus (RSV), human metapneumovirus, adenovirus, and parainfluenza viruses beyond PCR by 0.4% to 10.7%. Although still limited for clinical use, serology, along with PCR, can maximize etiologic diagnosis in epidemiologic studies. 相似文献
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