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AIDS and Behavior - We investigated the rate and predictors of ineffective HIV protection in men who have sex with men (MSM) taking pre-exposure prophylaxis (PrEP) in a prospective cohort study...  相似文献   
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The cyanobacterial circadian clock is composed of three clock proteins, KaiA, KaiB and KaiC. This KaiABC clock system can be reconstituted in vitro in the presence of adenosine triphosphate (ATP) and Mg2+, and shows circadian rhythms in the phosphorylation level and ATPase activity of KaiC. Previously, we found that ATP regulates a complex formation between KaiB and KaiC, and KaiC releases ATP from KaiC itself (PLoS One, 8, 2013, e80200). In this study, we examined whether the ATP release from KaiC shows any rhythms in vitro. We monitored the release of ATP from wild-type and ATPase motif mutants of KaiC as a bioluminescence in real time using a firefly luciferase assay in vitro and obtained the following results: (a) ATP release from KaiC oscillated even without KaiA and KaiB although period of the oscillation was not 24 hr; (b) ATP was mainly released from the N-terminal domain of KaiC; and (c) the ATP release was enhanced and suppressed by KaiB and KaiA, respectively. These results suggest that KaiC can generate basal oscillation as a core clock without KaiA and KaiB, whereas these two proteins contribute to adjusting and stabilizing the oscillation.  相似文献   
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Annals of Nuclear Medicine - To examine the impact of acquisition time on Lutetium-177 (177Lu) single-photon emission computed tomography (SPECT) images using Monte Carlo simulation. A gamma camera...  相似文献   
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We report a 72-year-old man with respiratory involvement of immunoglobulin G4 (IgG4)-related disease, who developed dry cough and shortness of breath on effort. The chest computed tomography scan image showed massive and diffuse ground-glass opacity, interlobular thickening, and bronchial wall thickening. The infiltration of IgG4-positive plasma cells in the transbronchial lung biopsy and high serum IgG4 concentrations were found. The patient was treated with 0.6?mg/kg oral prednisolone and showed rapid improvement. This is a case of IgG4-related disease in which the only complication was respiratory involvement.  相似文献   
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We evaluated the tibial tubercle position in knees with patellar instability. CT in full extension and at 30° flexion was used in 18 knees with instability and 18 control knees. Scans were taken at the level of the femoral epicondyles, tibial tubercle and distal tibia. We found that in full extension, the tibial tubercle was in a more lateral position in the unstable than in the control knees. At 30° flexion, the tibial tubercle in the unstable knees rotated internally, but it was never within the normal range. CT scans taken in full extension and at 30° flexion seem to be of value for ascertaining the degree of tibial tubercle malposition during knee flexion in patellar instability.  相似文献   
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