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BACKGROUND: The role of chest CT scan in the assessment of patients with hemoptysis is uncertain. AIM: To evaluate the usefulness of CT scan in patients with non massive hemoptysis. PATIENTS AND METHODS: Ninety six patients, 60 male, aged 23 to 76 years old, who presented with hemoptysis to an University Hospital, were studied. All patients were studied with a chest radiograph, a fiberoptic bronchoscopy and a high resolution CT scan. RESULTS: The final causes of hemoptysis were bronchiectasis in 27 cases, bronchogenic carcinoma in 24 cases and lung infections in nine. The source of bleeding was not identified in 18 patients (19%). CT scan clarified abnormalities seen in the chest radiograph in 30 patients (31%) and provided new diagnostic information in 13 (14%). CT scan correctly localized the source of bleeding found by fiberoptic bronchoscopy in 35 of 43 patients (81%), whereas chest radiograph did so in 27 (77%). All patients with bronchogenic carcinoma were identified by chest radiograph or bronchoscopy. Twenty of the 27 patients with bronchiectasis had radiological abnormalities in the chest radiograph. In only two patients, with lung metastases and non conclusive chest radiograph and bronchoscopy, CT scan provided information that significantly modified clinical management. CONCLUSIONS: CT scan was useful to stage patients with bronchogenic carcinoma and to assess the extension of bronchiectasis, but its impact in the management and clinical evolution of patients was limited. Therefore we do not recommend the routine use of CT scan in the assessment of patients with hemoptysis.  相似文献   
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Lipidation at the N-terminal of recombinant outer surface protein A (rOspA) is an important determinant of its immunogenicity. Lipidation patterns of rOspA can be sensitive to processing environments and storage conditions. In order to assure product consistency and stability. it is essential to characterize and monitor lipidation patterns of rOspA through its life-cycle. Electrospray mass spectroscopy combined with maximum entropy calculation was employed to analyze the lipidation of rOspA. The results revealed that more than 90% of protein is a tri-lipidated rOspA and the remainder is di-lipidated. It was demonstrated that the method is both sensitive and quantitative and has the potential to be used for routine quality control and stability testing.  相似文献   
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The specific binding of the lambda N protein to a 15 nucleotide RNA oligomer that forms a hairpin structure has been investigated by biophysical methods. Using fluorescence spectroscopy and equilibrium ultra-centrifugation, it was found that the N protein binds specifically to this RNA hairpin as a monomer. Circular dichroism experiments show that both the N protein and the RNA hairpin undergo structural change upon association of the complex.  相似文献   
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