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71.
JD Amsterdam F Garcia-Espana J Fawcett FM Quitkin FW Reimherr JF Rosenbaum C Beasley 《Canadian Metallurgical Quarterly》1999,19(1):9-14
PURPOSE: To evaluate the potential diagnostic role of mediastinal sonography in patients with cystic fibrosis (CF), we screened the mediastinum of adult CF patients with and without signs of infection and healthy controls. METHODS: Fifty-four consecutive adult patients with CF and 53 healthy volunteers underwent high-resolution mediastinal sonography. The paratracheal region and aorticopulmonary window of each subject were examined for lymph nodes. Each patient was screened for clinical signs of infection. RESULTS: Lymph nodes were detectable in the mediastinum of 39 of 50 CF patients (78%); the mean total lymph node volume was 1.5 +/- 1.7 cm3. Lymph nodes were detectable in the mediastinum of 31 of 50 controls (62%); the mean total lymph node volume in this group was 0.3 +/- 0.3 cm3 (p < 0.001). In the 30 CF patients with signs of infection, the mean total lymph node volume was larger (2.0 +/- 1.8 cm3) than in the 20 CF patients without signs of infection (0.7 +/- 0.9 cm3; p = 0.002). CONCLUSIONS: These results indicate that lymph node volume determination by high-resolution mediastinal sonography may help assess inflammatory activity in patients with CF. 相似文献
72.
Immunization with a particulate fraction of blood-stage antigens was shown previously to protect mice against Plasmodium yoelii malaria. To identify antigens inducing the protective response, sera from immunized mice were used to screen a P. yoelii cDNA expression library. Sequence analysis of one 2.6-kb cDNA clone indicated that the identified gene, pypag-1, encoded a novel plasmodial antigen. Two nonoverlapping regions of pypag-1 were expressed in Escherichia coli. The first recombinant antigen, pAg-1N, contained the N-terminal 337 residues, which included a putative transmembrane domain and a region relatively rich in tryptophan residues. The second recombinant antigen, pAg-1C, contained the remaining C-terminal 211 residues, which included 31 copies of a 5-amino-acid degenerative repeat. Immunoblot studies using rabbit antiserum raised against recombinant pAg-1N showed that the native pypAg-1 protein migrated at approximately 98 kDa, considerably slower than its predicted molecular mass of 66 kDa. Immunofluorescence studies localized the expression of the native pypAg-1 protein both to the cytoplasm and at the surface of P. yoelii-infected erythrocytes. Immunization with either pAg-1N or pAg-1C induced a four- to sevenfold reduction in P. yoelii blood-stage parasitemia. As such, pypAg-1 appears to contain at least two distinct protective epitopes. To our knowledge, this is the first characterization of a protective antigen of P. yoelii that is associated with the erythrocyte membrane. 相似文献
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