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排序方式: 共有531条查询结果,搜索用时 15 毫秒
1.
Veronique Braud E. Yvonne Jones Andrew McMichael 《European journal of immunology》1997,27(5):1164-1169
Human histocompatibility leukocyte antigen E (HLA-E) and mouse major histocompatibility complex (MHC) class Ib antigen, Qa-1, share the same substitutions at two normally conserved positions 143 and 147, which are likely to affect binding of the C terminus of peptides. Qa-1 is able to bind a peptide derived from the leader sequence of H-2 D and H-2 L molecules. We developed a peptide binding assay in vitro to compare the binding specificity of HLA-E with the mouse MHC class Ib molecule Qa-1. We demonstrate that HLA-E binds, although poorly, the peptide which binds to Qa-1 and that it also binds nonamer signal sequence-derived peptides from human MHC class I molecules. Using alanine and glycine substitutions, we could define primary anchor residues at positions 2 and 9 and secondary anchor residues at position 7 and possibly 3. 相似文献
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The effect of chemical shift on magnetic resonance (MR) imaging of the pituitary fossa was studied. Healthy volunteers underwent conventional MR imaging of the pituitary fossa and then imaging with the frequency-encoding gradient reversed or with the phase- and frequency-encoding gradients interchanged. Comparison of the image pairs in each subject showed that the thin, black stripe evident at the water-fat interface within the pituitary fossa was altered when the gradients were changed. Therefore, the low-intensity signal within the pituitary fossa is a chemical shift misregistration effect. 相似文献
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Anulus fibrosus in bulging intervertebral disks 总被引:1,自引:0,他引:1
In this investigation the association of radial tears of the anulus fibrosus and bulging of the intervertebral disk was studied. An index of disk bulging was measured in sagittal anatomic sections in 149 lumbar disks from 31 cadavers. The indexes of disk bulging were correlated with stages of disk development and the presence of an annular tear. The largest disk-bulging indexes were always associated with radial tears of the anulus. Eighty-four percent of the disks with radial tears had disk-bulging indexes greater than 2.5 mm. Most normal adult disks had an index of less than 2.5 mm. The results challenge the concept that the anulus fibrosus is intact in bulging disks, although ruptured in herniated disks. 相似文献
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P Pfitzenmeyer P Foucher F Piard B Coudert M L Braud P Gabez S Lacroix J P Mabille P Camus 《Thorax》1992,47(8):622-627
BACKGROUND: Nilutamide is a new, specific synthetic antiandrogen, released in several countries for the treatment of metastatic carcinoma of the prostate. Eight patients at the University Medical Centre at Dijon and affiliated referring hospitals developed reversible pulmonary opacities and respiratory symptoms while taking the drug. METHODS: Records of eight patients who developed new, otherwise unexplained chest opacities while taking nilutamide were reviewed. In each patient a careful aetiological search was made for other environmental or endogenous causes. Six patients underwent bronchoalveolar lavage, and lavage fluid was cultured. Corticosteroids were not given, unless gas exchange was compromised (two patients). RESULTS: The eight patients (all male) had had carcinoma of the prostate diagnosed on average 10.2 months earlier. All had improved with nilutamide, with a dramatic decrease of prostate specific antigen levels. Seven had received nilutamide at the recommended dosage of 150 mg/day, and one had received twice that amount. Treatment had lasted on average 113 (range 10-225) days, and the mean cumulated exposure was 21.8 (3-38) grams. The chest radiographs showed bilateral infiltrates, with no consistent topographic predilection. A restrictive lung defect was present in six patients and hypoxia in all (mean arterial oxygen tension (PaO2) 6.6 kPa). Bronchoalveolar lavage showed lymphocytosis in four patients and neutrophilia in two. The outcome was favourable in all patients after they had stopped nilutamide only (five patients), with corticosteroids (two patients) or a simple reduction of nilutamide from 300 to 150 mg/day (one patient). Recovery was associated with improvement of pulmonary function and PaO2. CONCLUSION: Nilutamide is associated with interstitial pneumonitis in about 1% of patients and appears reversible. 相似文献
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Sanjana VM; Johnston PA; Robertson CR; Jamison RL 《The American journal of physiology》1976,231(2):313-318
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Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献