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81.
C4d deposition in the walls of peritubular capillaries is considered the key phenomenon in the histopathological diagnosis of humoral, i.e. antibody-mediated, allograft rejection. We have earlier proposed that deposition of C3c in glomerular capillaries and simultaneous intravascular accumulation of macrophages in allografts with immediate or early humoral rejection indicates a potentially serious condition with very poor prognosis. The clinical outcome of 45 cadaveric grafts with this phenomenon among 1960 renal allografts transplanted at our centre during 1984-1999, and the recipients of the contralateral kidneys, was retrospectively evaluated. Graft failure occurred in 44/45 grafts within 3 weeks, with graft loss in 33/45 (77%) within 4 months and 37/45 (82%) within 1 year. From the contralateral kidneys, 5/33 (15%) were lost within 1 year. In a recent series of early biopsies, we recognised that of 13 cases showing C4d positivity in peritubular capillaries but lacking C3c in glomeruli, 10/13 (77%) were still functioning after 4 months. The mean number of CD68(+) macrophages per glomerular profile, i.e. the glomerular macrophage index, shows a significant difference between C4d(+)C3c(-) and C4d(+)C3c(+) cases (p<0.001). Our results indicate the existence of a clinically important subgroup of early humoral rejection with particular morphological features.  相似文献   
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OBJECTIVE: We sought to evaluate the usefulness of coronal and sagittal reformations from isotropic chest computed tomography (CT) examinations. METHODS: A total of 30 chest CT examinations were reconstructed into 2 sets of axial source images: 0.9-mm slice width with 0.45-mm reconstruction interval (isotropic) and 4-mm slices with 3-mm reconstruction interval. The isotropic dataset was reformatted into coronal and sagittal stacks with 4-mm slices. Three readers reviewed the image sets with 4-mm slice widths. Coronal and sagittal reformations were compared at the same sitting to axial images for depiction of anatomy and disease in the aorta, pulmonary arteries, hilar regions, mediastinum, lung parenchyma, pleura, diaphragm, thoracic spine, ribs, and trachea. A 5-point scale was used to determine whether nonaxial reformations showed anatomy and disease significantly better, somewhat better, same, somewhat worse or significantly worse than equivalent thickness axial source images. A 3-point scale was used to score if nonaxial image sets showed no, some, or significant additional information compared with the axial plane regarding the main diagnosis. RESULTS: There was better visualization of the hilar regions, diaphragm, spine, and trachea on the coronal reformations compared with source axial images (P < 0.05). Sagittal reformations scored better than axial source images for aorta, pleura, diaphragm, spine, and ribs (P < 0.05). The coronal and sagittal series showed significant additional information in 11% and 9% of patients, respectively. CONCLUSION: Radiologists should consider the use of one or both of coronal and sagittal planes in addition to the axial series in routine interpretation of chest CT.  相似文献   
84.
Background and Objective  The basis of blood group A1 and A2 phenotypes has been debated for many decades, and still the chemical basis is unresolved. The literature generally identifies the glycolipid chemical differences between blood group A1 and A2 phenotypes as being poor or no expression of A type 3 and A type 4 structures on A2 red cells, although this assertion is not unanimous.
Materials and Methods  Using purified glycolipids and specific monoclonal antibodies, we revisited the glycolipid basis of the A1 and A2 phenotypes. Purified glycolipids were extracted from four individual A1 and four individual A2 blood units. One blood unit from an A weak subgroup was also included. Monoclonal anti-A reagents including those originally used to define the basis of A1 and A2 phenotypes were used in a thin layer chromatography – enzyme immunoassay to identify the presence of specific glycolipids.
Results  A type 3 glycolipid structures were found to be present in large amounts in all phenotypes. In contrast, the A type 4 glycolipid structure was virtually undetectable in the A2 phenotype, but was present in the A1 and A subgroup samples.
Conclusion  The major glycolipid difference between the A1 and A2 phenotypes is the dominance of A type 4 glycolipids in the A1 phenotype.  相似文献   
85.
PURPOSE: The purpose of this study was to evaluate whether asthenopic symptoms in schoolchildren diagnosed with accommodative insufficiency (AI) and graded with the Visual Analogue Scale (VAS) could be correlated with the degree of accommodative deficiency in these children, and to investigate if VAS grading of the asthenopic symptoms could be used as an instrument to indicate the level of improvement of AI. METHODS: Forty-nine children (mean age 10.2 years +/- 2.7) diagnosed with AI graded their degree of asthenopia on the VAS before and after a 12-week treatment period wearing individually dispensed reading glasses. RESULTS: The improvement in accommodation after treatment was statistically significant (p < 0.001) and 83.7% of the children obtained normal accommodative amplitude in relation to age. The reduction in asthenopic symptoms as graded with the VAS was also statistically significant (p < 0.001) after treatment and 89.9% of the children obtained a normal VAS score. However, no correlation between the degree of accommodative deficiency and the VAS grading could be found, neither before nor after treatment. DISCUSSION: Based on these results we conclude that the visual analogue scale (VAS) cannot be used as an instrument to indicate the degree of accommodative deficiency nor can it be used to indicate the level of improvement during the course of treatment. However, the VAS can be used as an instrument to verify and document whether or not asthenopic symptoms are present, and therefore also to indicate when symptoms have been relieved.  相似文献   
86.
Two blood group O paediatric patients, 12 and 6 months old, were transplanted with liver segments from their blood group A2Le (a(-)b+) Se and blood group A1Le (a(-)b+) Se fathers, respectively. Recipient anti-A antibody titres were reduced prior to transplantation by blood exchange. Both patients had rejection episodes in the post-transplant period that were reversed by anti-rejection therapy. No anti-A antibody titre rise occurred concomitant with these rejections. Postoperatively both patients had cytomegalovirus (CMV) infections, and simultaneous with these infections, a strong increase in anti-A antibody titres was seen, but no rejection occurred. The anti-A antibody titre increase seemed to be specific for A antigens, because the anti-B and anti-alphaGal (anti-pig) antibody titres did not show any changes. CMV infection is a serious cause of morbidity and mortality in immunosuppressed patients, and the virus can influence glycosylation of infected cells. Whether this can explain the importance of the infection in relation to the increase in titre remains to be elucidated.  相似文献   
87.
AIMS: The relation between abnormal left ventricular (LV) diastolic filling and the extent of coronary atherosclerosis per se has not been described. We aimed to investigate the prevalence of impaired LV diastolic filling in patients with stable coronary artery disease (CAD) and its relationship to the number and location of coronary lesions visualized at coronary angiography. METHODS AND RESULTS: In 170 consecutive patients with stable CAD and an abnormal coronary angiogram we assessed LV diastolic filling by Doppler evaluation of the transmitral early to atrial peak flow velocity (E/A) and the systolic to diastolic ratio of the pulmonary venous peak inflow to the left atrium (S/D). Abnormal diastolic filling was defined as E/A < or =0.75, or E/A >1.0 combined with S/D < or =1.0, and was present in 41% of the patients. In patients with one-, two- and three-vessel disease the prevalence of impaired diastolic filling was 27, 30 and 49%, respectively (P = 0.026). In multiple logistic regression analysis diastolic filling was independently correlated with the number of stenotic coronary vessel areas. CONCLUSION: In patients with stable angiographically verified CAD, the prevalence of impaired diastolic filling was 41%. The prevalence increased with an increasing number of stenotic coronary artery areas independent of other variables tested, including prior myocardial infarction, LV systolic function and mitral regurgitation.  相似文献   
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89.
Natural Antibodies and Human Xenotransplantation   总被引:7,自引:0,他引:7  
  相似文献   
90.
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