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41.
The humoral immune response against human cytomegalovirus (HCMV) was evaluated in immunocompromised patients by Western blotting (WB) based on recombinant viral envelope (gB and gH) and tegument (pp150 and pp65) proteins. Three groups of patients were investigated: (a) 74 renal transplant recipients; (b) 24 hemodialysis patients, both groups without clinical evidence of viral infections; and (c) 19 renal transplant patients with manifest HCMV infections. The results obtained suggest that (i) the WB is considerably more sensitive, recognizing the HCMV-specific IgM response rather than the enzyme-linked immunosorbent assays. An IgM response was detected in one-third of all clinically asymptomatic renal patients. (ii) The virus-specific IgM response is primarily directed against the pp150 epitope. (iii) In patients with clinically manifest HCMV disease, additional IgM reactivities are most frequently directed against the glycoprotein B epitope. (iv) The severity of HCMV infections correlates with the extent of the IgM antibody response, i.e. with the number of specific epitopes involved. (v) After transplantation, IgM reactivity and its epitope-specific pattern persist for years.  相似文献   
42.
Summary We present a case with a characteristic magnetic resonance image (MRI) of bilateral open-lipped schizencephaly and atypical clinical presentation. The patient is still alive and in good health in her forties, she has never presented seizures, and although the motor dysfunction is well correlated with cerebral lobe involvement, neurobehavioral dysfunction is not proportional to the MR image of the cerebral malformation.
Un cas inhabituel de schizencéphalie bilatérale
Résumé Nous présentons un cas de schizencéphalie bilatérale ouverte caractérisé par une présentation clinique atypique et une imagerie par résonance magnétique nucléaire caractéristique. La patiente est encore vivante, en bonne santé, à plus de 40 ans, elle n'a jamais présenté de crise comitiale et, bien que les troubles moteurs soient bien corrélés aux altérations cérébrales, les troubles neuro-comportementaux ne sont pas proportionnels aux images IRM de cette malformation cérébrale.
  相似文献   
43.
The presence and localization of antigenic sites in glomeruli of 14 patients with acute poststreptococcal glomerulonephritis (AGN) were studied by immunofluorescein and immunoferritin technics. Labeled IgG fractions from the same patients were used for the identification of antigenic sites. The staining capacity of these IgG fractions depended on the time when sera were obtained. Staining was minimal during the first week, and increased up to the fourth or fifth week. Glomeruli, however, stained only when renal tissue was obtained during the early phase of the disease. Precise localization of antigenic sites was determined with ferritin-conjugated patients' IgG. Segmental deposition of ferritin was observed in the mesangial matrix and on the endothelial side of the glomerular basement membrane. Subepithelial electron-dense deposits contained no or very few ferritin particles. In contrast, ferritin-conjugated antihuman IgG was distributed diffusely in the mesangial matrix, on the endothelial side of the basement membrane and in subepithelial deposits. These findings suggest that, during the early stage of acute poststreptococcal glomerulonephritis, free antigen is present in the glomeruli of patients with this disease.  相似文献   
44.
Experimental and histological studies on the reaction of surrounding gingiva to permucosal implants of dense calcium hydroxyapatite were carried out in dogs. Epithelial attachment and connection of supra-alveolar collagen fibres to the implant surface seemed to form a biological seal around implants similar to that around natural teeth. However, excellent oral hygiene is very important for the maintenance of this biological seal.  相似文献   
45.
AIMS: To clarify the nature (reactive or neoplastic) of lesional, perifocally aggregated lymphocytes in bone marrow infiltrates of systemic mastocytosis (SM), the histopathology of which can resemble malignant lymphoma with focal bone marrow involvement, particularly low grade malignant B cell lymphoma of lymphoplasmacytic immunocytoma subtype, which frequently exhibits increased mast cell (MC) numbers. METHODS: Thirteen cases of SM and three of lymphoplasmacytic immunocytoma with predominant focal bone marrow infiltration were investigated. Immunostaining of formalin fixed, paraffin wax embedded bone marrow specimens was performed using antibodies against CD2, CD5, CD20, CD23, and CD25; kappa and lambda immunoglobulin light chains; and MC markers chymase, tryptase, and CD117 (KIT). Monoclonal rearrangements of IgH and TCRgamma were studied using seminested polymerase chain reaction (PCR). c-kit point mutation Asp816-Val was detected by PNA mediated PCR clamping and hybridisation probes. RESULTS: The lymphocytic clusters in SM contained nearly equal numbers of mature T and B cells, the latter with no coexpression of aberrant antigens, such as CD5 or CD23. Most MCs in SM cases constantly coexpressed tryptase, CD25, and CD117. No monoclonal rearrangements were seen for IgH or TCRgamma. In contrast, B cells from immunocytomas showed light chain restriction and monoclonal rearrangement for IgH, confirming their neoplastic nature. c-kit point mutation Asp816-Val was found in ten of 13 SM cases, but in none of the three immunocytomas. CONCLUSIONS: Focal accumulations of lymphocytes in the bone marrow of SM are reactive in nature and could be termed lymphocytosis. A diagnosis of SM-AHNMD/immunocytoma should not be made.  相似文献   
46.
Symptoms of two groups of Systemic lupus erythematosus (SLE) (Group 1 constituted 65 patients examined from 1975 to 1981; Group 2 constituted 104 patients examined from 1980 to 1988), which were diagnosed according to the American Rheumatism Association (ARA) preliminary criteria, were statistically analyzed with the use of a package of statistical programs which included computation of a matrix of correlation and cluster analysis. In both groups similar frequency and associations of SLE symptoms were seen. Hence, there was a positive correlation between kidney involvement and hematological abnormalities with nDNA Abs what was a hallmark of a severe SLE. In contrast, the symptoms of severe SLE disease was rarely seen in cases with Raynaud's phenomenon and discoid lesions. Our cluster analysis further distinguished groups on the basis of renal involvement, skin symptomatology, and polyserositis. These results also were similar in both groups of patients. That gave further credence to our results and continued to support the concept of SLE variants being distinguished on the basis of the clinical picture.  相似文献   
47.
Lewis antigens in normal and neoplastic urothelium.   总被引:3,自引:1,他引:3       下载免费PDF全文
The Lewis (Lea and Leb) antigens are closely related to the A, B, H blood group antigens and have been demonstrated in several secretory epithelia, but their expression in nonsecretory cells has not been studied systematically. This report provides detailed data on the expression of Lea and Leb in normal and neoplastic urothelium. The authors have examined multiple biopsy specimens of normal bladder mucosa and transitional cell carcinomas (TCCs) from 74 patients whose red blood cells (RBCs) were also typed for A, B, H, Lea, and Leb antigens and have correlated tissue antigen detectability with the RBC phenotype and the cytologic grade of malignancy. Antisera of human and animal sources were used in a modified red cell adherence test (RCA), and multiple controls were employed for determination of the specificity of the reactions. Both fresh-frozen and paraffin-processed tissues were examined from each patient. Paraffin processing as well as treatment with ethanol significantly suppressed the tissue reactions. Ninety-four percent of normal mucosa specimens and 73% of TCCs gave positive reactions with both anti-Lea and anti-Leb sera. Abnormal patterns of Lewis reactivity were observed in 43% of Grade III or IV and in 14% of Grade I or II TCCs. Although there was no direct correlation between A, B, H reactivity and Lewis reactivity, all TCCs which had abnormally low reactivity for both the expected Le and A, B, or H antigens were of high grade and invasive.  相似文献   
48.
49.
A new commercially developed cytomegalovirus (CMV)-IgM ELISA was found to be sensitive and specific when compared with sucrose gradient fractionation of Ig classes in CMV antibody-positive and negative sera. The presence of CMV IgM in patients' sera correlated with positive virus isolation from circulating mononuclear blood cells and urine. Serial examinations of patients with primary or recent CMV infection revealed a typical sequence of IgM and IgG development. The frequency of CMV isolation declined as the concentration of IgM decreased and the IgG levels increased. Since the isolation of CMV from clinical specimens is a cumbersome procedure, we suggest that the IgM ELISA could provide rapid and valuable information on the presence of an active or reactivated CMV infection.  相似文献   
50.
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