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271.
The value of DNA hybridisation (using immunoglobulin and T cell receptor gene probes) was assessed during the diagnosis of problematical lymphoid tissue biopsy specimens. In 14 of 18 specimens (78%), which contained a malignant lymphoproliferation of uncertain aetiology, this technique permitted the demonstration of a monoclonal proliferation of B cells (nine cases) or T cells (five cases). In five further lymph node biopsy specimens, in which the differential diagnosis lay between a reactive or malignant process, a clonal proliferation was shown in three cases. DNA analysis is, therefore, of practical value in resolving many of the diagnostic problems that arise in the assessment of lymphoid tissue biopsy specimens.  相似文献   
272.
The value of immunohistological labeling with a panel of monoclonal antibodies in the diagnosis of routinely processed surgical biopsies has been assessed. The cases examined consisted of an unselected series of tumor biopsies referred during a 12-month period because of doubt as to the nature of the neoplasm and are representative of the type of diagnostic problem regularly encountered in routine surgical pathology. In 30 of the 38 cases studied, reactivity with monoclonal antileukocyte antibody (and nonreactivity with monoclonal antiepithelial antibodies) indicated that the tumor was a lymphoma. Seven of the remaining eight cases gave the reverse reaction pattern and therefore were classified as carcinomas, while one biopsy was unreactive with all antibodies. Review of the clinical details in each case showed that the clinical management in several instances was influenced by establishing the correct diagnosis and it therefore is suggested that immunohistologic examination should be used more widely in the study of tumors that give rise to diagnostic difficulty.  相似文献   
273.
The clinical, morphologic, and immunohistochemical features of 5 cases of peripheral T-cell lymphoma with lymph node and skin involvement are reported. All patients were male and presented with generalized lymphadenopathy and skin lesions. Lymph node biopsy specimens showed a diffusely growing, pleomorphic, atypical lymphoid infiltrate composed of markedly irregular small and large cells. The stroma consisted of plasma cells, eosinophils, epithelioid histiocytes, and an increased number of small blood vessels. A similar neoplastic infiltrate was observed in the cutaneous nodules that developed in three patients. Immunohistochemistry on frozen tissue sections of lymph nodes using a broad panel of monoclonal antibodies revealed that the neoplastic cells were reactive with anti-T-cell antibodies, the majority of them belonging to the helper/inducer T-cell subset. Stromal plasma cells contained polyclonal immunoglobulins. It is concluded that the malignant lymphoma of peripheral helper/inducer T-cell origin observed in these five patients represents a variant of a mixed, blastic/cell T-cell lymphoma, characterized by a peculiar stromal component and skin involvement.  相似文献   
274.
Two monoclonal murine antibodies have been raised against a delipidated extract of human cream. These antibodies were detected by immunohistological screening of hybridoma culture supernatants on sections of human breast tissue. One of those antibodies (E29) was subsequently screened against a range of normal and neoplastic human tissues and shown to react with a wide variety of human epithelia and with mesothelial cells. Antibody E29 was unreactive with other cell types, with the exception of occasional plasma cells. Antibody E29 is suitable for use on paraffin embedded tissue and represents a valuable reagent for the identification of tumours of epithelial origin.  相似文献   
275.
Polyclonal rat antisera, raised against affinity purified CD3 antigen, gave strong immunoenzymatic labelling of T cells in routine paraffin embedded sections, with negligible background staining. The specificity of these reactions was confirmed by staining biopsy specimens from 21 previously phenotyped non-Hodgkin's lymphomas (including 14 of T cell origin and six of B cell origin). It is suggested that the ability of the polyclonal anti-CD3 antisera to detect T cells in paraffin sections is due to the presence in these sera of antibodies against fixation resistant epitopes on CD3 antigen, and that immunisation with purified denatured preparations of other white cell associated antigens may broaden the range of antibodies suitable for the phenotypic analysis of leucocytes in routine histological samples.  相似文献   
276.
To assess the short and longterm efficacy of intensive inpatient treatment of active rheumatoid arthritis (RA), 16 patients, the test group, admitted to a hospital based rheumatic disease unit (mean length of stay 12.4 days) were studied, using clinical and laboratory variables. The comparison group was similarly evaluated, using 10 outpatients with active RA to whom hospitalization was recommended, but refused by the patients. Both groups were studied intensively over a 12-week period. In addition, a 2-year followup was performed on 12 test group inpatients and 8 comparison group outpatients, using the same variables plus a functional status questionnaire. Health care costs were determined for both groups and corrected for a 1985 dollar value. The test group showed significant improvement in morning stiffness, pain, and joint score, whereas the comparison group improved only in pain score during the initial 12-week period. At 2 years, the test group and the comparison group showed significant improvement in morning stiffness, pain, grip strength, and joint score. The comparison group initially had a somewhat lower index of disease activity. The test group maintained their initial improvement and none required rehospitalization. Functional status scores were similar for both groups. Health care costs were initially higher for the test group ($5,065); followup care cost for the test group was $99 less/year than the comparison group over 2 years. Hospitalization on a rheumatic disease unit brought about prompt, sustained improvement in 2 weeks which required nearly 2 years to achieve in the comparison group. Such hospitalization of uncomplicated RA seems warranted to decrease disability and increase the quality of life.  相似文献   
277.
Several in vitro studies stress a potentially important role of interleukin 4 (IL-4) and the related gp200-MR6 molecule in the immunological response to cancer and in tumour proliferation. In the present study, we assessed the expression of gp200-MR6 in primary breast cacrinomas using the MR6 monoclonal antibody. Results were correlated with tumour parameters (T-,N-stage, histology, grade, oestrogen and epidermal growth factor (EGF) receptors), and the impact on survival was assessed. Twenty-four out of 110 cases (22%) were positive for gp200-MR6, 62 out of 110 (56%) expressed weak staining and 24 out of 114 (22%) did not stain. The normal breast epithelia were invariably stained for gp200-MR6 showing that down-regulation or loss of this molecule occurred during the evolution of breast cancer. Gp200-MR6 loss was independent from differentiation, nodal positivity and oestrogen receptor levels as well as patients'' age. Loss of the gp200-MR6 molecule was more frequent in lobular cases (P=0.03). The overall survival was better, although not reaching statistical significance, in patients with positive gp200-MR6 expression (92% alive at 5 years compared with 70% for those with weak or no expression, P=0.1). The local relapse-free survival was independent of gp200-MR6 status. It is concluded that loss of gp200-MR6 may be one of the mechanisms through which breast cancer cells escape immune surveillance, resulting in an increased metastatic potential and poorer outcome. Evidence of down-regulation of the gp200-MR6 molecule has implications for IL-4-linked toxin therapy and, as IL-4 is an inhibitor of breast epithelial growth, may represent loss of a tumour-suppression mechanism.  相似文献   
278.
AIM: To examine tumour samples immunohistochemically for MUC1 (episialin), epidermal growth factor receptor (EGFR), and c-erbB-2, since the disruption of the cell-cell adhesion system by MUC1 and the c-erbB oncoprotein family is known to be important in the development of metastasis in human cancers. METHODS: 93 tumour samples from patients with early stage non-small cell lung cancer treated with surgery alone were examined for episialin, EGFR, and c-erbB-2. RESULTS: Episialin depolarised expression did not correlate with any of the histopathological variables examined (T,N stage, grade, histology, Ki67 proliferation index). No correlation was observed between episialin and EGFR or c-erbB-2 expression. Survival analysis showed that episialin depolarised expression correlated with poor prognosis (p = 0.003), especially in squamous cell cases (p = 0.0003). Episialin expression defined a group of patients with poor prognosis in the node positive category (p = 0.003). In multivariate analysis episialin was the most significant independent prognostic factor (p = 0.007), followed by N stage (p = 0.04). CONCLUSIONS: Depolarised expression of episialin is associated with poor outcome in early stage non-small cell lung cancer. Despite the similar activity on the cadherin cell-cell adhesion system, the expression of episialin and c-erbB oncoproteins is likely to be activated within different pathogenic pathways.  相似文献   
279.
AIMS--To provide a detailed knowledge of the distribution of the CD13 molecule, also known as the protease aminopeptidase-N, on both normal tissues and malignant neoplasms of epithelial and lymphoid origin. METHODS--CD13 antigen was examined by immunocytochemistry, using a recently produced antibody (VS5E) alongside a commercially available anti-CD13 monoclonal antibody. The VS5E recognising CD13 was produced by immunising a doxorubicin resistant breast cancer cell line (MCF-7-ADr). A striking feature of this antibody was that it stained the doxorubicin resistant cells but not the parental cell line. Both antibodies were tested on a broad range of normal tissues and three common types of epithelial malignancy (colon n = 28, lung n = 30, breast n = 35), and 12 cases of Hodgkin''s and 52 of non-Hodgkin''s lymphomas. RESULTS--CD13 was expressed on many tissue and cell types outside the haematopoietic system. In particular it was present on breast epithelium and in 20% (seven of 35) of breast carcinomas, but absent in normal and neoplastic colonic and bronchial tissues and lymphomas. CONCLUSIONS--This study provides not only detailed information about the expression of the CD13 antigen, but also raises the important possibility that CD13 expression may correlate with drug resistance in breast carcinomas.  相似文献   
280.
The expression of thymidine phosphorylase (TP), a potent chemotactic factor for endothelial cells, was studied in 60 adenocarcinomas of the gallbladder, by use of immunohistochemical techniques. Results on patterns of TP expression were correlated with angiogenesis (anti-CD31), histopathological variables, and patient survival. TP was frequently expressed in tumor cells, stromal cells, tumor-associated macrophages, and lymphocytes of gallbladder adenocarcinomas. The expression was mixed nuclear/cytoplasmic. However, only nuclear TP (TPnuc) expression by tumor cells was correlated with increased angiogenic activity. High angiogenesis, assessed as microvessel density (MVD), was the most significant prognostic factor. The subgroup of patients with TPnuc and medium/high MVD had the worst prognosis as evaluated by the survival curves. Furthermore, CD31+ lymphocytes, frequently seen in carcinomas with high-fibroblastic TP reactivity, were connected with an improved survival. It is concluded that angiogenesis, as verified by multivariate analysis, is the most important prognostic factor in gallbladder carcinomas. In these tumors, high histologic grade and low CD31+ lymphocytic infiltration are also independent predictors of poor prognosis. TP is associated with an aggressive phenotype apparently because of its anglogenic activity. Therapeutic strategies targeting TP may be of value in patients overexpressing this enzyme.  相似文献   
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