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BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases.  相似文献   
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Recently, monoclonal antibodies capable of phenotyping malignant lymphomas in routinely fixed and processed tissue have become available. Some of these reagents identify lineage-restricted variants of the leucocyte common molecule, whereas others identify unique fixation-resistant epitopes on lymphoid cells, some of which are shared by non-lymphoid tissues. A new generation of antibodies recognizing 'classical' leucocyte antigens such as CD3 are also emerging. Refinements in antigen detection systems, especially for immunoglobulin recognition, combined with these new reagents promise to improve the accuracy of lymphoma diagnosis in routine histopathology. These new antibodies are reviewed, and their limitations, cross reactivities and profiles of staining in lymphoreticular disease are discussed. A strategy for their optimal use is proposed.  相似文献   
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We studied 11 cases of malignant lymphoma diagnosed concurrently with or following lymph node infarction. Cases included seven B-cell lymphomas, three T-cell lymphomas, and one case of Hodgkin's disease. Sections of viable and infarcted tissue were immunostained in parallel using a panel of antibodies effective in routinely processed, wax-embedded tissue. The panel included anti-leucocyte-common antigen (CD45), T-cell-associated antigens (UCHL1, MT1), B-cell-associated antigens (MB1, 4KB5 (CD45R), MT2, LN1), a B-cell-specific antigen (L26), C3D-1 (CD15), and BER-H2 (CD30). Antibodies to intermediate filament cytoskeletal proteins, epithelial membrane antigen, and Factor VIII-related antigen were also used. In eight cases, staining of the infarcted material gave evidence of a lymphoid proliferation of either T- or B-cell type; an in the case of Hodgkin's disease, the results supported this diagnosis. The immunophenotype derived in the infarcted tissue mirrored the findings in the viable material in these eight cases of non-Hodgkin's lymphoma. A case of testicular infarction with concurrent intraosseous lymphoma was also examined. Staining in this case provided evidence of infarcted lymphoma. Thus, immunostaining of infarcted lymphoid tissue with these novel antibodies provides valuable information that conventional light microscopy cannot offer.  相似文献   
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Over a 13-month period, 14 patients with proximal tubal obstruction underwent transcervical fallopian tube recanalization under fluoroscopic guidance in an outpatient setting at the hospital of the University of Pennsylvania. Twenty-one of 24 attempted tubal dilations (87.5%) were successful, as demonstrated by tubal opacification and contrast spillage into the peritoneal cavity at the conclusion of the procedure. Four intrauterine pregnancies, and no ectopic pregnancies, have followed the recanalization. One pregnancy ended in an early miscarriage, one patient delivered a healthy term female, and two pregnancies are ongoing at greater than twenty weeks' gestation. Two procedure-related complications occurred: in one patient, the isthmic segment of a fallopian tube was perforated, but healed without incident, and another patient experienced a low-grade fever, which resolved with p.o. antibiotics. We therefore conclude that fallopian tube recanalization is a well-tolerated, safe, and effective procedure for the treatment of proximal tubal occlusion.  相似文献   
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BACKGROUND AND CONTEXT: The functional recovery of animals subject to experimental spinal cord injury (SCI) is dependent on the injury model as well as the species and strain of animal used. Previous studies have shown differences in rates and degree of recovery between rats of different strains. PURPOSE: We sought to explore the hypothesis that differences in gene expression are associated with differences in functional recovery. STUDY DESIGN/SETTING: Laboratory study involving cohorts of three different strains of rat. METHODS: We used the Impactor device to produce identical spinal cord contusion injuries in groups of Long Evans, Sprague-Dawley, and Lewis rats (10 each). The functional recovery of animals was assessed using the Basso, Beattie, and Bresnahan rating scale. Six weeks after injury, rats were killed and the spinal cords were harvested for deoxyribonucleic acid microarray analysis. Changes in gene expression compared with intraspecies controls (3 each) were assessed at the region of injury and at a rostral segment of the spinal cord. Selected genes were also studied with real-time polymerase chain reaction. RESULTS: We found that different strains tended to exhibit different patterns of functional recovery. There were differences between the strains in terms of gene expression. CONCLUSIONS: These results emphasize the importance of testing novel therapies for SCI in a variety of animal species before introduction into human trials. Further research into the influence of several gene products on functional recovery is needed.  相似文献   
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Tissue sections embedded in paraffin and fixed in formalin from 32 patients with Hodgkin's disease, representing the major histological subtypes, were studied using two granulocyte specific monoclonal antibodies (Leu-M1 and 3C4) and an HLA-D region specific monoclonal antibody (TAL-IB5). Reed-Sternberg cells were stained with one or other of the antigranulocyte antibodies in the nodular sclerosing and lymphocyte depleted subtypes. Reed-Sternberg cells in all but three cases of mixed cellularity Hodgkin's disease were positive with both Leu-M1 and 3C4. One case stained with only Leu-M1, and two cases were consistently negative with both antibodies. HLA-DR was widely expressed in the Reed-Sternberg cells of all three subtypes. In the four cases of lymphocyte predominant Hodgkin's disease the multinucleated Reed-Sternberg cells did not stain with either antigranulocyte antibody but were strongly positive with anti-HLA-DR. Twenty five cases of non-Hodgkin's lymphoma, in which there were multinucleated giant cells resembling Reed-Sternberg cells, were studied in a similar way. These cases included pleomorphic T cell and B cell lymphomas, histiocytic lymphomas, and malignant histiocytosis of the intestine. In none of these did the multinucleated cells stain with either antigranulocyte antibody, but in most cases the multinucleated cells stained with anti-HLA-DR. In two cases of the tumour stage of mycosis fungoides dot like intracytoplasmic staining was shown in the tumour cells with both antigranulocyte markers. The monoclonal antigranulocyte antibodies Leu-M1 and 3C4 are of considerable value in both the diagnosis and the differential diagnosis of Hodgkin's disease and are particularly valuable in that they can be applied to tissue fixed in formalin and embedded in paraffin. Antibody to HLA-DR, while useful, is of less value.  相似文献   
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Summary Most series in Africa show a high percentage of hepatitis B surface Hepatitis antigen in hepatocellular carcinoma. Two groups of cases were investigated in this study. The one was derived from the autopsy material at Baragwanath hospital from subjects who had lived in Soweto, a large Black urban town. The second group consisted of male Black mineworkers generally originating from rural areas. A combination of the aldehydefuchsin stain and immunoperoxidase technique was used. The two groups showed totally different results. The Baragwanath series consisted of 24 hepatocellular carcinomas of which only 4 (17%) were HBsAg positive. Of the 24 cases, 14 had cirrhosis of which 9 were macronodular and 5 micronodular. Ten of these cases showed heavy iron overload. The series of male Black mineworkers comprised 22 cases of which 16 (72%) were HBsAg positive. Twelve of the 22 cases showed a macronodular cirrhosis and there were no micronodular cirrhoses. Only one case showed severe iron overload. These findings delineate two different populations of hepatocellular carcinoma in Southern Africa.  相似文献   
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