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91.
Marginal zone B-cell lymphomas (MCL) of extranodal, nodal and splenic origin appear to be different lymphoma entities with a similar growth pattern in the marginal zone of the B-follicles. Decisive for the detection of MCL as a distinct lymphoma entity was the "MALT concept" for lymphoid infiltrates in the gastric and intestinal mucosa as described by Isaacson et al. in the 1980's. Immunohistological stainings for the immunoglobulin light and heavy chains and molecular pathological studies of the immunoglobulin heavy chain gene configuration have subsequently confirmed the neoplastic nature of the extranodal infiltrates and differentiated marginal zone cells from mantle zone cells. In 1994, the MCL of MALT type as well as of nodal and splenic origin were included in the REAL classification and in 1998 in the new WHO classification for lymphomas. Meanwhile extranodal MCL of MALT-type have been observed in almost every organ and site of the body, by far most frequently in the gastric mucosa. Beside the typical growth pattern, lymphoepithelial lesions are a distinct diagnostic feature of extranodal MCL. Clinically, the small cell extranodal MCL show a very good prognosis with regression after treatment. As for nodal and splenic MCL, we need further studies to evaluate the prognostic aspects and to compare them with other B-cell lymphomas. The same is true for primary extranodal large B-cell lymphomas or blastic transformation to a large cell lymphoma; in these tumors the diagnosis of a MALT type lymphoma should only be made if a small cell component with MALT-specific criteria can be proved.  相似文献   
92.
OBJECTIVE: Gynecologic disease is common in HIV-infected women. We examine the sociodemographic, clinical, and provider factors associated with the care of women with vaginal symptoms. METHODS: Women enrolled in the HIV Cost and Services Utilization Study (HCSUS), a nationally representative probability sample of HIV-infected adults, were interviewed between January 1996 and April 1997. Women with vaginal symptoms who sought medical attention were asked, "Did your health care provider examine your vaginal area?" Women were also asked if they received medication for their symptoms. RESULTS: Among 154 women with vaginal symptoms, 127 sought care for their symptoms. Of those who sought care, 48% saw a gynecologist and 52% sought care from nongynecologists, most often their usual HIV care provider. Women who saw a gynecologist for their symptoms were more likely to have received a pelvic examination (92% versus 76%; p =.06) and vaginal fluid collection (98% versus 88%; p =.06) than those who saw their regular HIV provider. Fifteen percent of women received medication for their symptoms without having a pelvic examination; gynecologists were less likely to prescribe without an examination (8% versus 21%; p =.12). CONCLUSION: Gynecologists are more likely to provide adequate care of vaginal symptoms among HIV-infected women than nongynecologists who were HIV care providers. This specialty difference is consistent with quality of care studies for other medical conditions, but the potential gynecologic complications of inadequate evaluation and treatment warrants further investigation.  相似文献   
93.
Twenty-eight cases of cutaneous T cell lymphomas of mycosis fungoides type, 8 of which showed a marked epidermotropism, were investigated for their reactivity with the monoclonal antibody HML-1. This reagent selectively recognizes human benign and malignant intestinal T lymphocytes, but not benign or malignant lymph node T cells. In all cases, the majority of nonepithelium-associated T cells present in the corium were HML-1 negative. In the eight cases with marked epidermotropism, the intraepidermal (IED) T cells were HML-1 positive in three cases, and HML-1 negative in the remaining five cases. The HML-1 positive IED T cells tended to be localized preferentially in the basal layers, whereas the HML-1 negative IED T cells were more diffusely distributed throughout all epidermal cell layers or formed intra-epidermal aggregates. These findings provide further evidence that mycosis fungoides is not a single entity, but represents a group of neoplasms originating from different T cell subsets that have in common their tropism to epidermis and/or dermis, and thus have a similar clinical presentation.  相似文献   
94.
Polypoid tumor of the esophagus   总被引:2,自引:0,他引:2  
Five cases of an uncommon esophageal tumor consisting of a mucosal squamous cell carcinoma that surrounds a polypoid mass of spindle cells were examined. The spindle cell component was composed of elongated cells with blunt nuclei, admixed with multinucleated giant cells. Reticulin fibers enveloped individual cells, and abundant collagen was present. Thirteen to 69 mitotic figures occurred per 10 high-power fields. Electron microscopy showed dilated cisternae of rough endoplasmic reticulum and peripheral intermediate filaments within the cytoplasm. Intermediate-type junctions (zonulae adherens) and subplasmalemmal linear densities connected some cells. No tonofibrillar bundles or desmosomes (maculae adherens) were present. Immunoperoxidase stains detected no keratin in the spindle cells. Alpha-1-antichymotrypsin and alpha-1-antitrypsin were in the spindle cells in five of five and three of five cases, respectively. The absence of desmosomes, tonofibrillar bundles, and keratin and the presence of alpha-1-antitrypsin and alpha-1-antichymotrypsin favor fibrohistiocytic differentiation of the spindle cell component.  相似文献   
95.
We report on three patients with Costello syndrome and isolated growth hormone (GH) deficiency treated with biosynthetic GH. To our knowledge, these are the only patients with Costello syndrome who have been successfully treated for GH deficiency. We review the pathophysiology of Costello syndrome and highlight the recent recommendations of tumor screening and cardiac surveillance in this population, of particular relevance to those receiving GH therapy.  相似文献   
96.
BACKGROUND: The knowledge available on electroconvulsive therapy (ECT) in adolescents is largely anecdotal, or based on findings from adults. The aim of the present study is to compare the use of ECT in adolescent and adult inpatients. METHODS: We retrospectively analyzed the files of all 36 adolescent (between the ages of 13 and 19) and 57 randomly selected adult inpatients (above the age of 20) treated with ECT in a university-affiliated mental heath center in Israel between 1991 and 1997. RESULTS: Sixty one percent of the adolescents improved by the end of treatment, and 53% were not hospitalized in the subsequent year. The respective percentages among adults were 83% and 49%. Whereas most adults were treated with ECT because of schizophrenic disorders, almost half of the adolescents received ECT for affective disorders. Significantly more adolescents were treated with ECT because of acute life-endangering conditions (catatonia or severe suicidal risk). No significant adverse effects were found in both groups. LIMITATIONS: Our study is based on a retrospective chart review. The adolescent and adult groups are different in psychiatric morbidity, diagnosis and outcome, have not been assessed in a blind manner, and we have not used standardized psychometric batteries for the evaluation of ECT-related memory disturbances. CONCLUSIONS: ECT may be an effective, well-tolerated and safe procedure in both adult and adolescent inpatients.  相似文献   
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99.
Lymph node sections from 10 cases of mixed nodular/diffuse and 10 cases of completely diffuse lymphocyte-predominant Hodgkin's disease (LPHD) were immunophenotyped. The results obtained were compared with those of nodular LPHD (nodular paragranuloma). In conventional stains, nodular/diffuse LPHD differed from diffuse LPHD in the presence of nodularity, which can be best demonstrated with silver impregnation. Immunohistologic analysis showed a correlation of the difference in nodularity with the presence or absence and pattern of follicular dendritic cell (FDC) meshwork, ie, a relatively sharply defined and large spherical meshwork was present in nodular areas of nodular/diffuse LPHD, whereas FDCs were either absent or present in a diffuse, ill-defined meshwork, usually of small size, in the diffuse zones of nodular/diffuse LPHD and in diffuse LPHD. The amount of FDC meshwork corresponded roughly to the number of reactive B cells and T cells, meaning that in diffuse areas significantly fewer B cells and more T cells were observed than in nodular areas. The immunohistologic analysis also showed that the antigen profile (positivity with the monoclonal B-cell marker L26 in the majority [14/20] of cases and negativity for CD15 in all but one of 20 cases) of the tumor cells in both nodular/diffuse LPHD and diffuse LPHD were comparable while it was different from the antigen profile (L26- and CD15+) in most cases of nodular sclerosis and mixed cellularity types of HD. This suggests that the considered subtypes of LPHD differ mainly in FDC pattern, but not in origin and nature of the tumor cells. This further justifies assignment of the above-mentioned LPHD subtypes to the category paragranuloma (LPHD).  相似文献   
100.
An immunomorphometric study was performed on bone marrow biopsies from 40 patients with primary osteomyelofibrosis--OMF, (agnogenic myeloid metaplasia) by employment of a monoclonal antibody against glycoprotein IIIa (Y2/51) to determine the number of pro-megakaryoblasts. Specimens from 15 individuals without any hematological disorder served as controls. With reference to the pertinent literature on megakaryocyte precursors and following a pilot study on corresponding smears, in tissue sections pro-megakaryoblasts were characterized by a size of 42.1 +/- 2.6 microns 2 (diameter 7.5 +/- 0.3 microns). In comparison with controls, in OMF no relevant increase in the number of pro-megakaryoblasts per square and cubic millimeter bone marrow was evaluable. The relative frequency of these precursors was significantly reduced due to an increase in the total amount of conspicuously large and abnormal megakaryocytes. Statistical analysis failed to reveal any correlations between counts for pro-megakaryoblasts or the total number of Y2/51--positive megakaryocytic elements with the density of argyrophilic fibers (determined by morphometry) or the platelet values. Our findings imply that in OMF the marked increase in circulating progenitor cells of the megakaryocyte lineage may be generated by extramedullary, probably splenic hematopoiesis. Moreover, the evolution of medullary fibrosis is thought to be associated with the striking predominance of large atypical, possibly overaged and hyperpolyploid megakaryocytes and not with an increase in precursor cells.  相似文献   
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