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101.
Lysenko ON Strizhova NV Kholodova ZhL 《Bulletin of experimental biology and medicine》2003,135(1):77-80
No appreciable disorders of cellular immunity were detected in patients with glandular cystic endometrial hyperplasia. Atypical endometrial hyperplasia was associated with quantitative changes in T lymphocytes and their subpopulations, decreased level of lymphocytes carrying activation antigens, and increased count of natural killers. These changes can be characterized as immunocompensation. 相似文献
102.
Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon lesion usually found in premenopausal women. Histologically, it is characterized by complex, anatomosing, empty slit-like spaces in a dense collagenous stroma. These pseudoangiomatous spaces are lined by monomorphic spindle cells of myofibroblastic differentiation. Cytological features of PASH are rarely discussed and reported, and may pose diagnostic challenge to surgical pathologists. Two cases of PASH are reported with emphasis on the FNAC features and cytologic differentiation from other benign fibroepithelial lesions. 相似文献
103.
A "floral" variant of nodal marginal zone lymphoma 总被引:1,自引:0,他引:1
Karube K Ohshima K Tsuchiya T Yamaguchi T Kawano R Suzumiya J Harada M Kikuchi M 《Human pathology》2005,36(2):202-206
We describe 6 cases of a specific variant of nodal marginal zone lymphoma with "floral" lymph follicles in patients ranging in age from 18 to 66 years. All 6 patients had lymphadenopathy, either local (n = 5) or systemic (n = 1), and good performance status (0), and none had fever, weight loss, or night sweating. They all underwent excisional biopsy. Histologically, all lesions had a distinctive morphology, with proliferation of medium-sized atypical lymphoid cells in the marginal zone, hyperplastic lymph follicles with enlarged germinal centers, and a thickened mantle zone. In places, folliculolysis was observed. On immunohistochemical staining, the atypical lymphoid cells showed a B-cell phenotype (CD20 +), IgM positivity in 2 of 5 cases, and negativity for CD5, CD10, CD23, CD43, bcl-6, and IgD. Polymerase chain reaction examination for immunoglobulin heavy chain in 5 cases showed monoclonality in all. Five patients did not receive adjuvant chemotherapy and had no recurrences. The patient with systemic lymphadenopathy received chemotherapy and had a complete response without relapse. This variant should be differentiated from the usual nodal marginal zone lymphoma because of its specific clinical and pathological features. 相似文献
104.
The histopathology of papillary thyroid hyperplasia and papillary thyroid carcinoma is similar enough to cause a diagnostic
dilemma in a few cases. Both lesions may have papillary fronds with fibrovascular cores, nuclear crowding, and nuclear anisocytosis.
Formalin-fixed paraffin-embedded tissues from 30 randomly selected patients with papillary thyroid hyperplasia and an equal
number from patients with papillary thyroid carcinoma were analyzed for expression of cytokeratin 19 (CK19), galectin-3, and
HBME-1. Cases of papillary thyroid carcinoma had moderate to strong CK19, galectin-3, and HBME-1 reactivity although both
CK19 and galectin-3 showed positive staining in a significant number of nonneoplastic thyroid cases. HBME-1 was uncommon in
the nonneoplastic cases. These results indicate that HBME-1 may be useful in helping to distinguish papillary thyroid carcinoma
from hyperplasia in diagnostically difficult cases. 相似文献
105.
Follicular hyperplasia presenting with a marginal zone pattern in a reactive lymph node lesion 总被引:1,自引:0,他引:1
Kojima M Nakamura S Motoori T Shimizu K Ohno Y Itoh H Masawa N 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2002,110(4):325-331
Histologically, the marginal zone pattern of the lymph node is characterized by lymphoid follicles with three distinct layers. The inner layer is composed of follicular center zones, the middle layer of darkly stained mantle zones, and the outer layer of marginal zones. However, the marginal zone pattern is rarely seen in reactive lymph nodes except for mesenteric lymph nodes. We describe the clinicopathologic, immunohistochemical and genotypic findings of six cases of reactive follicular hyperplasia exhibiting the marginal zone pattern. The patients comprised three males and three females (age range 24 to 63 years; medium 56 years). Follow-up data were obtained from five patients. None of them developed malignant lymphomas during the follow-up period of from 5 to 204 months (median 68 months). Histologically, the lesion was characterized by numerous lymphoid follicles and partial distortion of lymph node structure. Varying degrees of progressive transformation of the germinal center (PTGC) were noted in the four cases. The marginal zone pattern was observed in some or most of the lymphoid follicles including PTGC. The marginal zone B cells were small to medium-sized lymphocytes with round or slightly indented nuclei and a broad rim of pale cytoplasm. Some of them had a monocytoid appearance. They were CD20+, CD79a+, sIgM+/-, sIgD-, CD5-, CD10-, CD21-, CD23-, CD43-, CD45RO-, Bcl-6-, cyclin D1-, EMA- and p53-. A portion of them were Bcl-2 positive. Occasional large lymphoid cells with round or indented nuclei and moderate amounts of cytoplasm were observed in the marginal zone in four cases. These large lymphoid cells were usually CD20 positive, but Bcl-6 negative. A small number of them contained polytypic intracytoplasmic immunoglobulins. The polytypic nature of B lymphocytes was demonstrated by immunohistochemistry and polymerase chain reaction. Recognition of unusual marginal zone hyperplasia in reactive lymph node lesions is important to avoid confusion with nodal involvement in various low-grade B cell lymphomas presenting a marginal zone distribution pattern. 相似文献
106.
An unusual case study of a desmoplastic small round cell tumor presenting as a 3.5-cm, firm, supraclavicular neck mass and diagnosed by fine-needle aspirate biopsy in a 16-yr-old male is reported. Clinical, cytologic, and immunocytochemical findings are described. Histologic, immunohistochemical, and genetic features are discussed. Desmoplastic small round cell tumor should be considered in the differential diagnosis of small round cell tumors of any site; the importance of ancillary studies in arriving at the correct diagnosis is emphasized. 相似文献
107.
Normal hyperplastic and malignant endometrial specimens were labelled in vitro with bromodeoxyuridine (BrdU). S-phase cells were stained after DNA denaturation, using a monoclonal antibody to BrdU and an indirect immunoperoxidase method. Various conditions for BrdU uptake, DNA denaturation, and staining were tested. BrdU labelling was compared with autoradiography using tritiated thymidine, with good correlation. Glandular labelling indices of proliferative endometrium were significantly higher than both secretory and hyperplastic endometrium but were similar to carcinoma. Stromal labelling showed the same trend but the differences were not statistically significant. 相似文献
108.
Fluid and solid mechanical implications of vascular stenting 总被引:10,自引:0,他引:10
Vascular stents have emerged as an effective treatment for occlusive vascular disease. Despite their success and widespread use, outcomes for patients receiving stents are still hampered by thrombosis and restensosis. As arteries attempt to adapt to the mechanical changes created by stents, they may in fact create a new flow-limiting situation similar to that which they were intended to correct. In vitro fluid mechanics and solid mechanics studies of stented vessels have revealed important information about how stents alter the mechanical environment in the arteries into which they are placed. Adverse nonlaminar flow patterns have been demonstrated as well as remarkably high stress concentrations in the vessel wall. In vivo studies of stented vessels have also shown a strong relationship between stent design and their dynamic performance within arteries. Alterations in pressure and flow pulses distal to the stent have been observed, as well as regional changes in vascular compliance. Considering the influence of flow and stress on the vascular response and the suboptimal clinical outcomes associated with stenting, knowledge gained from stent/artery mechanics studies should play an increasingly important role in improving the long-term patency of these devices. © 2002 Biomedical Engineering Society.
PAC2002: 8719Rr, 8780-y, 8719Uv 相似文献
109.
Hampton NR Rees MC Lowe DG Rauramo I Barlow D Guillebaud J 《Human reproduction (Oxford, England)》2005,20(9):2653-2660
BACKGROUND: This study was designed to assess the long-term efficacy (5 years) of the levonorgestrel-releasing intrauterine system (LNG-IUS) in protecting the endometrium from hyperplasia during estrogen replacement therapy in perimenopausal women. METHODS: Prospective, open, outpatient clinical trial in London and Oxford. Eighty-two women received oral conjugated equine estrogen 1.25 mg daily and LNG-IUS releasing 20 mug levonorgestrel per 24 h. Endometrial biopsy and histological assessment were performed annually. Endometrial thickness was measured by vaginal ultrasonography. RESULTS: Non-proliferative endometrium was present at the end of cycles 12, 24, 36, 48 and 60 in 98.6, 98.6, 95.5, 96.8 and 95.2% of the participants respectively. No endometrial hyperplasias were confirmed throughout a period of 60 cycles. The proportion of amenorrhoeic women increased from 54.4% at 12 cycles to 92.7% at the end of the study. The continuation rate per 100 women at 60 cycles was 79.84 (95% CI 71.0-88.6). CONCLUSIONS: The LNG-IUS with estrogen supplementation in perimenopausal women suppresses endometrial proliferation resulting in amenorrhoea and relieves vasomotor symptoms. The treatment regimen is well tolerated and provides an alternative strategy for perimenopausal women with the likelihood of increasing compliance. 相似文献
110.
A case of granular cell tumor (GCT) arising in the neurohypophysis of a 63-year-old woman is reported. The tumor consisted of ovoid, polygonal or spindle-shaped cells in a sheet-like or fascicular arrangement. Its abundant cytoplasm contained granules positive for diastase-resistant periodic acid-Schiff reaction. Ultrastructurally, the tumor cells contained numerous polymorphic lysosomes of various densities. Immunohistochemically, the tumor cells were positive for S-100 protein, glial fibrillary acidic protein and Leu7, suggesting that the tumor originated from pituicytes that were thought to be modified astrocytes in the neurohypophysis and its stalk. The granular cells showed nuclear atypia, pleomorphism and increased mitotic activity. Therefore, the present tumor was considered as a histologically atypical GCT. Interestingly, proliferating cell nuclear antigen, Ki-67 and p53 were stained in a few tumor cells of this case. These findings indicate that the present tumor had a malignant potential. 相似文献