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971.
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973.
In an attempt to find whether or not p53 immunoreactivity in the thyroid gland is restricted to undifferentiated carcinomas and to evaluate the putative prognostic usefulness of its detection, we investigated p53 immunoreactivity in a series of 14 benign thyroid lesions and 65 thyroid carcinomas (12 papillary; six minimally invasive follicular; four widely invasive follicular; 31 poorly differentiated and 12 undifferentiated tumours). Unequivocal nuclear immunostaining for p53 was observed in two widely invasive follicular carcinoma (20.0%), five poorly differentiated carcinomas (16.1%) and in 10 undifferentiated carcinomas (83.3%). The percentage of immunoreactive cells was much smaller in the former groups than in undifferentiated carcinomas. Despite a trend to a more aggressive behaviour of the p53 immunoreactive cases no significant differences in the outcome of patients with positive and negative tumours was found when the comparison was made within each category of carcinomas. We conclude that p53 immunoreactivity can be detected both in undifferentiated carcinomas and in some differentiated and poorly differentiated thyroid carcinomas. Larger series of cases are necessary to evaluate the prognostic usefulness of this finding. 相似文献
974.
Summary: IgA nephropathy is a clinically and histologically defined syndrome of unknown aetiology, which may have various causes in different parts of the world. Immunologically it is characterized by deposition of IgA1, probably polymeric IgA, in the mesangium and is frequently associated with IgG, C3 and components of the alternative pathway of the complement cascade. the disease can go into complete remission in children, but in adults it usually has a progressive course, characterized by the appearance of proteinuria and hypertension and loss of glomerular filtration rate (GFR). Histologically the development of glomerulosclerosis and tubulo-interstitial changes correlate with a clinical progressive course. the mucosal immune system is characterized by high plasma IgAl antibody responses after parenteral immunization with viral or bacterial vaccines. However, following nasal challenge with a bacterial neoantigen, IgA nephropathy patients appear to have a defective mucosal immune response in their nasal washes, in their bone marrow and in their plasma IgA1 antibody levels. 相似文献
975.
976.
S Cho† ES Park† DH Lee† K Li† JH Chung‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(9):1108-1113
BACKGROUND: Despite the high prevalence of striae distensae, clinical studies are few in number, and their pathophysiology still obscure. OBJECTIVES: To determine the prevalence and clinical characteristics of striae distensae that occur in Korean adolescents, and to correlate their clinical features with family history, other dermatological conditions, and body measurements. METHODS: One hundred and fifty-seven healthy Korean students, aged 15 to 17, were studied. A questionnaire and physical examination were employed to assess the subjects' past and family history, and the distribution, clinical features and severity of striae distensae. RESULTS: Striae distensae were present in 131 subjects (83.4%). Ninety-four (88.2%) of 109 male and 37 (77.1%) of 48 female subjects were affected. The striae were white in colour in 69.5% and asymptomatic in most of the subjects. They developed at an average age of 13.8 years. Family history was present in 18 subjects (11.5%). Seborrhoea of the face was positively correlated (P < 0.035) with striae distensae, and atopic dermatitis negatively correlated (P < 0.001). In both sexes, the buttock was the most prevalent area of striae development, followed by the lower back and knee in boys and by the thigh and calf in girls. Striae were significantly more common on the thigh of girls and on the knee of boys. CONCLUSIONS: Our results indicate that striae distensae are a common skin condition that occurs early in puberty regardless of gender, and that they have a different anatomical distribution and relationship with body measurements in each gender. 相似文献
977.
978.
Dilated fallopian tubes: MR imaging characteristics 总被引:5,自引:1,他引:4
Outwater EK; Siegelman ES; Chiowanich P; Kilger AM; Dunton CJ; Talerman A 《Radiology》1998,208(2):463
979.
Syed H Kamil Marcia Woda Lawrence J Bonassar Yuri W Novitsky Charles A Vacanti Roland D Eavey Martin P Vacanti 《Otolaryngology--head and neck surgery》2003,129(4):390-396
BACKGROUND: Cytokinetic abnormalities in DNA content, such as aneuploidy, haploidy, and tetraploidy, have been found to occur in human cartilaginous tumors. The high number of chondrocytes needed for tissue-engineered cartilaginous implants requires the cells to be passaged repeatedly. The theoretical risk of changes in the normal diploid state of these cells during their growth in vitro and after generation of tissue-engineered cartilage in vivo is not known.Materials and methods Auricular chondrocytes were obtained from 6 patients and cultured in vitro. Chondrocyte number was increased by repeated passaging. The passaged cells were implanted in nude mice for 8 weeks to generate tissue-engineered cartilage. Fresh control chondrocytes along with the passaged cells and cells obtained from the tissue-engineered constructs were collected and compared for DNA content by flow cytometry. RESULTS: Flow cytometry demonstrated 100% diploidy with no evidence of aneuploidy, haploidy, or tetraploidy in all groups of cells. Histology of the tissue-engineered cartilage also showed no evidence of cellular atypia. CONCLUSION: The number of human auricular chondrocytes can be increased by repeated passaging and passaged chondrocytes can be safely used for implantation to generate tissue-engineered constructs without a change in the normal diploid state of the cells. Histology of the cartilage generated showed normal features without atypia. 相似文献
980.
EULÁLIA PEREIRA M.D. NUNO FERREIRA M.D. DANIEL CAEIRO M.D. JOÃO PRIMO M.D. LUÍS ADÃO M.D. MARCO OLIVEIRA M.D. HELENA GONÇALVES M.D. JOSÉ RIBEIRO C.C.V.T. ELISABETH SANTOS C.C.V.T. DANIEL LEITE R.T. NUNO BETTENCOURT M.D. PEDRO BRAGA M.D. LINO SIMÕES M.D. LUÍS VOUGA M.D. VASCO GAMA M.D. 《Pacing and clinical electrophysiology : PACE》2013,36(5):559-569