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91.
Fine-needle aspiration cytology of phyllodes tumors 总被引:3,自引:0,他引:3
Breast lesions with a significant spindle cell or mesenchymal component are not commonly encountered in fine-needle aspiration (FNA) cytologic material and include a heterologous variety of benign and malignant conditions, with phyllodes tumors (PTs) being the foremost differential diagnostic consideration. This study comprises 28 tumors diagnosed histologically as PT in which FNAC material was available for review. Histological sections and cytological smears from these cases were retrieved and subjected to detailed morphological review. Cytological parameters assessed included ratio of stroma to epithelium, pattern characteristics and cytological characteristics of the stromal, and epithelial components and the background cells. Large and hypercellular stroma fragments, dissociated spindle and plump stromal cells, often accompanied by large, folded sheets of epithelium were cytological features that characterized PT. Smears from malignant PT showed predominantly or solely mesenchymal components. FNAC was a highly reliable procedure for the diagnosis of PT, giving an accuracy rate of 92.8%. 相似文献
92.
I. A. Vinogradova A. V. Bukalev M. A. Zabezhinski A. V. Semenchenko V. Kh. Khavinson V. N. Anisimov 《Bulletin of experimental biology and medicine》2008,145(4):472-477
Exposure of male rats to permanent or natural illumination of North-Western Russia accelerated their death in comparison with
animals exposed to standard (12 h) light. Permanent illumination promoted the development of spontaneous tumors in comparison
with the standard photoregimen. Injection of epithalone (synthetic Ala-Glu-Asp-Gly peptide; subcutaneously 0.1 μg/rat 5 times
a week from the age of 4 months until natural death) virtually did not change the mean lifespan of male rats, but was associated
with a significant (p<0.05) normalization of population aging rate and hence, time of mortality rate doubling in groups exposed to natural or constant
illumination. Epithalone injected to rats exposed to any photoregimen significantly inhibited the development of spontaneous
tumors, primarily testicular leydigomas and leukemias.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 4, pp. 455–460, April, 2008 相似文献
93.
94.
95.
The role of intraoperative frozen section in certain organ systems such as the thyroid continues to be problematic. In many
cases, diagnoses are deferred or nonhelpful—“follicular lesion.” In the modern era, the widespread use of preoperative aspiration
biopsy has allowed for more careful selection of patients who undergo thyroid surgery. In many cases, the fine-needle-aspiration
(FNA) biopsy diagnosis can be definitive or can guide the specific surgical procedure. The literature supports our approach,
which is summarized as follows: Intraoperative consultation is not needed on the intrathyroidal nodule if a preoperative FNA
was definitive for papillary carcinoma. Frozen section is of no value in the intraoperative diagnosis of lesions diagnosed
on FNA as “follicular neoplasm” or “Hürthle cell neoplasm” because the characterization of these lesions requires detailed
analysis of the tumor capsule for the demonstration of capsular and/or vascular invasion—an analysis that is not practical
in the intraoperative setting. Finally, intraoperative consultation including frozen section and intraoperative cytologic
examination is most useful in those cases that are diagnosed as suspicious for papillary carcinoma by FNA, because the assessment
of nuclear features needed for the definitive diagnosis is possible with intraoperative techniques in a significant number
of cases. 相似文献
96.
97.
邓天权 《生物医学工程学杂志》1991,8(4):299-304
本文提出并研究了一种新型的电磁热疗系统-H面号角环形相控阵系统。推导出了适应性广的理论公式。以肺部CT图为模型,用矩量法计算得到了胸腔横断面内电场分布及吸收功率分布的计算机数值结果。结果表明,在200MHz的电磁波辐射下,适当调节阵列各单元的相位,振幅和位置,肺部肿瘤可得到优化的选择性加热,从而达到最佳的热疗效果。 相似文献
98.
Mixed epithelial and stromal tumors of the kidney. A report of 22 cases 总被引:16,自引:0,他引:16
Michal M Hes O Bisceglia M Simpson RH Spagnolo DV Parma A Boudova L Hora M Zachoval R Suster S 《Virchows Archiv : an international journal of pathology》2004,445(4):359-367
Mixed epithelial and stromal tumor of the kidney (MESTK) is a recently described subset of renal neoplasm that tends to occur in middle-aged and older women and is characterized by a distinctive histological appearance. To further characterize this lesion, we report the clinicopathological and immunohistochemical features of 22 additional cases from our institutional files. Grossly, the tumors ranged in size from 1 cm to 14 cm (mean 6.7 cm), were well circumscribed but unencapsulated, and showed a cystic cut surface. The tumors were composed of a spindle cell proliferation that resembled ovarian stroma, as well as an epithelial component lining the cystic structures, which usually consisted of flat to hobnailed cells typical of collecting-duct epithelium. Areas displaying features of Müllerian differentiation were also documented in 6 cases, including epithelium of endometrioid, tubal, clear cell and squamous cell type as well as one case showing an architecture that closely resembled Müllerian adenofibroma and adenosarcoma. Follow-up in 14 patients (average 4.4 years) showed no evidence of recurrence or metastasis. We believe these tumors represent the renal counterpart of similar mixed epithelial and stromal neoplasms occurring in the biliary tract and pancreas, which is also characterized by cystic structures lined by epithelium, admixed with ovarian-type stroma. The differential diagnosis for these tumors includes cystic nephroma and cystic partially differentiated nephroblastoma, which we believe to represent clinically and morphologically distinct entities from MESTK. In particular, the distinction from cystic nephroma in adult male patients is emphasized, and two cases of this entity are included in the study for comparison. 相似文献
99.
Ella Israeli Batya Raz Hedwiga Kerner David Barzilai 《Breast cancer research and treatment》1985,6(3):241-248
The levels of cyclic adenosine 3:5-monophosphate (cAMP) and cyclic guanosine 3:5-monophosphate (cGMP) were studied in dimethylbenz(a)anthracene (DMBA)-induced mammary tumors of Sprague-Dawley rats and in human breast cancer. In the rat carcinomas, these levels were significantly lower than in non-malignant tissues when calculated on the basis of DNA content, but higher (cAMP) or equal (cGMP) when calculated on the basis of weight. In human breast cancer the cyclic nucleotide levels were higher than in non-malignant tissues according to both methods of calculation. No correlation was found in human carcinomas between the cyclic nucleotide levels and mitotic index, nuclear grade, tumor size, or lymph node involvement. The rat tumors were subclassified according to state of differentiation, mitotic index, and state of development. Not all the sub-groups had cAMP levels different from normal values. Differences in cAMP levels between the sub-groups could not be correlated with tumor growth rates and/or mitotic index. Thus, cyclic nucleotides may not be useful in prognosis of breast cancer. 相似文献
100.
R P Müller H W Addicks E M Meier 《International journal of radiation oncology, biology, physics》1985,11(9):1613-1619
In order to analyze the possible meaning of cellular DNA content and cell cycle phases for the radiosensitivity and the prognosis of human malignant tumors, flow cytometric measurements have been performed in biopsies of 131 patients with histologically proven squamous cell carcinomas of the maxillo-facial region. In two-thirds of the patients (88/131; 67%), aneuploid tumor cell lines have been found, only 33% (43/131) had a diploid DNA distribution pattern. The average DNA index (DI) of the aneuploid carcinomas was 3.4 +/- 0.6 (normal nonmalignant tissue DI = 2.0). The frequency of S-phase cells, which represents the "proliferative activity", was between 4.8 and 63.2%, regardless of the ploidy stages. The aneuploid carcinomas had about twice as many S-phase cells (mean 23.7 +/- 11.8%) than diploid tumors (mean 12.7 +/- 4.8%). Mean survival for patients with diploid carcinoma and aneuploid carcinoma was 12 and 9.5 months, respectively. Concerning the relationship of S-phase frequency and survival times in our material there was a high negative statistical correlation (Spearman-Rank test) in patients with diploid carcinomas. A high S-phase fraction resulted in short survival times. No correlation was found in the aneuploid carcinomas: patients with tumors in high S-phase values in their biopsies showed no difference in prognosis in comparison to tumors with lower S-phase fractions. 相似文献