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41.
Most models suggest that the cell of origin of papillary carcinoma is the mature thyroid follicular epithelial cell. In a recent study, p63 was detected in papillary carcinoma, Hashimoto's thyroiditis, and in squamoid aggregates and solid cell nests (SCNs), embryonic remnants found sporadically in the fully developed thyroid. In the present study, the relationship between solid cell nests and papillary carcinoma was investigated further. Four-micrometer sections from 88 routinely fixed and processed archival thyroidectomy specimens were pretreated with citric acid pH 6.0 for antigen retrieval, then incubated overnight with anti-p63 monoclonal antibody 4A4. Slides were stained with a streptavidin-biotin kit and diaminobenzidine as chromogen and were counterstained with hematoxylin. Squamoid aggregates or SCNs were noted in 21 specimens. Several morphologic variants of SCNs were found, all of which displayed p63 positivity. These included undifferentiated SCNs and those displaying commitment toward squamoid and ciliated glandular differentiation. Small, morphologically inconspicuous aggregates of p63-positive cells were commonly found in Hashimoto's thyroiditis. Commitment of p63-positive undifferentiated cells toward thyroid follicular epithelial differentiation was occasionally noted. One SCN variant, also associated with Hashimoto's thyroiditis, was a floretlike arrangement of p63-positive cells with fusiform nuclei. p63 staining was strong and uniform in some SCNs, but in other SCNs it was compartmentalized and homologous to stem cell-staining patterns in normal squamous or bronchial epithelia. Stem cell-like staining, associated with compartmentalized p63 staining or p63-positive undifferentiated cells, was noted in 7 of 27 papillary carcinomas. p63 immunostaining is a highly sensitive means of detecting SCNs. p63 expression patterns in SCNs and a subset of papillary carcinomas are closely homologous to stem cell-associated p63 staining patterns that have been described elsewhere in squamous and bronchial epithelia. We propose a stem-cell-associated model of papillary carcinoma oncogenesis that suggests that (1) p63-positive embryonal remnants rather than mature follicular cells are the cells of origin of a subset of papillary carcinomas; (2) these p63-positive cells are pluripotent and may stay undifferentiated or undergo benign squamoid or glandular maturation, may undergo thyroid follicular epithelial differentiation, may undergo oncogenic change leading to papillary carcinoma, or may trigger an immune reaction, resulting in lymphoid infiltration and Hashimoto's thyroiditis; and (3) Hashimoto's thyroiditis and papillary carcinoma may therefore be linked etiologically, because both disorders may be initiated by the same population of pluripotent p63-positive embryonal stem cell remnants. 相似文献
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E R Unger F W Chandler M L Chenggis C Y Ou D T Warfield P M Feorino 《Modern pathology》1989,2(3):200-204
A colorimetric method of in situ hybridization has been developed for the rapid detection of human immunodeficiency virus (HIV) in formalin-fixed paraffin-embedded material. Following optimization of digestion conditions, biotin-labeled DNA probes are detected with an alkaline phosphatase conjugate. The method is verified using fixed paraffin-embedded cell blocks of HIV-infected and uninfected lymphocyte cell cultures. Hybridization specifically detects both viral RNA and proviral DNA. Formalin fixation for intervals up to 21 d did not significantly hamper the signal under the appropriate digestion conditions; however, Trump's fixation for even 12 h greatly reduced the intensity of the hybridization. This technique for in situ hybridization is amenable to automation, provides results within 6 h, and results in good morphologic preservation. A key feature of the technique is the use of human placental DNA as an endogenous positive control to optimize the empirically determined conditions for protein digestion. 相似文献
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Wang BY Strauchen JA Rabinowitz D Tillem SM Unger PD 《Archives of pathology & laboratory medicine》2001,125(9):1239-1241
We report the case of a 77-year-old white woman who presented with a left breast mass, lethargy, and weight loss. Pelvic computed tomographic scan revealed a 9.5-cm mass in the right kidney. Surgical pathology demonstrated a diffuse large B-cell lymphoma of the subcutaneous tissue of the breast and renal cell carcinoma with concurrent extensive intravascular lymphomatosis. Systemic dissemination of malignant lymphoma to a concurrent visceral primary neoplasm is rare. To the best of our knowledge, this is the first case illustrating a renal cell carcinoma collision with intravascular lymphomatosis. 相似文献
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Summary The presence, chromatographic properties and localization of neuropeptide Y was demonstrated in postmortem human brain areas of neurologically and neuropsychiatrically normative controls using immunocytochemistry and high performance liquid chromatography combined with radioimmunoassay. NPY-immunoreactivity was found in many regions of the prosencephalon. Numerous perikarya and fibers were present in the neocortex, basal ganglia and limbic-hypothalamic areas. A moderate number of neurons and fibers was observed in the basal forebrain, including the septal complex. A comparative immunohistochemical investigation in perfusion-fixed brains of the old-world ape Saguinus oedipus revealed an almost identical distribution of NPY-immunoreactivity with only minor differences. Colocalization experiments on 1–2 m thin consecutive paraffin sections revealed a large number of NPY neurons throughout the human neostriatum and amygdaloid complex that were also positive for somatostatin. Our findings indicate that detection of neuropeptides in fresh or fixed post-mortem human tissue by different immunochemical methods may actually reflect the in vivo conditions. In addition, the wide distribution of NPY throughout the human brain and its colocalization with other neurotransmitters suggests a physiological role as neuroactive substance, i.e. neuromodulator in the primate central nervous system. 相似文献
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0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、… 相似文献
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A retrospective study was carried out at our institution to compare patients who underwent percutaneous endoscopic gastrostomy (PEG) to those who underwent laparoscopic gastrostomy (LG). There were 17 patients who had a PEG with a mean age of 81 years (43–97 years). The procedure time, including complete esophago-gastroduodenoscopy, averaged 28 min. There were four deaths (23%) in a 30-day period, but none of these were directly related to the procedure. The LG group consisted of 14 patients with a mean age of 66 years (20–94 years). Mean duration of the procedure was 18 minutes. Thirty-day mortality rate was 35% (five patients) with one death (7%) directly related to the tube. Indications for gastrostomy were similar in both groups, being predominantly inability to eat and/or recurrent aspiration. However, LG was done because of 4 technical failures, 5 patients with tumors of the head and neck, 2 patients with esophageal obstruction and radiation stenosis precluding safe PEG, and 1 patient with hiatal hernia; 2 LGs were performed at the surgeon’s preference. Outcomes for LG and PEG were comparable. LG is a suitable, safe alternative to PEG in selected patients who cannot undergo gastroscopy and should be considered the procedure of choice in patients with head and neck tumors or intrathoracic pathology that prevents PEG. 相似文献