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991.
Pauwels P Dal Cin P Roumen R van den Berghe H Sciot R 《Virchows Archiv : an international journal of pathology》1999,434(2):167-171
A case of an entirely intramuscular mixed tumour occurred in an 82-year-old man, who presented with a large mass in the region
of the right triceps muscle. A lobulated tumour was seen, with plump, round epithelioid cells embedded in a chondromyxoid
stroma. Immunohistochemical examination showed strong S100 protein and pancytokeratin positivity in most of the tumour cells.
Cytogenetic analysis revealed complex clonal chromosomal changes: 47, XY, +i (2) (q10), –15, der (17)t(15;17) (q11; p12),
+r. Differential diagnosis against extraskeletal myxoid chondrosarcoma (EMC) may be problematic, particularly in an incisional
biopsy. Chromosomal analysis can be very helpful in solving this problem, since EMC shows a specific reciprocal chromosome
translocation characterised as t (9;22) (q22–31) (q11–12).
Received: 8 July 1998 / Accepted: 22 September 1998 相似文献
992.
nm23-H1、p53、PCNA表达与大肠癌浸润转移的关系 总被引:14,自引:1,他引:14
目的:研究大肠癌中nm23-H1、p53、PCNA的表达与浸润转移的关系。方法:应用LSAB免疫组织化学方法检测74例大肠癌中nm23-H1、p53、PCNA和Ⅳ型原的表达。结果:大肠癌中nm23-H1、p53和PCNA的阳性率分别为71.6%、52.7%和81.1%。大肠癌中nm23-H1低表达与淋巴结转移有关(P<0.025),nm23-H1的表达在Ⅳ型胶原表达不同的肠癌中无明显差异(P>0.05);p53和PCNA过表达与浸润程度和淋巴结转移有关(P<0.05),p53和PCNA的表达在Ⅳ型胶原表达不同的肠癌中有非常显著的差异(P<0.005);大肠癌中p53过表达与nm23-H1低表达有关(P<0.01)。结论:实验结果揭示p53基因突变对于nm23-H1基因的失活有一定影响,其作用机制有待深入研究。nm23-H1低表达可能仅在大肠癌转移过程中发挥作用,p53过表达可在大肠癌浸润转移过程及细胞增殖中起重要作用。 相似文献
993.
Replicative MCM7 protein as a proliferation marker in endometrial carcinoma: a tissue microarray and clinicopathological analysis 总被引:3,自引:0,他引:3
Li SS Xue WC Khoo US Ngan HY Chan KY Tam IY Chiu PM Ip PP Tam KF Cheung AN 《Histopathology》2005,46(3):307-313
AIMS: To assess, in tissue microarray (TMA), the proliferative activity of endometrial carcinoma using one of the minichromosome maintenance (MCM) proteins (MCM7), and to explore its potential value for prognosis. MCM proteins are essential for eukaryotic DNA replication and have recently been used to define the proliferative compartments in human tissues. METHODS AND RESULTS: Immunohistochemistry for MCM7 and Ki67 was performed on TMAs constructed from 212 cases of endometrial carcinoma. MCM7 and Ki67 expression was quantified according to the extent of nuclear staining. An analysis was carried out of the association between MCM7 expression and that of Ki67 and the clinicopathological characteristics of endometrial carcinoma. MCM7 and Ki67 immunoreactivity was clearly evident in the nuclei of tumour cells. MCM7 and Ki67 labelling indices in endometrial carcinomas correlated with each other (P < 0.001). A significant correlation existed between the MCM7 labelling index and histological grade (P = 0.008) and patients' age at diagnosis (P < 0.001). Well-differentiated carcinomas and younger patients had a lower MCM7 index. Poor survival was observed in patients with endometrial carcinoma with a high MCM7 index (P = 0.03) and MCM7 was found to be an independent prognostic factor by multivariate analysis (P = 0.04). The Ki67 labelling index correlated with histological grade (P = 0.01) but had no significant prognostic impact (P = 0.50). CONCLUSIONS: In this TMA study on endometrial carcinoma, MCM7 was found to be a more reliable and useful marker than Ki67 in assessing tumour proliferation and in the prognosis of patients. 相似文献
994.
Nonulcerative penile mass lesions are rare. Pathological diagnosis of these lesions would traditionally be a biopsy. We report two such primary penile lesions which were diagnosed by fine-needle aspiration cytology (FNAC). Both lesions were present in the shaft and were diagnosed as squamous cell carcinoma (SCC). The first patient had a recurrence on the penile stump of partial amputation without any ulceration. The second had a primary urethral carcinoma on the terminal penile shaft infiltrating the corpora cavernosa dorsally. Open biopsies were avoided in both cases. FNAC was associated with very little and tolerable discomfort. There were no complications. The aspirate yield was sufficient for cytological diagnosis. FNAC of nonulcerated penile lesions is safe, well tolerated, and capable of providing a cytological diagnosis. Hence, it is a very useful outpatient procedure and could be the procedure of choice for diagnosis. 相似文献
995.
胰腺黏液性囊性肿瘤临床病理分析 总被引:2,自引:0,他引:2
目的;探讨胰腺黏液性囊性肿瘤(MCN)的临床病理学特点。方法:6例MCN均行B超或CT检查。除1例外,均作了手术切除治疗。对6例(MCN)作常规HE及免疫组织化学染色观察。结果:6例MCN中,女性4例,男性2例,平均年龄47岁,均位于胰腺体尾部。黏液性囊腺瘤(MCA)3例,囊壁内衬高柱状黏液上皮,上皮周围可见卵巢样间质组织;黏液性囊腺癌(MCC)3例,黏液上皮 有不典型增生,均有囊壁或胰腺组织的浸润,1例上皮周围可见卵巢样间质。CEA和CK 7在上皮中均阳性,c-erbB-2均阴性,间质SMA均阳性。结论:胰腺MCN是好发于中年女性的少见肿瘤,绝大多数发生于胰腺体尾部。MCA内衬高柱状上皮,上皮外来卵巢样间质包绕;MCC上皮细胞有不典型增生, 浸润性生长。MCN手术切除率高。 相似文献
996.
腓肠神经营养血管皮瓣修复足背皮肤软组织缺损 总被引:1,自引:1,他引:1
目的探讨腓肠神经营养血管皮瓣修复足背皮肤软组织缺损的疗效及其适应证。方法21例腓肠神经营养血管皮瓣转位修复足背皮肤软组织缺损,其中5例皮瓣远端达到跖趾关节,皮瓣面积(6cm×4cm)~(15cm×13cm)。结果21例皮瓣中,16例皮瓣远端在跖趾关节以近者完全成活;5例皮瓣远端达到或者超过跖趾关节者有3例皮瓣远端部分坏死,2例皮瓣远端小隐静脉与足背静脉吻合者完全成活。结论腓肠神经营养血管皮瓣是一种修复足背皮肤软组织缺损的较理想的手术方法,其修复创面的最远端可达到跖趾关节。 相似文献
997.
Elevated expression in situ of selectin and immunoglobulin superfamily type adhesion molecules in retroocular connective tissues from patients with Graves' ophthalmopathy. 总被引:11,自引:1,他引:11
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Activation of certain adhesion molecules within vascular endothelium and the surrounding extravascular space is a critical event in the recruitment and targeting of an inflammatory response or autoimmune attack to a particular tissue site. We have recently demonstrated that the adhesion of lymphocytes to cultured retroocular fibroblasts obtained from patients with Graves' ophthalmopathy (GO) is mediated predominantly by the interaction of lymphocyte function-associated antigen-1 (LFA-1), expressed on lymphocytes, with intercellular adhesion molecule-1 (ICAM-1), expressed by these cells following exposure to interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), IL-1 alpha or purified thyroid-stimulating immunoglobulins. We now report the expression and localization in situ of several adhesion molecules, ICAM-1, endothelial leucocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion molecule-1 (VCAM-1), and LFA-3 in retroocular tissues derived from patients with severe GO (n = 4) and normal individuals (n = 3). Serial cryostat sections of tissue specimens were processed for immunoperoxidase staining using various MoAbs against ICAM-1, ELAM-1, VCAM-1 and LFA-3. In addition, consecutive sections were stained with MoAbs against LFA-1, CD45RO (UCHL-1)DR-human leucocyte antigen (HLA-DR), CD11b/CD18 (Mac-1), and CD11c/CD18 (p150,95). In GO-retroocular tissues, strong immunoreactivity for ICAM-1 and LFA-3 was detected in blood vessels (> 90%), in perimysial fibroblasts surrounding extraocular muscle fibres, and in connective tissue distinct from extraocular muscle. No ICAM-1 or LFA-3 immunoreactivity was present in extraocular muscle cells themselves. ICAM-1 and LFA-3 immunoreactivity in normal tissues was minimal or absent both in connective and muscle tissues. Vascular endothelium was strongly positive for ELAM-1 and VCAM-1 in GO-retroocular tissues, while VCAM-1 immunoreactivity was minimal (< 5% of blood vessels) and ELAM-1 immunoreactivity was generally absent in normal retroocular tissue. LFA-1-expressing, activated mononuclear cells and memory T lymphocytes (CD3+/CD45RO+) were only detected in GO-retrocular tissues, and were mainly localized around blood vessels and in areas of ICAM-1-expressing connective and perimysial tissue. HLA-DR expression was restricted to GO-tissue specimens, with strong immunoreactivity detected in blood vessels, macrophages and connective tissue and perimysial fibroblasts. No HLA-DR was detectable in extraocular muscle cells. In conclusion, infiltration of the orbit in GO by mononuclear cells, and their targeting within the orbit, may depend upon the coordinate expression of certain adhesion and MHC molecules.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
998.
Alvaro P Pinto AP Felipe F B Tuon Luiz Fernando Bleggi Torres Luiz Martins Colla?o 《Diagnostic cytopathology》2002,26(1):15-18
The present study sought possible factors leading to the cytological diagnosis of atypical squamous cells of uncertain significance (ASCUS) in cases of high-grade squamous intraepithelial lesions (HSIL). Based on retrospective histopathological analysis of loop electrical excision procedure (LEEP) products that diagnosed HSIL, two study groups were randomly selected. The first was consisted of cases with two consecutive Papanicolaou (Pap) smears with the diagnosis of ASCUS. The second (control) group was represented by cases diagnosed as HSIL by cytology. From the Pap smears diagnosed as ASCUS, the sampling limitations was different from control group (P < 0.05). The median size of the largest lesion in each case with ASCUS was 2.66 mm (+/- 1.71 mm). In the control group, the median size of the largest lesion was 5.15 mm (+/-2.58 mm) (P < 0.05). The size of the lesion and sample limitations led patients with cervical intraepithelial neoplasms to be diagnosed as ASCUS for two consecutive times, after a 6-mo period. 相似文献
999.
Growth of human connective tissue progenitor cells (CTPs) was characterized on smooth and microtextured polydimethylsiloxane (PDMS) surfaces. Human bone marrow derived cells were cultured for nine days under conditions promoting osteoblastic differentiation on Smooth PDMS and PDMS Channel microtextures (11 m high, 45 m wide channels, and separated by 5 m wide ridges). Glass tissue culture dish surfaces were used as controls. Cell numbers per colony, cell density within colonies, alignment of cells, area of colonies, and colony shapes were determined as a function of substrate surface topography. An alkaline phosphatase stain was used as a marker for osteoblastic phenotype. CTPs attached, proliferated, and differentiated on all surfaces with cell process lengths of up to 80 m. Cells on the Smooth PDMS and control surfaces spread and proliferated as colonies in proximity to other cells and migrated in random directions creating colonies that covered significantly larger areas (0.96 and 1.05 mm2, respectively) than colonies formed on PDMS Channel textures (0.64 mm2). In contrast, cells on PDMS Channel textures spread, proliferated, aligned along the channel axis, and created colonies that were more dense, and with lengths of longest colony axes that were significantly longer (3252 m) than those on the Smooth PDMS (1265 m) and control surfaces (1319 m). Cells on PDMS Channel textures were aligned at an angle of 14.44° relative to the channel axis, and the resulting colonies exhibited a significantly higher aspect ratio (13.72) compared to Smooth PDMS (1.57) and control surfaces (1.51). 相似文献
1000.
Yuri A. Zarate Luigi Boccuto Sujata Srikanth Rini Pauly Eylem Ocal Tonya Balmakund Kevin Hinkle Vikki Stefans Gerald B. Schaefer Ronnie Thomas Collins II 《American journal of medical genetics. Part A》2019,179(6):1047-1052
Kosaki overgrowth syndrome is a recently described syndrome characterized by distinctive facial features, brain white matter lesions, and developmental delay. Germline activating heterozygous PDGFRB mutations have been reported in this condition. Systemic connective tissue‐type findings have been described in some individuals. We describe a 19‐year‐old Caucasian female with a history of hydrocephalus, Dandy–Walker malformation, cervical spine arachnoid cyst, progressive scoliosis, and overgrowth. Her physical exam included distinctive craniofacial dysmorphism, as well as soft and hyperextensible skin. Cardiovascular imaging during adolescence revealed saccular aneurysms in both coronary artery systems and subtle tortuosity of the cervical vertebral arteries. Exome sequencing trio analysis identified a de novo previously reported pathogenic variant in PDGFRB, c.1696T>C (p.[Trp566Arg]). Further functional studies included platelet‐derived growth factor cellular metabolic pathway activity that confirmed the variant causes a constitutive activation of the PI3K‐AKT pathway. This is the first report to characterize the activating nature of this PDGFRB variant. We also highlight the connective tissue findings seen in Kosaki overgrowth syndrome and recommend baseline echocardiographic evaluation in all individuals with this condition with particular emphasis on coronary arteries. 相似文献