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51.
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Refinement of the 8q22.1 microdeletion critical region associated with Nablus mask‐like facial syndrome 下载免费PDF全文
53.
Dale A. Ellison Jan F. Silverman Paul H. Strausbauch Paul E. Wakely C. Tate Holbrook Vijay V. Joshi 《Diagnostic cytopathology》1996,14(2):101-107
We reviewed the cytologic features and results of ancillary studies in eight fine-needle aspiration biopsies (FNAB) performed by posterior approach in 8 patients with unresectable Wilms' tumor (WT). Chemotherapy was given following the FNAB diagnosis of WT, which was confirmed subsequently by histologic examination of surgically resected specimens. Indications for FNAB included: unresectable tumor, bilateral disease, initial presentation with metastatic disease, uncertainty regarding tumor site, and documentation of recurrence. Cytologic examination revealed blastemal cells (8/8 aspirates), spindle cells (3/8 aspirates), and epithelial differentiation or tubules (3/8 aspirates). There was no cytologic evidence of anaplasia in any of the cases. Immunocytochemical studies on cell blocks and/or smears showed cytokeratin positivity in 5/8 and vimentin positivity in 5/5 of the aspirates in which these studies were performed. Focal positivity for neuron-specific enolase (NSE) was seen in 3/3 aspirates. Stains for actin and leukocyte-common antigen were negative (0/3 and 0/2 aspirates, respectively). DNA ploidy analysis of the aspiration material by flow cytometry revealed near-diploid populations in three aspirates. Electron microscopic findings helpful for diagnosis included: cell junctions, microvilli, flocculent basement membrane-like material, cilia, autophagolysosomes, and lack of neuroectodermal differentiation. Diagnostic morphologic pitfalls for an incorrect diagnosis of neuroblastoma included nuclear molding (all aspirates), pseudorosette formation (one aspirate), and focal NSE positivity (3/3 aspirates). None of the tumors showed anaplasia on histologic examination. Cytologic recognition of the triphasic cellular components of WT (blastemal cells, spindle cells, and epithelial cells) can be helpful for a correct diagnosis; however, in 5/8 aspirates in this study, only the blastemal component was present. In these cases, immunocytochemical stains and electron microscopy proved useful in arriving at a correct FNAB diagnosis of WT. However, NSE positivity can be a pitfall for a diagnosis of neuroblastoma if the radiologic, clinical, and other cytologic features are not clearly delineated. Presence of cytokeratin and vimentin positivity would be helpful in the diagnosis of WT in such instances. Diagn Cytopathol 1996; 14:101–107. © 1996 Wiley-Liss, Inc. 相似文献
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Oligodendrocyte responses in vitro to platelet-derived growth factor (PDGF) include proliferation, survival, migration, and changes in cell morphology and molecular expression. Studies of mixed glial cultures established that astrocytes secrete PDGF; thus astrocytes are considered to be key regulators of oligodendrocyte development in vitro. We previously demonstrated PDGF α receptor mRNA expression by oligodendrocyte progenitors and preoligodendrocytes during postnatal development of rat cerebral cortex. In the present study, we have mapped the spatial and temporal expression of PDGF A-chain ligand mRNA and α receptor mRNA to determine if the cell-cell interactions that form the basis for PDGF regulation of oligodendrocyte development in vitro are also present in vivo. By in situ hybridization (ISH) we demonstrate that at embryonic day 17 (E17) cells expressing receptor mRNA (PDGFRα+) are initially in the subventricular zone, at a distance from cells expressing ligand mRNA (PDGF+) in the cortical plate. By E20 PDGFRα+ cells are found throughout the corpus callosum and cortical gray matter. PDGF+ cells are restricted to the cortical plate prenatally and only appeared in the corpus callosum postnatally. Combined immunocytochemistry and ISH demonstrated the PDGF+ cells colocalized with neurofilament, but not with GFAP. These data establish that PDGF is expressed by neurons during PDGFRα+ oligodendrocyte progenitor migration from the subventricular zone to the corpus callosum and gray matter. Furthermore, neurons continue to express PDGF during the generation and differentiation of appropriate numbers of oligodendrocytes needed to myelinate axons as the nervous system matures. © 1996 Wiley-Liss, Inc. 相似文献
55.
M. Y. Deng M. Sill D. Sturm D. Stichel H. Witt J. Ecker A. Wittmann J. Schittenhelm M. Ebinger M. U. Schuhmann D. Figarella-Branger E. Aronica O. Staszewski M. Preusser C. Haberler M. Lauten U. Schüller C. Hartmann M. Snuderl C. Dunham N. Jabado P. Wesseling M. Deckert K. Keyvani N. Gottardo F. Giangaspero K. von Hoff D. W. Ellison T. Pietsch C. Herold-Mende T. Milde O. Witt M. Kool A. Korshunov W. Wick A. von Deimling S. M. Pfister D. T. W. Jones F. Sahm 《Neuropathology and applied neurobiology》2020,46(5):422-430
56.
OBJECTIVE: To examine the frequency and reliability of depression, fatigue, and pain self-report measures in patients with systemic lupus erythematosus (SLE) and healthy controls, and to examine the relationship between a cognitive impairment index (CII) derived from the American College of Rheumatology neuropsychology research battery of tests for SLE (ACR-SLE battery) and measures of depression, pain, fatigue, and perceived cognitive dysfunction. METHODS: Thirty-one patients with SLE with a history of overt neuropsychiatric symptoms (neuropsychiatric SLE [NPSLE]), 22 patients with SLE without overt neuropsychiatric symptoms (non-NPSLE), and 25 healthy controls completed the following measures at baseline and 1-month followup: ACR-SLE battery, perceived cognitive difficulties, depression, fatigue, and pain. RESULTS: Patients with SLE (both NPSLE and non-NPSLE) showed higher symptoms of depression, higher levels of fatigue, greater pain, and more perceived cognitive problems. All measures except the Center for Epidemiologic Studies Depression scale (CES-D) demonstrated adequate reliability across the SLE groups at retest. Only patients with NPSLE had significant correlations between CII and depression, fatigue, and pain. Neither the non-NPSLE patients nor the controls had significant relationships with the CII and these behavioral measures. CONCLUSION: Patients with SLE report higher levels of cognitive difficulties, depression, pain, and fatigue compared with controls. Reliability for all measures, except the CES-D, was established in the SLE group. Overall, results suggest that cognitive dysfunction, pain, fatigue, and depression in patients with NPSLE may represent global changes in the central nervous system that require ongoing evaluation and treatment. 相似文献
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Epidermal growth factor receptor expression in pancreatic carcinoma using tissue microarray technique 总被引:10,自引:0,他引:10
BACKGROUND: The effect of overexpression of epidermal growth factor receptor (EGFR) in pancreatic carcinoma is not clear. Utilizing tissue microarrays, we evaluated EGFR expression in pancreatic cancer to determine the association of EGFR expression with histopathologic characteristics and patient outcome. METHODS: 71 cases of pancreatic adenocarcinoma and 18 cases of chronic pancreatitis were retrieved from archival files. Tissue cores from donor blocks were arrayed to create a tissue microarray. Sections were stained with EGFR and the intensity of membranous staining and percentage of tumor cells showing immunoreactivity were determined. At least 1% membranous staining and 1+ intensity were considered positive. RESULTS: EGFR was present in 49 of 71 (69%) cases of pancreatic adenocarcinoma and 7 of 18 (39%) cases of chronic pancreatitis (p = 0.03). There was no statistically significant correlation between intensity or extent of EGFR expression and tumor grade, size, or lymph node status. While median survival was nearly twice as long when EGFR was expressed (15.2 vs. 8.3 months), this did not reach statistical significance. CONCLUSIONS: EGFR is overexpressed in pancreatic cancers independent of histopathologic characteristics and does not predict survival. Immunohistochemical analysis of EGFR staining may help in identifying candidates for EGFR inhibitor therapy. 相似文献
59.
Baquet CR Mishra SI Commiskey P Ellison GL DeShields M 《Journal of the National Medical Association》2008,100(5):480-488
BACKGROUND: This study presents black-white breast cancer statistics, tumor histology and receptor status, and treatment patterns for all ages and by age groups (< 40, 40-49, and > or = 50). METHODS: The study used data from the National Cancer Institute (NCI) Surveillance, Epidemiology and End Results (SEER) program for the time period 1995-2004. Age-adjusted incidence, mortality, relative survival rates, tumor grade, histology and receptor status, and treatment patterns for invasive breast cancer were calculated for nine SEER cancer registries for 1995-2004. RESULTS: Invasive breast cancer age-adjusted incidence for black women age < 40 was significantly higher than those for white women (rate ratio = 1.16, 95% confidence interval: 1.10-1.23). Age-adjusted mortality rate for black women age < 40 was twice that for white women. Compared to white women, black women were significantly more likely to be diagnosed with regional or distant disease, have lower relative five-year survival rate and have higher likelihood of being diagnosed with tumors with poorer prognosis. Black women were less likely to receive breast cancer surgery as part of the treatment plan. CONCLUSIONS: Race/ethnic disparities in invasive breast cancer epidemiology, prognostic indicators and treatment patterns exist between black and white women. The study findings support the need for innovative research, especially on the multifaceted determinants of the differential epidemiology of breast cancer. Equally important, there is a need for evidence-guided equal delivery of quality care to eliminate breast cancer disparities among black women. 相似文献
60.
Ellison CA Makar BM Wiseman JM Gheorghiu I Taniguchi M Gartner JG 《Journal of clinical immunology》2008,28(5):600-615
INTRODUCTION: Treating recipient mice with palifermin (recombinant human keratinocyte growth factor) prevents the development of acute, lethal, graft-versus-host disease (GVHD). This is due, at least in part, to the ability of palifermin to protect epithelial cells from injury. Using the C57BL/6-->(C57BL/6 x DBA/2)F(1)-hybrid model, we previously showed that the protective effect of palifermin was also associated with redirection of the cytokine profile from Th1 to Th2. DISCUSSION: To study this immunoregulatory effect more directly, we induced acute GVH reactions in which we treated the donors rather than the recipients with palifermin. The recipient mice were protected from GVHD-associated morbidity, and their cytokine profile was predominantly Th2. The palifermin-treated donor mice alone showed a similar Th2 cytokine profile, and we observed elevated levels of thymic stromal lymphopoietin mRNA in the thymus. We further demonstrated that treating the donor mice with palifermin protects against GVHD-associated morbidity, even if the donors are deficient in Valpha14i natural killer T cells. Our findings clearly show that palifermin mediates immunoregulatory effects in addition to its cytoprotective effects and that both are likely to be involved in the mechanism through which palifermin provides protection from acute murine GVHD. 相似文献