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11.
An 80-year-old man was evaluated for an epibulbar tumor on a phthisical eye. The initial biopsy diagnosis of the epibulbar tumor was poorly differentiated neoplasm. Exenteration of the phthisical eye and orbital contents showed an extensive pleomorphic adenocarcinoma of the nonpigmented epithelium of the ciliary body with extraocular extension. There was evidence of hyaluronic acid secretion and immunohistochemical staining was strong for vimentin, focal for epithelial membrane antigen and S-100 protein, and weak for neuron-specific-enolase. Electron microscopy demonstrated desmosomes between tumor cells, areas of thick, multilaminar basement membrane production surrounding individual tumor cells, and occasional intracytoplasmic intermediate filaments. 相似文献
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M N Burnier I W McLean L E Zimmerman S H Rosenberg 《Investigative ophthalmology & visual science》1990,31(10):2037-2040
In 150 retinoblastomas the authors found a uniform thickness of the cuff of viable retinoblastoma cells that surrounds blood vessels. The mean thickness was 98.7 microns with a standard deviation of 11.9 microns. The cross-sectional area of the cuff was negatively correlated with the mitotic activity in the cuff and positively correlated with the diameter of the central vessel. The mitotic activity in the cuff of cells was inversely related to the distance from the central blood vessel. When the cuff was divided into three concentric rings, the inner ring contained a mean of 6.2 mitotic figures, the middle ring contained a mean of 2.9 mitotic figures, and the outer ring contained a mean of 0.6 mitotic figures. This pattern of growth is similar to that observed in other rapidly growing neoplasms in humans and experimental animals. In these tumors this pattern results from reduction in oxygen tension with increased distance from the central blood vessel. 相似文献
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Comparison between the prevalence and treatment of wheezing and coughing in Brampton and Mississauga children 总被引:1,自引:0,他引:1
An analysis of hospital discharge data showed that Brampton children 4 years and under had higher rates of hospital admissions for asthma, bronchitis and upper respiratory infections than children in the same age group living in Mississauga and other Ontario municipalities. The present study was done to compare the prevalence and treatment of wheezing and coughing between Brampton and Mississauga children 4 and 5 years of age. The study showed that increased use of pediatricians on the part of Mississauga children in comparison to Brampton children resulted in a higher proportion being placed on anti-asthmatic medications even though the underlying prevalence rate of wheezing and coughing was the same in the two samples. Further study is required to determine whether differences in primary care between the two samples can explain a two-fold increase in hospital admission rates for lower respiratory illness among Brampton preschool children in comparison to their counterparts in Mississauga. 相似文献
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大鼠心肌缺血再灌注时心肌细胞凋亡caspase-3活性变化规律及药物对其影响 总被引:3,自引:2,他引:1
目的 探讨大鼠心肌缺血再灌注 (Ischemiareperfusion ,IR)不同时相的心肌细胞凋亡、caspase 3活性变化规律及caspase 3抑制剂Ac DEVD CHO的影响。方法 Wistar大鼠 12 2只 ,设立IR组 ,IR +Ac DEVD CHO组和假手术对照组并分设缺血 3 0min后再灌注 1、3、6、12、2 4h 5个时相点 ;以缺口末端标记法 (TUNEL)标记凋亡细胞 ,用荧光分析法检测caspase 3活性 ,行TTC染色测定心肌梗死范围。结果 心肌细胞凋亡与caspase 3活性随心肌再灌注不同时相而变化 ,心肌细胞凋亡指数 (Apoptosisindex ,AI)与caspase 3活性于再灌注 12h最高 [AI :( 3 4 83± 9 3 5 ) % ;caspase 3活性 :( 1 3 4±0 2 ) ] ,其后基本维持在平台状态 ;心肌梗死范围随IR时间逐渐增加 ,至 2 4h仍未见下降趋势 ,三者间呈显著正相关 (P <0 0 5 )。IR +Ac DEVD CHO组上述指标虽也明显增高 ,但比IR组明显减小 (P <0 0 5 )。结论 Caspase 3激活及心肌细胞凋亡参与了心肌缺血再灌注损伤过程 ,Ac DEVD CHO减轻心肌缺血再灌注损伤可能部分与其抑制心肌细胞凋亡有关。 相似文献
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André H. Eriksson Manthena V.S. Varma Everett J. Perkins Cheryl L. Zimmerman 《Journal of pharmaceutical sciences》2010,99(3):1574-1581
LY354740 is a potent mGlu2/3 agonist with a limited oral bioavailability. Its alanyl prodrug, LY544344, showed high affinity to the intestinal peptide transporter PEPT1, and improved the oral bioavailability of LY354740 in various animal models. The aim of the present study was to investigate the mechanism of in vivo absorption of the dipeptidic prodrug LY544344. The permeabilities of LY544344 and LY354740 were examined in the rat in situ single‐pass intestinal perfusion model. The intestinal absorptive flux of LY354740 was shown to be very low in comparison with LY544344. The absorptive flux of LY544344 could best be described by a Michaelis–Menten process in parallel with a linear process. The estimated parameters were: Jmax = 26.7 × 10?5 µmol/(cm2‐s), Km = 2.6 mM. The absorptive permeability of LY544344 was reduced to approximately 5% of control in the presence of excess Gly‐Sar, a known PEPT1 substrate. Intracellular accumulation of LY354740 and LY544344, estimated postperfusion, showed high levels of LY354740 over LY544344 at all perfusate concentrations studied. However, there was a decline in the intracellular ratio of LY354740 to LY544344 at higher concentrations, suggesting that the metabolic activation to release LY354740 is saturable. © 2009 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1574–1581, 2010 相似文献
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A woman with severe cicatricial conjunctival changes secondary to allopurinol-induced Stevens-Johnson syndrome developed bilateral palpebral conjunctival cysts. Pathologic examination of these lesions revealed respiratory-like pseudostratified ciliated epithelium in the walls of several cysts of one eye. To our knowledge, this is the first report of this phenomenon. 相似文献