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排序方式: 共有665条查询结果,搜索用时 46 毫秒
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Yu-Te Hsu Mt Hartstein Alexander J. Davies Alexander J. Hickey Mun K. Chan Juan Porras Toshinao Loew Sofia V. Taylor Hsu Liu Alexander G. Eaton Matthieu Le Tacon Huakun Zuo Jinhua Wang Zengwei Zhu Gilbert G. Lonzarich Bernhard Keimer Neil Harrison Suchitra E. Sebastian 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(7)
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Peter P Stanich Robert Pilarski Jonathan Rock Wendy L Frankel Samer El-Dika Marty M Meyer 《World journal of gastroenterology : WJG》2014,20(7):1833-1838
AIM:To investigate our clinical experience with the colonic manifestations of phosphatase and tensin homolog on chromosome ten(PTEN)hamartoma tumor syndrome(PHTS)and to perform a systematic literature review regarding the same.METHODS:This study was approved by the appropriate institutional review board prior to initiation.A clinical genetics database was searched for patients with PHTS or a component syndrome that received gastrointestinal endoscopy or pathology interpretation at our center.These patient’s records were retrospectively reviewed for clinical characteristics(including family history and genetic testing),endoscopy results and pathology findings.We also performed a systematic review of the literature for case series of PHTS or component syndromes that reported gastrointestinal manifestations and investigations published after consensus diagnostic criteria were established in 1996.These results were compiled and reported.RESULTS:Eight patients from our institution met initial inclusion criteria.Of these,5 patients underwent4.2 colonoscopies at mean age 45.8±10.8 years.All were found to have colon polyps during their clinical course and polyp histology included adenoma,hyperplastic,ganglioneuroma and juvenile.No malignant lesions were identified.Two had multiple histologic types.One patient underwent colectomy due to innumerable polyps and concern for future malignant potential.Systematic literature review of PHTS patients undergoing endoscopy revealed 107 patients receiving colonoscopy at mean age 37.4 years.Colon polyps were noted in92.5%and multiple colon polyp histologies were reported in 53.6%.Common polyp histologies included hyperplastic(43.6%),adenoma(40.4%),hamartoma(38.3%),ganglioneuroma(33%)and inflammatory(24.5%)polyps.Twelve(11.2%)patients had colorectal cancer at mean age 46.7 years(range 35-62).Clinical outcomes secondary to colon polyposis and malignancy were not commonly reported.CONCLUSION:PHTS has a high prevalence of colon polyposis with multiple histologic types.It should be considered a mixed polyposis syndrome.Systematic review found an increased prevalence of colorectal cancer and we recommend initiating colonoscopy for colorectal cancer surveillance at age 35 years. 相似文献
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In-Nam HWANG Sung-Ok HONG Bin-Na LEE Yun-Chan HWANG Won-Mann OH Hoon-Sang CHANG 《Journal of applied oral science : revista FOB》2012,20(5):576-580
Objective
The aim of this study was to evaluate the effect of multiple layers of an infection control barrier on the micro-hardness of a composite resin.Material and Methods
One, two, four, and eight layers of an infection control barrier were used to cover the light guides of a high-power light emitting diode (LED) light curing unit (LCU) and a low-power halogen LCU. The composite specimens were photopolymerized with the LCUs and the barriers, and the micro-hardness of the upper and lower surfaces was measured (n=10). The hardness ratio was calculated by dividing the bottom surface hardness of the experimental groups by the irradiated surface hardness of the control groups. The data was analyzed by two-way ANOVA and Tukey''s HSD test.Results
The micro-hardness of the composite specimens photopolymerized with the LED LCU decreased significantly in the four- and eight-layer groups of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. The hardness ratio of the composite specimens was <80% in the eight-layer group. The micro-hardness of the composite specimens photopolymerized with the halogen LCU decreased significantly in the eight-layer group of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. However, the hardness ratios of all the composite specimens photopolymerized with barriers were <80%.Conclusions
The two-layer infection control barrier could be used on high-power LCUs without decreasing the surface hardness of the composite resin. However, when using an infection control barrier on the low-power LCUs, attention should be paid so as not to sacrifice the polymerization efficiency. 相似文献27.
Condino-Neto A Franco JL Espinosa-Rosales FJ Leiva LE King A Porras O Oleastro M Bezrodnik L Grumach AS Costa-Carvalho BT Sorensen RU 《Allergologia et immunopathologia》2012,40(3):187-193
Primary immunodeficiency diseases (PIDD) are associated with significant morbidity and mortality and result in a significant public health burden. This is in part due to the lack of appropriate diagnosis and treatment of these patients. It is critical that governments become aware of this problem and provide necessary resources to reduce this impact on health care systems. Leading physicians in their respective countries must be supported by their own governments in order to implement tools and provide education and thus improve the diagnosis and treatment of PIDD. The Latin American Society of Primary Immunodeficiencies (LASID) has initiated a large number of activities aimed at achieving these goals, including the establishment of a PIDD registry, development of educational programmes and guidelines, and the introduction of a PIDD fellowship programme. These initiatives are positively impacting the identification and appropriate treatment of patients with PIDD in Latin America. Nevertheless, much remains to be done to ensure that every person with PIDD receives proper therapy. 相似文献
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糙叶五加茎化学成分研究 总被引:2,自引:2,他引:0
目的基于脂多糖(LPS)诱导的巨噬细胞RAW264.7和小胶质细胞BV2为生物活性导向模型研究糙叶五加Acanthopanax henryi茎的化学成分。方法采用硅胶柱色谱、凝胶柱色谱、制备薄层及重结晶等方法进行分离纯化,利用波谱分析结合理化性质鉴定化合物的结构。结果从糙叶五加茎甲醇提取物的醋酸乙酯萃取部位中分离得到18个化合物,分别鉴定为对羟基苯甲酸(1)、反式对羟基肉桂酸(2)、反式咖啡酸甲酯(3)、咖啡酸(4)、反式松柏醛(5)、丁香醛(6)、香草醛(7)、6-甲氧基-7-羟基香豆素(8)、反式芥子醛(9)、十一烷二酸单甲酯(10)、(-)-芝麻素(11)、3-O-咖啡酰奎宁酸(12)、5-O-咖啡酰奎宁酸(13)、1,3-双咖啡酰奎宁酸(14)、1,4-双咖啡酰奎宁酸(15)、1,5-双咖啡酰奎宁酸(16)、豆甾醇(17)、β-谷甾醇(18)。结论化合物10为首次从五加科植物中分离得到;除化合物12、14、17、18外,其他化合物均为首次从该植物中分离得到。 相似文献
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Federico J. Yazyi Carlos M. Canullan Nicolas F. Baglietto Roberto F. Klappenbach Facundo Alonso Quintas Juan Alvarez Rodriguez Luis T. Chiappetta Porras 《International journal of surgery case reports》2014,5(12):1234-1237