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81.
固生蛋白tenascin对肝细胞癌血管生成及浸润转移的影响 总被引:1,自引:0,他引:1
目的 探讨固生蛋白(tenascin ,TN)在肝细胞癌(hepatocellularcarcinoma ,HCC)中的表达和与HCC血管生成及浸润转移的关系。方法 应用免疫组织化学法检测4 2例HCC、10例肝硬化和7例正常肝组织内TN的表达情况,观察与HCC病理学特点及微血管密度(microvesseldensity ,MVD)之间的关系。结果 ①TN在HCC中的阳性表达率和强度显著高于肝硬化和正常肝脏组织( χ2 =4 15 ,P <0 0 5 ;t=2 4 73,P <0 0 5 ) ;②TN在有包膜侵犯组、病理分级Ⅲ~Ⅳ组及有转移HCC中的阳性表达率及强度明显高于无包膜侵犯组( χ2 =5 4 7,P <0 0 5 ;t=2 138,P <0 0 5 )、病理分级Ⅰ~Ⅱ级组( χ2 =6 87,P <0 0 1;t=2 4 79,P <0 0 5 )以及无转移组( χ2 =10 6 ,P <0 0 1;t=2 6 93,P <0 0 1) ;③肝癌>5cm、有包膜侵犯、有转移、病理分级Ⅲ~Ⅳ级组的MVD值明显高于肝癌≤5cm(t=2 0 36 ,P <0 0 5 )、无包膜侵犯(t =2 32 8,P <0 0 5 )、无转移(t =2 4 94 ,P <0 0 5 )及病理分级Ⅰ~Ⅱ级组(t =2 2 71,P <0 0 5 )。④TN阳性表达HCC中的MVD值明显高于TN阴性表达HCC中的MVD值(t =2 4 87,P <0 0 5 )。结论 TN在HCC组织中的表达上调与其血管生成和浸润转移有关 相似文献
82.
低位无肛术术中完整保留瘘口组织的必要性和可行性 总被引:2,自引:0,他引:2
目的探讨低位肛门直肠畸形术术中保留瘘口组织的必要性和可行性。方法对67例无肛前庭及会阴瘘患儿的临床资料进行回顾性分析。其中女童无肛前庭瘘59例,男童无肛会阴瘘8例。年龄3个月~16岁,平均10个月。患儿多以排便困难或肛门位置异常就诊。4例无肛前庭瘘患儿曾在婴儿期行瘘口后切术。患儿均采用完整保留瘘口的前矢状入路肛门成形术治疗。结果患儿术后3及6个月常规来院复诊,最长随访8年。65例(97.0%)患儿会阴部矢状切口一期愈合,会阴及肛门外观良好;另2例(男、女各1例)术中直肠破损患儿,自修补处穿孔导致会阴部矢状切口感染(占直肠破损修补术的40%),最终形成直肠会阴瘘,但肛门外观良好。67例均采用肛门功能临床评分标准评估患儿排便功能,64例(95.5%)患儿排便功能良好,总评分为5~6分;另3例(男1例,女2例)顽固便秘,需开塞露协助排便。结论低位无肛术中完整保留瘘口组织非常必要。 相似文献
83.
Eli Peli 《Ophthalmic & physiological optics》2005,25(6):543-555
Subjects with central field loss (CFL) individually selected enhancement parameters to improve visibility of static video images. The effect of enhancement on performance and on perceived quality of motion video was assessed. Performance, e.g. recognition of visual details, was assessed by having subjects answer questions regarding visual information contained in the video motion segments that were enhanced using the individually-selected parameters. Enhancement did not improve subject performance on questions about video content. This result might be due to a ceiling effect limitation of the performance assessment method. In a second procedure, subjects' continuous perceptions of quality (using an adjective-based rating scale) were made while the enhancement parameters were abruptly switched among multiple values; these included the individually-selected enhancements, as well as unenhanced, over-enhanced, and degraded segments. The results indicate that adaptive enhancement (individually-tuned using a static image) adds significantly to perceived image quality when viewing motion video. Subjects who selected stronger contrast enhancement also perceived the enhancement to provide a larger benefit in image quality. 相似文献
84.
浅谈电子文档的原始性和真实性及法律证据作用 总被引:3,自引:0,他引:3
董中印 《安徽卫生职业技术学院学报》2005,4(2):62-63,57
该文针对电子文件或档案的原始性真实性与电子档案的法律证据作用,参考了最新的研究结果,并提出了自己的思考,逐步探讨了它们的涵义及关系. 相似文献
85.
目的探讨低密度及氧化低密度脂蛋白对内皮细胞分泌肾上腺髓质素(ADM)的影响.方法利用培养的内皮细胞株ECV-304细胞,分别与不同浓度的低密度(50 100mg/L)、氧化低密度脂蛋白(50 100mg/L)及低密度脂蛋白(50 mg/L) 氧化低密度脂蛋白(50 mg/L)进行孵育,24 h后分别收集培养上清及细胞,用放免分析检测上清及细胞内肾上腺髓质素的含量.结果低密度脂蛋白对肾上腺髓质素的分泌无影响,而氧化型低密度脂蛋白能明显刺激ADM的分泌,二者合用的作用接近于100mg/L的OX-LDL.结论OX-LDL可能具有氧化LDL使其成为OX-LDL的作用,ADM的分泌可能是对细胞损伤的一种反应. 相似文献
86.
Roopa Thukaram William A Suarez Sreekanthan Sundararaghavan 《Catheterization and cardiovascular interventions》2005,66(1):18-20
A symptomatic 1,400 g premature triplet underwent successful transcatheter coil embolization of patent arterial duct using the umbilical artery. One 3 mm x 3 cm Flipper coil was used with no angiographic residual shunt. To the best of our knowledge, this is one of the smallest preterm infants to undergo this transcatheter procedure. 相似文献
87.
Christina Djokoto George Tomlinson Stephen Waldman Marc Grynpas Angela M. Cheung 《Journal of clinical densitometry》2004,7(4):448-456
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS. 相似文献
88.
Xiao-Mei Mai Per-Olof Gäddlin Lennart Nilsson Ingemar Leijon 《Pediatric allergy and immunology》2005,16(5):380-385
Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness. 相似文献
89.
目的 :探讨胃癌组织中微血管密度 (MVD)与胃癌生物学行为的关系。方法 :应用免疫组织化学S -P法和抗人因子Ⅷ相关抗原 (FⅧ -RAg)的抗体 ,标记 6 8例胃癌组织中的微血管 ,检测MVD。分析其与胃癌组织学类型、分化水平、浸润深度及淋巴结转移的关系。结果 :6 8例胃癌组织中FⅧ -RAg阳性表达 5 2例 ,占 76 .4 7%。FⅧ -RAg和MVD与分化水平、浸润深度 (P <0 .0 1)及淋巴结转移 (P <0 .0 0 1)密切相关。不同组织学类型中FⅧ-RAg的表达具有显著相关性 (P <0 .0 1) ,而MVD则与胃癌组织学类型无显著差异 (P >0 .0 5 )。 结论 :血管生成对胃癌的发展具有一定作用 ,FⅧ -RAg的检测和MVD可作为判断胃癌恶性程度和预后的生物学指标。 相似文献
90.
安徽省学生近20年常见病患病情况分析 总被引:4,自引:1,他引:3
目的了解安徽省学生视力低下、龋齿、贫血的患病状况及变化趋势,为开展学生常见病防治工作提供参考。方法对1985,1995,2000,2005年4个不同时期安徽省学生体质健康调研资料7~22岁学生视力低下、龋齿、贫血等常见病的患病状况进行分析。结果20a间,学生贫血患病率明显下降,从1985年的55.5%下降到2005年的5.3%;龋患率1985年至2000年明显上升,从32.1%上升到42.6%,2000年以后呈下降趋势,达18.8%;近视率逐年上升并居高不下,从1985年的23.0%上升到2005年的55.2%,尤其是高中生和大学生,高达70%~80%。结论通过开展学生常见病防治工作,学生贫血患病率和龋患率明显下降,但学生近视率逐年上升并居高不下,应引起有关部门的重视。 相似文献