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71.
Rony Gelman Lei Jiang Yunling E Du M Elena Martinez-Perez John T Flynn Michael F Chiang 《Journal of AAPOS》2007,11(6):532-540
PURPOSE: To measure accuracy of plus disease diagnosis by recognized experts in retinopathy of prematurity (ROP), and to conduct a pilot study examining performance of a computer-based image analysis system, Retinal Image multiScale Analysis (RISA). METHODS: Twenty-two ROP experts independently interpreted a set of 34 wide-angle retinal images for presence of plus disease. A reference standard diagnosis based on expert consensus was defined for each image. Images were analyzed by the computer-based system using individual and linear combinations of system parameters for arterioles and venules: integrated curvature (IC), diameter, and tortuosity index (TI). Sensitivity, specificity, and receiver operating characteristic areas under the curve (AUC) for plus disease diagnosis compared with the reference standard were determined for each expert, as well as for the computer-based system. RESULTS: Expert sensitivity ranged from 0.308 to 1.000, specificity ranged from 0.571 to 1.000, and AUC ranged from 0.784 to 1.000. Among individual computer system parameters, venular IC had highest AUC (0.853). Among all computer system parameters, the linear combination of arteriolar IC, arteriolar TI, venular IC, venular diameter, and venular TI had highest AUC (0.967), which was greater than that of 18 (81.8%) of 22 experts. CONCLUSIONS: Accuracy of ROP experts for plus disease diagnosis is imperfect. A computer-based image analysis system has potential to diagnose plus disease with high accuracy. Further research involving RISA system parameter cut-off values from this study are required to fully validate performance of this computer-based system compared with that of human experts. 相似文献
72.
现代管理理念已由单纯管理型向服务型转变。为了能更好地服务于临床护理人员,实现护理的科学管理,管理者必须学会运用有效的沟通技巧与护理人员进行信息及情感交流。[第一段] 相似文献
73.
74.
三七总甙对人增生性瘢痕成纤维细胞TGF-β1和细胞周期的作用 总被引:9,自引:0,他引:9
目的 观察三七总甙对人增生性瘢痕成纤维细胞TGF-β1和细胞周期的作用。方法体外培养人增生性瘢痕成纤维细胞,并应用三七总甙进行干预,用免疫细胞化学染色法结合图像分析观察TGF-β1的表达变化,用流式细胞仪测定细胞周期的变化。结果与对照组相比,三七总甙能够显著抑制细胞TGF-β1的表达,并使细胞停滞于S期,而G0-G1期、G2-M期细胞明显减少(P〈0.01)。结论三七总甙改变细胞周期和抑制增生性瘢痕成纤维细胞TGF-β1的表达,可能成为防治增生性瘢痕的药物。 相似文献
75.
76.
去带盲升结肠可控膀胱术后远期并发症(附105例报告) 总被引:2,自引:0,他引:2
目的 探讨去带盲升结肠可控膀胱术后远期并发症的发生及防治.方法 回顾性分析1995年10月至2003年1月105例去带盲升结肠可控膀胱术后患者资料.男83例,女22例.年龄32~78岁,平均60岁.随访时间9~82个月,平均40.5个月.结果 发生远期并发症27例(25.7%),其中导尿插管困难4例(3.8%),3例行尿道扩张后治愈,1例再次手术利用末段回肠重建输出道;贮尿囊结石5例(4.8%),4例行贮尿囊切开取石治愈,1例无自觉症状者未行处理;贮尿囊穿孔1例(0.9%),行手术修补后痊愈;贮尿囊过度扩张1例(0.9%),行贮尿囊缩小术;肾积水8例(7.6%),合并输尿管返流1例,合并下段输尿管狭窄4例,其中2例行狭窄段输尿管切除再吻合,1例术前为氮质血症者发展为尿毒症需行规律血透;血氯增高7例(6.7%),1例出现高氯性酸中毒需长期口服碳酸氢钠;单纯表现为症状性泌尿系感染1例(0.9%).27例中另合并症状性泌尿系感染10例,根据尿培养结果予敏感抗生素治愈.结论 去带盲升结肠可控膀胱术后远期并发症多与症状性泌尿系感染相关,积极防治泌尿系感染,规律、充分的贮尿囊冲洗及定时清洁导尿对远期并发症的预防有重要作用. 相似文献
77.
急性心肌梗死患者出现束支传导阻滞(BBB)被认为与预后差有关。这种观点在血管成形术时代是否正确尚不清楚。本研究旨在评估采用直接血管成形术治疗的急性心肌梗死伴BBB患者的预后。评估了急性心肌梗死直接血管成形术试验中3053例接受急诊导管术的患者。将入院心电图存在左束支传导阻滞的患者(LBBB,n=48,1.6%)与右束支传导阻滞患者(RBBB,n=95,3.1%)或无BBB患者(n=2910,95.3%)进行比较。具有BBB的患者年龄较大,更多见糖尿病、外周血管疾病和曾行冠状动脉搭桥术,射血分数较低,多支血管病变多见。 相似文献
78.
Interrupting reperfusion as a stroke therapy: ischemic postconditioning reduces infarct size after focal ischemia in rats. 总被引:18,自引:0,他引:18
Heng Zhao Robert M Sapolsky Gary K Steinberg 《Journal of cerebral blood flow and metabolism》2006,26(9):1114-1121
Cerebral ischemic preconditioning protects against stroke, but is clinically feasible only when the occurrence of stroke is predictable. Reperfusion plays a critical role in cerebral injury after stroke; we tested the hypothesis that interrupting reperfusion lessens ischemic injury. We found for the first time that such postconditioning with a series of mechanical interruptions of reperfusion significantly reduces ischemic damage. Focal ischemia was generated by permanent distal middle cerebral artery (MCA) occlusion plus transient bilateral common carotid artery (CCA) occlusion. After 30 secs of CCA reperfusion, ischemic postconditioning was performed by occluding CCAs for 10 secs, and then allowing for another two cycles of 30 secs of reperfusion and 10 secs of CCA occlusion. Infarct size was measured 2 days later. Cerebral blood flow (CBF) was measured in animals subjected to permanent MCA occlusion plus 15 mins of bilateral CCA occlusion, which demonstrates that postconditioning disturbed the early hyperemia immediately after reperfusion. Postconditioning dose dependently reduced infarct size in animals subjected to permanent MCA occlusion combined with 15, 30, and 60 mins of bilateral CCA occlusion, by reducing infarct size approximately 80%, 51%, and 17%, respectively. In addition, postconditioning blocked terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling-positive staining, a marker of apoptosis, in the penumbra 2 days after stroke. Furthermore, in situ superoxide detection using hydroethidine suggested that postconditioning attenuated superoxide products during early reperfusion after stroke. In conclusion, postconditioning reduced infarct size, most plausibly by blocking apoptosis and free radical generation. With further study it may eventually be clinically applicable for stroke treatment. 相似文献
79.
Lü Zhuo-ren 《中国人民解放军军医大学学报》2006,21(5)
Objective: To compare renal sodium transport, using fractional excretions of lithium(FELi) as a marker of proximal tubule sodium reabsorption, between hypertensive and non-hypertensive ouabain-treated rats and further to elucidate the role of ouabain in pathogenesis of hypertension. Methods: Thirty male Sprague-Dawley rats weighting 180-200 g were randomly divided into normal control group and ouabain treated group. Rats were infused with 1 ml/kg·d normal saline or 27. 8μg/kg·d ouabain in-traperitoneally once a day respectively. Systolic blood pressure (SBP), heart rate and body weight were recorded weekly. Rats were sacrificed 6 weeks after treatment. Blood and 24-hour urine sample were collected to measure the serum and urinary concentration of sodium, trace lithium and creatinine. Endogenous creatinine clearance rate(Ccr), fractional excretions of sodium (FENa), fractional excretions of lithium (FELi) and fractional reabsorption of sodium in the postproximal tubules (FDRNa) were calculated. Ouabain levels of plasma and renal tissue, plasma renin activity, angiotensin I and aldosterone concentration were determined. Results: 65% of the ouabain-treated rats achieved significantly higher SBP after 4 weeks, compared with that of the saline control groups or self baseline (P<0. 01). But in the other 35% of the ouabain-treated rats, their SBP was similar with control group during the experiment (P>0. 05). The body weight, heart rate and food intake between the 3 groups were no significant differences (P> 0. 05). FELi and FDRNa were significantly lower in ouabain-hypertensive group compared with ouabain-non-hypertensive group and control group(P<0. 01 and P<0. 05). The FEu and FDRn, of ouabain-nonhyper-tensive groups were similar with control group(P>0. 05). Ccr and FENa were comparable between the 3 groups (P>0. 05). Plasma and renal tissue ouabain levels, plasma renin activity, angiotensin I and aldosterone contents in ouabain-hypertensive rats were comparable with ouabain-nonhypertensive rats. Conclusion: Increase of proximal tubule sodium reabsorption play an important role in the pathogenesis of ouabain-hypertensive rats. The change of renal sodium transport may result from regulation to renal Na+ , K + -ATPase by ouabain. 相似文献
80.
阻塞性黄疸大鼠肾脏自分泌内皮素的变化及其与肾功能损害的关系 总被引:3,自引:1,他引:2
目的 探讨阻塞性黄疸时肾脏自分泌内皮素 (ET)的变化及其与肾功能损害的关系。方法 结扎胆总管(BDL)制备阻塞性黄疸大鼠模型 ,作为实验组 ,对照组鼠仅行假手术。分别于术后 5、1 0及 1 5d ,两组各取 1 0只大鼠检测其肾脏对氨基马尿酸清除率 (CPAH)、菊粉清除率 (CIN)和钠排泄分数 (FENa+) ,并用鲎试剂法测定血浆内毒素 (EX)水平 ,放射免疫法测定肾动、静脉血浆及肾组织中ET 1含量。结果 ①实验组术后 5d仅FENa+明显高于对照组 (P<0 .0 1 ) ,术后 1 0d起 ,CPAH、CIN及FENa+呈进行性下降 ,术后 1 5dFENa+已较对照组低 ,与对照组比较差异有显著性 (P<0 .0 1 ) ;②实验组术后血浆EX水平呈进行性升高 ,与对照组比较差异有显著性 (P<0 .0 1 ) ;③实验组术后肾动脉血浆ET 1水平呈持续性降低 ,而肾静脉血浆及肾组织中ET 1含量呈持续性升高 ,与对照组比较差异有显著性 (P<0 .0 1 ) ;④血浆EX水平与肾组织ET 1含量呈正相关 (r =0 .762 4 ,P<0 .0 1 ) ,肾组织ET 1含量与CPAH和CIN呈负相关 (r=- 0 .883 2 ,P<0 .0 1 ;r =- 0 .945 2 ,P<0 .0 1 )、与FENa+呈正相关 (r=0 .873 4 ,P<0 .0 1 )。结论 内毒素血症及其诱导的肾内ET分泌增加在阻塞性黄疸所致大鼠肾损害中可能具有重要作用 相似文献