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41.
目的研究小细胞肺癌(SCLC)和非小细胞肺癌(NSCLC)的分类问题。方法217例肺癌患者.其中男性165例.殳性52例;年龄35~80岁,平均年龄61.5岁。其中SCLC108例,NSCLC109例。提取患者764幅肺癌CT图像的灰度共生矩阵,选取对比度、熵、能量和逆差矩4个特征值,借助临床确诊结果,利用多层前向(BP)、径向基函数(RBF)人工神经网络对特征进行训练测试。结果BP人工神经网络对10%的78例样本进行测试,SCLC42例预测正确.NSCLC33例预测正确.3例预测失败。RBF神经网络对10%的78例测试样本进行测试,SCLC42例预测正确.NSCLC36例预测正确、类似方法对样本总数的70%进行训练,用30%的230例进行测试;BP人工神经网络有209例预测正确。正确率为90.9%:其中SCLC111例预测正确,正确检出率为88.8%;NSCLC98例预测正确,正确检出率为93.3%。RBF人工神经网络有216例预测正确.正确率为93.9%,其中SCLC117例预测正确,正确率为93.6%;NSCLC99例预测正确,止确检出率为94.3%。可见BP、RBF人1二神经网络对SCLC和NSCLC均具有90%以上的正确率,高于人工诊断结果。结论基于灰度共生矩阵的对比度、熵、能量和逆差矩4个特征值能反映SCLC和NSCLC的有效特征参量.通过人工神经网络能达到分类目的,辅助临床治疗。  相似文献   
42.
目的 评价iRoot BP Plus用于成熟恒牙活髓保存治疗(直接盖髓术和部分活髓切断术)的临床疗效.方法 选取120例共120颗因龋露髓成熟恒牙牙髓炎患者,随机分为A(直接盖髓术)、B(部分活髓切断术)和C(根管治疗术)3组,每组40例,术后第3、6、12个月复查,综合评价3组的疗效、发生不良反应和患者满意度的差异.结果 3组患牙治疗效果均较好:术后3个月,A、B、C组的治疗成功率分别是92.5%、97.5%、95.0%;术后6个月,3组分别是90.0%、95.0%、92.5%;术后12个月,3组分别是90.0%、95.0%、90.0%.在不同时间段,3组之间治疗的成功率和术后不良反应发生率的差异均无统计学意义(P>0.05).A、B两组的患者综合满意度明显高于C组(P<0.05).结论 iRoot BP Plus用于因龋露髓的成熟恒牙活髓保存治疗,疗效可靠,可以避免根管治疗所产生的术后并发症,值得临床推广.  相似文献   
43.
Excessive sodium intake is associated with both hypertension and an increased risk of cardiovascular events, presumably because of an increase in extracellular volume. The extent to which sodium intake affects extracellular volume and BP varies considerably among individuals, discriminating subjects who are salt-sensitive from those who are salt-resistant. Recent experiments have shown that, other than regulation by the kidney, sodium homeostasis is also regulated by negatively charged glycosaminoglycans in the skin interstitium, where sodium is bound to glycosaminoglycans without commensurate effects on extracellular volume. The endothelial surface layer is a dynamic layer on the luminal side of the endothelium that is in continuous exchange with flowing blood. Because negatively charged glycosaminoglycans are abundantly present in this layer, it may act as an intravascular buffer compartment that allows sodium to be transiently stored. This review focuses on the putative role of the endothelial surface layer as a contributor to salt sensitivity, the consequences of a perturbed endothelial surface layer on sodium homeostasis, and the endothelial surface layer as a possible target for the treatment of hypertension and an expanded extracellular volume.  相似文献   
44.
目的 分析BP与T2DM患者尿白蛋白/肌酐(UACR)的关系,探讨BP对糖尿病慢性肾脏疾病(CKD)的影响. 方法 收集330例T2DM患者资料,测BP和UACR.根据UACR水平分为<30mg/24 h组、30~299mg/24 h组和≥300mg/24 h组,检测各组BP及UACR等水平的变化情况.结果 正常血压组及高血压组蛋白尿发生率为31.4%及64.2%.病程<10年、病程10~20年及病程>20年正常血压者与高血压者比较,总蛋白尿的发生率分别为0%、8%,7.6%、30.1%,0%及51.7%(P<0.01).UACR<30 mg/24 h组、≥300mg/24 h组高血压发生率为30.3%及69.1%;病程<10年、病程10~20年及病程>20年患者中<30mg/24 h组、30~299mg/24 h组和≥300mg/24 h组比较,高血压发生率分别为28.9%、67.4%、100%,33.3%、50.9%、76.7%,25.0%、84.6%和100% (P<0.01). 结论 高血压加速CKD的发生.  相似文献   
45.
PurposeVascular risk factors in midlife may play a role in the development of cognitive decline, dementia and Alzheimer’ disease (AD). The role of serum total cholesterol has yielded inconsistent results in diverse cohorts.ObjectiveTo analyze the relationship between the midlife cholesterol level and AD in late life in a homogenous cohort of Caucasian men.MethodsThe Helsinki Businessmen Study is a cohort of male business executives who have been followed-up since 1964. Midlife cholesterol level was available in 3293 men, of whom 205 developed a register-verified AD. Cognitively intact men in 2007 (n = 844) served as controls, and logistic regression adjusted for age and cardiovascular risk factors was used to investigate the association between cholesterol and AD.ResultsAt baseline, the men with subsequent AD diagnosis had 0.4 mmol/L higher total cholesterol level than controls (6.7 vs 6.3 mmol/L). In adjusted analyses 1 mmol/L rise in total cholesterol was associated with a 22% increased risk of AD (odds ratio [OR] 1.22, 95% confidence interval 1.06 to 1.40, P = 0.005). Risk of AD (OR with 95% CI) also increased in a stepwise manner from the lowest to highest quartile of midlife cholesterol from 1.0 (referent) to 1.6 (1.01–2.6), 1.9 (1.2–3.0), and 2.0 (1.2–3.3), respectively.ConclusionIn this longitudinal study with up to 43 years of follow-up, higher serum total cholesterol in early midlife was clearly associated with a higher risk of AD in late life.  相似文献   
46.
47.
ObjectivesThis study sought to evaluate pattern and clinical correlates of change in left ventricular (LV) geometry over a 4-year period in the community; it also assessed whether the pattern of change in LV geometry over 4 years predicts incident cardiovascular disease (CVD), including myocardial infarction, heart failure, and cardiovascular death, during an additional subsequent follow-up period.BackgroundIt is unclear how LV geometric patterns change over time and whether changes in LV geometry have prognostic significance.MethodsThis study evaluated 4,492 observations (2,604 unique Framingham Heart Study participants attending consecutive examinations) to categorize LV geometry at baseline and after 4 years. Four groups were defined on the basis of the sex-specific distributions of left ventricular mass (LVM) and relative wall thickness (RWT) (normal: LVM and RWT <80th percentile; concentric remodeling: LVM <80th percentile but RWT ≥80th percentile; eccentric hypertrophy: LVM ≥80th percentile but RWT <80th percentile; and concentric hypertrophy: LVM and RWT ≥80th percentile).ResultsAt baseline, 2,874 of 4,492 observations (64%) had normal LVM and RWT. Participants with normal geometry or concentric remodeling progressed infrequently (4% to 8%) to eccentric or concentric hypertrophy. Change from eccentric to concentric hypertrophy was uncommon (8%). Among participants with concentric hypertrophy, 19% developed eccentric hypertrophy within the 4-year period. Among participants with abnormal LV geometry at baseline, a significant proportion (29% to 53%) reverted to normal geometry within 4 years. Higher blood pressure, greater body mass index (BMI), advancing age, and male sex were key correlates of developing an abnormal geometry. Development of an abnormal LV geometric pattern over 4 years was associated with increased CVD risk (140 events) during a subsequent median follow-up of 12 years (adjusted-hazards ratio: 1.59; 95% confidence interval: 1.04 to 2.43).ConclusionsThe longitudinal observations in the community suggest that dynamic changes in LV geometric pattern over time are common. Higher blood pressure and greater BMI are modifiable factors associated with the development of abnormal LV geometry, and such progression portends an adverse prognosis.  相似文献   
48.
49.
ObjectivesThe aim of this study was to investigate the hypothesis that a novel biodegradable polymer–coated, cobalt-chromium (CoCr), sirolimus-eluting stent (BP-SES) is noninferior in safety and efficacy outcomes compared with a durable polymer (DP)-SES.BackgroundNo randomized trials have the compared safety and efficacy of BP-SES versus DP-SES on similar CoCr platforms, thereby isolating the effect of the polymer type.MethodsIn this prospective, single-blind, randomized trial conducted at 32 Chinese sites, 2,737 patients eligible for coronary stenting were treated with BP- or DP-SES in a 2:1 ratio. The primary endpoint was 12-month target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, or clinically indicated target lesion revascularization. Secondary endpoints included TLF components, and definite/probable stent thrombosis.ResultsAt 12 months, the difference in the primary endpoint of TLF between BP-SES (6.3%) and DP-SES (6.1%) groups was 0.25% (95% confidence interval: −1.67% to 2.17%, p for noninferiority = 0.0002), demonstrating noninferiority of BP-SES to DP-SES. Individual TLF components of cardiac death (0.7% vs. 0.6%, p = 0.62), target vessel myocardial infarction (3.6% vs. 4.3%, p = 0.39), and clinically indicated target lesion revascularization (2.6% vs. 2.2%, p = 0.50) were similar, as were low definite/probable stent thrombosis rates (0.4% vs. 0.6%, p = 0.55).ConclusionsIn this large-scale real-world trial, BP-SES was noninferior to DP-SES for 1-year TLF. (Evaluate Safety and Effectiveness of the Tivoli ® DES and the Firebird ® DES for Treatment of Coronary Revascularization; NCT01681381)  相似文献   
50.
《中国现代医生》2020,58(10):77-80+95
目的 探讨显微根尖外科手术中iRoot BP Plus倒充填和Bio-Oss植骨在治疗慢性根尖周病变的临床效果。方法 选取2015年10月~2018年1月期间收治的慢性根尖周炎共计126颗患牙作为研究对象,按是否进行iRoot BP Plus根管倒充填和Bio-Oss植骨修复缺损分为三组。术后复查,通过临床检查和X线片评定结果,分析临床疗效。结果 术后12个月根尖手术中行iRoot BP Plus和Bio-Oss联合应用组治疗成功率达97.62%,iRoot BP Plus治疗组未行Bio-Oss植骨组的治疗成功率达80.95%,而单纯根尖手术治疗组治疗成功率仅为54.76%,组间差异有统计学意义(P0.05)。结论 显微根尖外科手术中iRoot BP Plus倒充填联合Bio-Oss植骨具有良好的临床效果。  相似文献   
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