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1.
超声彩色多普勒对糖尿病眼部血管血流动力学的研究 总被引:1,自引:0,他引:1
目的:探讨2型糖尿病患者眼底动脉血流动力学变化与糖尿病视网膜病变发生发展的关系。方法:应用彩色多普勒超声检测75例(150只眼)2型糖尿病患者视网膜中央动脉(CRA)、睫状后动脉(PCA)、眼动脉(OA)的最大收缩期血流速度(PSV)、舒张末期血流速度(EDV)、阻力指数(RI),按眼底病变分为无视网膜病变(NDR)、视网膜病变非增殖期(NPDR)、视网膜病变增殖期(PDR)3组,并与正常对照组53例(106只眼)进行对照。结果:病变组眼部血管CRA、PCA、OA的PSV、EDV呈进行性下降趋势,RI呈进行性升高趋势。NDR组CRA、PCA、OA的EDV及RI与对照组相比差别有统计学意SL(P〈0.05)。结论:彩色多普勒超声能较准确反映糖尿病眼部血管改变,对早期发现视网膜血流动力学改变有重要价值。 相似文献
2.
彩色多普勒能量显像对糖尿病视网膜病变眼血流动力学的研究 总被引:1,自引:0,他引:1
目的应用彩色多普勒能量显像(color doppler energy,CDE)技术检测糖尿病视网膜病变患者的眼球血流动力学变化。方法利用CDE技术,测定100例(200只眼)糖尿病视网膜病变患者及15例(30只眼)正常人眼动脉(ophthalmic artery,OA)及视网膜中央动脉(central retinal artery,CRA)的收缩期峰值流速(peak systolic velocity,PSV)、舒张末期峰值流速(end diastolic velocity,EDV)及阻力指数(resistive index,RI)。经眼底检查和眼底荧光造影检查,包括无明显视网膜病变(non-obvious diabetic retinopathy,NDR)25例,非增殖期糖尿病视网膜病变(non-pro-liferative diabetic retinopathy,NPDR))39例,增殖期糖尿病视网膜病变(proliferative diabetic retinopathy,PDR)36例。结果与对照组比较,病例组OA的EDV明显减小,RI明显增大,差异有显著性(P〈0.05),而PSV差异没有显著性(P〉0.05)。病例组CRA的PSV、EDV明显减小,RI明显增大,差别有显著性(P〈0.05)。EDV和RI的灵敏度优于PSV。结论随着糖尿病视网膜病变发展,糖尿病患者的眼球血流动力学发生进行性改变,应用CDE动态检测眼球血管血流动力学的变化对DRP的发病机制研究及早期诊治、预后具有重要临床意义。 相似文献
3.
目的:观察糖尿病视网膜病变眼血流动力学的改变情况。方法:利用彩色多普勒超声诊断仪(color Doppler imagining,CDI)测定32例(64只眼)糖尿病视网膜病变(diabetic retinopathy,DR)患者球后血流状态,并与正常人30例(60只眼)进行对照。其中32例DR患者接受了荧光素眼底血管造影(fundusfluorescein angiography,FFA)检查,包括非增殖型(NPDR)20例和增殖型(PDR)12例。结果:DR与正常对照组相比,眼动脉(OA)、视网膜中央动脉(CRA)的最大收缩期血流速度(PSV)、舒张末期血流速度(EDV)和总平均速度(Vm)均降低,搏动指数(PI)和阻力指数(RI)增高,视网膜中央骨静脉(CRV)的最大血流速度(Vmax)、最低血流速度(Vmin)和Vm增高,其中NPDR各数值比较具有统计学意义(P<0.05),PDR各数值比较差异有统计学意义(P<0.01)。结论:DR患者小动脉闭塞,血流速度下降,舒张期血管阻力增高,使血流减少。CDI检测对DR早期诊断及发病机制研究有重要临床意义。 相似文献
4.
目的探讨发生2型糖尿病视网膜病变(DR)的相关危险因素。方法将200例2型糖尿病(DM)患者分为非糖尿病视网膜病变(NDR)组、单纯型糖尿病视网膜病变(NPDR)组和增殖型糖尿病视网膜病变(PDR)组,分别就其可能诱发DR的危险因素进行病例对照研究。结果NPDR组及PDR组的病程、血压、空腹血糖、糖化血红蛋白、尿微量白蛋白均高于NDR组(P〈0.01),各组年龄、体重指数、胆固醇、甘油三酯无明显差异(P〉0.05)。结论DR的发生与糖尿病病程、尿微量白蛋白、空腹血糖、糖化血红蛋白增高有关,高血压对DR的发生起着促进作用。预防上述危险因素,可减少DR的发生、发展。 相似文献
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目的探讨血小板平均体积(MPV)和视网膜厚度(RT)两项指标在糖尿病性视网膜病变(DR)中的临床意义,并分析MPV与RT在糖尿病各期的相关性,为早期诊断黄斑水肿、判断DR严重程度提供临床诊断依据。方法选取确诊为2型糖尿病(DM)患者80例(159眼),其中男42例(84眼),女38例(75眼),将DM患者分为糖尿病无视网膜病变组(NDR)、非增殖性视网膜病变组(NPDR)和增殖性视网膜病变组(PDR),检测DR患者不同分期的MPV,观察糖尿病黄斑水肿在光学相干断层扫描(OCT)中的形态,定量测定黄斑区RT,并与30例健康成年人(对照组)比较。结果4组MPV比较差异有统计学意义(P<0.01);NPDR组和PDR组与对照组比较差异有统计学意义(P<0.01);NDR组与NPDR组比较差异有统计学意义(P<0.05);NDR及NPDR组与PDR组比较差异均有统计学意义(P<0.05)。黄斑区以中心凹1mm为直径RT对照组为(243.35±11.76)滋m、NDR组(249.95±10.81)滋m、NPDR组(279.50±34.67)滋m、PDR组(305.12±66.01)滋m。4组A1~A9的RT比较,NPDR、PDR组与对照组差异有统计学意义(P<0.05),NDR组与NPDR、PDR组及NPDR与PDR组比较差异均有统计学意义(均P<0.05)。NDR、NPDR和PDR组的MPV与黄斑区中心凹的RT均呈正相关(r=0.54、0.72、0.85,均P=0.00)。对照组的MPV与黄斑区中心凹的RT不相关(r=0.27,P=0.14)。结论MPV增大是DM患者发生DR的危险因素;黄斑区RT与DR严重程度有关,DR程度越重,RT增大的概率就越大,RT大小与是否发生DME相关;DR患者MPV和RT呈正相关,且随着DR分级的加重,相关度越来越高。 相似文献
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目的 观察糖尿病视网膜病变(diabetic retinopathy,DR)行全视网膜激光光凝术后视网膜中央动脉(central retinal artery,CRA)的血流动力学改变情况.方法 应用彩色多普勒成像(color doppler imaging,CDI)检测152例增殖期DR激光光凝术后患者的CRA收缩期血流峰值速度(peak systolic velocity,PSV)、舒张末期血流速度(end diastolic velocity,EDV)、阻力指数(resistance index,RI)及视网膜中央静脉(central retinal vein,CRV)的最大血流速度(maximum blood flow velocity,Vmax)、最低血流速度(minimum blood flow velocity,Vmin),并作对比分析.结果 CRA的PSV、EDV在全视网膜激光光凝术后有所增加,RI降低;CRV的Vmax、Vmin均有所降低,且与光凝术前比较差异无统计学意义(P>0.05),而光凝组术后与对照组1个月后比较差异有统计学意义(P<0.05).结论 全视网膜激光光凝术是治疗增殖期DR的一种安全有效方法,光凝术后血液循环障碍依然存在;应用CDI测定光凝术后患者CRA的血流动力学改变具有一定的临床价值,可为DR的诊断和治疗提供依据. 相似文献
7.
熊淑敏刘志兴陈莉 《南昌大学学报(医学版)》2020,60(1):31
目的探讨彩色多普勒血流成像(CDFI)检测视网膜静脉阻塞(RVO)及抗-VEGF治疗前后眼动脉(OA)、睫状后短动脉(PCA)、视网膜中央动脉(CRA)、视网膜中央静脉(CRV)和颈内动脉(ICA)血流动力学变化及特点。方法用彩色多普勒超声诊断仪检测RVO患者患侧50只眼(均为单眼发病,RVO组)、对侧临床健眼50只眼(健侧组)及同期健康体检者50只眼(对照组)各血管的收缩期峰值流速(PSV)、舒张末期流速(EDV)、CRV的最大血流速度(Vmax),并计算阻力指数(RI)。结果与对照组比较:RVO组OA、PCA、CRA、ICA的PSV和EDV明显降低,RI增大,CRV Vmax降低(P<0.05);健侧组OA、PCA、CRA、ICA的PSV和EDV降低,ICA的RI增大(P<0.05)。与健侧组比较:RVO组CRV Vmax明显降低(P<0.05)。与治疗前比较:25例RVO合并黄斑水肿(RVO-ME)患眼抗-VEGF治疗1周后,血流动力学无明显变化,治疗1个月后CRA的PSV和EDV明显升高,RI降低,CRV Vmax增大(P<0.05)。结论 RVO患眼和对侧临床健眼血流动力学明显异常,抗-VEGF治疗可明显改善RVO患者患眼血流动力学,CDFI技术在RVO的发病机制、临床诊断及治疗效果评价中有重要意义。 相似文献
8.
目的:应用彩色多普勒成像技术对比观察早期糖尿病视网膜病变(DR)病人和健康对照组球后血管血流动力学的差异。方法:我们采用彩色多普勒成像技术,分别测量病人的眼动脉(OA),睫状后短动脉(PCA),视网膜中央动脉(CRA)和静脉(CRV)的收缩期峰值流速(PSV),舒张末期流速(EDV)和平均流速(MV),然后计算每个血管的阻力指数(RI)和搏动指数(PI)。测量比较无糖尿病视网膜病变(NDR)组,非增殖糖尿病视网膜病变(NPDR)组和年龄、性别匹配的健康对照组(HC)组的测量结果,进行分析统计,统计显著性定为P<0.05。结果:在本研究中,观察了75位2型糖尿病病人(包括NDR组49人,NPDR组26人)和20位HC组。与HC组比较,NPDR组OA的EDV(9.00±1.79 VS.6.48±2.35 cm/s)和MV(16.56±3.71 VS.13.93±4.07 cm/s)显著降低(P<0.05),RI值(0.79±0.06 VS.0.72±0.05 cm/s)和PI值(1.80±0.41 VS.1.52±0.39 cm/s)显著增加(P<0.05);NDR组(1.16±0.31 VS.0.96±0.19 cm/s)和NPDR组(1.18±0.38 VS.0.96±0.19 cm/s)的PCA的PI值均显著增加(P<0.05);NDR组CRA的RI和PI值分别为(0.63±0.08 VS.0.60±0.06 cm/s和1.15±0.29VS.0.95±0.17)和NPDR组分别为(0.64±0.08 VS.0.60±0.06 cm/s和1.19±0.32 VS.0.95±0.17 cm/s),均显著增加(P<0.05);NPDR组的CRV的V min值显著增加(3.97±0.98 VS.3.17±0.64 cm/s)(P<0.05)。结论:本研究发现,与健康对照组相比,2型糖尿病病人球后血流参数发生显著的变化,特别是早期DR病人。这些结果表明,眼部血管循环功能异常存在于早期或者前期DR病人中,这些变化可以通过彩色多普勒成像测定。 相似文献
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目的:本研究主要探讨Graves眼病(GO)眼血流参数变化。方法:采用彩色多普勒显像技术检测40例(80只眼)正常人和38例(51只眼)甲亢患者以及22例(36只眼)GO患者眼动脉(OA)、视网膜中央动脉(CRA)的收缩期峰值速度(PSV)、舒张末期血流速度(EDV)和视网膜中央静脉(CRV)的最大流速(Vmax)和最小流速(Vmin)。结果:GO组和OA、CRA的PSV、EDV、TAMX均高于正常对照组(P〈0.001)和甲亢组(P〈0.001),CRV的Vmax、Vmin亦高于正常对照组(P〈0.001)和甲亢组(P〈0.05)。而正常对照组和甲亢组之间眼血流速度无显著性差异(P〉0.05)。3组间OA、CRA的RI无显著性差异(P〉0.05)。结论:①彩色多普勒血流成像技术能够理想显示GO眼血流灌注状况。②轻、中度GO的OA、CRA、CRV流速增快可能继发于眶内炎症。 相似文献
10.
目的:观察2型糖尿病(T2DM)患者红细胞变形能力及细胞因子中肿瘤坏死因子-α(TNF-α)、血管细胞粘附分子(sVCAM-1)、内皮细胞生长因子(VEGF)在T2DM视网膜病变(DR)患者中的变化,探讨它在DR发病中的作用及临床意义。方法:选取85例T2DM患者和30例健康查体者,采用RIA法测定血清TNF-α浓度、采用ELISA法测定血清sVCAM-1、血浆VEGF水平,同时测定血液流变学指标,并分析各变量之间的相关性。结果:①T2DM各组血清TNF-α水平显著高于正常对照组(P均〈0.01),且与餐后2h血糖(P2hBG)、糖化血红蛋白(HbAlc)、sVCAM-1呈正相关;②T2DM组红细胞变形能力明显低于正常对照组(P均〈0.01),各组间亦有显著差异;③T2DM各组血清sVCAM-1水平显著高于正常对照组(P均〈0.01),增殖型视网膜病变(PDR)组水平最高,与非增殖型视网膜病变(NPDR)组未见差异,但NPDR组高于非糖尿病视网膜病变(NDR)组(P〈0.05);④PDR组血清VEGF水平显著高于正常对照组(P〈0.05),NDR及NPDR组与正常对照组无统计学差异(P〉0.05)。结论:T2DM血清TNF-α、sVCAM-1及红细胞变形能力的测定可作为早期预测DR和病情分析的指标:而VEGF可能主要在PDR期发挥促进新生血管形成的作用,对早期检测DR意义不大。 相似文献
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Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD. 相似文献
12.
Jiageng Zhu Jun Li Ruipeng Ji Jianghao Su Mingshun Shen Zhigang Cao 《南京医科大学学报(自然科学版)》2007,21(2):125-128
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment. 相似文献
13.
Tao Ye * Zhi-quan Liu Jian-jun Mu Xi-han Fu Jun Yang Bao-lin Gao and Xiao-hong Zhang Department of Cardiology First Hospital of Xi'an Jiaotong University Xi'an Hanzhong Cardiovascular Institute Hanzhong 《中国医学科学杂志(英文版)》2004,19(4):248-251
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure. 相似文献
14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险. 相似文献
15.
Jingming Zhu Ningning Hui Xiuhong Jiang Huaxing Zhang Chengzhang Fu 《南京医科大学学报(自然科学版)》2007,21(6):386-389
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients. 相似文献
16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption. 相似文献
17.
The clinicopathological and immuohistochemical analysis of solid-pseudopapillary tumor of the pancreas: report of 9 cases 总被引:1,自引:0,他引:1
Shaoqin Chen Shengquan Zou Qibao Dai Peisheng Huang Weihua Cai Hong Li 《南京医科大学学报(自然科学版)》2007,21(6):398-401
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype. 相似文献
18.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P. 相似文献
19.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine. 相似文献
20.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center. 相似文献