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991.
PURPOSE: To determine whether spectral Doppler measurements obtained from bilateral uterine, arcuate, radial, and spiral arteries in early gestation correlate with adverse pregnancy outcome. METHODS: One hundred five pregnant women underwent transvaginal Doppler sonographic examination of uteroplacental circulation at 6-12 weeks' gestation. Resistance index (RI) and pulsatility index (PI) of bilateral uterine, arcuate, radial, and spiral arteries were measured. Diameters of gestational sac (GS) and yolk sac, crown-rump length (CRL), GS-CRL difference, and GS/CRL ratio were also recorded. Correlation was made with pregnancy outcome. RESULTS: Sixteen women developed adverse pregnancy outcome. In these women, right uterine artery PI and RI were significantly higher than in women with normal obstetrical outcome. Spiral artery PI and RI values were also higher, but the difference was not statistically significant. GS-CRL difference, GS/CRL ratio, and yolk sac diameters were significantly lower in this group. CONCLUSION: Transvaginal Doppler examination can detect hemodynamic changes in uteroplacental circulation associated with subsequent adverse pregnancy outcome. 相似文献
992.
993.
目的:探讨多种方法联合评价胎儿脐动脉多普勒信号的临床价值。方法:将71例妊娠20-41周的妇女分为正常组(56例)和病理妊娠组(15例)。用彩色多普勒超声测得胎儿脐动脉多普勒信号,将此信号以音频形式输入计算机,分别以零极点模型、Teagar能量法和分形方法进行信号分析,同时常规计算脐动脉收缩期最大血流速度(S)与舒张期末血流速度(D)的比值(S/D)。以多元决策法综合上述4种方法的特征参数评价脐动脉多普勒信号。结果:对病理妊娠组,利用常规S/D法、零极点模型法、Teagar能量法、分形法的异常率分别为26.67%、66.67%、53.33%和46.67%。利用多元决策法,病理妊娠组异常率为80.00%,与前4种方法相比差异有显著性意义(P<0.05)。结论:利用多元决策法分析脐动脉血流信号能敏感、客观、准确地反映病理状态下的脐血流改变。 相似文献
994.
T. Kangro T. Jonason E. Henriksen I. Ringqvist 《Clinical physiology and functional imaging》1997,17(6):579-590
Doppler indices of left ventricular diastolic filling are associated with various cardiac and extracardiac factors. Afterload is one of the extracardiac factors influencing left ventricular diastolic filling. The distensibility of the great arteries is one of the components of afterload. In this study, the relation between Doppler indices of left ventricular filling and the distensibility of the common carotid arteries was investigated. We studied 237 subjects at 50 years of age with Doppler echocardiography and ultrasound examination of the common carotid arteries. The following Doppler indices of left ventricular filling were studied: peak early diastolic velocity E-wave, peak atrial diastolic velocity A-wave and early to atrial peak velocity ratio, E/A. Carotid arterial characteristics were: distensibility coefficient, carotid arterial diameter change in systole and fractional change in the carotid arterial diameter. The relation between Doppler indices of left ventricular filling and carotid arterial characteristics was assessed by univariate and multivariate regression analysis. There was a significant univariate, positive association between E/A ratio and carotid arterial distensibility (r = 0·27, P<0·001), carotid arterial systolic diameter change (r = 0·19, P<0·005) and fractional change of the carotid arterial diameter (r = 0·20, P<0·005). In multivariate analysis, E/A ratio was independently associated with carotid arterial distensibility (P<0·005), after adjusting for heart rate, body mass index and gender. Decreased carotid arterial distensibility was associated with a reduction in E/A ratio, suggesting that arterial distensibility may have an effect on left ventricular diastolic filling or that changes in the arterial elastic properties are associated with corresponding structural changes in the left ventricle. 相似文献
995.
Akihito Nakai Hiroko Yamada Atsuko Oya Tatsuo Koshino Tsutomu Araki 《Journal of Medical Ultrasonics》2002,29(4):189-194
Purpose To compare global cerebral blood supply in healthy pregnant women and nonpregnant women.
Materials and Methods Flow volumes in the common, internal, and external carotid, arteries and the vertebral arteries were determined using color
Doppler ultrasonography in 17 nonpregnant women, 55 healthy pregnant women at 10 to 40 weeks gestation, and 24 puerperal women
within 1 week after spontaneous delivery. Global cerebral blood flow was defined as the sum of flow volumes in the bilateral
internal carotid and vertebral arteries.
Results In the nonpregnant group, mean flow volumes of the common, internal, and external carotid arteries and the vertebral arteries,
and mean global cerebral blood flow volume were (mean±SD) 863±108 ml/min, 554 ±94 ml/min, 386±65 ml/min, 115±24 ml/min, and
669±104 ml/min, respectively. During the second trimester, flow volumes of the common and external carotid arteries increased
significantly in the healthy pregnant women, to about 130 percent and 140 percent of the nonpregnant level, respectively.
Global cerebral blood flow volume remained unchanged during pregnancy.
Conclusion During pregnancy, increase in flow volumes in the common carotid arteries were accompanied by elevated flow volumes of the
external carotid arteries but not the internal carotid arteries. This distribution would tend to regulate the volume of global
cerebral blood flow throughout the period of pregnancy. 相似文献
996.
Lianshan Piao Yasushi Tanaka Takashi Nomiyama Kunihiro Nakajima Takeshi Ogihara Shinnya Miwa Takao Urabe Hirotaka Watada Ryuzo Kawamori 《Current therapeutic research》2002,63(12):842-852
Background: We previously reported that the carotid artery intima-media thickness (IMT) increased with age and that patients with type 2 diabetes mellitus (DM) had a significantly larger IMT than did age-matched nondiabetic subjects with normal glucose tolerance. Although the exact mechanism behind the increase in IMT in diabetic patients has not been determined, data obtained from in vivo and in vitro studies suggest that hyperglycemia-induced oxidative stress may lead to atherogenesis.Objective: The aim of this single-center study was to determine whether long-term oxidative stress and the carotid IMT are influenced by differences of the angiotensin-converting enzyme insertion/deletion (ACE I/D) and NADPH (nicotinamide adenine dinucleotide phosphate, reduced form) oxidase p22phox C242T genotypes.Methods: Eligible subjects were Japanese patients with type 2 DM. Polymorphism of the ACE I/D and p22phox gene was investigated using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism, respectively. The rate of an acquired mutation of mitochondrial DNA—that is, A-to-G substitution at position 3243 (mtDNA A3243G)—was determined by real-time PCR. As a marker of early atherosclerosis, the carotid artery IMT was measured using high-resolution B-mode ultrasonography.Results: A total of 262 Japanese patients (173 men, 89 women; mean [SEM] age, 58 [0.6] years [range, 18-80 years]) were recruited and enrolled for study. An ACED-positive (DD or DI) and p22phox 242T-negative genotype (CC) was associated with a significantly higher mtDNA A3243G mutation rate than the other 3 possible genotypes (0.0219% [0.0028%] vs 0.0097% [0.0012%]; P < 0.05). This genotype also had higher maximum and mean IMT values than the other genotypes (1.13 [0.048] mm vs 0.99 [0.03] mm and 1.01 [0.036] mm vs 0.92 [0.023] mm; P < 0.05). These parameters were similar among the other 3 genotypes.Conclusion: In this study, the ACED-positive and p22phox 242T-negative genotype showed higher rates of somatic mtDNA mutation (mtDNA A3243G) and higher carotid mean and maximum IMT levels. 相似文献
997.
目的探讨老年颅外段颈动脉狭窄患者经皮血管内支架置入血管成形治疗及围手术期护理等相关问题。方法21例老年颅外段颈动脉狭窄患者经全脑数字减影血管造影(DSA)检查诊断后,均采用经股动脉入路应用自膨式支架行经皮血管内支架置入血管内成形术治疗。结果21例(次)支架置放均获成功。DSA显示狭窄段的颈动脉直径明显扩大。仅1例出现部分运动性失语。随访2~24个月,全部患者均未再发生脑缺血,其中2例行DSA复查,6例行多普勒超声复查,均无再狭窄发生。结论经皮血管内支架置入血管成形术治疗老年颅外段颈动脉狭窄安全性高,效果可靠,围手术期护理是手术成功的保障。 相似文献
998.
Khanna D Sinha A Nanda NC Gupta R Sidhu M Vengala S Dod HS Ilgenli TF 《Echocardiography (Mount Kisco, N.Y.)》2004,21(4):349-353
In the current study, we describe an adult patient with torrential aortic regurgitation due to an aortic dissection flap interfering with aortic cusp motion, in whom a transesophageal echocardiogram with the probe positioned in the upper esophagus and transpharyngeal ultrasound examination demonstrated prominent reversed flow throughout diastole in the left subclavian, left vertebral, left common carotid, and left internal carotid arteries. Another unique finding was the demonstration of aortic valve leaflets held in the fully opened position in diastole by the dissection flap as it prolapsed into the left ventricular outflow tract, dramatically documenting the mechanism of torrential aortic regurgitation in this patient. 相似文献
999.
颈动脉粥样硬化与血管性认知障碍相关性研究 总被引:1,自引:0,他引:1
目的 探讨颈动脉粥样硬化与血管性认知障碍的关系。方法 选取2005年5月至2007年4月我院军职干部科疗养干部58例,所有研究对象均进行神经心理检查和颈动脉超声检查,根据颈动脉内膜-中层厚度(IMT)值,将研究对象分为3组:IMT〈1.0mm组、IMT 1.0~1.2mm组和IMT〉1.2mm组,并对不同组的神经心理检查结果进行分析。结果 不同颈动脉粥样硬化患者日常生活能力比较无显著性差异(P〉0.05)。简易智能状态检查量表总分各组间比较无显著性差异。地点定向、时间定向、计算能力、短程记忆、言语复述、语言表达、书写能力、结构能力评分,IMT〉1.2mm组得分明显较低,3组间比较有显著性差异(P均〈0.05)。结论 颈动脉粥样硬化与血管性认知障碍存在密切的关系。 相似文献
1000.
Pauline H. Croll Daniel Bos Meike W. Vernooij Banafsheh Arshi Frank R. Lin Robert J. Baatenburg de Jong M. Arfan Ikram André Goedegebure Maryam Kavousi 《Journal of the American Medical Directors Association》2019,20(12):1617-1622.e1
ObjectivesCardiovascular disease may be linked to hearing loss through narrowing of the nutrient arteries of the cochlea, but large-scale population-based evidence for this association remains scarce. We investigated the association of carotid atherosclerosis as a marker of generalized cardiovascular disease with hearing loss in a population-based cohort.DesignCross-sectional.SettingA population-based cohort study.Participants3724 participants [mean age: 65.5 years, standard deviation (SD): 7.5, 55.4% female].MethodsUltrasound and pure-tone audiograms to assess carotid atherosclerosis and hearing loss.ResultsWe investigated associations of carotid plaque burden and carotid intima-media thickness (IMT) (overall and side-specific carotid atherosclerosis) with hearing loss (in the best hearing ear and side-specific hearing loss) using multivariable linear and ordinal regression models. We found that higher maximum IMT was related to poorer hearing in the best hearing ear [difference in decibel hearing level per 1-mm increase in IMT: 2.09 dB, 95% confidence interval (CI): 0.08, 4.10]. Additionally, third and fourth quartile plaque burden as compared to first quartile was related to poorer hearing in the best hearing ear (difference: 1.06 dB, 95% CI: 0.04, 2.08; and difference: 1.55 dB, 95% CI: 0.49, 2.60, respectively). Larger IMT (difference: 2.97 dB, 95% CI: 0.79, 5.14), third quartile plaque burden compared to first quartile (difference: 1.24 dB, 95% CI: 0.14, 2.35), and fourth plaque quartile compared to first quartile (difference: 2.12 dB, 95% CI: 0.98, 3.26) in the right carotid were associated with poorer hearing in the right ear.Conclusions and ImplicationsCarotid atherosclerosis is associated with poorer hearing in older adults, almost exclusively with poorer hearing in the right ear. Based on our results, it seems that current therapies for the prevention of cardiovascular disease may also prove beneficial for hearing loss in older adults by promoting and maintaining inner ear health. 相似文献