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101.
Skin reactions to irritants assessed by non-invasive bioengineering methods   总被引:3,自引:1,他引:2  
Pathophysiological components of irritant contact dermatitis caused by 3 chemically-different irritants were investigated. 20 healthy volunteers were patch tested with sodium lauryl sulphate, nonanoic acid and hydrochloric acid on the flexor side of the upper arm. The skin response was evaluated after 24, 48 and 96 h by visual scoring and measured by the following bioengineering methods: transepidermal water loss measurement, electrical conductance for measurement of skin hydration, laser Doppler flowmetry for measurement of cutaneous blood flow and 20 MHz ultrasound A-scan for measurement of skin thickness. In spite of homogeneous inflammatory responses, significant differences in the severity of the injury to the skin barrier function caused by the different irritants were found. Also significant differences between irritants were found in the time course of development of maximum irritant reactions. Bioengineering methods indicating inflammatory responses (measurement of blood flow and skin thickness) were helpful in quantifying the irritant response in general, while bioengineering methods indicating epidermal damage (measurement of TEWL and electrical conductance) were helpful in classifying the individual irritants.  相似文献   
102.
经阴道彩色多普勒诊断未破裂型输卵管妊娠   总被引:1,自引:1,他引:0  
本文介绍经阴道彩色多普勒诊断未破裂型输卵管妊娠26例,13例经手术及病理检查证实,13例经临床确诊,符合25例,诊断符合率96.15%;误诊1例,误诊率3.85%。经阴道彩色多普勒检查其二维图像清晰,彩色血流灵敏,能更早发现输卵管妊娠包块内特异的滋养层周围血流及同侧卵巢的黄体血流,使输卵管妊娠在破裂前就能作出诊断,具有较高的临床应用价值。  相似文献   
103.
The effect of spinal cord stimulation (SCS) on cerebral blood flow (CBF) has, in the past, been evaluated by semiquantitative techniques, but has not been used to treat CBF diseases. The aim of this study was to assess the effect of cervical SCS on regional blood flow by both semiquantitative and quantitative methods. Thirty‐five patients with cervical SCS‐implanted devices were enrolled. The following parameters were measured before and after cervical SCS: systolic and diastolic velocity (cm/s) in the middle cerebral artery (MCA) by transcranial Doppler (TCD) and volume blood flow quantification (ml/min) in the common carotid artery (CCA) by color Doppler. During cervical SCS there was a significant and bilateral increase in systolic (21%) and diastolic (26%) velocity in the MCA and in CCA blood flow (50%). We conclude that cervical SCS increases blood flow in the middle cerebral artery and common carotid artery. The consistent increase supports the potential usefulness of cervical SCS as an adjuvant treatment for cerebral blood flow diseases.  相似文献   
104.
目的:探讨彩超检测高血脂患者颈动脉内膜-中膜厚度及斑块形成的意义,方法:medison-8000Ex高频超声对120例高血脂患者及120例血脂正常者两组,观察其动脉的内膜-中膜厚度及斑块形成情况。结果:血脂升高组,颈总动脉最大内膜-中膜厚度及粥样斑块发生率明显增高。结论:彩超可清晰显示颈动脉内膜-中膜情况,对高血脂引起的动脉粥样硬化检出预报和疗效观察有重要临床意义。  相似文献   
105.
[目的]研究 2型糖尿病患者的血管内皮依赖性舒张功能.[方法]采用高分辨率超声,测定 21例正常人和 31例 2型糖尿病患者的肱动脉反应性充血后,以及含服硝酸甘油后的血管内经和血流量的变化.[结果]两组间空腹血糖、餐后 2 h血糖差异有统计学意义( P < 0.01),而性别、年龄、甘油三酯、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇、收缩压、舒张压、体质量指数差异均无统计学意义( P >0.05).2型糖尿病组反应性充血后血管内径变化率 [( 9.0± 4.9)% vs (15.5± 3.0)% , (P< 0.01)],含服硝酸甘油后血管内径变化率 [( 17.3± 8.4)% vs (23.3%± 3.5)% , ( P< 0.01)],含服硝酸甘油后血流量 [( 126.1± 48.2) mL/min vs (157.8 ± 52.6) mL/min (P< 0.05)]较正常对照组显著性降低.[结论] 2型糖尿病患者不仅存在血管内皮依赖性舒张功能障碍,而且还存在非血管内皮依赖性舒张功能障碍.  相似文献   
106.
BACKGROUND: Intravenous tissue plasminogen activator (TPA) therapy can be monitored with 2 MHz transcranial Doppler (TCD). This article describes the design of CLOTBUST (combined lysis of thrombus in brain ischemia using transcranial ultrasound and systemic TPA), the first prospective international multicenter randomized clinical trial of noninvasive externally applied ultrasound to enhance systemic thrombolysis in human stroke. SUBJECTS: Patients with acute ischemic stroke eligible for intravenous TPA therapy within 3 hours of symptom onset who have detectable middle cerebral artery occlusion on a prebolus TCD are included in this trial. All patients receive standard 0.9 mg/kg TPA therapy. Patients are randomized (1:1) to either 2 hours of continuous monitoring with TCD or placebo monitoring. FDA-approved portable diagnostic TCD equipment and standard headframes (Marc series, Spencer Technologies, Seattle, WA) are used. Output of TCD units is set at 100% power achievable at depths of insonation that display the worst TIBI flow grade signals. METHODS AND END-POINTS: Acute MCA occlusion on prebolus TCD is defined as thrombolysis in brain ischemia (TIBI) flow grades 0-3. Treating physicians are blinded to randomization assignment, and certified scorers measure stroke severity using the National Institute of Health Stroke Scale (NIHSS). Safety of continuous TCD monitoring is determined by rates of symptomatic (NIHSS score increase by 4+ points) intracerebral hemorrhage within 72 hours after initial symptom onset. Potential enhancement of TPA therapy will be determined using combined primary end-point of early complete recanalization on TCD (TIBI flow grades 4-5), dramatic recovery (NIHSS < or = 3 points), or decline in the NIHSS > or = 10 points repeatedly measured every 30 minutes within 2 hours after TPA bolus. Other end-points include recovery at 24 hours and 3 months, modified Rankin scores (mRS) are obtained at 90 days, and favorable outcome is determined as NIHSS or mRS scores 0-1. CONCLUSIONS: The aim of phase II CLOTBUST trial is to determine the rates of early complete recanalization and dramatic/early clinical recovery in TPA + TCD and TPA groups. The sample size is set at 126 patients since a medium effect size (.50) is anticipated for TPA + TCD group vs TPA alone to achieve combined primary end-point.  相似文献   
107.
经阴道超声诊断子宫内膜癌   总被引:1,自引:0,他引:1  
目的 探讨应用经阴道超声(TVS)诊断绝经前后出血妇女子宫内膜癌的价值。方法 采用彩色多普勒超声诊断仪检测74例阴道异常出血的妇女,其中绝经前28例,绝经后46例,所有患者均取子宫内膜组织行病理对照。结果 TVS检测子宫内膜癌的敏感性、特异性、假阳性率、假阴性率、阳性预测值和阴性预测值,绝经前妇女依次为61.5%,50.0%,14.3%,23.8%,94.1%和54.5%,绝经后妇女依次为97.3%,55.6%,44.4%,2.7%,90.0%和83.0%。结论 TVS检测可作为子宫内膜癌首选的筛查方法,尤其对于绝经后妇女价值更大。  相似文献   
108.
目的探讨多巴酚丁胺负荷超声心动图(DSE)和组织多普勒成像技术(TDI)在冠心病(CHD)诊断中的应用价值,以寻求一种敏感的、无创的CHD诊断方法。方法选择胸闷或胸痛怀疑CHD患者40例,应用TDI测量静息状态(Rest)下前壁中段收缩峰值速度(Vs),以及多巴酚丁胺峰值负荷状态(Peak)下前壁中段Vs,同时测量静息心率和负荷心率;所有入选对象均进行冠脉造影,并根据左前降支狭窄程度是否大于等于50%分为左前降支狭窄组(LST组)与左前降支非狭窄组(non-LST组)。分别比较Rest和Peak前壁中段LST组与non-LST组平均Vs差别等。结果Rest前壁中段LST组与non-LST组Vs差别无显著性意义;但Peak前壁中段LST组与non-LST组差别有显著性意义。结论DSE结合TDI是诊断冠心病有价值的定量分析方法。DSE在诊断CHD时的敏感性、准确性明显优于静息状态超声心动图。  相似文献   
109.
目的对二氧化碳吸入、屏气及过度换气等3种不同的脑血管反应性检测方法进行比较,拟为临床应用探索一种有效且简便的方法。方法70例健康体格检查者通过经颅多普勒(TCD)超声技术常规检测颅底及颈部各动脉,然后分别进行二氧化碳吸入试验、过度换气试验和屏气试验,记录试验前后双侧大脑中动脉血流速度变化数据和趋势,检测脑血管反应性。结果吸入二氧化碳后,大脑中动脉平均血流速度明显加快,增加率为(44.86±10.18)%;过度换气时,平均血流速度明显减慢,于过度换气20~30s后降至平台期,平均下降率为(33.63±8.62)%,直至过度通气结束血流速度无明显变化。70例受试者平均屏气时间为(41.66±9.51)s,其中男性屏气时间(42.05±9.23)s,女性(40.63±10.47)s,男女之间差异无统计学意义(P>0.05);屏气后大脑中动脉平均血流速度明显加快,增加率为(46.53±11.83)%;平均屏气指数为1.16±0.37;屏气后血流速度增加率和屏气指数之间呈高度正相关(r=0.865,P<0.01);当屏气时间>30s时,无论采用屏气后血流速度增加率或屏气指数作为分析指标,均可准确地反映脑血管反应性变化。对二氧化碳吸入试验、过度换气试验及屏气试验3种不同方法进行比较显示,过度换气试验与二氧化碳吸入试验、屏气试验间差异有统计学意义(P<0.01);而二氧化碳吸入试验与屏气试验之间差异无统计学意义(P>0.05)。结论二氧化碳吸入试验、屏气试验和过度换气试验均可有效地评价脑血管反应性,其中以屏气试验评价脑血管反应性更为简便。  相似文献   
110.
The present trial was designed to evaluate clinical scores (single observer) of sodium lauryl sulphate (SLS)-induced skin irritation in a group of subjects (n = 10) over a 10-day period along with various skin function parameters. In order to avoid significant variations due to secondary phenomena, the following parameters were recorded with non-invasive instruments in this order: skin capacitance (C1; arbitrary units; CM420 Corneometer), transepidermal water loss (TEWL; g/m2.h; Evaporimeter) and laser Doppler flowmetry (CBFV: cutaneous blood flow values; Periflux). All examinations were performed during winter on reclined relaxed subjects present for at least 10 min in a test room with controlled temperature and relative humidity (t degrees: 19.5-20.7 degrees C and RH: 47.3-60.3%). The analysis of differential data (delta = value at tx-value before test; 2-way ANOVA) was made on single parameters as a function of site (volar forearm versus neck) and time (from 24 h after 48-h occlusion with 5% SLS up to 10 days later). The profile of erythema scores over time differed between neck and forearm, but the delta CBFV readings with the laser Doppler instrument did not detect significant site-time interactions. Roughness (blind evaluation with palpating finger) and capacitance readings (delta C1) showed significant differences between sites, but the profile over time was similar in both locations. delta TEWL did not differ according to anatomical location. The reason for different erythema scores on neck and forearm might be related to inherent regional variation of optical properties of the skin or to a substantial contribution of SLS-induced roughness to the readings of erythema.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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