彩色多普勒超声诊断糖尿病下肢动脉病变的临床价值

目的 :研究彩色多普勒超声在糖尿病下肢动脉病变诊断中的应用。方法 :对临床上诊断为非胰岛素依赖型糖尿病 (NIDDM)患者发生下肢动脉病变的 6 2例进行彩色多普勒超声检查 ,并以 2 0例无糖尿病正常人作对照。结果 :6 2例NIDDM患者中阳性结果 4 0例 ,发病率 6 4 .5 2 %。正常对照组 2 0例 ,阳性结果 4例 ,发病率2 0 % ,下肢动脉病变程度与NIDDM组有显著性差异P <0 .0 1。结论 :彩色多普勒超声诊断糖尿病下肢动脉病变具有重要临床意义 ,且下肢动脉病变与NIDDM有密切相关性。     

Effects of Natural Brown Cotton Bleached Gauze on Wound Healing

Natural brown cotton has favorable antibacterial and antioxidant properties. In this study, we explored the effect of gauze made from natural brown cotton after scouring and bleaching on wound healing in rats. In this work, a control experiment was adopted. The control group used absorbent cotton gauze, and the experimental group utilized natural brown cotton bleached gauze. The materials were applied to rat models to explore the effects of the two dressings on wound healing. By analyzing the wound healing state of rats, calculating the healing rate, and combining the pathological HE staining, Masson staining, and CD31 immunohistochemical staining, the results showed that both gauzes have positive effects on the wound healing of the rats. Moreover, compared with the control group, the wound healing rate of rats in the experimental group increased by 14.81%, the number of inflammatory cells decreased by 12.93%, the number of new blood vessels increased by 6.88%, the growth rate of the granulation tissue area was 10.76%, the step-up rate of the area occupied by collagen was 33.71%, and the increase rate of optical density value was 10.00%. This study found that natural brown cotton bleached gauze has a better effect on wound healing than ordinary absorbent cotton gauze, and can be used as medical dressings.     

细胞标记用大粒径羧化彩色高分子微球的研制

制备一种普通光学显微镜下可见的细胞标记用大粒径彩色高分子微球。以苯乙烯及丙烯酰胺为原料，在体系中加入电解质，有机溶剂及油溶性染料，采用无乳化剂乳液聚合法制备彩色高分子微球，并通过酰肼化和羧化两步反应在微球表现衍生出羧基。     

SBS改性浅色沥青胶结料的流变性能

采用苯乙烯-丁二烯-苯乙烯嵌段共聚物（SBS）和乙烯-醋酸乙烯共聚物（EVA）复合改性C9树脂和高含量芳烃减压馏分油获得了浅色沥青胶结料,对比考察了国内外同类产品和70#基质沥青族组成和流变性能。研究结果表明：EVA和SBS可明显改善浅色沥青胶结料的针入度、软化点和延度;添加SBS后浅色沥青胶结料的动力黏度变大,损耗因子的变化幅度变小,温度敏感性能有较大改善。动态剪切和应力流变测试结果表明,加入SBS后浅色沥青胶结料复合模量略有改善,损耗因子在50℃附近出现明显拐点,抗车辙性能有较大改善。蠕变性能分析结果表明,SBS改性浅色沥青胶结料的形变和恢复率可达70#基质沥青水平,胶结料形变恢复率明显提高。     

彩色多普勒超声在下肢深静脉血栓中的诊断价值

目的：探讨彩色多普勒在下肢深静脉血栓（DVT）中的诊断价值。方法：通过彩色多普勒超声对58例DVT患者进行检测,观察血管内径,血栓范围,血栓回声特征及管腔血流情况。结果：急性DVT形成后静脉内径明显增宽,血栓表现为均质低回声;慢性血栓回声为不均质较高回声,血栓部位血流信号消失或充盈缺损,并可继发深静脉瓣功能不全。结论：彩色多普勒超声诊断DVT具有很高的敏感性和特异性,是一种无创伤性检查方法。且操作简便,具有安全、迅速等特点,同时可通过动态观察其演变情况,判断临床治疗效果,故为诊断DVT首选方法。     

Myocardial perfusion imaging using a non-contrast agent MR imaging technique

Introduction: A MR imaging (MRI) method has been developed to determine quantitatively myocardial perfusion (P) in the rat heart in vivo. This method has the potential to non-invasively measure cardiac perfusion without the use of a contrast agent by exploiting the endogenous contrast from flowing blood itself. Method and Results: Principle of the technique is the arterial spin labeling of endogenous water protons within the short axis imaging slice. Arterial spin labeling techniques are based on a model that uses inflow effects to relate intrinsic changes in longitudinal relaxation (T ₁) to tissue perfusion. Perfusion is determined from the difference between a slice selective and a global inversion recovery experiment. Perfusion was determined at rest and during hyperemia induced by intravenous adenosine (3 mg/(kgmin)). The MR perfusion values were compared with perfusion data obtained in the same animal using the colored microspheres (MS) technique as the gold standard. The MR perfusion (mean ± SEM) was 3.3 ± 0.2 ml/min/g at rest and 4.6 ± 0.6 ml/min/g during adenosine. Perfusion values obtained by colored MS were 3.4 ± 0.2 and 4.7 ± 0.8 ml/min/g at rest and during vasodilation, respectively. Adenosine decreased mean arterial pressure (MAP) from 120 to 65 mmHg which implies a reduction of coronary resistance (CR) to about 50% of baseline. Conclusion: Our study shows that quantitative mapping of perfusion may be performed non-invasively by MRI. The MR perfusion data are in excellent correlation with data obtained by the well-established colored MS technique. Determination of perfusion reserve confirms that coronary perfusion is highly dependent on blood pressure due to changes in CR.     

经阴道彩色多普勒超声对异位妊娠的诊断

目的探讨经阴道彩色多普勒超声对异位妊娠的诊断价值。方法对221例经手术病理确诊的异位妊娠,应用经阴道彩色多普勒超声检查,并将检查结果与手术病理结果进行对照分析。结果本组221例异位妊娠病例中,经阴道彩色多普勒超声诊断215例,漏误诊6例,诊断符合率为97.3%,漏误诊率2.7%。结论经阴道彩色多普勒超声对异位妊娠具有重要的诊断价值,可作为异位妊娠的首选诊断方法。     

序贯应用四种不同颜色的非放射性彩色微球测定器官血流量

目的 探讨以4种颜色的非放射性彩色微球(粉、黄、白、紫)序贯测定同一种动物经历4种不同腹腔内压状态时的脏器血流量的可行性及准确性.方法 雄性Wistar大鼠6只,通过腹腔内加压气囊建立0、5、10、15 mm Hg(1 mm Hg =0.133 kPa)等4种腹腔内压状态,分别以IAPx(x=0、5、10、15)表示.每次持续加压10 min,即通过左心室导管注入相应地注入粉色、黄色、白色、紫色中的一色微球.抽取参比血样后立即输注同等量的同种异体血.腹压去除后,间隔15 min.每只大鼠均依次经历4种不同的腹压状态.实验结束,静脉注入饱和氯化钾处死大鼠,并收集组织标本.标本经过碱性组织液消化、超声细胞破碎仪破碎、DMF染料提取及吸光度值测定.依照组织血流量(Qt)[ml／(min·g)]=组织吸光度值(At)×参比血样的血流量(Qb)/参比血样吸光度值(Ab)公式,用以计算脏器血流量.结果 微球于血液内分布均一,4组不同腹腔内压下左、右肾之间血流量差异无统计学意义( F=0.177,P＞0.05),[左肾血流量:(2.02±0.47)、(1.39±0.62)、(0.81±0.24)、(0.22±0.09) ml/( min·g);右肾血流量:(2.23±0.26)、(1.38 ±0.61)、(0.89±0.31)、(0.24±0.09) ml/(min·g)]具有明显相关(P＜0.01,R=0.687).随腹腔内压力的增加,肝脏等腹腔内脏器血流量下降明显[肝动脉血流量:(0.16±0.05)、(0.15 ±0.03)、(0.10±0.03)、(0.02±0.01) ml/(min·g)];门静脉血流量:(1.73±0.41)、(1.19±0.21)、(0.83±0.18)、(0.38 ±0.08)ml/( min·g)].而心、脑等重要脏器血流量在腹腔内压力处于一定范围内(5～10 mm Hg),能够在一定程度上得以维持,当腹腔内压力升至15 mm Hg时,心、脑等脏器血流量亦表现为下降趋势[心脏血流量:(2.56±0.95)、(1.69±0.95)、(1.44±0.41)、(0.71 ±0.24) ml/(min·g);大脑血流量:(0.49±0.09)、(0.22±0.07)、(0.22±0.06)、(0.19±0.02)ml/(min·g).微球回收率为(92.0±7.1)％.结论 非放射性彩色微球能够完成测定4种不同腹压状态下大鼠多脏器血流量改变,是一种准确可行的血流动力学检测方法,可用于研究同一动物经历不同状态后血流动力学的变化,对于小型动物尤为适用.     

Effect of temporal autocorrelation due to physiological noise and stimulus paradigm on voxel-level false-positive rates in fMRI

Statistical mapping within a binary hypothesis testing framework is the most widely used analytical method in functional MRI of the brain. A common assumption in this kind of analysis is that the fMRI time series are independent and identically distributed in time, yet we know that fMRI data can have significant temporal correlation due to low-frequency physiological fluctuation (Weisskoff et al. [1993]; Proc Soc Magn Reson Med 9:7; Biswal et al. [1995]: Mag Reson Med 34:537–541). Furthermore, since the signal-to-noise ratio will vary with imaging rate, we should expect that the degree of correlation will vary with imaging rate. In this paper, we investigate the effect of temporal correlation and experimental paradigm on false-positive rates (type I error rates), using data synthesized through a simple autoregressive plus white-noise model whose parameters were estimated from real data over a range of imaging rates. We demonstrate that actual false-positive rates can be biased far above or below the assumed significance level α when temporal autocorrelation is ignored in a way that depends on both the degree of correlation as well as the paradigm frequency. Furthermore, we present a simple method, based on the noise model described above, for correcting such distortions, and relate this method to the extended general linear model of Worsley and Friston ([1995]: Neuroimage 2:173–181). Hum. Brain Mapping 6:239–249, 1998. © 1998 Wiley-Liss, Inc.     

高频彩色多普勒超声诊断精索静脉曲张的体会

目的探讨高频彩色多普勒超声对精索静脉曲张的诊断价值。方法对2007年2月～2010年6月期间在我院就诊的53例经高频彩色多普勒超声诊断为精索静脉曲张的患者作回顾性分析。结果根据曲张程度不同分三度：Ⅰ度12例,Ⅱ度32例,Ⅲ度9例。左侧精索静脉曲张46例,双侧精索静脉曲张7例。结论高频彩色多普勒超声在判断有否精索静脉曲张及嘶张的程度有着重要的价值,应作为检查精索静脉曲张的首选方法。