• 【平行检测违反颜色恒定性。】 复制标题 收藏 收藏
    DOI:10.1073/pnas.141505198 复制DOI
    作者列表:Foster DH,Nascimento SM,Amano K,Arend L,Linnell KJ,Nieves JL,Plet S,Foster JS
    BACKGROUND & AIMS: :The perceived colors of reflecting surfaces generally remain stable despite changes in the spectrum of the illuminating light. This color constancy can be measured operationally by asking observers to distinguish illuminant changes on a scene from changes in the reflecting properties of the surfaces comprising it. It is shown here that during fast illuminant changes, simultaneous changes in spectral reflectance of one or more surfaces in an array of other surfaces can be readily detected almost independent of the numbers of surfaces, suggesting a preattentive, spatially parallel process. This process, which is perfect over a spatial window delimited by the anatomical fovea, may form an early input to a multistage analysis of surface color, providing the visual system with information about a rapidly changing world in advance of the generation of a more elaborate and stable perceptual representation.
    背景与目标: : 尽管照明光的光谱发生变化,反射表面的感知颜色通常保持稳定。可以通过要求观察者将场景上的照明变化与包含该场景的表面的反射特性的变化区分开来操作地测量这种颜色恒定性。这里显示的是,在快速光源变化期间,几乎可以独立于表面的数量而容易地检测到其他表面阵列中一个或多个表面的光谱反射率的同时变化,这表明这是一种预先注意的,空间平行的过程。此过程在由解剖中央凹界定的空间窗口上是完美的,可以形成对表面颜色的多阶段分析的早期输入,从而在生成更精细的之前为视觉系统提供有关快速变化的世界的信息。和稳定的感知表示。
  • 【选定的问卷大小和颜色组合与邮寄调查回复率显着相关。】 复制标题 收藏 收藏
    DOI:10.1016/j.jclinepi.2007.01.006 复制DOI
    作者列表:Beebe TJ,Stoner SM,Anderson KJ,Williams AR
    BACKGROUND & AIMS: OBJECTIVE:To determine the degree to which mailed survey response rates, response times, and nonresponse bias are affected by questionnaire size and color. STUDY DESIGN AND SETTING:Questionnaires were mailed to a random sample of 2,000 Mayo Clinic patients in one of four size/color "test" groups. One thousand three hundred nine surveys were completed, approximately two-thirds in each group. RESULTS:A small (6 (1/8) x 8 (1/4) in) questionnaire booklet on white paper had a higher response rate (68.4%) than a similarly sized questionnaire on blue paper (62.3%). A large (8 (1/4) x 11 in) questionnaire on white paper had a 62.7% rate, whereas a large, blue questionnaire had a response rate of 68.6%. Median response times did not differ by questionnaire size/color. No evidence of differential nonresponse bias was observed across the four test groups. CONCLUSION:This study supports the use of a small/white questionnaire format advocated by the Total Design Method advanced by Don Dillman at Washington State University. We observed a favorable response rate for a large questionnaire printed on blue paper; however, if time and resources are limited, use of a small/white questionnaire appears preferable.
    背景与目标:
  • 【术中多普勒彩色血流图用于二尖瓣返流瓣膜修复的决策。100患者的技术和结果。】 复制标题 收藏 收藏
    DOI:10.1161/01.cir.81.2.556 复制DOI
    作者列表:Stewart WJ,Currie PJ,Salcedo EE,Lytle BW,Gill CC,Schiavone WA,Agler DA,Cosgrove DM
    BACKGROUND & AIMS: :Mitral valve repair provides substantial advantages over mitral valve replacement in patients with severe mitral regurgitation. However, because of the possibility of persistent regurgitation, an intraoperative technique is needed to provide an immediate and accurate assessment of the adequacy of the repair before closure of the chest. One hundred patients with pure mitral regurgitation were studied with intraoperative epicardial Doppler color flow mapping immediately before and after valve repair. Intraoperative assessment of the severity of mitral regurgitation showed good agreement with preoperative left ventriculography and with standard precordial Doppler echocardiography before and after surgery. Postrepair intraoperative Doppler studies showed satisfactory surgical results in 92 patients. Postrepair intraoperative Doppler studies in the remaining eight patients demonstrated unsatisfactory results: persistent significant regurgitation in four, systolic anterior motion of the mitral valve with dynamic left ventricular outflow tract obstruction in three, and a persistent flail leaflet in one. In six of the eight patients, further surgery was performed during the same thoracotomy. In two patients, the intraoperative postrepair Doppler findings of persistent regurgitation were confirmed on precordial Doppler studies within 5 days, and mitral reoperation was required. Intraoperative epicardial Doppler color flow mapping provided a "safety net" that ensured a successful outcome in all 100 patients by providing the surgeon with a direct means to assess the success of the operation and the need for further surgery.
    背景与目标: : 在严重二尖瓣反流患者中,二尖瓣修复比二尖瓣置换术具有明显优势。但是,由于存在持续返流的可能性,因此需要一种术中技术来在闭合胸部之前立即准确地评估修复的充分性。在瓣膜修复前后立即通过术中心外膜多普勒彩色血流图研究了一百例纯二尖瓣反流的患者。术中评估二尖瓣反流的严重程度与术前左心室造影和手术前后的标准心前区多普勒超声心动图吻合良好。对术中多普勒检查显示92例患者的手术效果令人满意。其余8例患者的术中多普勒检查显示结果不理想: 4例持续明显反流,3例二尖瓣收缩期前运动,动态左心室流出道梗阻,1例持续连枷小叶。在八名患者中的六名中,在相同的开胸手术中进行了进一步的手术。在两名患者中,在5天内通过心前区多普勒检查证实了术中对后多普勒检查的持续性反流,需要进行二尖瓣再次手术。术中心外膜多普勒彩色血流图提供了 “安全网”,通过为外科医生提供直接评估手术成功和进一步手术需求的直接手段,确保了所有100患者的成功结局。
  • 【[经颅彩色编码双工超声在监测神经危重症患者中的应用]。】 复制标题 收藏 收藏
    DOI:10.1016/s0210-5691(07)74858-1 复制DOI
    作者列表:Abadal JM,Llompart-Pou JA,Homar J,Pérez-Bárcena J,Ibáñez J
    BACKGROUND & AIMS: :Transcranial sonography is a common tool for monitoring neurocritical patients. Transcranial color-coded duplex ultrasonography enables hemodynamic and structural study of the cerebral parenchyma in these patients. Its advantages over conventional ultrasonography are evident and are derived from direct visualization of the vessel to be studied and appropriate adjustment of the sample volume and angle of insonation. The use of ultrasonographic contrast agents enables conclusive findings in practically 100% of cases and allows cerebral perfusion to be studied at the bedside using semiquantitative methods. This review aims to show the applications of transcranial color-coded duplex ultrasonography for monitoring neurocritical patients in intensive care units.
    背景与目标: : 经颅超声检查是监测神经危重症患者的常用工具。经颅彩色编码的双工超声检查可对这些患者的脑实质进行血流动力学和结构研究。与常规超声检查相比,它的优势是显而易见的,并且源于对要研究的血管的直接可视化以及对样品体积和声角的适当调整。使用超声造影剂可以在实际100% 的情况下得出结论,并允许使用半定量方法在床边研究脑灌注。这篇综述旨在展示经颅彩色编码双工超声在重症监护病房中监测神经危重患者的应用。
  • 【使用标准化彩色照片评估前睑缘炎的体征。】 复制标题 收藏 收藏
    DOI:10.1097/ICO.0b013e3182a02e0e 复制DOI
    作者列表:Bunya VY,Brainard DH,Daniel E,Massaro-Giordano M,Nyberg W,Windsor EA,Pearson DJ,Huang J,Maguire MG,Stone RA
    BACKGROUND & AIMS: PURPOSE:To describe a standardized technique for acquiring and viewing photographic images of eyelids, assess the reproducibility and validity of a grading protocol for signs of anterior blepharitis, and to explore whether the signs depend on the eyelid or the area of the eyelid assessed. METHODS:Subjects with anterior blepharitis ranging from none to severe were examined by ophthalmologists at clinical sites. Digital images of the eyelids of subjects were acquired using a protocol that allowed for the calibration of color and luminance. Three ophthalmologists at a centralized reading center applied a novel protocol for grading features of anterior blepharitis from the digital images viewed on color-calibrated monitors. The agreement among graders was assessed using percent agreement and weighted kappa statistics (Kw), and the correlation of photographic and clinical gradings was assessed using Spearman correlation coefficients. RESULTS:Agreement among graders was excellent (Kw > 0.80) on the number of eyelid margin vessels and was substantial (Kw between 0.61 and 0.80) for erythema, collarettes, number of engorged vessels, and number of lashes. Grading of the photographic images and the clinical assessments of erythema and lid debris were moderately correlated (r = 0.27-0.45). The grades for different features depended on whether the upper or lower eyelid, eyelid skin or lid margin, and central or lateral lid were assessed. CONCLUSIONS:The application of a protocol to obtain and display calibrated digital images of eyelids supports the standardized assessment of anterior blepharitis in clinical care and research studies.
    背景与目标:
  • 【经颅彩色编码的双工超声检查用于检测颈内动脉远端狭窄。】 复制标题 收藏 收藏
    DOI:10.3174/ajnr.A0789 复制DOI
    作者列表:Valaikiene J,Schuierer G,Ziemus B,Dietrich J,Bogdahn U,Schlachetzki F
    BACKGROUND & AIMS: BACKGROUND AND PURPOSE:Gradation of high-grade intracranial internal carotid artery (ICA) stenosis poses a challenge to noninvasive neurovascular imaging, which seems critical for angioplasty in the ICA segments C1 and C5. We investigated cutoff values of intracranial ICA stenosis for transcranial color-coded sonography (TCCS) and compared this method with the "gold standard," digital subtraction angiography (DSA). MATERIALS AND METHODS:Forty patients (mean age, 58.9 +/- 13.8 years) with intracranial ICA lesions were prospectively examined by using TCCS and DSA. Two standard TCCS coronal imaging planes were used to evaluate the intracranial ICA. In addition, a control group of 128 volunteers without cerebrovascular disease (mean age, 48.8 +/- 15.9 years) was investigated to establish standard velocity values. RESULTS:DSA confirmed 96 stenoses and 8 occlusions of the intracranial ICA in the study population. In 9% and 7% of cases, stenosis confined to the C1 or C5 segment was >50% and 70%, respectively. Receiver-operating curves demonstrated cutoff values for >70% stenosis in C1 when the peak systolic velocity (PSV) was >200 cm/s (specificity, 100%; sensitivity, 71%) or the C1/submandibular ICA index was >3 (specificity, 93%; sensitivity, 86%). CONCLUSIONS:TCCS is a reliable adjunctive method to detect and quantify significant stenosis of the intracranial ICA. The assessment of the C1/ICA index and peak systolic velocities maximizes the diagnostic accuracy of C1 stenosis to >70% when extracranial ICA stenosis coexists. Further studies need to be performed to compare the diagnostic accuracies of MR angiography and TCCS with that of DSA.
    背景与目标:
  • 【台湾2015年6月28日台塑彩色粉尘爆炸499名烧伤伤亡的分配经验。】 复制标题 收藏 收藏
    DOI:10.1016/j.burns.2016.10.008 复制DOI
    作者列表:Wang TH,Jhao WS,Yeh YH,Pu C
    BACKGROUND & AIMS: OBJECTIVE:To describe the experience of distributing 499 burn casualties of an unexpected event and determine whether patient transfer is associated with patient outcomes measured 2 weeks after the incident. METHODS:All 499 patients injured in the event were included. For the 138 patients transferred to other hospitals after primary distribution, we evaluated whether the transfers were associated with patient severity. Furthermore, we used multinomial logistic regression to investigate the association of patient transfer with patient outcomes after controlling for age, gender, total burn surface area (TBSA), final hospital level, wound infection, and patient pneumonia. RESULTS:We determined that on-site triage differed significantly from hospital triage (p<0.001). Furthermore, the secondary distribution enabled the transfer of a high number of patients to medical centers based on the availability of beds; however, such transfers were not associated with patient outcomes (p>0.05). Factors associated with patient outcomes were wound infection and TBSA (p<0.001). CONCLUSIONS:In case of inadequate burn centers, satisfactory patient outcomes can be achieved by the immediate treatment of patients, despite the treating hospitals being lower-level hospitals. Regardless of the hospital level, immediate treatment of burn patients is crucial to reducing mortality.
    背景与目标:
  • 【在正常人类胎儿的整个妊娠过程中,颜色M模式传播速度 (但与舒张早期流入速度之比却没有变化)。】 复制标题 收藏 收藏
    DOI:10.1002/uog.5303 复制DOI
    作者列表:Moon-Grady AJ,Taylor D,Bennett SH,Hornberger LK,Tacy TA
    BACKGROUND & AIMS: OBJECTIVES:Color M-mode propagation velocity (Vp) is a measure of diastolic function in adults and, when combined with early diastolic inflow velocity (E), the ratio E/Vp reflects ventricular filling pressure. Early detection of diastolic compromise may benefit fetal patients at risk for developing heart failure. The objectives of this study were to measure values for Vp and inflow peak E in a group of normal fetuses, to analyze age-dependent alterations in these measurements, and to evaluate the interobserver and intraobserver variability of the measurements. METHODS:Thirty-two normal fetuses at between 20 and 35 weeks' gestation underwent echocardiography. Color M-mode Vp was measured from the four-chamber view for the right (RV) and left (LV) ventricles, and mitral and tricuspid inflow velocities were determined by pulsed-wave Doppler ultrasound. The values obtained were compared with previously reported findings in adults. RESULTS:Adequate tracings were obtainable in 23 patients for the RV and 29 for the LV. Mean Vp values for the RV (15.3 +/- 3.2 cm/s) and LV (20.8 +/- 5.6 cm/s) were lower than normal adult values, and Vp values were significantly lower for the RV than the LV (P < 0.001). Applying Bazett's heart rate correction, values for RV (23.4 +/- 4.8 cm/s) and LV (31.9 +/- 8.7 cm/s) remained lower than normal adult values. There was a linear correlation of Vp with gestational age for the RV (R = 0.69, P < 0.001), and the ratio of E/Vp corrected for heart rate for the RV (1.51 +/- 0.26) remained constant throughout gestation. Interobserver bias was high but intraobserver bias low, at 19 and 1.1%, respectively. CONCLUSIONS:Vp is lower in fetal than in adult life. Vp for the RV changes in a manner indicative of improving diastolic function throughout normal gestation, providing insight into the alterations in diastolic function with gestation that contribute to increases in cardiac output. The use of Vp to assess diastolic function disturbance in fetuses is feasible, but high interobserver variability is problematic.
    背景与目标:
  • 【果蝇髓质中的色觉回路。】 复制标题 收藏 收藏
    DOI:10.1016/j.cub.2008.02.075 复制DOI
    作者列表:Morante J,Desplan C
    BACKGROUND & AIMS: BACKGROUND:Color vision requires comparison between photoreceptors that are sensitive to different wavelengths of light. In Drosophila, this is achieved by the inner photoreceptors (R7 and R8) that contain different rhodopsins. Two types of comparisons can occur in fly color vision: between the R7 (UV sensitive) and R8 (blue- or green sensitive) photoreceptor cells within one ommatidium (unit eye) or between different ommatidia that contain spectrally distinct inner photoreceptors. Photoreceptors project to the optic lobes: R1-R6, which are involved in motion detection, project to the lamina, whereas R7 and R8 reach deeper in the medulla. This paper analyzes the neural network underlying color vision into the medulla. RESULTS:We reconstruct the neural network in the medulla, focusing on neurons likely to be involved in processing color vision. We identify the full complement of neurons in the medulla, including second-order neurons that contact both R7 and R8 from a single ommatidium, or contact R7 and/or R8 from different ommatidia. We also examine third-order neurons and local neurons that likely modulate information from second-order neurons. Finally, we present highly specific tools that will allow us to functionally manipulate the network and test both activity and behavior. CONCLUSIONS:This precise characterization of the medulla circuitry will allow us to understand how color vision is processed in the optic lobe of Drosophila, providing a paradigm for more complex systems in vertebrates.
    背景与目标:
  • 【用于促进酵母U4/U6 RNA双链体退绕的多步模型。】 复制标题 收藏 收藏
    DOI:10.1093/nar/gkw686 复制DOI
    作者列表:Rodgers ML,Didychuk AL,Butcher SE,Brow DA,Hoskins AA
    BACKGROUND & AIMS: :The small nuclear RNA (snRNA) components of the spliceosome undergo many conformational rearrangements during its assembly, catalytic activation and disassembly. The U4 and U6 snRNAs are incorporated into the spliceosome as a base-paired complex within the U4/U6.U5 small nuclear ribonucleoprotein (tri-snRNP). U4 and U6 are then unwound in order for U6 to pair with U2 to form the spliceosome's active site. After splicing, U2/U6 is unwound and U6 annealed to U4 to reassemble the tri-snRNP. U6 rearrangements are crucial for spliceosome formation but are poorly understood. We have used single-molecule Förster resonance energy transfer and unwinding assays to identify interactions that promote U4/U6 unwinding and have studied their impact in yeast. We find that U4/U6 is efficiently unwound using DNA oligonucleotides by coupling unwinding of U4/U6 stem II with strand invasion of stem I. Unwinding is stimulated by the U6 telestem, which transiently forms in the intact U4/U6 RNA complex. Stabilization of the telestem in vivo results in accumulation of U4/U6 di-snRNP and impairs yeast growth. Our data reveal conserved mechanisms for U4/U6 unwinding and indicate telestem dynamics are critical for tri-snRNP assembly and stability.
    背景与目标: : 剪接体的小核RNA (snRNA) 成分在其组装,催化活化和拆卸过程中会经历许多构象重排。U4和U6 snrna作为U4/U6.U5小核核糖核蛋白 (tri-snRNP) 内的碱基配对复合物掺入剪接体中。然后将U4和U6展开,以便U6与U2配对以形成剪接体的活性位点。拼接后,将U2/U6展开,并将U6退火至U4以重新组装tri-snRNP。U6重排对于剪接体的形成至关重要,但知之甚少。我们已经使用单分子f ö rster共振能量转移和退绕测定法来鉴定促进U4/U6退绕的相互作用,并研究了它们在酵母中的影响。我们发现,通过将U4/U6茎II的退绕与茎I的链侵袭偶联,使用DNA寡核苷酸有效地解开了U4/U6。U6远干刺激解旋,该远干在完整的U4/U6 RNA复合物中瞬时形成。体内远端的稳定会导致U4/U6 di-snRNP的积累并损害酵母的生长。我们的数据揭示了U4/U6退绕的保守机制,并表明远程动力学对于tri-snRNP组装和稳定性至关重要。
  • 【人类视觉系统中多色通道的时空特性。】 复制标题 收藏 收藏
    DOI:10.1167/16.9.14 复制DOI
    作者列表:Kondo D,Motoyoshi I
    BACKGROUND & AIMS: :Psychophysical and neurophysiological evidence argues for neural channels in V1 selectively sensitive to intermediate hues between the cardinal axes of opponent-color space. The present study examined if these multiple-color channels are selective for other visual features analyzed by V1 such as orientation, spatial frequency, and motion direction. Using a conventional masking paradigm, we measured detection thresholds for an isoluminant grating modulated along a particular hue angle either in the presence or absence of a bandpass noise mask that varied in hue angle, orientation, spatial frequency, and motion direction. In line with previous studies, thresholds for the test grating were selectively elevated by noise masks with hue angles similar to that of the test. Hue-selective masking was substantially reduced if test and mask were oriented orthogonally or differed in spatial frequency, but thresholds remained elevated if the mask drifted in the direction opposite to that of the test. Masking also revealed components selective for hue angle, but not for orientation. The results support the notion that multiple-color channels partly involve visual units selective for orientation and spatial frequency but largely nonselective for motion direction.
    背景与目标: : 心理物理和神经生理学证据表明,V1中的神经通道对对手颜色空间的主轴之间的中间色调选择性敏感。本研究检查了这些多色通道是否对V1分析的其他视觉特征 (例如方向,空间频率和运动方向) 具有选择性。使用传统的掩蔽范例,我们测量了在存在或不存在色相角,方向,空间频率和运动方向变化的带通噪声掩模的情况下,沿特定色相角调制的异发光光栅的检测阈值。与先前的研究一致,通过具有与测试相似的色相角的噪声掩模选择性地提高了测试光栅的阈值。如果测试和掩模正交定向或空间频率不同,则色调选择性掩蔽会大大减少,但是如果掩模沿与测试方向相反的方向漂移,则阈值仍然会升高。掩蔽还揭示了对色调角度有选择性但对方向没有选择性的成分。结果支持以下观点: 多色通道部分涉及对方向和空间频率具有选择性的视觉单元,但对运动方向却基本上没有选择性。
  • 【照明假设解释了对颜色域中深刻模棱两可的刺激的感知解释中的个体差异: “衣服”。】 复制标题 收藏 收藏
    DOI:10.1167/17.4.5 复制DOI
    作者列表:Wallisch P
    BACKGROUND & AIMS: :There has been considerable interest in a stimulus ("the dress") that yields starkly divergent subjective color percepts between observers. It has been proposed that individual differences in the subjective interpretation of this stimulus are due to the different assumptions that individuals make about how the dress was illuminated. In this study, we address this possible explanation empirically by reporting on data from ∼13,000 observers who were surveyed online. We show that assumptions about the illumination of the dress-i.e., whether the stimulus was illuminated by natural or artificial light or whether it was in a shadow-strongly affects the subjective interpretation of observers, compared to demographic factors, such as age or gender, which have a relatively smaller influence. We interpret these findings in a Bayesian framework by also showing that prior exposure to long- or short-wavelength lights due to circadian type shapes the subjective experience of the dress stimulus in theoretically expected ways.
    背景与目标: : 人们对刺激 (“着装”) 产生了极大的兴趣,这种刺激在观察者之间产生了明显不同的主观色彩感知。有人提出,这种刺激的主观解释中的个体差异是由于个体对衣服的照明方式的不同假设所致。在这项研究中,我们通过报告来自在线调查的约13,000名观察员的数据,以经验方式解决了这一可能的解释。我们表明,关于dress-i.e照明的假设,无论刺激是由自然光还是人造光照射,还是在阴影中,都强烈影响观察者的主观解释,与年龄或性别等人口统计学因素相比,影响相对较小。我们在贝叶斯框架中解释了这些发现,还表明由于昼夜节律类型而预先暴露于长波或短波长光中以理论上预期的方式塑造了着装刺激的主观体验。
  • 【使用能量色散超导过渡边缘传感器光谱的少光子彩色成像。】 复制标题 收藏 收藏
    DOI:10.1038/srep45660 复制DOI
    作者列表:Niwa K,Numata T,Hattori K,Fukuda D
    BACKGROUND & AIMS: :Highly sensitive spectral imaging is increasingly being demanded in bioanalysis research and industry to obtain the maximum information possible from molecules of different colors. We introduce an application of the superconducting transition-edge sensor (TES) technique to highly sensitive spectral imaging. A TES is an energy-dispersive photodetector that can distinguish the wavelength of each incident photon. Its effective spectral range is from the visible to the infrared (IR), up to 2800 nm, which is beyond the capabilities of other photodetectors. TES was employed in this study in a fiber-coupled optical scanning microscopy system, and a test sample of a three-color ink pattern was observed. A red-green-blue (RGB) image and a near-IR image were successfully obtained in the few-incident-photon regime, whereas only a black and white image could be obtained using a photomultiplier tube. Spectral data were also obtained from a selected focal area out of the entire image. The results of this study show that TES is feasible for use as an energy-dispersive photon-counting detector in spectral imaging applications.
    背景与目标: : 在生物分析研究和工业中,越来越需要高灵敏度的光谱成像,以从不同颜色的分子中获得最大的信息。我们介绍了超导过渡边缘传感器 (TES) 技术在高灵敏度光谱成像中的应用。TES是一种能量色散光电探测器,可以区分每个入射光子的波长。它的有效光谱范围是从可见光到红外 (IR),高达2800  nm,这超出了其他光电探测器的能力。在这项研究中,TES在光纤耦合光学扫描显微镜系统中使用,并观察到三色墨水图案的测试样品。在少数入射光子中成功获得了红绿蓝 (RGB) 图像和近红外图像,而使用光电倍增管只能获得黑白图像。还从整个图像中的选定焦点区域获得了光谱数据。这项研究的结果表明,TES在光谱成像应用中用作能量色散光子计数检测器是可行的。
  • 【通过彩色多普勒图像中速度矢量的表面积分估算体积流速。】 复制标题 收藏 收藏
    DOI:10.1016/s0894-7317(05)80015-x 复制DOI
    作者列表:Sun Y,Ask P,Janerot-Sjöberg B,Eidenvall L,Loyd D,Wranne B
    BACKGROUND & AIMS: :A new Doppler echocardiographically based method has been developed to quantify volume flow rate by surface integration of velocity vectors (SIVV). Electrocardiographic-gated color Doppler images acquired in two orthogonal planes were used to estimate volume flow rate through a bowl-shaped surface at a given time and distance from the probe. To provide in vitro validation, the method was tested in a hydraulic model representing a pulsatile flow system with a restrictive orifice. Accurate estimates of stroke volume (+/- 10%) were obtained in a window between 1.2 and 1.6 cm proximal to the orifice, just before the region of prestenotic acceleration. By use of the Bernoulli's equation, the estimated flows were used to generate pressure gradient waveforms across the orifice, which agreed well with the measured flows. To demonstrate in vivo applicability, the SIVV method was applied retrospectively to the determination of stroke volume and subaortic flow from the apical three-chamber and five-chamber views in two patients. Stroke volume estimates along the left ventricular outflow tract showed a characteristic similar to that in the in vitro study and agreed well with those obtained by the Fick oxygen method. The region where accurate measurements can be obtained is affected by instrumental factors including Nyquist velocity limit, wall motion filter cutoff, and color flow sector angle. The SIVV principle should be useful for quantitative assessment of the severity of valvular abnormalities and noninvasive measurement of pulsatile volume flows in general.
    背景与目标: : 已经开发了一种新的基于多普勒超声心动图的方法,用于通过速度矢量的表面积分 (SIVV) 来量化体积流速。在两个正交平面中采集的心电图门控彩色多普勒图像用于估计在给定时间和距探头的距离下通过碗状表面的体积流速。为了提供体外验证,该方法在代表具有限制性孔口的脉动流系统的水力模型中进行了测试。在狭窄前加速区域之前,在靠近孔口的1.2和1.6厘米之间的窗口中获得了中风量的准确估计 (/- 10%)。通过使用伯努利方程,估计的流量用于生成整个孔口的压力梯度波形,该波形与测得的流量非常吻合。为了证明在体内的适用性,将SIVV方法回顾性地用于从两名患者的心尖三腔和五腔视图确定中风量和主动脉下血流。沿左心室流出道的每搏输出量估计值显示出与体外研究相似的特征,并且与通过Fick氧气方法获得的结果非常吻合。可以获得精确测量的区域受仪器因素的影响,包括奈奎斯特速度极限,壁运动滤镜截止和彩色流扇形角。SIVV原理通常可用于定量评估瓣膜异常的严重程度和无创测量脉动体积流量。
  • 【子宫内肺隔离症自发消退的彩色和双工多普勒超声检查。】 复制标题 收藏 收藏
    DOI:10.7863/jum.1996.15.11.789 复制DOI
    作者列表:Smulian JC,Guzman ER,Ranzini AC,Benito CW,Vintzileos AM
    BACKGROUND & AIMS: Bronchopulmonary sequestration is a congenital abnormality of nonfunctional pulmonary tissue that lacks normal connections with the bronchial tree. The sequestered tissue typically receives the majority of its blood supply from systemic vessels, most often the distal thoracic or upper abdominal aorta. These lesions often are associated with fetal hydrops, polyhydramnios, and persistent masses postnatally. Bronchopulmonary sequestrations are thought to require resection owing to their predisposition for chronic pulmonary infections later in life. However, spontaneous in utero resolution of these lesions can occur. This report describes the real time, color Doppler, and duplex Doppler ultrasonographic investigation of an intrathoracic bronchopulmonary sequestration that resolved spontaneously. Our investigation of this case provides new insight into a possible mechanism for spontaneous regression of bronchopulmonary sequestration.

    背景与目标: 支气管肺隔离症是一种先天性的非功能性肺组织异常,与支气管树缺乏正常的连接。隔离的组织通常从全身血管 (通常是远端胸主动脉或上腹主动脉) 获得大部分血液供应。这些病变通常与胎儿积水,羊水过多和出生后持续性肿块有关。由于支气管肺病在以后的生活中易患慢性肺部感染,因此需要切除。但是,这些病变可能会在子宫内自发消退。本报告描述了自发解决的胸内支气管肺隔离症的实时,彩色多普勒和双工多普勒超声检查。我们对该病例的研究为支气管肺隔离自发消退的可能机制提供了新的见解。

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