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Del Pozzi Andrew T AT Departments of Pediatrics and Physiology, New York Medical College, - - 2014
Hyperventilation and reduced cerebral blood flow velocity can occur in postural tachycardia syndrome (POTS). We studied orthostatically intolerant patients, with suspected POTS, with a chief complaint of upright dyspnea. On the basis of our observations of an immediate reduction of cerebral blood flow velocity with orthostasis, we hypothesize that the ...
Wieling W W Departments of Internal Medicine, Academic Medical Centre University of Amsterdam, Amsterdam, The - - 2014
Standing upright challenges the cardiovascular system as the pull of gravity displaces about 70% of the circulating blood volume to below heart level, much of it to the compliant veins of the dependent limbs and the pelvic organs. In patients with autonomic failure due to neurodegenerative diseases, the normal cardiovascular ...
Rose Jason P JP University of Toledo, Toledo, - - 2014
Blood is a valuable resource, but most people do not donate. One deterrent to blood donation is the anticipation of vasovagal symptoms (e.g., dizziness, nausea, and fainting), despite the fact that such symptoms typically affect a small proportion of donors. The current research examined norm perceptions regarding vasovagal symptom experiences ...
Ditto Blaine - - 2014
Objective: Observing or hearing about illness in another person can lead to reports of similar symptoms. Reports can occasionally be widespread. However, it has been difficult to document whether this is the result of genuine illness or the expression of anxiety with physical terminology. This study examined the effects of ...
Phillips Aaron A AA 1University of British - - 2014
Individuals with spinal cord injury (SCI) above the T6 spinal segment suffer from orthostatic intolerance. How cerebral blood flow (CBF) responds to orthostatic challenges in SCI is poorly understood. Furthermore, it is unclear how interventions meant to improve orthostatic tolerance in SCI influence CBF. This study aimed to examine: 1) ...
Tugba Barsan B 1 Department of Pediatric Cardiology, Eskisehir Osmangazi University, Eskisehir, - - 2014
Introduction: We aimed to evaluate changes in the cerebral blood supply in children during vasovagal syncope and to clarify the diagnostic value of transcranial Doppler for vasovagal syncope. Materials and methods: Patients were divided into three groups. Group 1 consisted of 31 patients who were symptomatic and whose head-up tilt ...
Cheng Ran R University of Kentucky, Department of Biomedical Engineering, Lexington, Kentucky - - 2014
ABSTRACT. Significant drops in arterial blood pressure and cerebral hemodynamics have been previously observed during vasovagal syncope (VVS). Continuous and simultaneous monitoring of these physiological variables during VVS is rare, but critical for determining which variable is the most sensitive parameter to predict VVS. The present study used a novel ...
Sirek Adam S AS Wyle Integrated Science and Engineering, Houston, TX, USA. - - 2014
Ocular changes have been noted during long-duration spaceflight; we studied central retinal artery (CRA) blood flow using Doppler before, during, and after long-term microgravity exposure in astronauts compared with data from a control group of nonastronauts subjected to head-down tilt (HDT). Available Doppler spectra of International Space Station (ISS) crewmembers ...
Endo Ayumi A Department of Pediatrics and Child Health, Nihon University School of Medicine, 30-1 Oyaguchi-Kamicho, Itabashi-ku, Tokyo, 173-8610, - - 2014
Orthostatic dysregulation (OD) has been classified into subtypes by heart rate and blood pressure; however, the hemodynamics of brains have not yet been revealed. Therefore, we investigated changes in cerebral blood flow and oxygenation during an active standing test to clarify the pathophysiology of two subtypes: postural tachycardia syndrome (POTS) ...
Hashimdeen S H - - 2013
This study investigates the effect of print head design on the electrohydrodynamic printed resolution of silk fibroin. Needles with large orifices measuring at 800μm were used to build five different print heads. The print heads were manufactured, tested, and optimized using four different silk fibroin solution concentrations of 10wt.%, 15wt.%, ...
Phillips Aaron A - - 2013
Significant cardiovascular and autonomic dysfunction occurs following a spinal cord injury (SCI). Two major conditions arising from autonomic dysfunction are orthostatic hypotension and autonomic dysreflexia (i.e., severe acute hypertension). Effective regulation of cerebral blood flow (CBF) is essential to offset the potential drastic alterations in cerebral perfusion pressure. In the ...
Mezei Zsolt - - 2013
Demyelination in multiple sclerosis (MS) may cause damage to the vegetative nervous system. Our objective was to examine cerebral autoregulation assessed via blood pressure and cerebral blood flow velocity fluctuations during head-up tilt table testing. We also investigated the effects of high-dose intravenous corticosteroid treatment. Transcranial Doppler registration of middle ...
Ichikawa D - - 2013
The incidence of orthostatic intolerance is elevated in endurance-trained individuals. We sought to test the hypothesis that aerobic endurance training is associated with an attenuated control of the cerebral vasculature. Endurance trained (ET, n = 13) and age-matched untrained (UT, n = 11) individuals (peak O2 consumption, mean ± SEM; 63 ± 1 vs 42 ± 1 mL/min/kg, P < 0.05) were examined ...
Perlmuter Lawrence C - - 2013
The magnitude of increase in systolic blood pressure in response to the shift from supine to upright posture is considered to reflect the adequacy of orthostatic regulation. Orthostatic integrity is largely maintained by the interaction between the skeletal muscle pump, neurovascular compensation, neurohumoral effects, and cerebral blood flow regulation. Various ...
Stewart Julian M JM Departments of Pediatrics, Physiology, and Medicine, The Maria Fareri Children’s Hospital, NY, USA. - - 2013
The autonomic nervous system, adequate blood volume, and intact skeletal and respiratory muscle pumps are essential components for rapid cardiovascular adjustments to upright posture (orthostasis). Patients lacking sufficient blood volume or having defective sympathetic adrenergic vasoconstriction develop orthostatic hypotension (OH), prohibiting effective upright activities. OH is one form of orthostatic ...
van Dijk J Gert - - 2013
The definition of syncope has clinical and pathophysiological parts. The clinical part is that syncope is a form of transient loss of consciousness (TLOC), while the pathophysiological element is that syncope differs from other forms of TLOC by virtue of the basis of true syncope - specifically cerebral hypoperfusion. As ...
Davis Philip - - 2013
An activity profile of competitive 3 × 2-min novice-level amateur boxing was created based on video footage and postbout blood [La] in 32 male boxers (mean ± SD) age 19.3 ± 1.4 y, body mass 62.6 ± 4.1 kg. Winners landed 18 ± 11 more punches than losers by applying ...
Foulkes Andrew J - - 2013
Here we examine the relationship between the perception of heading and flow parsing. In a companion study we have investigated the pattern of dependence of human heading estimation on the quantity (amount of dots per frame) and quality (amount of directional noise) of motion information in an optic flow field. ...
Kountouriotis Georgios K GK Institute of Psychological Sciences, University of Leeds, Leeds LS2 9JT, UK; and Institute for Transport Studies, University of Leeds, Leeds LS2 9JT, UK; e-mail: - - 2013
Optic flow can be used by humans to determine their direction of heading as well as controlling steering. Dot-flow displays have been widely used to investigate these abilities but it is unclear whether photorealistic textures would provide better information for controlling high-speed steering. Here, we examine the accuracy of heading ...
Tsai Keng-Kuang - - 2012
The regulation of nasal mucosa blood flow (NMBF) is affected by multiple factors, such as the autonomic nervous system, medications, temperature, humidity, endocrine, even emotional stress and vision. The effects of postural changes on NMBF have been described in numerous studies. However, the results are far from consistent due to ...
Ogawa Yojiro - - 2013
Diuretic-induced mild hypovolemia with hemoconcentration reportedly improves dynamic cerebral autoregulation, whereas central hypovolemia without hemoconcentration induced by lower body negative pressure (LBNP) has no effect or impairs dynamic cerebral autoregulation. This discrepancy may be explained by different blood properties, by degrees of central hypovolemia, or both. We investigated the effects ...
Zhang Hong-Liang - - 2012
OBJECTIVE: Cerebral autoregulation (CA) is the mechanism by which constant cerebral blood flow is maintained despite changes in cerebral perfusion pressure. CA can be evaluated by dynamic monitoring of cerebral blood flow velocity (CBFV) with transcranial Doppler sonography (TCD). The present study aimed to explore CA in chronic anxiety. METHODS: ...
Nagatani Kimihiro - - 2012
Data on the optimal head position for patients with acute ischemic stroke are unavailable. We evaluated the effects of mild head-down tilt (HDT) on cerebral blood flow (CBF) in mice during bilateral common carotid artery occlusion (BCCAO). We used mice with BCCAO (35 minutes) and divided these into 2 groups ...
Nagafusa Yuko - - 2012
BACKGROUND: Single-photon emission computed tomography (SPECT) is used as an ancillary diagnostic tool in clinical psychiatry. A variety of SPECT studies has been conducted on the findings and the factors that affect the findings, and there is a possibility that age has an effect on cerebral blood flow. We used ...
Warren Paul A PA School of Psychological Sciences, The University of Manchester, Manchester, UK. - - 2012
We have recently suggested that neural flow parsing mechanisms act to subtract global optic flow consistent with observer movement to aid in detecting and assessing scene-relative object movement. Here, we examine whether flow parsing can occur independently from heading estimation. To address this question we used stimuli comprising two superimposed ...
Slapak Colleen - - 2011
ATSO is in a unique position to break down organizational silos between hospitals and blood centers through the development of a collaborative relationship between the two entities. Use of the TSO as blood center staff centralizes the role into a consultative position thereby retaining the independence of the hospitals. The ...
Que Yanhong - - 2011
The aim of this study is to evaluate the contrast-enhanced ultrasound (CEUS) features of peritoneal metastases. Unenhanced ultrasound and CEUS were conducted in 25 patients who had confident diagnoses of peritoneal metastases after ultrasound-guided biopsies of peritoneum. B-mode sonograms, color Doppler, CEUS pattern and quantitative analysis of blood perfusion in ...
Varma Neelam - - 2011
Applications of flow cytometry in pediatric cancers have expanded substantially in recent years. In acute leukemias, the commonest childhood cancer, flow cytometry can now define complex antigenic profiles that are associated with specific cytogenetic/molecular defects and can also directly identify BCR-ABL fusion protein. Flow cytometry based scoring system has been ...
Bommer Martin - - 2011
BACKGROUND: Cerebrospinal fluid samples with doubtful morphologic interpretation are a common problem in the workup of patients with clinical signs for leptomeningeal disease. The authors report on the combination of morphology and flow cytometry in the diagnosis of leptomeningeal disease in patients with radiological, clinical, or cytological findings suspicious for ...
Schmidt René - - 2011
Preoperative embolization of vertebral metastases has been shown to lower intraoperative blood loss. Nevertheless, excessive up to life-threatening blood loss can occur despite embolization. We therefore decided to evaluate possible parameters for predicting significant blood loss in a surgically homogeneous group of patients with vertebral metastases. Patients with vertebral metastases ...
Yang Dal Mo - - 2010
The purpose of this study was to describe the sonographic findings of acute vasitis. This was a retrospective analysis of 12 cases of acute vasitis. The following gray scale and color Doppler sonographic features were analyzed: location, echogenicity of the lesion, presence of hydrocele, epididymal involvement, and blood flow within ...
Gao Jing - - 2010
The objective of this report was to describe and potentially explain differences of intrarenal color Doppler sonography (CDUS) manifestations between blood flow turbulence and twinkling artifact. We retrospectively reviewed 32 cases with appearance of focally increased color Doppler signal on intrarenal CDUS from May 1, 2007, to February 28, 2009. ...
Tarhan Serdar - - 2011
We aimed to investigate the long-term effect of microsurgical inguinal varicocelectomy on testicular blood flow using color Doppler sonography (CDS) in this observational study. A total of 30 patients clinically diagnosed with left varicocele who underwent a microsurgical inguinal varicocelectomy were examined 3 times with CDS for testicular blood flow ...
Zhu Jiaan - - 2012
To investigate the complex appearance of vascularity of sacroiliac joint (SIJ) in ankylosing spondylitis. Sixty-eight patients and 35 controls were included in the study. Blood flow was examined at the SIJ by using color Doppler ultrasonography (CDUS). The location of color flow signs and flow pattern were observed. Arteries do ...
Gallicchio Jason - - 2010
A new class of observables is introduced which aims to characterize the superstructure of an event, that is, features, such as color flow, which are not determined by the jet four-momenta alone. Traditionally, an event is described as having jets which are independent objects; each jet has some energy, size, ...
de Castro Luis E Fernández - - 2010
PURPOSE: To develop a bead-flow pattern for visualizing and comparatively quantifying fluid movement using a torsional or longitudinal ultrasound (US) phaco handpiece. SETTING: Magill Laser Center, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: Visualization and quantification of intraocular fluid dynamics were evaluated by injecting neutrally buoyant, collagen-coated ...
Woodring T Casey - - 2011
Objective. To determine the accuracy of ultrasound and color flow Doppler to diagnose placenta accreta. Methods. Respectively, ultrasound images consistent with signs of placenta accreta (concomitant previa, numerous vascular lacunae, absent lower uterine segment between bladder-placenta, turbulent or complicated blood flow at the uteroplacental interface) were correlated with findings at the time ...
Schnier Lisa M - - 2010
A 4-year-old male, castrated Saint Bernard was evaluated for acute onset of lethargy and collapse. Moderately severe anemia and splenomegaly were noted. Immune mediated hemolytic anemia was initially suspected. Abdominal ultrasound demonstrated an absence of splenic blood flow. Splenic torsion was confirmed on exploratory laparotomy and a splenectomy was performed.
Uejima Tokuhisa - - 2010
A new mathematical method for estimating velocity vectors from color Doppler datasets is proposed to image blood flow dynamics; this method has been called echodynamography or vector flow mapping (VFM). In this method, the concept of stream function is exploited to expand a 2-D distribution of radial velocities in polar ...
Kurokawa Satoshi - - 2010
PURPOSE: No groups have yet succeeded in identifying the need for re-repair of residual shunt after surgical repair of ventricular septal defect (VSD) based on quantitative evaluation of the ratio of the pulmonary blood flow to the systemic blood flow (Qp/Qs) by transesophageal echocardiography (TEE). Hence, we studied the accuracy ...
Robertson H Thomas - - 2010
This study was designed to validate a high-resolution method to measure regional ventilation (VA) in small laboratory animals, and to compare regional Va and perfusion (Q) before and after methacholine-induced bronchoconstriction. A mixture of two different colors of 0.04-microm fluorescent microspheres (FMS) was aerosolized and administered to five anesthetized, mechanically ...
Fontes P R - - 2010
Color stability of swine blood was studied over 12 weeks of storage in plastic bags, after pH (7.40, 6.70, or 6.00) adjustment, saturation with carbon monoxide (CO) and spray-drying. CO-treated dried blood presented a redder color and higher reflectance between 610 and 700 nm, compared to a brownish-red color and ...
Khalili Majid - - 2010
Throughout history, illustrations had played a key role in the promotion and evolution of medicine by providing a medium for transmission of scientific observations. Due to religious prohibitions, color drawings of the human body did not appear in medieval Persia and during the Islamic Golden Age. This tradition, however, has ...
G?tze A - - 2010
The goals of the present study were to measure mammary blood flow volume (BFV) during the first 12 wk of lactation in dairy cows by using color Doppler sonography and to determine what affects the mammary blood flow. Forty cows were examined via color Doppler sonography on d 1, 7, ...
Welsh Michelle M Medical Research Council Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, Edinburgh, United - - 2010
Regulation of blood flow through the testicular microvasculature by vasomotion is thought to be important for normal testis function as it regulates interstitial fluid (IF) dynamics which is an important intra-testicular transport medium. Androgens control vasomotion, but how they exert these effects remains unclear. One possibility is by signalling via ...
Li Juanqing - - 2009
OBJECTIVE: The purpose of this series was to describe the transvaginal color pulsed Doppler sonographic features of epithelioid trophoblastic tumors (ETTs) and to evaluate whether there were specific sonographic criteria to accurately distinguish them from other lesions. METHODS: Seven cases of ETTs treated in the Women's Hospital of Zhejiang University ...
Bhandal Jitender - - 2009
CASE DESCRIPTION: A 13-year-old neutered female Keeshond-cross was evaluated because of a history of melena, anemia, hematemesis, vomiting, and high serum liver enzyme activities over a 1.5-year period. CLINICAL FINDINGS: Abdominal ultrasonography revealed a hyperechoic mass in the gallbladder. In the gallbladder mass itself, a distinct linear blood flow pattern ...
Auslender R - - 2009
OBJECTIVE: To propose, in cases with coiling of the ovarian vessels, a classification of severity of torsion based on Doppler and gray-scale ultrasound findings and to suggest a treatment strategy for each situation. METHODS: Seventeen patients were examined in a gynecological emergency room between December 1995 and February 2003 due ...
Middleton William D - - 2009
OBJECTIVE: The purpose of this study was to determine the reliability of sonographic visualization of the normal extrapelvic vas deferens and to analyze its appearance and dimensions. METHODS: Scans of the scrotum and spermatic cords were obtained in 25 fertile volunteers. Identification of the vas deferens was attempted bilaterally in ...
Kozakowski Kristin A - - 2009
PURPOSE: The major indication for adolescent left varicocelectomy is testicular asymmetry. However, a period of observation is often recommended preoperatively to determine if the asymmetry resolves, persists or progresses. We investigated whether varicocele grade or the duplex Doppler ultrasound measurements of peak retrograde flow and mean vein diameter could be ...
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