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Results 101 - 150 of 2066
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Wuerzner Gregoire - - 2012
The prevalence of both hypertension and vitamin D deficiency is high. The discovery of the vitamin D receptor and its possible effects on components of the cardiovascular system influencing blood pressure, such as the renin angiotensin system, the heart, the kidney and the blood vessels, has generated the hope that ...
Shoemaker J Kevin - - 2012
Cardiovascular arousal is associated with patterned cortical activity changes. Head-down tilt bed rest dimishes baroreflex-mediated cardiac control. The present study tested the hypothesis that head-down bed rest deconditioning would modify the forebrain organization for heart rate control during baroreflex unloading. Heart rate (HR) variability (HRV), blood pressure and plasma hormones ...
Demir Mehmet - - 2012
Nondipper hypertension is associated with increased cardiovascular morbidity and mortality. Vitamin D deficiency is associated with cardiovascular diseases such as coronary artery disease, heart failure, and hypertension. Vitamin D deficiency activates the renin-angiotensin-aldosterone system, which affects the cardiovascular system. For this reason, a relationship between vitamin D deficiency and nondipper ...
Grønbaek H - - 2012
BACKGROUND: Activation of Kupffer cells may be involved in the pathogenesis of portal hypertension by release of vasoconstrictive substances and fibrosis due to co-activation of hepatic stellate cells. AIM: To study soluble plasma (s) CD163, a specific marker of activated macrophages, as a biomarker for portal hypertension in patients with ...
Kohli Nupur R - - 2012
OBJECTIVE:: To investigate the role of vitamin D in explaining ethnic differences in blood pressure among three ethnic groups in the Netherlands (ethnic Dutch, African Surinamese, and south Asian Surinamese). METHODS:: Data were derived from the 'Surinamese in the Netherlands: study on ethnicity and health' study, a population-based observational study. ...
Hervás Daniel - - 2012
BACKGROUND:: The factors that determine the initiation and persistence of yearly epidemics of respiratory syncytial virus (RSV) bronchiolitis are not well known. A limited number of studies have found that meteorologic conditions could be associated with RSV activity. OBJECTIVES:: We analyze the association of certain atmospheric conditions to RSV activity, ...
Zhou Yan - - 2012
BACKGROUND: Information is limited about the correlation between cardiovascular risk factors (CRFs) and autonomic nervous system (ANS) activity in children. METHODS: In all, 180 children aged 9 to 11 years were enrolled. Heart rate variability, obtained by 24-hour Holter recordings, was analyzed for ANS activity by measuring standard deviation of ...
Tang Kit Tzu - - 2012
Prostheses are prescribed to restore the mobility of people with amputated lower limbs. Monitoring the prosthesis wearing times and physical activity of prosthesis users would provide invaluable information regarding rehabilitation progress and suitability of the prosthesis. The validation of a method to determine wearing times and physical activity state, as ...
Kolt Gregory S - - 2012
We compared the effectiveness of 2 physical activity prescriptions delivered in primary care--the standard time-based Green Prescription and a pedometer step-based Green Prescription--on physical activity, body mass index (BMI), blood pressure, and quality of life in low-active older adults. We undertook a randomized controlled trial involving 330 low-active older adults ...
Hadj-Ahmed Mohamed Amine - - 2012
In nonsedated newborn lambs, nasal pressure support ventilation (nPSV) can lead to an active glottal closure in early inspiration, which can limit lung ventilation and divert air into the digestive system, with potentially deleterious consequences. During volume control ventilation (nVC), glottal closure is delayed to the end of inspiration, suggesting ...
Rietveld Ivo B - - 2012
Enantiomer resolution is much sought after for pharmaceutical applications, because many optically active drug molecules have only one pharmaceutically active enantiomer. Although it is always possible to force separation, it will come at a cost. The present method, based on thermodynamics, provides a relatively easy approach to investigate whether separation ...
Jezowski Sebastian R - - 2012
The anthracene cyclophane bis-anthracene (BA) can undergo a [4+4] photocycloaddition reaction that results in a photodimer with two cyclobutane rings. We find that the subsequent dissociation of the dimer, which involves the rupture of two carbon-carbon bonds, is strongly accelerated by the application of mild pressures. The reaction kinetics of ...
Thethi Tina - - 2012
Obesity is a risk factor for type 2 diabetes mellitus (DM) and is associated with chronic kidney disease. Activation of the renin-angiotensin-aldosterone system (RAAS) is common in obesity. The RAAS is an important mediator of hypertension. Mechanisms involved in activation of the RAAS in obesity include sympathetic stimulation, synthesis of ...
Doumas Michael - - 2012
Carotid baroreceptors play an important role in blood pressure regulation through modification of sympathetic nervous activity. Conditions associated with increased sympathetic activity, such as resistant hypertension and heart failure, represent potential targets for carotid baroreceptor activation. Recent technological advances made available a small device, like a pacemaker, that constantly activates ...
Pedersen Karsten - - 2012
Pressure-resistant circulating systems were constructed to enable the investigation of attached and unattached microbial populations under in situ pressure (2.5 MPa), diversity, dissolved gas, and chemistry conditions. Three parallel-flow cell cabinets were configured to allow observation of the effect on microbial metabolic activity of adding 3 mM hydrogen or 2.4 ...
Jarvandi S - - 2012
Aims  Vitamin D levels are inversely related to blood pressure. Given that low sun exposure can create a greater reliance on dietary sources of vitamin D, we aimed to determine whether dietary vitamin D and blood pressure associations differ between periods of low and high sun exposure. Methods  Dietary intake, ...
Roman S - - 2012
Background  Esophageal motility abnormalities include a series of manometric findings that differ to a significant degree from findings in normal, asymptomatic volunteers. Methods  Current review summarizes conventional and high-resolution esophageal manometry criteria used to define and characterize esophageal hypertensive motility abnormalities. Key Results  In the conventional esophageal manometry classification scheme ...
Colin Jérôme - - 2012
The morphological evolution by surface diffusion of a core-shell spherical particle has been investigated theoretically under hydrostatic pressure when the shear modulii of the core and shell are different. A linear stability analysis has demonstrated that depending on the pressure, shear modulii, and radii of both phases, the free surface ...
Gashev Anatoliy A - - 2012
Heterogeneity of the length-tension relationships in lymph vessels has never been evaluated systematically. In this study we measured the length-tension relationships in lymph vessels from three different regions of the rat: thoracic duct, cervical, and femoral lymph vessels, and compared the results to our previous measurements of rat mesenteric lymph ...
Rabochiy Pyotr - - 2012
We establish, via classical density functional theory, that the crossover to activated transport in liquids takes place when the depth of the metastable minimum in the free energy corresponding to long-lived aperiodic structures reaches a certain near universal value. We show that the particle vibrational displacement is strongly correlated with ...
Smit C A J - - 2012
Study design:Ten participants underwent two electrical stimulation (ES) protocols applied using a custom-made electrode garment with built-in electrodes. Interface pressure was measured using a force-sensitive area. In one protocol, both the gluteal and hamstring (g+h) muscles were activated, in the other gluteal (g) muscles only.Objectives:To study and compare the effects ...
Ceron Carla S - - 2012
Increased vascular matrix metalloproteinases (MMPs) levels play a role in late phases of hypertensive vascular remodeling. However, no previous study has examined the time course of MMPs in the various phases of two-kidney, one-clip hypertension (2K1C). We examined structural vascular changes, collagen and elastin content, vascular oxidative stress, and MMPs ...
Ford Rebecca J - - 2012
OBJECTIVES:: AMP-activated protein kinase (AMPK) activity may alter blood pressure by directly influencing vascular tone. The purpose of this study is to examine if these effects occur acutely in a model of hypertension. METHODS AND RESULTS:: Using distinct groups of Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) we compare ...
Campuzano Victoria - - 2012
A hallmark feature of Williams-Beuren Syndrome (WBS) is a generalized arteriopathy due to elastin deficiency, presenting as stenoses of medium and large arteries and leading to hypertension and other cardiovascular complications. Deletion of a functional NCF1 gene copy has been shown to protect a proportion of WBS patients against hypertension, ...
Yan Rongguo - - 2012
The computational fractal dimension of human colonic pressure activity acquired by a telemetric capsule robot under normal physiological conditions was studied using the box-counting method. The fractal dimension is a numeric value that quantifies to measure how rough the signal is from nonlinear dynamics, rather than its amplitude or other ...
Nesarikar Vishwas V - - 2012
Instrumented roll technology on Alexanderwerk(®) WP120 roller compactor was developed and utilized successfully for the measurement of normal stress on ribbon during the process. The effects of process parameters such as roll speed (4-12rpm), feed screw speed (19-53rpm), and hydraulic roll pressure (40-70bar) on normal stress and ribbon density were ...
Fu Jinxia - - 2012
Brominated flame retardants (BFRs) have been used in a variety of consumer products in the past four decades. The vapor pressures for three widely used BFRs, that is, tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD), and octabromodiphenyl ethers (octaBDEs) mixtures, were determined using the Knudsen effusion method and compared with those of ...
Gross Roxann Diez - - 2012
The purpose of this experiment was to confirm the presence of positive subglottic air pressure during swallowing, known as deglutitive subglottic air pressure (DPsub), in a group of healthy individuals. We also sought to determine if respiratory system recoil is responsible for generating the pressure. Ten healthy volunteers underwent direct ...
Deji Naoko - - 2012
Salt-sensitive hypertension is a characteristic of the metabolic syndrome. Given the links to cardiovascular events, the mechanisms underlying sodium metabolism may represent an important therapeutic target for this disorder. Angiotensin II (AII) is a key peptide underlying sodium retention. However, 5'AMP-activated protein kinase (AMPK) has also been reported to participate ...
Takeshita Telma Kioko - - 2012
BACKGROUND: The objective of the present study was to relate the dimensions and the intraluminal pressure of the pharyngoesophageal segment (PES) to the voice and speech proficiency of total laryngectomees with a tracheoesophageal prosthesis (TEP). METHODS: Twenty total laryngectomees with secondary TEP insertion underwent evaluation of voice and speech, manometry, ...
Extrand Charles William - - 2012
In this work, clusters of three or four spheres were used to examine intrusion pressure. Polytetrafluoroethylene (PTFE) or polyamide 66 (PA66) spheres were arranged horizontally to create a single pore. Liquid drops of water or ethylene glycol were gently introduced from above. If the spheres were too large, drops flowed ...
Yoo Do Guen - - 2012
It is essential to select the optimal pressure gauge location for effective management and maintenance of water distribution systems. This study proposes an objective and quantified standard for selecting the optimal pressure gauge location by defining the pressure change at other nodes as a result of demand change at a ...
Teran Enrique - - 2012
AIM: To investigate the effect of intravenous hydralazine infusion on maternal nitric oxide (NO) levels. METHODS: This pilot study comprised 40 (n = 40) gestations complicated with severe preeclampsia to whom maternal plasma NO levels were determined by chemiluminescence before and after hydralazine administration. Blood pressure values were concomitantly assessed. RESULTS: After ...
de Koker Nico - - 2012
Due to its large pressure range of stability and inert nature, cubic boron nitride has been proposed as a potential pressure standard for high pressure experiments. It is extremely refractive upon compression, although its melting temperature is not known beyond 10 GPa. We apply first-principles molecular dynamics to evaluate the thermodynamics ...
Smith Timothy W TW Department of Psychology, University of Utah, Salt Lake City, UT 84112, USA. - - 2012
Physiological effects of social evaluation are central in models of psychosocial influences on physical health. Experimental manipulations of evaluative threat evoke substantial cardiovascular and neuroendocrine responses in laboratory studies, but only preliminary evidence is available regarding naturally occurring evaluative threats in daily life. In such nonexperimental ambulatory studies, it is ...
Spooner J - - 2012
Experimentally, the effects of pressure on reaction rates are described by their pressure derivatives, known as volumes of activation. Transition state theory directly links activation volumes to partial molar volumes of reactants and transition states. We discuss a molecular dynamics method for the accurate calculation of molecular volumes, within which ...
Fedorowski Artur - - 2012
OBJECTIVE:: Although recent studies have indicated that both orthostatic hypotension and orthostatic hypertension (OHTN) independently predict cardiovascular events, the underlying mechanisms are still debatable. METHODS:: A total of 700 nondiabetic adults (43% men, age 64 years) were examined by orthostatic blood pressure (BP) test, carotid artery ultrasonography, and biochemical tests ...
Cheeney G - - 2012
Recto-anal inhibitory reflex (RAIR) is an integral part of normal defecation. The physiologic characteristics of RAIR along anal length and anterior-posterior axis are unknown. The aim of this study was to perform topographic and vector-graphic evaluation of RAIR along anal canal using high definition manometry (HDM), and examine the role ...
Gingrich Laura L - - 2012
PURPOSE: The present study investigated lingual propulsive pressures generated in the normal swallow by the anterior and posterior lingual segments for various consistencies and maximum isometric tasks. METHOD: Lingual pressures for saliva, thin, and honey-thick liquid boluses were measured via the Iowa Oral Performance Instrument (IOPI) at both anteromedian and ...
Malvè M - - 2012
A computational fluid dynamics model of a healthy, a stenotic and a post-operatory stented human trachea was developed to study the respiration under physiological boundary conditions. For this, outflow pressure waveforms were computed from patient-specific spirometries by means of a method that allows to compute the peripheral impedance of the ...
Braga Iracema Utsch - - 2012
This paper presents a method for prediction of forces and displacements in the expansion screw of a modified mandibular Schwarz appliance and the contact pressure distributions on the mucosa during malocclusions treatment. A 3D finite element biomechanical model of the complete mandible-mucosa-apparatus set was built using computerised tomographic images of ...
Katsogridakis Emmanuel - - 2012
The assessment of cerebral autoregulation (CA) relies mostly on methods that modulate arterial blood pressure (ABP). Despite advances, the gold standard of assessment remains elusive and clinical practicality is limited. We investigate a novel approach of assessing CA, consisting of the intermittent application of thigh cuffs using square wave sequences. ...
Scuteri Angelo - - 2012
Objectives.The aim of the present study was to investigate the prevalence of hypotension in older participants and to identify which 24-hour ambulatory blood pressure monitoring parameter better correlated with the occurrence of hypotension. METHODS: We studied 588 elderly participants (mean age 78.7 ± 7.1 years; 70% women) who underwent a ...
Climie Rachel E D - - 2012
BackgroundNoninvasive central blood pressure (BP) independently predicts mortality, but current methods are operator-dependent, requiring skill to obtain quality recordings. The aims of this study were first, to determine the validity of an automatic, upper arm oscillometric cuff method for estimating central BP (O(CBP)) by comparison with the noninvasive reference standard ...
Bai Bo - - 2012
We investigated the contact pressure and area of the patellofemoral joint both before and after different meniscectomies to provide a biomechanical basis for selecting meniscectomy and its clinical application for meniscus injuries. Six fresh cadaveric knees were used in the study. Using Staubli robots and an ultra-low-min-type pressure-sensitive tablet, changes ...
Zhu Li - - 2012
Oxygen is in many ways a unique element: It is the only known diatomic molecular magnet, and it exhibits an unusual O(8) cluster in its high-pressure solid phase. Pressure-induced molecular dissociation as one of the fundamental problems in physical sciences has been reported from theoretical or experimental studies of diatomic ...
Sørensen Mette - - 2012
Short-term exposure to air pollution has been associated with changes in blood pressure (BP) and emergency department visits for hypertension, but little is known about the effects of long-term exposure to traffic-related air pollution on BP and hypertension. We studied whether long-term exposure to air pollution is associated with BP ...
Andreadis Emmanuel A - - 2012
OBJECTIVE: To compare the quality and accuracy of morning blood pressure (BP) readings as taken by automated office BP (AOBP) and morning home BP (mHBP) techniques using morning ambulatory BP (mABP) measurements as the gold standard. METHODS: A total of 139 individuals were included, 70 men and 69 women, mean ...
Kato Masayuki - - 2012
Recently, endoscopic clip application devices have undergone redesign and improvements to optimize their clinical use and effectiveness. Initially designed for the treatment of bleeding nonvariceal lesions, these devices are also increasingly used for the closure of perforations, fistulas, and anastomotic leaks. Several clinical studies, both randomized and nonrandomized, have used ...
Lei Zhipeng - - 2012
This article presents a computational and experimental study of contact pressure between six N95 filtering facepiece respirators (FFRs) and five newly developed digital headforms (small, medium, large, long/narrow, and short/wide). Contact interaction is simulated using the finite element method and validated by experiments using a pressure mapping system. The headform ...
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