12,834 results match your criteria pressure drop


Effects of Trabecular Meshwork Width and Schlemm's Canal Area on Intraocular Pressure Reduction in Glaucoma Patients.

Korean J Ophthalmol 2021 Jun 21. Epub 2021 Jun 21.

Department of Ophthalmology, Korea University College of Medicine, Seoul, Republic of Korea.

Purpose: To evaluate the effects of baseline trabecular meshwork (TM) and Schlemm's canal (SC) microstructures on intraocular pressure (IOP) reduction amount in treatment-naïve patients with primary open-angle glaucoma (POAG).

Methods: A total 69 eyes of POAG patients who had not been treated with IOP-lowering agent were enrolled in this retrospective study. The patients had been prescribed topical IOP-lowering agent and used it for 1 year. Read More

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The effect of water on the large-scale supercritical fluid chromatography purification of two factor XIa active pharmaceutical ingredients.

J Chromatogr A 2021 Jun 4;1651:462318. Epub 2021 Jun 4.

Department of Discovery Synthesis, Bristol Myers Squibb Research and Early Development, Route 206 & Province Line Rd, Princeton, NJ 08543-4000, United States.

BMS-962212, a parenteral Factor XIa inhibitor, was scaled-up for toxicity studies. Two steps of supercritical fluid chromatography (SFC) were developed for the chiral resolution of the penultimate and achiral purification of final active pharmaceutical ingredient (API), BMS-962212. A robust SFC process using Chiralcel OD-H with methanol-acetonitrile as modifier in CO was established to achieve a stable and uninterrupted operation with reduced mobile phase viscosity and system pressure drop. Read More

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Theoretical study of the efficiency of liquid chromatography columns with particle size gradient.

J Chromatogr A 2021 Jun 9;1651:462331. Epub 2021 Jun 9.

Research Group of Analytical Chemistry, University of Pannonia, Egyetem utca 10, Veszprém H-8200, Hungary.

Modern analytical applications of liquid chromatography require more and more efficient columns. In this work, the possibility of utilizing particle size gradient in the chromatographic column was studied by a theoretical approach. In the course of our work three different scenarios of particle size gradients were considered with different shapes (linear, convex and concave). Read More

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Left Ventricular Pressure Ratio Predicts In-Hospital Outcomes in Hospitalized Heart Failure With Reduced Ejection Fraction.

J Invasive Cardiol 2021 Jun 16. Epub 2021 Jun 16.

Section of Cardiology, Department of Medicine, The University of Chicago Medicine, 5841 South Maryland, M-547, MC 5076, Chicago, IL 60637 USA.

Background: Given the risk of hemodynamic compromise in heart failure with reduced ejection fraction (HFrEF) patients undergoing left heart catheterization (LHC), there is a need for a simple parameter that can predict clinical outcomes. We hypothesize that left ventricular pressure ratio (LVPR), calculated as left ventricle systolic/left ventricle end-diastolic pressure, is a strong predictor of hemodynamic collapse in these patients.

Methods: Retrospective analysis of consecutive hospitalized HFrEF patients undergoing combined LHC and right heart catheterization (RHC) at a single institution from 2015-2017 was performed. Read More

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Pro Re Nata Antihypertensive Medications and Adverse Outcomes in Hospitalized Patients: A Propensity-Matched Cohort Study.

Hypertension 2021 Jun 21:HYPERTENSIONAHA12117279. Epub 2021 Jun 21.

Division of Nephrology, Hypertension and Transplantation, University of Florida, Gainesville (R.M., G.C., S.B., J.C., T.O.-B., R.R., A.S., A.K., A.B., M.C., M.S.S.).

Physicians routinely order blood pressure (BP) medications on an as needed basis or pro re nata to control BPs in hospitalized patients. We hypothesized that treatment of inpatients, who do not have a hypertensive emergency, with the use of antihypertensive medication on an as needed basis could lead to adverse outcomes. Four thousand two hundred nineteen patients who received BP medications on an as needed basis in addition to scheduled antihypertensive medications were matched 1:1 using propensity matching to those who received only scheduled BP medications. Read More

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Pressure monitoring devices may undetect epidural space: a report on the use of Compuflo® system for epidural injection.

J Clin Monit Comput 2021 Jun 20. Epub 2021 Jun 20.

Unit of Anaesthesia, Intensive Care and Pain Management, Department of Medicine, Università Campus Bio-Medico di Roma, via Álvaro del Portillo 21, 00128, Rome, Italy.

Lumbar epidural infiltration (EI) is a feasible procedure performed in pain therapy. Even though epidural analgesia is widely applied, it remains a blind technique, based on the operator's hand sensations, and it is associated with significant failure rate and several potential complications. Compuflo® (Compuflo, Milestone Scientific, Livingston, NJ) is a computerized injection pump which precisely detects the real time pressure at the tip of a Tuohy needle when placed in human tissues, thanks to a continuous fluid path. Read More

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Alveolar Recruitment Maneuver Reduces Cerebral Oxygen Saturation and Cerebral Blood Flow Velocity in Patients During Carotid Endarterectomy.

Med Sci Monit 2021 Jun 20;27:e930617. Epub 2021 Jun 20.

Department of Anesthesiology, Xuanwu Hospital, Capital Medical University, Beijing, China (mainland).

BACKGROUND This study aimed to determine the effects of alveolar recruitment maneuver (RM) on cerebral oxygen saturation and cerebral blood velocity in patients undergoing carotid endarterectomy (CEA) before clamping of the carotid artery. MATERIAL AND METHODS In this crossover exploratory study, all patients were randomized to undergo an RM (30 cmH₂O of continuous airway pressure for 30 s) and a "sham" maneuver (SM; 5 cmH₂O for 30 s), followed by an alternative intervention after a 5-min equilibration period. Near-infrared spectroscopy (NIRS) was used to monitor regional cerebral oxygen saturation (rSO₂), and transcranial Doppler ultrasonography (TCD) to evaluate blood velocity of the middle cerebral artery (V-MCA). Read More

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Review of ultrasound combinations with hybrid and innovative techniques for extraction and processing of food and natural products.

Ultrason Sonochem 2021 Jun 11;76:105625. Epub 2021 Jun 11.

Avignon University, INRAE, UMR408, GREEN Extraction Team, 84000 Avignon, France. Electronic address:

Ultrasound has a significant effect on the rate of various processes in food, perfume, cosmetic, pharmaceutical, bio-fuel, materials, or fine chemical industries, despite some shortcomings. Combination with other conventional or innovative techniques can overcome these limitations, enhance energy, momentum and mass transfer, and has been successfully demonstrated in many recent studies. Various ultrasound combined hybrid and innovative techniques are systematically summarized in this review for the first time. Read More

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Percutaneous closure of a patent foramen ovale causing exercise hypoxemia: Case report and a review of the literature.

Catheter Cardiovasc Interv 2021 Jun 19. Epub 2021 Jun 19.

Department of Cardiology and Intensive Care, Klinikum Wels-Grieskirchen, Wels, Austria.

Provoked exercise desaturation is a rare presentation of patent foramen ovale (PFO), when vigorous exercise leads to desaturation of arterial blood and subsequent dyspnea. We present a case of provoked exercise desaturation and curative percutaneous closure and review the literature. A 54-year-old male patient presented with shortness of breath during exercise in the pneumology outpatient department. Read More

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Personalized Pre- and Post-Operative Hemodynamic Assessment of Aortic Coarctation from 3D Rotational Angiography.

Cardiovasc Eng Technol 2021 Jun 18. Epub 2021 Jun 18.

Digital Services, Digital Technology & Innovation, Siemens Healthineers, 755 College Road, Princeton, NJ, 08540, USA.

Purpose: Coarctation of Aorta (CoA) is a congenital disease consisting of a narrowing that obstructs the systemic blood flow. This proof-of-concept study aimed to develop a framework for automatically and robustly personalizing aortic hemodynamic computations for the assessment of pre- and post-intervention CoA patients from 3D rotational angiography (3DRA) data.

Methods: We propose a framework that combines hemodynamic modelling and machine learning (ML) based techniques, and rely on 3DRA data for non-invasive pressure computation in CoA patients. Read More

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The effects of caffeine in adults with neurogenic orthostatic hypotension: a systematic review.

Clin Auton Res 2021 Jun 18. Epub 2021 Jun 18.

Population Health Sciences Institute, Newcastle University, Newcastle Upon Tyne, UK.

Purpose: To systematically review the evidence base for the effectiveness and safety of caffeine for the treatment of neurogenic orthostatic hypotension in adults.

Methods: Eight electronic databases were searched in January 2021. Original research studies or case reports involving adults with neurogenic orthostatic hypotension were included if caffeine was an intervention and outcomes included symptoms, blood pressure or adverse effects. Read More

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Thoracoscopic diagnosis of traumatic pericardial rupture with cardiac hernia: A case report.

World J Clin Cases 2021 Jun;9(16):4001-4006

Department of General Surgery, Tongde Hospital of Zhejiang Province, Hangzhou 310000, Zhejiang Province, China.

Background: Pericardial rupture caused by blunt chest trauma is rare in clinical practice. Because of its atypical clinical symptoms, and because surgeons are often unfamiliar with the clinical and radiological manifestations of the injury, preoperative diagnosis is difficult; it is easily misdiagnosed and causes serious consequences.

Case Summary: A 60-year-old man, previously healthy, was transported to the emergency room after falling from a great height. Read More

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[Single center retrospective study of catheter directed thrombolysis in patients with acute pulmonary embolism].

Medicina (B Aires) 2021 ;81(3):382-388

Servicio de Hemodinamia y Cardiología Intervencionista, Instituto de Medicina Cardiovascular, Hospital Italiano de Buenos Aires, Argentina.

We performed a single center retrospective study in patients wi th pulmonary embolism (PE) undergoing catheter directed thrombolysis (CDT) from 2014 to 2020. Efficacy was defined by mean pulmonary pressure drop, and safety was assessed by intracranial and severe bleeding (defined by GUSTO). Forty-three patients were included, aged 64 (56-79) years old, 5 (12%) with shock, most with right ventricle dilation (95%) and bilateral PE (95%) or unilateral (5%) in patients with only one functional lung. Read More

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Potential for Behavioural Pressure Modulation at the Upper Oesophageal Sphincter in Healthy Swallowing.

Dysphagia 2021 Jun 16. Epub 2021 Jun 16.

Department of Psychology, Speech and Hearing, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand.

Supratentorial structures are known to be involved in the neural control of swallowing, thus the potential for volitional manipulation of pharyngeal swallowing is of rehabilitative interest. The extent of volitional control of the upper oesophageal sphincter (UOS) during swallowing remains unclear. Prior research has shown that the UOS opening duration can be volitionally prolonged during execution of the Mendelsohn manoeuvre, which does not change the UOS opening time in isolation but the swallowing response in its entirety. Read More

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Discrete fracture network model analysis of the effects of fluid transport on the morphology of a cluster of activated fractures.

Phys Rev E 2021 May;103(5-1):053112

Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.

Convective transport in low-permeability rocks can be enhanced by the injection of a pressurized fluid to activate preexisting weak planes (fractures). These fractures are initially closed, but fluid-pressure-induced slippage creates void space that allows for fluid flow. The Coulomb-Mohr criterion yields a critical pressure required to open each of the fractures. Read More

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Methane Hydrate Crystallization on Sessile Water Droplets.

J Vis Exp 2021 May 26(171). Epub 2021 May 26.

Earth and Atmospheric Sciences, Georgia Institute of Technology;

This paper describes a method to form methane hydrate shells on water droplets. In addition, it provides blueprints for a pressure cell rated to 10 MPa working pressure, containing a stage for sessile droplets, a sapphire window for visualization, and temperature and pressure transducers. A pressure pump connected to a methane gas cylinder is used to pressurize the cell to 5 MPa. Read More

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Improving aeration systems in saline water (part II): effect of different salts and diffuser type on oxygen transfer of fine-bubble aeration systems.

Water Sci Technol 2021 Jun;83(11):2778-2792

Technical University of Darmstadt, Institut IWAR, Franziska-Braun-Str. 7, 64287 Darmstadt, Germany E-mail:

The objective of the present study is to investigate the different effects on the oxygen transfer of fine-bubble aeration systems in saline water. Compared to tap water, oxygen transfer increases due to the inhibition of bubble coalescence. In Part I of the present study, we investigated in laboratory-scale experiments the effect of design of diffuser membrane. Read More

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Determining the Dependence of Interfacial Tension on Molecular Area for Phospholipid Monolayers Formed at Silicone Oil-Water and Tricaprylin-Water Interfaces by Vesicle Fusion.

Langmuir 2021 06 11;37(24):7527-7535. Epub 2021 Jun 11.

Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.

Phospholipid monolayers formed at oil-water interfaces have been used to explore biological interface properties. Thus, monolayer systems need to be quantitatively understood. Previously, we investigated the formation of 1-palmitoyl-2-oleoyl--glycero-3-phosphocholine (POPC) monolayers at silicone oil-water interfaces to determine the dependence of interfacial tension, γ, on the area per lipid, , compared to that of the closely packed monolayers, . Read More

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Effects of Layering and Supporting Substrate on Liquid Slip at the Single-Layer Graphene Interface.

ACS Nano 2021 Jun 11;15(6):10095-10106. Epub 2021 Jun 11.

Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Matthews Avenue, Urbana, Illinois 61801, United States.

Understanding modulation of liquid molecule slippage along graphene surfaces is crucial for many promising applications of two-dimensional materials, such as in sensors, nanofluidic devices, and biological systems. Here, we use force measurements by atomic force microscopy (AFM) to directly measure hydrodynamic, solvation, and frictional forces along the graphene plane in seven liquids. The results show that the greater slip lengths correlate with the interfacial ordering of the liquid molecules, which suggests that the ordering of the liquid forming multiple layers promotes slip. Read More

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Prophylactic effect of brinzolamide-brimonidine fixed combination on intraocular pressure spikes after intravitreal anti-VEGF injections.

Int Ophthalmol 2021 Jun 10. Epub 2021 Jun 10.

Department of Ophthalmology, "Elpis" General Hospital of Athens, 7 Dimitsanas Street, 115 22, Athens, Greece.

Purpose: To evaluate the effect of topical prophylaxis with brinzolamide-brimonidine fixed combination on short-term intraocular pressure (IOP) elevation after intravitreal injections of anti-vascular endothelial growth factors (anti-VEGF).

Methods: This prospective comparative study included 56 eyes of 47 patients treated with intravitreal injections of anti-VEGF, and they were randomly divided into two groups. In control group (25 eyes), no prophylactic medication was used, whereas in case group (31 eyes) one drop of a fixed combination of brinzolamide-brimonidine was instilled two hours before the injection. Read More

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Association Between Aneurysmal Haemodynamics and Device Microstructural Characteristics After Flow-Diversion Treatments With Dual Stents of Different Sizes: A Numerical Study.

Front Physiol 2021 25;12:663668. Epub 2021 May 25.

Biomedical Flow Dynamics Laboratory, Institute of Fluid Science, Tohoku University, Sendai, Japan.

Objectives: Treating intracranial aneurysms with flow-diverting stents sometimes requires deployment of a second device. Herein we quantify the sizing effects of devices in dual-stent treatments upon the final stent microstructure and the post-treatment aneurysmal haemodynamics.

Methods: Fifteen sidewall ICA aneurysm geometries were included. Read More

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A randomized clinical trial using cyclopentolate and tropicamide to compare cycloplegic refraction in Chinese young adults with dark irises.

BMC Ophthalmol 2021 Jun 10;21(1):256. Epub 2021 Jun 10.

Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 251 Fukang Road, Nankai District, Tianjin, China.

Background: To evaluate the necessity of cycloplegia for epidemiological studies of refraction in Chinese young adults (aged 17-22 years) with dark irises, and to compare the cycloplegic effects of 1% cyclopentolate and 0.5% tropicamide in them.

Methods: A total of 300 young adults (108 males and 192 females) aged 17 to 22 years (mean 19. Read More

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Muscle Loss is Associated with Risk of Orthostatic Hypotension in Older Men and Women.

J Frailty Aging 2021 ;10(3):219-225

Melissa J. Benton, PhD, RN, Helen and Arthur E. Johnson Beth-El College of Nursing and Health Sciences, University of Colorado Colorado Springs, 1420 Austin Bluffs Parkway, Colorado Springs, CO 80918, phone: +1-719-255-4140, email:

Background: Muscle provides a reservoir for water to maintain fluid volume and blood pressure, so older adults may be at risk for orthostatic hypotension due to muscle loss with age.

Objectives: To evaluate the association between muscle loss with age and postural blood pressure.

Design: Longitudinal comparison of overnight changes in hydration, postural blood pressure, and strength. Read More

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Optical Flow Ratio for Assessing Stenting Result and Physiological Significance of Residual Disease.

EuroIntervention 2021 Jun 8. Epub 2021 Jun 8.

Biomedical Instrument Institute, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.

Background: Optical flow ratio (OFR) is a novel method for fast computation of fractional flow reserve (FFR) from optical coherence tomography (OCT) images.

Aims: We aimed to evaluate the accuracy of OFR in predicting post-percutaneous coronary intervention (PCI) FFR and to evaluate the impact of stent expansion on within-stent OFR pressure drop (In-stent OFR).

Methods: Post-PCI OFR was computed in patients with both OCT and FFR interrogation immediately after PCI. Read More

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Health protective regulation of the fashion industry

Orv Hetil 2021 06 6;162(23):905-910. Epub 2021 Jun 6.

3 Semmelweis Egyetem, Általános Orvostudományi Kar, I. Gyermekgyógyászati Klinika, Budapest.

Összefoglaló. A divatiparra vonatkozó egészségvédelmi szabályozások hiányosak. A karcsúság elérését célzó szociokulturális nyomás a divatiparon belül fokozott, a divatmodelleket gyakran késztetik kórosan alacsony testsúly elérésére, ami pszichológiai abúzusnak felel meg. Read More

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Diabetic diarrhoea: a study on gastrointestinal motility, pH levels and autonomic function.

J Intern Med 2021 Jun 5. Epub 2021 Jun 5.

Department of Medicine, Haukeland University Hospital, Bergen, Norway.

Background: Chronic diarrhoea is a common, but poorly investigated diabetes complication. Autonomic neuropathy is a leading pathophysiological theory founded on old, small studies. Studies of gastrointestinal motility and pH levels are lacking. Read More

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Facile strategy to prepare polyimide nanofiber assembled aerogel for effective airborne particles filtration.

J Hazard Mater 2021 Aug 24;415:125739. Epub 2021 Mar 24.

College of Materials Science and Engineering, Donghua University, Shanghai 201620, People's Republic of China; State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620, People's Republic of China. Electronic address:

Polyimide nanofiber (PINF) aerogel materials have received extensive attention as heat insulation, sensors and filtration media due to their excellent thermodynamic properties and unique porous structure. However, PINF must be difficult to disperse in organic solvents (dioxane or dimethyl sulfoxide) and dimensional instability has been regarded as issues that limits the preparation of PINF aerogels, especially in the water. So, it is of great significance to prepare polyimide aerogels with stable structure using water as a dispersant. Read More

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Molecular diffusion analysis of dynamic blood flow and plasma separation driven by self-powered microfluidic devices.

Biomicrofluidics 2021 May 21;15(3):034106. Epub 2021 May 21.

Department of Physics, North Dakota State University, Fargo, North Dakota 58108, USA.

Integration of microfluidic devices with pressure-driven, self-powered fluid flow propulsion methods has provided a very effective solution for on-chip, droplet blood testing applications. However, precise understanding of the physical process governing fluid dynamics in polydimethylsiloxane (PDMS)-based microfluidic devices remains unclear. Here, we propose a pressure-driven diffusion model using Fick's law and the ideal gas law, the results of which agree well with the experimental fluid dynamics observed in our vacuum pocket-assisted, self-powered microfluidic devices. Read More

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Scale-up of reverse electrodialysis for energy generation from high concentration salinity gradients.

J Memb Sci 2021 Jun;627:119245

Cranfield Water Science Institute, Cranfield University, Bedfordshire, MK43 0AL, UK.

Whilst reverse electrodialysis (RED) has been extensively characterised for saline gradient energy from seawater/river water (0.5 M/0.02 M), less is known about RED stack design for high concentration salinity gradients (4 M/0. Read More

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Feasibility and postoperative opioid sparing effect of an opioid-free anaesthesia in adult cardiac surgery: a retrospective study.

BMC Anesthesiol 2021 Jun 3;21(1):166. Epub 2021 Jun 3.

CHU Bordeaux, Department of Anaesthesia and Critical Care, Magellan Medico-Surgical Centre, F-33000, Bordeaux, France.

Background: No previous study investigated the dexmedetomidine-based opioid-free anesthesia (OFA) protocol in cardiac surgery. The main objective of this study was to evaluate the feasibility and the postoperative opioid-sparing effect of dexmedetomidine-based OFA in adult cardiac surgery patients.

Methods: We conducted a single-centre and retrospective study including 80 patients above 18 years old who underwent on-pump cardiac surgery between November 2018 and February 2020. Read More

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