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Buchel H B - - 1990
The pressurized gas transport which improves the oxygen supply of the roots of the wetland tree black alder (Alnus glutinosa (L.) Gaertn.), is based on the existence of a thermo-osmotically active porous tissue partition in the lower part of the trunk with pore diameters in the range of, or smaller ...
Adams D S - - 1990
We have examined the biomechanical development of the notochord of Xenopus early tail-bud embryos by: (1) quantifying morphological and mechanical changes in the embryo during stages 20-28, and (2) conducting manipulative experiments to elucidate mechanical roles of various components of the notochord. The notochord, which is composed of a stack ...
Bungum L - - 1990
During the puerperium significant changes occur in the body volume homeostasis. In the present study the transcapillary fluid balance was examined antepartum in nine healthy women. The interstitial colloid osmotic pressure was measured by the 'wick' method, and interstitial hydrostatic pressure by the 'wick-in-needle' method in subcutaneous tissue on the ...
Robertson B C - - 1990
The authors have developed a comprehensive mathematical model of the hemodialysis process to investigate the effect of r-HuEPO and the accompanying higher hematocrit on backfiltration in high flux dialysis. Model simulations indicate that under otherwise identical conditions typical of high flux dialysis, an increase in hematocrit from 20 to 33% ...
Ward D M - - 1990
Hydrostatic synovial fluid pressure within the superior aspect of the temporomandibular joint space of the growing pig, Sus scrofa domesticus, was examined in response to various acute and chronic alterations of mandibular position. Bilateral measurements of pressure were recorded with chronically implanted wick catheters in three 8-week-old pigs before and ...
Takeuchi S - - 1990
The pressure lowering effect of glycerol and mannitol on the interstitial fluid pressure of the facial nerve was studied in normal guinea pigs. The effect of low-molecular dextran on the interstitial fluid pressure of the facial nerve was also studied. Both peroral administration of glycerol and intravenous administration of mannitol ...
Hahn R G - - 1990
Signs and symptoms, circulatory changes and the diffusion of fluid and electrolytes were examined over 10-min periods in the course of 12 transurethral resections of the prostate (TURP) during which more than 1 litre of glycine solution was absorbed. Signs of the TURP syndrome were seen in 10 patients. During ...
Booth I R - - 1990
Enteric bacteria have evolved an impressive array of mechanisms that allow the cell to grow at widely different external osmotic pressures. These serve two linked functions; firstly, they allow the cell to maintain a relatively constant turgor pressure which is essential for cell growth; and secondly they permit changes in ...
Rols M P - - 1990
Cells can be transiently permeabilized by application of high electric pulses of short duration. A direct consequence of this treatment is to induce a fusogenic state in the pulsed membrane. The molecular events underlying these phenomena remain to be explained. During our work, we investigated the effects of pulsing buffer ...
Seem E - - 1990
Interstitial fluid pressure (Pif), plasma- and interstitial fluid colloid osmotic pressures (COPpl, COPif) were measured in muscle compartments of the calf in lower limbs of patients with deep venous thrombosis (DVT) and in contralateral limbs. Pif was measured with the 'wick-in-needle' technique in the anterior and deep posterior compartments in ...
McDonald J N - - 1990
The ease with which fluid passes across the synovial lining (i.e., the lining's hydraulic conductance) is enhanced when intraarticular fluid pressure (IAP) is raised acutely to pathological levels in rabbit knees. A structural basis for this pathophysiological change was sought by morphometry of synovial sections from rabbit knees fixed in ...
Gilányi M - - 1990
Inherent problems concerning the interstitial fluid pressure (IFP) are reinvestigated on theoretical grounds. Analyzing the thermodynamic and mechanical equilibria in the interstitium, it is concluded that IFP includes a pressure term originating from the elastic forces and an osmotic pressure term. A quantitative relationship is established between the IFP and ...
McKie A T - - 1990
The hydrostatic pressure required to reduce the water content of rabbit feces in an odometer from greater than 80 to less than 65% was approximately 5 atm. This pressure was unaffected by raising the temperature from 20 to 37 degrees C. It became progressively more difficult to dehydrate feces as ...
Tollan A - - 1990
Transcapillary fluid dynamics were studied in 10 women during ovarian stimulation for in vitro fertilization. The examinations were done on the first day of stimulation (day 3 of the menstrual cycle, mean serum estradiol concentration 0.2 nmol/L), and the day before oocyte aspiration (day 10 to 12, mean serum estradiol ...
Giesecke A H AH - - 1990
Fluid management of the traumatized patient begins with assessment of volume status via palpation of pulses; evaluation of mental status; and measurement of urine output, arterial blood pressure, and central pressures. Intravascular line placement and choice of initial resuscitation fluids should be individualized to the clinical situation, although in most ...
Iida N - - 1990
Flow autoregulation in the arteriolar network serves to maintain the capillary-tissue fluid balance by regulation of capillary pressure. In the present study, we have examined theoretically the effects of arteriolar vasomotion and venous pressure elevation on the capillary fluid exchange, the interstitial fluid pressure, and the interstitial osmotic pressure during ...
Nagashima T - - 1990
A two-dimensional model of vasogenic brain edema was constructed using the FEM. The model incorporates the following physical parameters: cerebrovascular hydraulic conductivity, metabolic water production, tissue hydraulic conductivity and compliance, tissue and plasma osmotic and hydrostatic pressures, CSF hydrostatic pressure and absorption, intracerebral stress, and shift of brain tissue. These ...
Hatashita S - - 1990
We studied how the osmotic pressure gradient between blood and the brain is related to the development of ischemic brain edema. Focal cerebral ischemia was produced by left MCA occlusion in rats. Brain osmolality was determined with a vapor pressure osmometer, water content of the brain tissue was measured by ...
Kuroiwa T - - 1990
The role of hydrostatic pressure and osmotic pressure gradient in the development of vasogenic brain edema induced by cold lesion made in the parietal cortex was studied in cats under ketamine anesthesia and blood pressure monitoring. The animals were divided into a hypertensive group and a normotensive group and were ...
Sirovskiy E E N.N. Burdenko Research Institute of Neurosurgery, Moskow, - - 1990
Monitoring of VFP and local brain interstitial fluid pressure was performed in 169 patients after removal of hemispheric gliomas, basal and subtentorial tumours. On the basis of CT-data 97% of the patients had postoperative oedema of various severity and spreading. The location of the tumour determined both the degree and ...
Wiig H - - 1990
As one of the determinants of net transcapillary filtration, filling of initial lymphatics and interstitial compliance, interstitial fluid pressure (Pi) is of great physiological interest. Several methods have been developed to measure Pi, all measuring the fluid equilibration pressure, i.e., the pressure in a saline-filled tube brought into contact with ...
Ogilvie-Harris D J - - 1990
We studied 25 patients who underwent an arthroscopic examination of the shoulder and in whom 20 had an arthroscopic acromioplasty. In all patients there was extravasation of fluid due to the use of pressure irrigation. The pressures rose from a baseline of 12 mm up as high as 120 mm ...
Levick J R - - 1989
1. The hydraulic conductance of the synovial lining of a rabbit knee increases greatly when intra-articular pressure (IAP) is raised above approximately 9 cmH2O (yield point). To investigate the cause, synovium was fixed in situ by perfusion at controlled IAP and prepared for transmission electron microscopy. Micrographs of synovium fixed ...
Bignall S - - 1989
We determined the oncotic and cardiovascular effects of a standardised infusion of human albumin (1.2 g/kg over 2 h as a 20% solution) in 12 premature infants on 18 occasions when hypovolaemia was suspected on clinical grounds. Blood volume increased by a median value of 15.5%, and fell to preinfusion ...
Duff D W - - 1989
Plasma oncotic pressure (OC), protein concentration (P), osmolality (Osm), and hematocrit (Hct) were measured in conscious rainbow trout subjected to 120 min of constant-pressure (CPH) or constant-volume (CVH) hemorrhage. Blood volume, tissue red cell, and plasma space were determined in control and CPH trout with 51Cr-labeled red cells and 125I-albumin. ...
Wiig H - - 1989
Interstitial fluid pressure (Pi) has been measured in vivo in ocular tissues of rats and rabbits, and in vitro in corneas of cows and humans with micropipettes connected to a servocontrolled counterpressure system. The in vivo measurements were performed after anaesthesia and careful immobilization of the head. In all species ...
Bokman E - - 1989
Two sets of experiments were made to determine if bis(tri-n-butyl)tin oxide (TBT) [IUPAC: hexabutyldistannoxane] influenced osmotic pressure or chloride ion concentration in hemolymph of adult American oysters, Crassostrea virginica. In the first set, oysters were acclimated to 5, 25 or 40%;, then exposed to bis(tri-n-butyl)tin oxide dissolved in seawater (0.5, ...
Edwards G L - - 1989
The region surrounding the anteroventral third ventricle, particularly the median preoptic nucleus, has been implicated in the control of fluid balance and blood pressure. Previous studies indicate that catecholaminergic inputs from the caudal medulla are important in these controls. In this study we report that neuropeptide Y-immunoreactive cells in the ...
Heyeraas K J - - 1989
The net rate of fluid movement across the microvascular endothelium is governed by hydrostatic and protein osmotic pressures operating on each side of the vessel wall. These basic forces regulating the pulpal transmicrovascular fluid exchange are the same as in other tissues. However, the pulp is special in regard to ...
Weber J - - 1989
Isolated nematocysts (capsules of stinging cells in Cnidaria) from the freshwater polyp Hydra vulgaris [Weber, J., Klug, M. & Tardent, P. (1987) Comp. Biochem. Physiol. 88B, 855-862] are under a constant internal osmotic pressure of 12.5 MPa. The capsular wall which withstands this considerable pressure has an average elasticity modulus ...
Böck J C - - 1989
The aim of this study was to define the post-traumatic changes in body fluid compartments and to evaluate the effect of plasma colloid osmotic pressure (COP) on the partitioning of body fluid between these compartments. Forty-two measurements of plasma volume (green dye), extracellular volume (bromine), and total body water (deuterium) ...
Rabbany S Y - - 1989
Previous measurements of intramyocardial pressure (IMP) have yielded systolic pressures that range from values lower than to far exceeding systolic left ventricular pressure (LVP). This study identifies a possible mechanism underlying these divergent observations by building on established morphology of the ventricular wall. It is hypothesized here that the generation ...
Taylor A - - 1989
Recently developed techniques have been used to reinvestigate the mechanism by which gibberellic acid (GA(3)) stimulates elongation of light-grown cucumber (Cucumis sativus L.) seedlings. Osmotic pressure and turgor pressure were slightly reduced in GA(3)-treated seedlings, which elongated 3.5 times faster than control seedlings. This indicated that GA(3) enhancement of growth ...
Miki K - - 1989
Water immersion (WI) causes an increase in plasma volume in humans and dogs. To determine the mechanism for this fluid movement, the transmission of external water hydrostatic pressure to the interstitial and vascular compartments was studied in six conscious dogs. Systemic arterial, central venous, peripheral arterial (ulnar artery) and venous ...
Joles J A - - 1989
Colloid osmotic pressure (COP) was measured in plasma and interstitial fluid (subcutaneous wick) from 8 to 75 days of age in Nagase analbuminemic rats (NAR) and control Sprague-Dawley rats (SDR). In all animals plasma COP (approximately 10 mmHg at 8 days of age) increased during growth. In the female NAR ...
Mortillaro N A - - 1989
Steady-state fluid pressure measurements were obtained from polyethylene capsules chronically implanted in the walls of cat ileum. Measurements were performed while ileal venous outflow pressure was maintained at 0, 10, 20, or 30 mmHg. The resulting mean steady-state capsule pressure ranged from -0.56 to 7.3 mmHg over the range of ...
Harilainen A - - 1989
In 10 patients referred to arthroscopy with traumatic effusions of the knee, the protein concentration of the synovial fluid (SF) correlated to its colloid osmotic pressure (pi SF). The pi SF did not correlate to the poorly determined hydrostatic pressure (PSF) in extended or slightly flexed joints or to the ...
Luckett P M - - 1989
Hydraulic conductivity (Lp) of endothelial cell monolayers cultured on a supporting matrix of human amnion was measured. Bovine aortic (Baec), bovine microvascular (Bmec), and human umbilical vein endothelial cell (Huvec) monolayers were mounted in a water-jacketed chamber maintained at 37 degrees C. The lower compartment of the chamber was connected ...
Länne T - - 1989
High levels (110-120 cmH2O) of lower body negative pressure (LBNP) were used in male volunteers (n = 7) to produce pronounced hypovolaemic circulatory stress in an attempt to reveal the potential in man for compensatory absorption of extravascular fluid from skeletal muscle and skin as studied in the upper arm ...
Haynes G R - - 1989
One useful but underused parameter of fluid replacement is colloid oncotic pressure. Colloid oncotic pressure (COP) is one of the Starling forces that maintain a balance between intravascular and extravascular fluid. Systemic and pulmonary circulations exhibit differences that limit the usefulness of COP manipulation in the treatment of pulmonary edema, ...
Zikria B A - - 1989
In this preliminary report, the capillary leakage that occurs after scald injury is considered a biophysical phenomenon and is treated by sealing the "pores," or endothelial gaps, in the capillary membranes with biodegradable macromolecules of the appropriate size and shape. We have measured albumin leakage from standardized scald burns in ...
Rackow E C - - 1989
Twenty consecutive patients with severe sepsis were randomized to fluid challenge with 5% albumin or 10% low MW hydroxyethyl starch (pentastarch) solutions. Fluid challenge was administered iv as 250 ml of test colloid every 15 min until the pulmonary artery wedge pressure (WP) was greater than or equal to 15 ...
Kaieda R - - 1989
The cerebral effects of alterations in plasma osmolality (Osm) and colloid oncotic pressure (COP) were examined in normocarbic, normothermic, pentobarbital-anesthetized rabbits that had been subjected to cryogenic brain injury. Monitored variables in all animals included mean arterial, right atrial, and intracranial pressures (MAP, CVP, and ICP), electroencephalographic (EEG) recordings, and ...
Kiil F - - 1989
Osmosis across a semipermeable membrane is usually treated in terms of thermodynamics, but the equations for osmosis can also be derived from kinetic considerations. Since fewer solvent molecules bombard the semipermeable membrane from the solution side, a kinetic pressure difference (osmotic potential) is generated into pore openings. Intermolecular forces cancel ...
Lund T - - 1989
We have measured tissue pressures in excised rat skin subjected to in vitro burn injury and investigated the mechanisms behind the increased imbibition (swelling) pressure in burned skin. Skin pieces wrapped in aluminum paper were immersed into boiling hot water for 10, 30, or 60 s. Dermal imbibition pressure was ...
Chiodera P - - 1989
In order to evaluate the possible influence of GABAergic neurotransmission on the arginine vasopressin (AVP) response to osmotic and pressure volumetric stimuli, the GABAergic drug sodium valproate was administered by mouth (200 or 400 mg 16 h, 8 h and just before tests) to eight normal men before osmotic (i.v. ...
Blake T R - - 1989
A theoretical description of the mechanics of the interstitium is used to derive a relation for interstitial fluid pressure. The nature of this relation is examined and the dependence of fluid pressure on imbibed fluid, free fluid, and osmotic balances is defined. When the theory is applied to an idealized ...
Hara M - - 1989
This study focused on the morphological alteration of the mucous membrane of the middle ear after transtympanic infusion of fluids with different osmotic pressure. Our results suggested that fluids with high osmotic pressure will seriously damage the mucous membrane of the middle ear regardless of whether or not the fluids ...
Zadrobilek E - - 1989
We investigated the effect of large volume replacement with balanced electrolyte solutions on extravascular lung water (EVLW) in 16 adult surgical patients with sepsis syndrome. Patients entered the study within the 24 h period following surgical interventions for acute necrotizing pancreatitis, intra-abdominal abscesses, and/or peritonitis. Sequential measurements (n = 108) ...
Rein K A - - 1989
Clinical observation and calculation of fluid balance have shown that patients undergoing aortocoronary bypass surgery with thoracic epidural analgesia (TEA) in addition to general anesthesia retain less fluid than patients having general anesthesia only. The present study was designed to investigate whether this effect could be explained by thoracic epidural ...
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