Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Capillary Action”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1993

Evaluating hypotheses for the transfer of stimulus particles to Jacobson's organ in snakes.

Six hypotheses for transfer mechanisms to the sensory epithelium of Jacobson's organ are presented: diffusion, capillary action, ciliary currents, pinocytotic currents, direct tongue insertion, and suction. Of these, diffusion and capillary action are rejected on theoretical grounds, and ciliary and pinocytic currents are seen as playing, at best, a secondary role. Of the two remaining hypotheses, direct insertion of the tongue and suction, experimental evidence is summarized that leads to the rejection of the direct insertion hypothesis. The stimulus transfer mechanism is hypothesized to involve the generation of suction within the lumen of Jacobson's organ and its duct. It is proposed that this suction is produced by pressure from the tongue and/or the anterior lingual processes.

Animals↗
PubMed1986

Isolation and physiological action of capillary permeability increasing-enzyme from the venom of Agkistrodon caliginosus.

A purified capillary permeability increasing-enzyme was obtained from Agkistrodon caliginosus venom by modification of our previous purification method. The purified enzyme, which had arginine esterase activity and strong capillary permeability increasing-activity, did not show caseinolytic, clotting or bradykinin-releasing activities. These properties of the enzyme were almost the same as those of the enzyme obtained by the previous purification method. When a mixture of the purified enzyme and bovine plasma or heated bovine plasma was injected into depilated skin on the back of a rabbit, the capillary permeability increasing-activity was much greater than that induced by injection of the enzyme alone. The substance which increases the capillary permeability was extracted from the incubated mixture of bovine plasma and the enzyme with 50-70% ethanol. Its activity was lost on treatment with carboxypeptidase A. From these results, it is supposed that the increase in capillary permeability induced by the enzyme is due to a low molecular weight peptide released from a protein in bovine plasma by the proteolytic action of the enzyme.

Animals↗
PubMed1997

[Using lyophilization to the preparation of drug paper disks for antimicrobial susceptibility test].

It was found that the paper disks used in the antimicrobial susceptibility test could be prepared by natural drying at 37 degrees C, but the drug distribution between these disks is not so enen as determined by antimicrobial inhibitory test, thus it was difficult to fit the needs of the national standards. Alternatively, we applied the lyophilization technique to the disks preparation and 12 batches, of different antibiotic disks were made out and found that the difference between disks is reduced, and all are meet to the national requirement. It is supposed that the capillary action may play a role in the variation of drug distribution in the natural drying process, and the lyophilization process avoided the capillary action, hence the more even distributed antibiotic disks are produced. The preparation of lyophilized disks is a simple and practical method that could be used in the antimicrobial susceptibility tests in hospital.

Freeze Drying↗
PubMedDate not supplied

Drawtex: a unique dressing that can be tailor-made to fit wounds.

Drawtex is a new and innovative dressing using dispersion technology which works on capillary action. This promotes moist wound healing and provides the optimum environment at the wound interface. This dressing has the ability to absorb exudate 30 times it own weight. The unique capillary action draws the exudate away from the wound bed and into the core of the dressing from where it disperses into a second layer of Drawtex. The practitioner tailors the Drawtex to conform to the wound bed. Drawtex's non-adherence reduces the frequency of dressing change after the first week. This is not the only benefit as it is also very cost-effective at half the price of other modern dressing products.

Absorption↗
PubMed2002

Nanochannels on a fused-silica microchip and liquid properties investigation by time-resolved fluorescence measurements.

We have fabricated nanometer-sized channels, demonstrated a technique for the introduction of liquid into the channels, and carried out time-resolved fluorescence measurements of aqueous solutions. In this study, 330-nm- and 850-nm-sized channels were fabricated on fused-silica substrates by fast atom beam etching and hydrofluoric acid bonding methods. A liquid introduction method utilizing capillary action was demonstrated. The liquid introduction was observed under an optical microscope, and the liquid velocity during the introduction was analyzed by surface energy and macroscale hydrodynamics. The liquid velocity due to capillary action in the nanometer-sized channel seemed more than four times slower than the estimation. Then, aqueous solutions of rhodamine 6G (R6G), sulforhodamine 101 (SR101), and rhodamine B (RB) in the channels were measured by time-resolved fluorescence spectroscopy; spectra of the same solution in a 250-microm-sized channel were also measured as a reference for the macrospace. Although the fluorescence spectra in the 330-nm-, 850-nm- and 250-microm-sized channels agreed with one another, the fluorescent decays in the nanometer-sized channels were faster for R6G and SR101 and slower for RB than the respective decays in the 250-microm-sized channels. The results suggested the solutions had lower dielectric constants and higher viscosities in the nanometer-sized channels.

Journal Article↗
PubMed2002

Review of an independent audit into the clinical efficacy of VACUTEX.

An independent report was completed and analysed by Pharmaceutical Research Associates International in August 2001 (Pro-Tex, 2001). This company provides a service to carry out independent project work and research studies within the healthcare sector. The project involved 73 tissue viability nurses and 93 patients, whereby the performance of VACUTEX capillary action wound dressing was assessed on both acute and chronic wounds. The audit takes into account the varying cultures across England and Wales and demonstrates this rapid method of comparing previous dressings used on a multitude of wound types, with analysis focusing on the versatility and efficacy of the VACUTEX capillary action wound dressing. This article reviews the findings of the audit.

Bandages↗
PubMed2005

Isolation of plasma from whole blood using planar microfilters for lab-on-a-chip applications.

Researchers are actively developing devices for the microanalysis of complex fluids, such as blood. These devices have the potential to revolutionize biological analysis in a manner parallel to the computer chip by providing very high throughput screening of complex samples and massively parallel bioanalytical capabilities. A necessary step performed in clinical chemistry is the isolation of plasma from whole blood, and effective sample preparation techniques are needed for the development of miniaturized clinical diagnostic devices. This study demonstrates the use of passive, operating entirely on capillary action, transverse-flow microfilter devices for the microfluidic isolation of plasma from whole blood. Using these planar microfilters, blood can be controllably fractionated with minimal cell lysis. A characterization of the device performance reveals that plasma filter flux is dependent upon the wall shear rate of blood in the filtration channel, and this result is consistent with macroscale blood filtration using microporous membranes. Also, an innovative microfluidic layout is demonstrated that extends device operation time via capillary action from seconds to minutes. Efficiency of these microfilters is approximately three times higher than the separation efficiencies predicted for microporous membranes under similar conditions. As such, the application of the microscale blood filtration designs used in this study may have broad implications in the design of lab-on-a-chip devices, as well as the field of separation science.

Cell Separation↗
PubMed2003

Tumor-inhibiting platinum(II) complexes with aminoalcohol ligands: comparison of the mode of action by capillary electrophoresis and electrospray ionization-mass spectrometry.

Capillary electrophoresis (CE) was used as an assay for studying the interaction of (SP-4-2)-bis[(R)-(-)-2-aminobutanol)dichloroplatinum(II) (1) and (SP-4-2)bis(4-aminobutanol)dichloroplatinum(II) (2) with guanosine 5'-monophosphate (GMP). CE kinetic measurements carried out at two physiological pH levels indicated that upon increasing the pH, 1 showed an appreciable change in binding behavior, with the rate of binding increased for more than 10 times as expressed by apparent half-life values of GMP (6.1 and 62.2 h at pH 6.0 and 7.4, respectively). The rate of GMP binding for 2 remained comparatively less affected by pH (half-lives of 8.5 and 10.6 h, respectively). Regardless of the nature of platinum complex and pH, the reaction with GMP tends to be decelerated at increased chloride concentrations in solution, this effect being particularly pronounced when changing from 4 mM (intracellular level) to 100 mM (extracellular level). The kinetic differences of platinum complexes were characterized in terms of the respective GMP-adducts structure, independently identified by means of off-line electrospray ionization-mass spectrometry. Also addressed was the interpretation of binding behavior as based on the structural features of the intact complexes, namely differing inclination to intramolecular chelation.

Antineoplastic Agents↗
PubMed2006

Segmentation of volumetric MRA images by using capillary active contour.

Precise segmentation of three-dimensional (3D) magnetic resonance angiography (MRA) images can be a very useful computer aided diagnosis (CAD) tool for clinical routines. Level sets based evolution schemes, which have been shown to be effective and easy to implement for many segmentation applications, are being applied to MRA data sets. In this paper, we present a segmentation scheme for accurately extracting vasculature from MRA images. Our proposed algorithm models capillary action and derives a capillary active contour for segmentation of thin vessels. The algorithm is implemented using the level set method and has been applied successfully on real 3D MRA images. Compared with other state-of-the-art MRA segmentation algorithms, experiments show that our method facilitates more accurate segmentation of thin blood vessels.

Algorithms↗
PubMed1986

Development of a simple device for processing whole-blood samples into measured aliquots of plasma.

A capillary processor and aliquoter has been designed and fabricated that is capable of accepting aliquots of whole blood and automatically processing them into discrete aliquots of plasma. The device consists of two disks, each of which contains 16 individual capillaries and a processing rotor. One disk accepts larger capillaries that hold approximately 100 microL of whole blood each. The second disk accepts 2.54-cm-long precision capillaries of various internal diameters, which provide exact sample volumes from 1 to 10 microL. The processing rotor contains 16 individual compartments and chambers to accept both disks. Applying centrifugal force transfers the aliquots of whole blood into their respective compartments, where they are separated into cellular and plasma fractions. As the rotor speed is slowly decreased, an aliquot of plasma is withdrawn by capillary action into each measuring capillary. The disk containing the 16 measured aliquots of plasma is then removed and placed into a modified rotor for conventional centrifugal analysis. This device can entrain and deliver microliter volumes of liquids with precision and accuracy (1-2%) near that of mechanical pipettes. Assays of the separated plasma aliquots also have acceptable precision (e.g., CVs approximately 3% for measurements of serum enzymes).

Blood Specimen Collection↗