(n.) A thin layer or fold of tissue, usually supported by a fibrous network, serving to cover or line some part or organ, and often secreting or absorbing certain fluids.
Example Sentences:
(1) Tryptic digestion of the membranes caused complete disappearance of the binding activity, but heat-treatment for 5 min at 70 degrees C caused only 40% loss of activity.
(2) The extents of phospholipid hydrolysis were relatively low in brain homogenates, synaptic plasma membranes and heart ventricular muscle.
(3) The patterns observed were: clusters of granules related to the cell membrane; positive staining localized to portions of the cell membrane, and, less commonly, the whole cell circumference.
(4) Activity of Na,K-ATPase activity was measured as a functional marker for synaptosomal membranes.
(5) The influence of the various concepts for the induction of lateral structure formation in lipid membranes on integral functional units like ionophores is demonstrated by analysing the single channel current fluctuations of gramicidin in bimolecular lipid membranes.
(6) Phospholipid methylation in human EGMs is distinctly different from that in rat EGMs (Hirata and Axelrod 1980) in that the human activity is not Mg++-dependent, and apparent methyltransferase I activity is located in the external membrane surface.
(7) The predicted non-Lorentzian line shapes and widths were found to be in good agreement with experimental results, indicating that the local orientational order (called "packing" by many workers) in the bilayers of small vesicles and in multilamellar membranes is substantially the same.
(8) Apparently, the irradiation with visible light of a low intensity creates an additional proton gradient and thus stimulates a new replication and division cycle in the population of cells whose membranes do not have delta pH necessary for the initiation of these processes.
(9) Using monoclonal antibodies directed against the plasma membrane of Madin-Darby canine kidney (MDCK) cells, we demonstrated previously that a glycoprotein with an Mr = 23,000 (gp23) had a non-polarized cell surface distribution and was observed on both the apical and basolateral membranes (Ojakian, G. K., Romain, R. E., and Herz, R. E. (1987) Am.
(10) The fraction of the viral dose which became cell associated was independent of the incubation temperature and increased with increasing target membrane concentration.
(11) Together these results suggest that IVC may operate as a selective activator of calpain both in the cytosol and at the membrane level; in the latter case in synergism with the activation induced by association of the proteinase to the cell membrane.
(12) The Cole-Moore effect, which was found here only under a specific set of conditions, thus may be a special case rather than the general property of the membrane.
(13) We have examined the insertion of bovine 17 alpha-hydroxylase (P45017 alpha) into the endoplasmic reticulum of COS 1 cells to evaluate the functional role of its hydrophobic amino-terminal sequence and membrane insertion.
(14) The transport of potassium ions through membranes of red blood cells was examined in in bitro experiments using a CMF of 4500 oersted.
(15) These membrane perturbation effects not observed with bleomycin-iron in the presence of a hydroxyl radical scavenger, dimethyl thiourea, or a chelating agent, desferrioxamine, were correlated with the ability of the complex to generate highly reactive oxygen species.
(16) Extensive studies during recent years have shown that the interaction between hormone and membrane-bound receptor can affect the receptor characteristics in at least two ways.
(17) Membranes of this material were filled with islets of Langerhans and implanted in the peritoneal cavity of rats.
(18) The penicillin-resistant Enterococcus hirae R40 has a typical profile of membrane-bound penicillin-binding proteins (PBPs) except that the 71 kDa PBP5 of low penicillin affinity represents about 50% of all the PBPs present.
(19) To investigate the mechanism of enhanced responsiveness of cholesterol-enriched human platelets, we compared stimulation by surface-membrane-receptor (thrombin) and post-receptor (AlF4-) G-protein-directed pathways.
(20) Moreover, in DCVC-treated cells the mitochondria could not be stained with rhodamine-123, indicating severe mitochondrial damage and loss of membrane potential.
Tonicity
Definition:
(n.) The state of healthy tension or partial contraction of muscle fibers while at rest; tone; tonus.
Example Sentences:
(1) It is suggested that diabetes causes selective changes in the functioning of Gi in adipocyte membranes which removes the tonic GTP-dependent inhibitory function of this G-protein.
(2) Other Christmas favourites, including stollen, organic mince pies and Schweppes tonic will also be included among 100 seasonal products on the list of 1,000 items which shoppers can choose from over the next few months.
(3) In intact cell preparations, diamide produced a slow tonic contraction, consistent with myofibril activation.
(4) However, tetanic stimulation gave the same results as in untreated preparations when the tonicity was increased.
(5) Stimulus-response characteristics suggested that this system was well suited for a role in tonic inhibition of sympathetic activity.
(6) The amplitude was 15-70% as large as the tonic component of the K-contracture induced by 40 mM K. Theophylline (10 mM), 0.1 mM papaverine and 1 microM isoprenaline nearly abolished, and 1 mM cAMP partly depressed the tonic contraction of K-contracture, whereas the tonic contraction induced by the test solution was unaffected.
(7) While tonic pupil and reduced sweating can be attributed to the affection of postganglionic cholinergic parasympathetic and sympathetic fibres projecting to the iris and sweat glands, respectively, the pathogenesis of diminished or lost tendon jerks remains obscure.
(8) Some organization schemes concerning locomotor and scratching rhythmicity generators are considered, such as: two half-centres with reciprocal inhibitory connections and tonic excitatory influences on these half-centres: two half-centres with inhibitory-excitatory connections and tonic excitatory influences on one half-centre; ring structures consisting of more than two functional groups of neurons with excitatory and inhibitory connections between them.
(9) Overall, carbamazepine and phenytoin are recommended drugs of first choice for single-drug therapy of adults with partial or generalized tonic-clonic seizures or with both.
(10) It was previously believed that the period of the circadian clock was primarily responsive to externally imposed tonic or phasic events.
(11) For now, he leans on the bar – a big man, XL T-shirt – and, in a soft Irish accent, orders himself a small gin and tonic and a bottle of mineral water.
(12) Relying on traditional medicine, all 20 women reported eating brown seaweed soup for 20 days after childbirth, and 5 said that they took tonic herbs during the puerperium.
(13) Amplitudes of the tonic response evoked by 39 mM-K+ in intact muscle tissues and the contraction induced by 0.3 microM-Ca2+ in skinned muscle were much the same.
(14) Tonic sympathetic neural control of heart rate was inferred from bradycardia after treatment with the adrenergic neuron-blocking agent, bretylium tosylate.
(15) These results clearly indicate that in both intact and OVX does, endogenous NPY is in part responsible for maintaining basal, tonic LH secretion.
(16) All motoneuron firing during fictive swimming is associated with a tonic depolarization that falls away slowly once firing stops, is increased by hyperpolarizing current, and is reduced by depolarizing current.
(17) The tonic influences were expressed in an increase in the amplitude parameters of the responses of the visual cortex in conditions of the formation in the posterolateral nucleus of the thalamus of a focus of heightened excitability (anode polarization), and their perceptible diminution with potassium depression in this nucleus.
(18) Lateralization may be an expression of reflex constraints bound initially to the infant's tonic-neck posture, with later development less reflex-patterned during the acquisition of more sophisticated information-processing strategies.
(19) During each session, measurements were made of either tonic accommodation or tonic vergence 30 s before stimulus onset and at 0.5, 2, 4, 6, 8, 10, 12, and 14 min after stimulus offset.
(20) The findings can be summarized as follows: (1) The effective concentration of SDS for termination of shark tonic immobility (an immediate and fast response) was close to its critical micellar concentration in sea water (70 microM).