(1) Models able to describe the events of cellular growth and division and the dynamics of cell populations are useful for the understanding of functional control mechanisms and for the theoretical support for automated analysis of flow cytometric data and of cell volume distributions.
(2) Local embolism, vertebral distal-stump embolism, the dynamics of hemorrhagic infarction and embolus-in-transit are briefly described.
(3) Therefore, we have developed a powerful new microcomputer-based system which permits detailed investigations and evaluation of 3-D and 4-D (dynamic 3-D) biomedical images.
(4) Brain damage may be followed by a number of dynamic events including reactive synaptogenesis, rerouting of axons to unusual locations and altered axon retraction processes.
(5) Thus, mechanical restitution of the ventricle is a dynamic process that can be assessed using an elastance-based approach in the in situ heart.
(6) Time-series analysis and multiple-regression modeling procedures were used to characterize changes in the overall incidence rate over the study period and to describe the contribution of additional measures to the dynamics of the incidence rates.
(7) These results provide evidence that trait selection can change gonadotrophin receptor concentration and the dynamics of hormone secretion during the oestrous cycle of the mouse.
(8) Full consideration should be given to the dynamics of motion when assessing risk factors in working tasks.
(9) We describe both the three supportive psychotherapeutic steps, which may last months to years including subsequent dynamically psychotherapeutic strategies as well as the reactions of the auxiliary therapist function on the students.
(10) The dynamics has a hierarchical structure which has at least two levels.
(11) It may, however, be useful to compare local wall dynamics in the more isometrically-contracting basal segment with those in the middle portion which brings about most of the emptying of the ventricle.
(12) Echocardiography makes possible the analysis of cardiac structures and their dynamics.
(13) The design of a simple dynamic knee simulator is described.
(14) The most important causal factor, well illustrated by pressure studies, was the presence of a dynamic or static deformity leading to local areas of peak pressure on insensitive skin.
(15) The dynamic influence of continuously administered fentanyl (0.040 mg.kg-1.h-1 i.v.
(16) Dynamics in the changes was established among the workers from the production of "Synthetic rubber and latex", associated with the duration of occupational exposure to styrene and divinyl.
(17) Our dynamic study indicated that: 1) a bolus injection of contrast medium with our method of CTA (CTA-B) produced an attenuation difference between liver and tumor which was about double that obtained with standard methods for CTA, and 2) marked tumor-liver attenuation differences (above 20 HU) persisted for more than 60 s in CTA-B and for not more than 20 s with conventional methods for CTA.
(18) The paper develops a model as a framework for monitoring the course of the program through the policy cycle and recommends that the policy process be considered as dynamic, interactive, and evolutionary.
(19) These results suggest that the central shift in blood volume with WI reduces the sympathoadrenal response to high-intensity dynamic exercise.
(20) A variant of the FitzHugh-Nagumo model is proposed in order to fully make use of the computational properties of intraneuronal dynamics.
Tautomerism
Definition:
(n.) The condition, quality, or relation of metameric substances, or their respective derivatives, which are more or less interchangeable, according as one form or the other is the more stable. It is a special case of metamerism; thus, the lactam and the lactim compounds exhibit tautomerism.
Example Sentences:
(1) The coupled dienone-phenol re-arrangement and keto-enol tautomerism of this quinone methide produce the observed 3,4-dihydroxybenzaldehyde.
(2) On the other hand, results indicate that the protonation of formycin and its derivatives at the N1 atom leads to a change in their tautomeric preference from N7-H to N8-H.
(3) The inhibitor trapping system, however, prevents the inactivation of succinate dehydrogenase under the conditions when the rate of tautomeric oxaloacetate enol in equilibrium oxaloacetate ketone interconversion is high.
(4) In contrast, equilibria of ring chain tautomerism and covalent hydration of aldoses are almost completely insensitive to the polarity of their surroundings.
(5) The importance of both tautomerism and protonation reactions in the mechanism of action of adenosine deaminase is studied by means of a quantitative structure activity relationships strategy.
(6) The possibility that this product is an equilibrium mixture with the tautomeric 4-hydroxycyclophosphamide has not been as yet defintely ruled out.
(7) In addition to being a possible mechanism for alteration of hydrogen bonding in oxidized DNA, this type of interaction gives a better understanding into N7-N9 tautomerism of adenine.
(8) The product 3-fluorooxalacetate is thus released from phosphoenolpyruvate carboxykinase as the keto form and is reduced more rapidly by reduced nicotinamide adenine dinucleotide with malate dehydrogenase than by the occurrence of tautomerization.
(9) These results strongly suggest that the anomeric, epimeric, and tautomeric form of the sugar phosphate substrates favored by both enzymes is the beta-D-fructofuranose form.
(10) Tautomerization of DOPA quinone to dehydroDOPA may thus be a factor in the sclerotization of natural structures incorporating DOPA containing proteins.
(11) For the complex formed between [5,5-2H,5-13C]ALA and methyl methanethiosulfonate (MMTS) modified PBG synthase, which does not catalyze PBG formation but can form a Schiff base adduct, the chemical shift of 44.2 ppm (line width 92 Hz) identifies an imine structure as the predominant tautomeric form of the Schiff base.
(12) delta 5-3-Ketosteroid isomerase (EC 5.3.3.1) catalyzes the isomerization of delta 5-3-ketosteroids to delta 4-3-ketosteroids by a conservative tautomeric transfer of the 4 beta-proton to the 6 beta-position with Tyr-14 as a general acid and Asp-38 as a general base [Kuliopulos, A., Mildvan, A. S., Shortle, D., & Talalay, P. (1989) Biochemistry 28, 149-159].
(13) The results are consistent with evidence for the formation of the first tetrahydropterin intermediate by a tautomerization without any requirement for NADPH.
(14) Its function is probably to maintain the orientation and tautomeric state of the imidazole ring of histidine-159.
(15) This suggests that a stable AP:C base mispair via two hydrogen bonds can be formed with the imino tautomer of C. These results stress the importance of the imino form of C in AP-induced mutagenesis and support the 'trigger mechanism', in which formation of one hydrogen bond between AP and C is considered to stimulate the tautomeric shift of AP or C. The calculated relative stabilities of various base pairs and mispairs were in good agreement with experimental findings.
(16) Whereas O6-MeGua did not form hydrogen bonds with cytosine (via usual, wobble, or unusual tautomeric structures), it did form a 1:1 hydrogen-bonded complex with protonated cytosine.
(17) Amide-imide tautomerism enables a cleanup of the extract.
(18) Ultraviolet and infrared spectrophotometric techniques have been utilized to demonstrate that the monoanionic form of 2-thiouracil in aqueous medium consists of an equilibrium mixture of two tautomeric monoanions, one due to dissociation of the N1 proton, the other to dissociation of the N3 proton, in the approximate ratio 1:1.
(19) Combined use of mass spectroscopy and 1H- and 13C-NMR spectroscopy established that it is the 4,8-anhydro derivative of N-acetylneuraminic acid and that in solutions it exists in two tautomeric forms.
(20) As a result of a concerted proton (tautomeric) shift in the linked residues of the hydrogen-bond chain, which includes the bound molecule, a charge separation occurs.