What's the difference between dissociation and mechanism?

Dissociation


Definition:

  • (n.) The act of dissociating or disuniting; a state of separation; disunion.
  • (n.) The process by which a compound body breaks up into simpler constituents; -- said particularly of the action of heat on gaseous or volatile substances; as, the dissociation of the sulphur molecules; the dissociation of ammonium chloride into hydrochloric acid and ammonia.

Example Sentences:

  • (1) These results show that the pathogenic phenotypes of MCF viruses are dissociable from the thymotropic phenotype and depend, at least in part, upon the enhancer sequences.
  • (2) Structure assignment of the isomeric immonium ions 5 and 6, generated via FAB from N-isobutyl glycine and N-methyl valine, can be achieved by their collision induced dissociation characteristics.
  • (3) It has recently been suggested that procaine penicillin existed in solution in vitro and in vivo as a "procaine - penicillin" complex rather than as dissociated ions.
  • (4) Elongation of existing RNA primers by the human polymerase-primase was semi-processive; following primer binding the DNA polymerase continuously incorporated 20 to 50 nucleotides, then it dissociated from the template DNA.
  • (5) Blood gas variables produced from a computed in vivo oxygen dissociation curve, PaeO2, P95 and C(a-x)O2, were introduced in the University Hospital of Wales in 1986.
  • (6) The data shows a dissociation between ferritin synthesis, cellular accumulation and secretion for which the mechanisms have still to be elucidated.
  • (7) Electromechanic dissociation, sinus bradycardia, nodal rhythm followed by idioventricular rhythm and asystole, were observed following myocardial rupture.
  • (8) Transcription studies in vitro on repression of the tryptophan operon of Escherichia coli show that partially purified trp repressor binds specifically to DNA containing the trp operator with a repressor-operator dissociation constant of about 0.2 nM in 0.12 M salt at 37 degrees , a value consistent with the extent of trp operon regulation in vivo.
  • (9) These differences in central connectivity mirror the reports on behavioral dissociation of the facial and vagal gustatory systems.
  • (10) In contrast, the enzymic domain of the colicin (T2) remained in the aqueous phase and was recovered in a highly active form as a consequence of its dissociation from the immunity protein.
  • (11) Predominantly observed defects included neural crest cells in ectopic locations, both within and external to the neural tube, and mildly deformed neural tubes containing some dissociating cells.
  • (12) Inhibition assays indicate an apparent dissociation constant (Kd) corresponding to 4 x 10(-9) M and an affinity constant (Ka) to 2.5 x 10(8)M-1 to K562 erythroleukemia cells.
  • (13) When CO was photolytically dissociated from the reduced protein two recombination processes were observed with rates almost identical with those observed in the stopped-flow experiments (k+1 = 3.3 X 10(3)M-1-S-1 and k+2 = 6.0 X 10(2)M-1-S-1).
  • (14) On the other hand, ultraviolet (320-nm) light, absorbed by 3-hydroxy-pyridinium cross-links which were rapidly photolyzed, partially dissociated polymeric collagen aggregates from bovine Achilles tendon after subsequent heating.
  • (15) The corresponding dissociation constants range from 2.8 nM for the native enzyme and 8.5 nM for the 96K fragment to approximately 15 nM for the 68K and 90K fragments [0.20 N KCl, 50 mM 3-(N-morpholino)propanesulfonic acid, and 1 mM CaCl2, pH 7.3, 25 degrees C].
  • (16) Addition of pyridoxal 5'-phosphate to slow dissociating, high affinity 5S R[3H]E2 dimers free in cytosol induced rapid [3H]E2 dissociation, although the receptor remained unaltered in the transformed dimerized state.
  • (17) If VF persisted or if countershock resulted in asystole or a nonperfusing rhythm (electrical-mechanical dissociation [EMD]), the alternate drug (naloxone or epinephrine) was then given.
  • (18) Addition of albumin or GTP to the incubation medium enhanced the specific binding of PGE2 by decreasing the dissociation constant of the low affinity-high capacity binding sites.
  • (19) Dissociated cerebral hemisphere cells from 4- to 7-day-old chick embryos were cultured either on a collagen or a polylysine substrate in a serum-containing medium.
  • (20) Incubation of the enzyme-inhibitor complex with the sulfhydryl reagent caused dissociation into active ribonuclease and inactive inhibitor.

Mechanism


Definition:

  • (n.) The arrangement or relation of the parts of a machine; the parts of a machine, taken collectively; the arrangement or relation of the parts of anything as adapted to produce an effect; as, the mechanism of a watch; the mechanism of a sewing machine; the mechanism of a seed pod.
  • (n.) Mechanical operation or action.
  • (n.) An ideal machine; a combination of movable bodies constituting a machine, but considered only with regard to relative movements.

Example Sentences:

  • (1) Such a signal must be due to a small ferromagnetic crystal formed when the nerve is subjected to pressure, such as that due to mechanical injury.
  • (2) These data suggest that the hybrid is formed by the same mechanism in the absence and presence of the urea step.
  • (3) Some common eye movement deficits, and concepts such as 'the neural integrator' and the 'velocity storage mechanism', for which anatomical substrates are still sought, are introduced.
  • (4) We have investigated the effect of methimazole (MMI) on cell-mediated immunity and ascertained the mechanisms of immunosuppression produced by the drug.
  • (5) One hour after direct mechanical cardiomassage (DMCM) a moderately pronounced edema of the intercellular spaces in the basal compartment of the seminiferous epithelium, normal content of lactate and succinate dehydrogenases, and a certain decrease in the activity of glucose-6-phosphate dehydrogenases and NAD- and NADP-diaphorases were noted.
  • (6) It is concluded that amlodipine reduces myocardial ischemic injury by mechanism(s) that may involve a reduction in myocardial oxygen demand as well as by positively influencing transmembrane Ca2+ fluxes during ischemia and reperfusion.
  • (7) 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.
  • (8) The following is a brief review of the history, mechanism of action, and potential adverse effects of neuromuscular blockers.
  • (9) However, the mechanism of the inhibitory action is still somewhat uncertain.
  • (10) It also provides mechanical support for the collateral ligaments during valgus or varus stress of the knee.
  • (11) We studied the hemodynamic changes caused by bronchoscopy under LA in mechanically ventilated patients and the effect of LA on the endoscopic decline in arterial pO2.
  • (12) Together these observations suggest that cytotactin is an endogenous cell surface modulatory protein and provide a possible mechanism whereby cytotactin may contribute to pattern formation during development, regeneration, tumorigenesis, and wound healing.
  • (13) Dilutional studies comparing the mechanism of inhibition of monoamine oxidase produced by Gerovital H3 and by ipronizid demonstrated that Gerovital H3 was a reversible inhibitor of monoamine oxidase.
  • (14) 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.
  • (15) Based on our results, we propose the following hypotheses for the neurochemical mechanisms of motion sickness: (1) the histaminergic neuron system is involved in the signs and symptoms of motion sickness, including vomiting; (2) the acetylcholinergic neuron system is involved in the processes of habituation to motion sickness, including neural store mechanisms; and (3) the catecholaminergic neuron system in the brain stem is not related to the development of motion sickness.
  • (16) Thus, mechanical restitution of the ventricle is a dynamic process that can be assessed using an elastance-based approach in the in situ heart.
  • (17) The mechanism by which pertussis toxin (PT) breaks the unresponsiveness of delayed-type hypersensitivity (DTH) to sheep red blood cells (SRBC) was examined in B10 mice.
  • (18) This suggests that a physiological mechanism exists which can increase the barrier pressure to gastrooesophageal reflux during periods of active secretion of the stomach, as occurs in digestion.
  • (19) The macrophage-derived product, interleukin 1 (IL 1) is thought to play an important regulatory role in the proliferation of T lymphocytes; however, its mechanism of action is unknown.
  • (20) Adding a layer of private pensions, it was thought, does not involve Government mechanisms and keeps the money in the private sector.