(n.) A white crystalline semitransparent salt; potassium nitrate; saltpeter. See Saltpeter.
(n.) Native sodium carbonate; natron.
(n.) See Niter.
Example Sentences:
(1) The fast activation rates obtained by the photorelease of Ca2+ from nitr-5 are similar to those obtained with skinned skeletal fibres of actin-regulated muscle.
(2) The "caged" calcium chelator Nitr-5 was incorporated into isolated rat ventricular myocytes.
(3) First, nitr-5, a photolabile nitrobenzhydrol tetracarboxylate calcium chelator, which releases calcium in response to ultraviolet light, was used.
(4) This paper introduces nitr-2, a new Ca2+ chelator designed to release Ca2+ upon illumination with near UV (300-400 nm) light.
(5) Laser-induced photolysis of the caged calcium molecule, nitr-5, was used to generate a rapid jump in free Ca2+ (within 1 ms) at the site of the sarcoplasmic reticulum, thus overcoming delays due to Ca2+ diffusion from the bathing solution.
(6) Nitr-5 or the related compounds nitr-2 and nitr-7, complexed with Ca2+, were introduced into rat sympathetic ganglion cells by dialysis from a patch pipette electrode operating in the whole-cell, voltage-clamp mode.
(7) A quantitative estimate of the spatial distribution of intracellular [Ca2+] changes in large cells filled with a high concentration of nitr-2 and exposed to an intense UV flash is offered.
(8) The fluorescence properties of the calcium indicators Fura-2 and Fluo-3 have been investigated in the presence of the 'caged calcium' photolabile chelators Nitr-5 and DM-nitrophen.
(9) To overcome diffusion delays, rapid increases in the concentrations of Ca2+ and Ins(1,4,5)P3 were produced by laser photolysis of "caged Ca2+" (Nitr-5) and "caged Ins(1,4,5)P3".
(10) The method consisted of equilibrating a myofibrillar bundle (100 micrograms diameter) in a solution containing 0.1 mM-nitr-5 (initial pCa 6.8-6.6) and then exposing it to a UV laser pulse.
(11) By increasing the laser pulse energy or the initial Ca2+ loading of the nitr-5, the post-photolysis pCa was varied from 6.7 to 6.0; the CICR response increased in size over this pCa range.
(12) In intact muscles loaded with the photolabile Ca2+ chelator, nitr-5, photo-activated release of Ca2+ during the slow wave cycle produced changes consistent with activation of Ca2(+)-dependent outward currents.
(13) Nitr-5 was loaded into the hair cell by incubation with the membrane-permeable form of the compound (nitr-5 AM).
(14) Fluo-3 can also be microinjected into fibroblasts along with photolabile compounds such as nitr-5 and caged inositol trisphosphate for photorelease experiments.
(15) Although IM is not primarily Ca2+ dependent, small increases in [Ca2+]i by photolysis of the "caged" Ca2+ chelator nitr-5 or by evoking action potentials augmented, while larger increases inhibited, IM.
(16) Each flash-evoked current rose rapidly to a peak and decayed to half in 3-12 s. Our model mimicked this behavior when it included diffusion of calcium and nitr perpendicular to the surface of the neuron facing the flashlamp.
(17) To delineate the roles of presynaptic potential and calcium entry in transmitter release, we have used nitr-5, a photolabile calcium chelator, and a voltage-clamp technique to control intracellular calcium and membrane potential independently at a synapse formed between cell bodies of cultured neurons of the fresh water snail Helisoma trivolvis.
(18) In contrast, Ca2+ photorelease from nitr-5 had a biphasic effect: a small, rapid inactivation of the Ca2+ current was followed by a slow potentiation.
(19) We have studied calcium-activated potassium current, IK(Ca), and calcium-activated nonspecific cation current, INS(Ca), in Aplysia bursting pacemaker neurons, using photolysis of a calcium chelator (nitr-5 or nitr-7) to release "caged calcium" intracellularly.
(20) Light-induced Ca2+ release from the Ca2+ complex of Nitr-5 altered the FTIR spectra of sarcoplasmic reticulum vesicles and purified Ca(2+)-ATPase preparations.
Nitrogen
Definition:
(n.) A colorless nonmetallic element, tasteless and odorless, comprising four fifths of the atmosphere by volume. It is chemically very inert in the free state, and as such is incapable of supporting life (hence the name azote still used by French chemists); but it forms many important compounds, as ammonia, nitric acid, the cyanides, etc, and is a constituent of all organized living tissues, animal or vegetable. Symbol N. Atomic weight 14. It was formerly regarded as a permanent noncondensible gas, but was liquefied in 1877 by Cailletet of Paris, and Pictet of Geneva.
Example Sentences:
(1) These results are discussed in relation to the possible existence of enzyme-bound intermediates of nitrogen fixation.
(2) The measurement of the intestinal metabolism of the nitrogen moiety of glutamic acid has been investigated by oral ingestion of l-[15N]glutamic acid and sampling of arterialized blood.
(3) The induction of cells with two Y chromosomes by nitrogen mustard (NM) was examined.
(4) The disappearance of the herbicide, Avadex (40% diallate), from five agricultural soils (differing in either pH, carbon content, or nitrogen content), incubated under sterile and non-sterile conditions, was followed for a period of 20 weeks.
(5) Suspensions of isolated insect flight muscle thick filaments were embedded in layers of vitreous ice and visualized in the electron microscope under liquid nitrogen conditions.
(6) Airway closure (CV), functional residual capacity (FRC) and the distribution of inspired gas (nitrogen washout delay percentage, NWOD %) and arterial oxygen tension (PaO2) was measured by standard electrodes in eight extremely obese patients before and after weight loss (mean weights 142 and 94 kg, respectively) following intestinal shunt operation.
(7) Formula fed infants retained more nitrogen and gained weight faster.
(8) Triglyceride (Trigly) in female dogs, glutamic-pyruvic transaminase (GPT) and urea nitrogen (Urea-N) in male dogs tended to increase.
(9) Nitrogen retention was curvilinear in relation to metabolic live weight (kg0.75) in both series.
(10) Corynebacterium parvum-treated mice produce large amounts of circulating nitrogen oxides and develop a severe liver injury in response to lipopolysaccharide (LPS).
(11) Eight men and eight women each performed peak oxygen intake tests on a cycle ergometer breathing ambient air and a mixture of 12% oxygen in nitrogen (equivalent to an altitude of 4400 m) in the two experiments.
(12) From this, it was suggested that a negligible amount of oestradiol was released from these compounds and that the oestradiol moiety was useful as a carrier for the nitrogen mustard moiety.
(13) The intravenous administration of ovine placental lactogen to pregnant and non-pregnant sheep produced significant acute decreases in plasma free fatty acid, glucose and amino nitrogen concentrations.
(14) In contrast, nitrogen incubation did not alter the basal levels of TBA reactants except for a small rise associated with VE deficiency.
(15) MCT TPN was found to have some disadvantages, especially with regard to nitrogen balance and plasma albumin levels.
(16) Nitrogen mustard (N2M) treatment of rabbits induced neutropenia, and, in ligated ileal loops, it inhibited fluid secretion induced by salmonella or by cholera toxin (CT).
(17) For dipeptides containing the amino terminal residues glycine, alanine and phenylalanine, abstraction of the hydrogen from the carbon adjacent to the peptide nitrogen was the major process leading to the spin-adducts.
(18) The raw data are obtained by capillary gas chromatography using a nitrogen-phosphorus detector.
(19) Total protein, RNA, DNA, nitrogen, free amino acids and water content were determined in both lymphatic organs.
(20) This is the first evidence supporting carbon-nitrogen bond formation as the initial site of interaction between the two substrate molecules.