(n.) One of the very small invisible particles of which all matter is supposed to consist.
(n.) The smallest part of any substance which possesses the characteristic properties and qualities of that substance, and which can exist alone in a free state.
(n.) A group of atoms so united and combined by chemical affinity that they form a complete, integrated whole, being the smallest portion of any particular compound that can exist in a free state; as, a molecule of water consists of two atoms of hydrogen and one of oxygen. Cf. Atom.
Example Sentences:
(1) A series of human cDNA clones of various sizes and relative localizations to the mRNA molecule were isolated by using the human p53-H14 (2.35-kilobase) cDNA probe which we previously cloned.
(2) Glucocorticoids have numerous effects some of which are permissive; steroids are thus important not only for what they do, but also for what they permit or enable other hormones and signal molecules to do.
(3) The results demonstrated that K2PtCl4 was bound to a greater degree than CDDP in this system with 3-5 and 1-2 platinum atoms respectively, bound per transferrin molecule.
(4) Complementarity determining regions (CDR) are conserved to different extents, with the first CDR region in all family members being among the most conserved segments of the molecule.
(5) Even with hepatic lipase, phospholipid hydrolysis could not deplete VLDL and IDL of sufficient phospholipid molecules to account for the loss of surface phospholipid that accompanies triacylglycerol hydrolysis and decreasing core volume as LDL is formed (or for conversion of HDL2 to HDL3).
(6) However, the presence of these two molecules was restored if testosterone was supplemented immediately after orchiectomy.
(7) In the second approach, attachment sites of DTPA groups were directed away from the active region of the molecule by having fragment E1,2 bound in complex, with its active sites protected during the derivatization.
(8) PMNs could be primed for PMA-triggered oxidative burst by muramyl peptide molecules (MDP) and two of its adjuvant active nonpyrogenic derivatives.
(9) These same molecules may be equally responsible for the pathologic characteristics of the immune response seen, for example, in inflammatory bowel diseases.
(10) A cDNA library prepared from human placenta has been screened for sequences coding for factor XIIIa, the enzymatically active subunit of the factor XIII complex that stabilizes blood clots through crosslinking of fibrin molecules.
(11) T cell costimulation by molecules on the antigen presenting cell (APC) is required for optimal T cell proliferation.
(12) The lipid A moiety was shown to be responsible for this novel biological activity of the LPS molecule.
(13) Both systems indicated that the Kupffer cell modified endotoxin by enriching the lipid content of the molecule and shortening the length of the O-antigen.
(14) Photoreactions induced in that proper sensitizer molecules absorb UV-light or visible light.
(15) At 100 microM-ACh the apparent open time became shorter probably due to channel blockade by ACh molecules.
(16) Flow cytofluorometric analysis of the strain distribution of the molecules defined by the mAb revealed that two of the antibodies (I-22 and III-5) were directed against nonpolymorphic determinants of Thy-1, whereas V-8 mAb reacted only with Thy-1.2+ lymphocytes.
(17) At a fixed concentration of nucleotide the effectiveness of elution was proportional to the charge on the eluting molecule.
(18) The relative rates of reduction of several spin-labeled molecules that partition differently across the hy-drophobic-interface of inner membranes from rat liver mitochondria were investigated.
(19) The seve polypeptide chains investigated had generalyy similar properties; all contained two residues per molecule of tryptophan and N-acetylserine was the common N-terminal amino acid residue.
(20) Much information has accumulated on the isolation and characterization of a heterogeneous group of molecules that inhibit one or more of the bioactivities of interleukin 1.
Ozone
Definition:
(n.) A colorless gaseous substance (O/) obtained (as by the silent discharge of electricity in oxygen) as an allotropic form of oxygen, containing three atoms in the molecule. It is a streng oxidizer, and probably exists in the air, though by he ordinary tests it is liable to be confused with certain other substances, as hydrogen dioxide, or certain oxides of nitrogen. It derives its name from its peculiar odor, which resembles that of weak chlorine.
Example Sentences:
(1) We studied the effect of a 2-hour exposure to 0.6 ppm of ozone on bronchial reactivity in 8 healthy, nonsmoking subjects by measuring the increase in airway resistance (Raw) produced by inhalation of histamine diphosphate aerosol (1.6 per cent, 10 breaths).
(2) Carbon monoxide accelerates the reaction as measured by nitric oxide oxidation or ozone formation.
(3) It is suggested that the atmosphere of Athens favours the formation of secondary direct-acting mutagens due to the oxidation and nitration of PAH by ozone and nitrogen oxides, which are more abundant in the late spring months.
(4) Therefore, more research of the effects of ozone on birds seems to be necessary, both from a mechanistic and an ecological point of view.
(5) Using this assay, we studied the effects of exposure to ozone (O3), hexachlorobenzene (HCB), and bis(tri-n-butyltin)oxide (TBTO) on NK activity in rat lung.
(6) The campaign’s focus was the damage to the ozone layer caused by fluorinated gases, such as HFCs.
(7) Particular attention was given to both the qualitative and quantitative evaluation of ciliated cells in the nasal respiratory epithelium in response to ozone exposure.
(8) Results indicate also that ozone sensitivity, radiosensitivity, and mucoidy are pleiotropic properties of the lon gene.
(9) Endothelial prostacyclin synthesis returned to baseline levels by 12H after ozone exposure, a time point which was similar to the recovery time of unexposed endothelium treated with 0.5 uM acetylsalicylic acid.
(10) After ozone-exposed mice had been returned to ambient air for 10 days, ciliary regeneration occurred and, the major airways had a surface appearance approaching the normal state.
(11) Pulmonary fibrosis is a consequence of severe injury from some toxic agents including high doses of ozone.
(12) In the first experiment, rats were fed fat-free diets and exposed to ozone for 0, 1, 2, and 4 weeks.
(13) A mathematical model of ozone absorption, or for any soluble gas that has similar transport properties, is developed for a branching network of liquid-lined cylinders.
(14) Serial exposures to peak levels of ozone on several consecutive days are more characteristic of pollution episodes in the Northeast United States and may be associated with recurrent symptoms.
(15) The enhancement of metastasis due to ozone exposure varied with length of exposure and concentration of ozone.
(16) The present data indicate that the incidence of skin cancer would increase by approximately 2% for each percent ozone reduction.
(17) And yet, trusting the science, and with international leadership, an agreement – the Montreal Protocol – was signed within two years of the discovery of a hole in the ozone layer in the southern polar region.
(18) Ozonized water placed in an open dish kept up antimicrobial activity for the first 20 minutes, but after 30 minutes this activity decreased substantially.
(19) However, single, 40-min exposures of RTE cells to approximately 10 ppm ozone did result in approximately 40% decreases in colony-forming efficiency.
(20) The present studies were undertaken to examine the effects of exposing asthmatics to ozone concentrations that occur in the environment.