(n.) A nonmetallic element occurring abundantly in borax. It is reduced with difficulty to the free state, when it can be obtained in several different forms; viz., as a substance of a deep olive color, in a semimetallic form, and in colorless quadratic crystals similar to the diamond in hardness and other properties. It occurs in nature also in boracite, datolite, tourmaline, and some other minerals. Atomic weight 10.9. Symbol B.
Example Sentences:
(1) The compound caused extensive clumping, of cells, which appeared not to be related to the ability of boronates to esterify to diols.
(2) Examples are p-boronophenylalanine or boronated porphyrius.
(3) Fractions from the boronate gel column or aliquots of NaIO4-treated cell extract are quantitated directly by the RIA.
(4) The second part of the paper describes a case where neodynium-iron-boron magnets were used to assist eruption of an unerupted, vertically impacted upper right canine.
(5) A neodymium iron boron magnet is attached to the unerupted tooth, and a second, larger magnet is incorporated in a removable appliance.
(6) The various boron compounds being investigated for NCT are evaluated on the basis of necessary minimum boron content in tumor.
(7) N-Allylation of a trimethoxybenzazepine followed by cleavage of the methyl ethers with boron tribromide was the preferred method.
(8) Because boronated phenylalanine has been demonstrated to be preferentially taken up by melanoma cells through the biosynthetic pathway for melanin, there is special interest in a trial of boron neutron capture therapy for metastatic melanoma in brain.
(9) After separation by thin-layer chromatography, the bands of the lipid classes studied were scraped off, transmethylated according to the boron trifluoride-methanol procedure, and the fatty acid methyl esters were extracted and analysed.
(10) However, at 1000 and 2000 ppm boron, male fertility was significantly reduced.
(11) A parameter of major importance is the minimum concentration of boron needed in tumor in order to produce improved results in cancer therapy.
(12) Boron-11 spectral intensities decreased in the living rat over a 25-h period.
(13) In some areas, wastewater is used for irrigation and crops grown under these conditions are generally confined to those relatively insensitive to boron toxicity.
(14) These data indicate that broilers grown on boric acid-treated litter do not consume enough boric acid to cause elevated boron levels in tissues.
(15) In the course of re-assessment of boron-neutron capture therapy (BNCT) for malignant brain tumors, fractionation of neutron irradiation has been proposed.
(16) Six-day exposures of the differentiated cells to a 1-mM dose of aluminum or boron yielded increases in tau protein immunoreactivity to the monoclonal antibodies Tau-1 and Alz-50.
(17) Recovery of the serine and threonine derivatives was improved by substituting boron trifluoride-diethyl etherate for trifluoroacetic acid in the thiazolinone cleavage reactions.
(18) Boron levels in the brain dropped about 6%-8% and were more diffusely distributed on the images obtained 30 minutes after BSH infusion.
(19) The boron derivatives also caused L-1210 DNA strand scission.
(20) Glycosylation was estimated using boronate affinity chromatography with the myosin dissolved in a pyrophosphate buffer, the glycosylated myosin being displaced with sorbitol.
Chemical
Definition:
(a.) Pertaining to chemistry; characterized or produced by the forces and operations of chemistry; employed in the processes of chemistry; as, chemical changes; chemical combinations.
(n.) A substance used for producing a chemical effect; a reagent.
Example Sentences:
(1) Brain and ganglia of embryonic Periplaneta americana were grown for 2 to 3 weeks in a chemically defined medium.
(2) Stimulation of human leukocytes with various chemical mediators such as TPA, f-Met-Leu-Phe, LTB4, etc.
(3) This suggested that the chemical effects produced by shock waves were either absent or attenuated in the cells, or were inherently less toxic than those of ionizing irradiation.
(4) At 36 h postsurgery, RBCs were examined by 23Na-NMR by using dysprosium tripolyphosphate as a chemical shift reagent.
(5) The absorption of ingested Pb is modified by its chemical and physical form, by interaction with dietary minerals and lipids and by the nutritional status of the individual.
(6) Changes in cardiac adenosine triphosphate (ATP), phosphocreatine (PCr) and inorganic phosphate (Pi) were followed and intracellular pH (pHi) was estimated from the chemical shift of Pi.
(7) Maximal aberration yields were observed for 2,4-diaminotoluene, 2,6-diaminotoluene and cytosine beta-D-arabinofuranoside from 17 to 21 h, eugenol from 15 to 21 h, cadmium sulfate from 15 to 24 h and 2-aminobiphenyl, from 17 to 24 h. For adriamycin at 1 microM, the % aberrant cells remained elevated throughout the period from 9 to 29 h, while small increases at 0.1 microM ADR were found only at 13 and at 25 h. For most chemicals the maximal aberration yield occurred at a different time for each concentration tested.
(8) 2.39pm BST The European Union called for a "thorough and immediate" investigation of the alleged chemical attack.
(9) "With hyperspectral imaging, you can tell the chemical content of a cake just by taking a photo of it.
(10) The deactivated columns had the residual silanols on the silica gel chemically inactivated to reduce the interaction with basic groups or analytes.
(11) A sperm whale myoglobin gene containing multiple unique restriction sites has been constructed in pUC 18 by sequential assembly of chemically synthesized oligonucleotide fragments.
(12) On the basis of obtained data on the uniformity of chemical compounds of the secretion of glands belonging to different groups their common origin has been suggested.
(13) In spite of important differences in size, chemical composition, polymer density, and configuration, biological macromolecules indeed manifest some of the essential physical-chemical properties of gels.
(14) In contrast sham-hemodialysis in group CA and group PS, respectively, did not result in significant increases in amino acid efflux from the leg implying that the protein catabolic effect of blood membrane contact depends on the chemical properties of dialysis membranes.
(15) We investigated this suppression quantitatively, using a chemical assay for cell-bound and dissolved capsular polysaccharide.
(16) We previously established that the binding constant (Ka) of this receptor site for the chemically synthesized model AGE, 2-(2-furoyl)-4(5)-(2-furanyl)-1H- imidazole-butyric acid (FFI-BA), on cells of the mouse macrophagelike cell line RAW 264.7 is identical to that for AGE proteins.
(17) They included lectins such as wheat germ agglutinin (WGA), concanavalin A and phytohemagglutinin, and a chemical cross-linker, glutaraldehyde, in addition to anti-IL-2R monoclonal antibodies, HIEI and H-47.
(18) The reduction of such potentials can be explained in terms of collision between the antidromic volleys and those elicited orthodromically by chemical and thermic stimulation.
(19) In certain cases, the effects of these substances are enhanced, in others, they are inhibited by compounds that were isolated from natural sources or prepared by chemical synthesis.
(20) The use of gaseous insecticides in the chemical control of T. infestans is discussed.