(n.) A substance, in the form of reddish brown, microscopic, prismatic crystals, formed from dried blood by the action of strong acetic acid and common salt; -- called also Teichmann's crystals. Chemically, it is a hydrochloride of hematin.
Example Sentences:
(1) The appearance of an abundant class of polyribosomes was correlated with globin synthesis by demonstrating that a discrete class of polyribosomes arises in cells treated with the inducers hexamethylene bisacetamide and hemin.
(2) Finding (d) indicates that steps involved in the restorative effect of these compounds may not contribute to the stimulation of the globin synthesis in hemin-deficient lysates.
(3) The destabilization of the red cell membrane skeleton in the presence of crude iHCR is caused by release of hemin, which lowers the stability of membrane skeleton by weakening the spectrin-protein 4.1-actin interaction.
(4) Hemin failed to increase P450 levels previously depressed by TPA indicating that TPA acts by lowering apocytochrome levels.
(5) Prior exposure of the adherent cell layer to high concentrations of hemin (10 microM) was found to have a beneficial effect on the support of newly seeded cultures; however, the effect of lower hemin concentrations (0.1-1 microM) on stromal cell layer formation was not significant.
(6) Hemin increased satellite cell fusion by 27%, but decreased cell proliferative rate by 30%.
(7) Inhibition of hemin-mediated O2 activation by bovine superoxide dismutase and the copper tetrammine complex has been examined.
(8) Upon incubation of the HCI preparation with hemin (5-10 microM), the eIF-2 alpha kinase is converted into an inactive form and appears to become associated with related peptides forming high molecular weight complexes which can be reversibly activated by 2-mercaptoethanol.
(9) When the prorepressor is converted to the hemin-controlled translational repressor, either by prolonged warming in the absence of hemin or by incubation with N-ethylmaleimide for 5 min, and then incubated briefly with [gamma-32P]-ATP and Mg2+, a protein that migrates as a 100 000 molecular weight component on sodium dodecyl sulfate-polyacrylamide gels becomes phosphorylated.
(10) Its activity is independent of cyclic AMP as well as of the calcium-dependent regulator protein and is inhibited by hemin.
(11) The spin-labeled hemins were recombined with apoproteins of hemoglobin (Hb), myoglobin (Mb), cytochrome c peroxidase (EC 1.11.1.5) and horseradish peroxidase (EC 1.11.1.7).
(12) A model compound with similar optical properties to the CO-ligated protein can be prepared in dimethyl sulfoxide from hemin chloride, imidazole, and CO using chromous acetate as the heme reductant.
(13) Porphyromonas gingivalis is capable of in vitro growth when iron sources are either complexed to hemin or host iron transport proteins, or exist in an inorganic form.
(14) An assumption is advanced that the P. vitale catalase contains two hemin groups located in two protein subunits.
(15) The effect of hemin administration on the level of hepatic delta-amino-levulinate synthase mRNA was also examined.
(16) We were not able to detect any reaction between the radical (see article) and the hemin group (which would result in a complex such as heme O-2).
(17) The N-acetylimidazole-reacted apoprotein supplemented with hemin and reacted with hydroperoxides, neither showed electronic absorption spectra of higher oxidation states nor an EPR doublet signal due to a tyrosyl radical.
(18) With iron porphyrins (hemin, heme and their complexes) the charge of the iron and the nature of axial ligands determine the position and intensity of the O-bands in the MOR spectrum.
(19) Since S. typhimurium LT2 is not able to incorporate hemin, the identification of the mutants not stimulated by Delta-ALA was made on the basis of the simultaneous loss of catalase activity and cytochromes.
(20) Hemin, known to inactivate IRF in vivo, showed a similar, reversible effect in vitro, presumably by oxidizing IRF.
Laboratory
Definition:
(n.) The workroom of a chemist; also, a place devoted to experiments in any branch of natural science; as, a chemical, physical, or biological laboratory. Hence, by extension, a place where something is prepared, or some operation is performed; as, the liver is the laboratory of the bile.
Example Sentences:
(1) These data indicate a steady improvement in laboratory performance over the last 10 years.
(2) Clinical surveillance, repeated laboratory tests, conventional radiology, and especially ultrasonography and CT scan all contributed to the preoperative diagnosis.
(3) If the method was taken into routine use in a diagnostic laboratory, the persistence of reverse passive haemagglutination reactions would enable grouping results to be checked for quality control purposes.
(4) A disease in an IgD (lambda) plasmocytoma is described, where after therapy with Alkeran and prednisone a disappearance of all clinical and laboratory findings indicating an activity could be observed.
(5) The procedure used in our laboratory was not able to provide accurate determination of the concentrations of these binding forms.
(6) Well tolerated from the clinical and laboratory points of view, it proved remarkably effective.
(7) Since 1979, patients started on long-term lithium treatment at the Psychiatric Hospital in Risskov have been followed systematically with recording of clinical and laboratory variables before the start of treatment, after 6 and 12 months of treatment, and thereafter at yearly intervals.
(8) It was established that nonsurgical methods of transplantation with laboratory animals were less time-consuming and were more readily applicable.
(9) Chromatography and immunoassays are the two principal techniques used in research and clinical laboratories for the measurement of drug concentrations in biological fluids.
(10) The detection of these antibodies is difficult owing to the lack of standardization and of specificity of the laboratory tests.
(11) The results confirm studies performed in our laboratory on cytotoxicity and on functional membrane proteins of fungal and mammalian cells [1,2], suggesting a common mechanism of toxicity by the action of hydrophobic xenobiotics on biomembranes.
(12) Previous studies in this laboratory with particulate Mn3O4 have shown that preweanling rats have substantially higher tissue Mn concentrations than similarly treated adults, indicating possible differences in uptake or elimination or both.
(13) Charge data from the target hospital showed a statistically significant reduction in laboratory charges per patient in the quarter following program initiation (P = 0.02) and no evidence for change in a group of five comparison hospitals.
(14) This new protocol has increased the effectiveness of the toxicology laboratory and enhanced the efficiency of the house staff.
(15) Whole-virus vaccines prepared by Merck Sharp and Dohme (West Point, Pa.) and Merrell-National Laboratories (Cincinnati, Ohio) and subunit vaccines prepared by Parke, Davis and Company (Detroit, Mich.) and Wyeth Laboratories (Philadelphia, Pa.) were given intramuscularly in concentrations of 800, 400, or 200 chick cell-agglutinating units per dose.
(16) Regression analysis on the 21 clinical or laboratory parameters studied showed that the only variable independently associated with CSF-FN was the total protein concentration in the CSF; this, however, explained only 14% of the observed variation in the CSF-FN concentration and did not show any correlation with CNS involvement.
(17) These tumors may nonetheless be etiologically related as indicated by the pattern of laboratory abnormalities, especially immunologic, in affected as well as unaffected members.
(18) There are several common clinical signs which should alert the physician to a possible diagnosis of SLE and which should condition him to look for specific clinical and laboratory findings.
(19) The authors describe the special medical expertise of the psychiatrist and define 11 indicators, such as a patient's need for new psychotropic medication or the presence of symptoms requiring medical or laboratory procedures, that can be used to determine whether psychiatric expertise is needed.
(20) A bouncy function has now been incorporated into a knee of the semi-automatic knee lock design in a pilot laboratory trial involving six patients.