What's the difference between crystalline and urethane?

Crystalline


Definition:

  • (a.) Consisting, or made, of crystal.
  • (a.) Formed by crystallization; like crystal in texture.
  • (a.) Imperfectly crystallized; as, granite is only crystalline, while quartz crystal is perfectly crystallized.
  • (a.) Fig.: Resembling crystal; pure; transparent; pellucid.
  • (n.) A crystalline substance.
  • (n.) See Aniline.

Example Sentences:

  • (1) In addition to the phase diagrams reported here for these two binary mixtures, a brief theoretical discussion is given of other possible phase diagrams that may be appropriate to other lipid mixtures with particular consideration given to the problem of crystalline phases of different structures and the possible occurrence of second-order phase transitions in these mixtures.
  • (2) In 0.17 M Na+(aq), tRNA(Phe) exists in its native conformation and the number of strong binding sites (Ka greater than or equal to 10(4)) was estimated to be 3-4 by titration experiments, in agreement with X-ray structural data for crystalline tRNA(Phe) (Jack et al., 1977).
  • (3) Electron microscopy revealed the presence of a hitherto unreported peculiar "pilovacuolar" inclusion in numerous mitochondria, composed of an electron dense pile or rod within a vacuole, while globular or crystalline inclusions were absent.
  • (4) The advantages of the incision through the pars plana ciliaris are (1) easier approach to the vitreous cavity, (2) preservation of the crystalline lens and an intact iris, and (3) circumvention of the corneal and chamber angle complications sometimes associated with the transcorneal approach.
  • (5) These two crystallins were compared with respect to their native molecular masses, subunit structures, peptide mapping and amino acid compositions in order to establish the identity of each crystallin.
  • (6) Freeze-dried mannitol preparations were shown to be of a crystalline nature.
  • (7) Antigenic properties of crystalline pepsin, trypsin and chymotrypsin were studied in 9 rabbits immunised with these enzymes.
  • (8) X-ray diffraction spectrum of 1:8 coprecipitate (COPPT) showed no crystalline structure of AD.
  • (9) However, significant differences in the formation and melting of the highly crystalline phase were evident between the two polar headgroup stereoisomers.
  • (10) Degradation studies of the crystalline antibiotic, m.p.
  • (11) Crystalline derivatives of the amino sugar i. e. methyleremosaminide and methyl-N,O-acetyleremosaminide (alpha- and beta-anomers) were prepared.
  • (12) A systematic structural comparison of several carp gamma-crystallins with high methionine contents was made by the secondary-structure prediction together with computer model-building based on the established X-ray structure of calf gamma-II crystallin.
  • (13) The lens cell-free system synthesizes in addition to the crystallins, polypeptides which co-electrophorese with lens plasma membrane protein components.
  • (14) Arrhenius plots of the leakage rates showed breaks in the 20-25 degrees C temperature range, which correspond to the gel-liquid crystalline phase transition of the target liposomes.
  • (15) These results suggest that ATP modulates the functional behavior of alpha-crystallin.
  • (16) Because anesthetics transform the solid-gel membrane into a liquid-crystalline state, and because phospholipid membranes display an anomaly in permeability at the phase transition, dimyristoylphosphatidylcholine vesicles were studied at temperatures above the main phase transition to avoid this anomaly.
  • (17) By monitoring the synthesis of specific lens crystallin proteins, and the morphological and cellular changes associated with this differentiated system, we have demonstrated a close correlation between statin expression and cell commitment to the G0 nonreplicative cell cycle state.
  • (18) Developmental regulation of crystallin protein synthesis was observed in rat lenses between embryonic day 19 and postnatal day 21.
  • (19) Bovine lens calf gamma-II crystallin contains five histidine residues at sequence positions 14, 53, 84, 117, and 122.
  • (20) A second crystalline material was observed within cells in the 15,000 X g pellet from spinal fluid.

Urethane


Definition:

  • (n.) A white crystalline substance, NH2.CO.OC2H5, produced by the action of ammonia on ethyl carbonate. It is used somewhat in medicine as a hypnotic. By extension, any one of the series of related substances of which urethane proper is the type.

Example Sentences:

  • (1) In urethane-anesthetized rabbits, IOP and blood pressure were lowered by intravenous administration of delta 9-THC but not by bolus cerebral administration.
  • (2) Chloralose-urethane is considered a suitable anaesthetic in rats when studying the effects of noradrenaline and guanethidine.
  • (3) Experiments were carried out under urethane anaesthesia.
  • (4) Urethane also produced a trend towards metabolic acidosis.
  • (5) Differential pulse voltammetry used in combination with an electrochemically treated carbon fiber electrode allowed the detection of 5-hydroxyindoles (5-HI) in the dorsal horn of the urethane-anesthetized rat.
  • (6) Seven or 14 days of treatment with the beta 2-adrenoceptor agonist clenbuterol, 0.3 mg kg-1, s.c., twice daily, increased the basal mean blood pressure in normotensive urethane-anaesthetized rats.
  • (7) To try to compare receptor compartment kinetics, receptor binding, and binding-response coupling for two smooth muscle types in vivo, pressor and uterine responses to oxypressin, an equipotent analog of oxytocin and vasopressin, were studied simultaneously in urethane-anesthetized, pentolinium-indomethacin treated rats.
  • (8) Single unit discharges in the ventromedial hypothalamic nucleus (VMH) and lateral hypothalamic area (LH) were extracellularly recorded in urethane anesthetised female rats, while various solutions were perfused through the stomach or duodenum via implanted polythene tubes.
  • (9) The role of the sympatho-adrenal system in the production of tachycardia accompanying the hypotensive response to hydralazine was studied in urethane-anesthetized rats subjected to previous bilateral adrenal demedullation or to pretreatment with 6-hydroxydopamine and compared with intact control animals.
  • (10) A germ line mutation causing a tumour ('tumour mutation') is weakly carcinogenic by itself, but it is strongly expressed in the progeny after postnatal treatment with a small dose of the carcinogenesis promoting agent urethane.
  • (11) Experiments were carried out on 36 urethane-chloralose aneasthesized, paralyzed, vagotomized and artificially ventilated rabbits.
  • (12) Fasting hyperglycemia was observed in urethane-anesthetized rats.
  • (13) Much evidence now exists which defines the ability of poly(ether)urethanes to selectively extract ions, especially calcium ion from solution.
  • (14) Filling of the gastric lumen of rats with 1.0 M NaCl solution (5 ml) for 10 min under urethane anesthesia caused an increase in the gastric fluid concentrations of prostaglandin (PG) E2, 13,14-dihydro-15-keto-PGE2 and 6-keto-PGF1 alpha as determined by radioimmunoassay.
  • (15) The effect of thyrotropin-releasing hormone (TRH) on the mechanism regulating growth hormone (GH) secretion was investigated in urethane-anesthetized male rats.
  • (16) In urethane-anesthetized rats, low frequency electrical stimulation of the thalamic radiation (TR) evoked an augmenting response in the somatosensory cortex (SCx) which was followed by rhythmic slow waves.
  • (17) The frequencies of transformations of primary human and Chinese hamster fibroblasts have been compared with the spontaneous and induced frequencies of mutation for resistance to thioguanine and ouabain, and for ability to use fructose, using the carcinogens benzo (alpha) pyrene and urethane.
  • (18) In urethane-anaesthetized rats clonidine was administered intravenously (i.v.
  • (19) One end of the spacer group was coupled to the derivatized surface through a urethane bond between the amine group of the spacer and the derivatized surface.
  • (20) These compounds were tested for anticarcinogenic activity against urethane-induced pulmonary adenomas and for antitumoral activity against some transplanted tumours such as leukemia L 1210, mammary adenocarcinoma Ca 755 and Walker carcinosarcoma 256.