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171.
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VIu Kulikov VP Kaznacheev NG Kolosova LV Molchanova 《Canadian Metallurgical Quarterly》1976,82(9):1086-1088
Physiological concentration (10 units/ml) of heparin activates ascorbate-dependent lipid peroxidation of erythrocytes and reduces their stability in the citrate-phosphate buffer (pH 3.0). In a concentration of 100 units/ml heparin does not influence the thermal (62 degrees) oxidation of methyloleate. It follows that heparin is not direct prooxidant. 相似文献
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Chromosome replication has been analysed in four species of Chilocorus. In C. ORBUS Csy., C. tricyclus Smith, and C. hexacyclus Smith, centric regions of all chromosomes are last to replicate, preceded in order by heterochromatic arms and euchromatic arms. In C. stigma Say, very late replication of centric regions can be detected only in otherwise wholly euchromatic chromosomes (= monophasics); in chromosomes with one arm heterochromatic ( = disphasics), these arms are last to replicate. Based on pachytene bivalent morphology and chromosome banding patterns, and supported by autoradiographic data, models are presented for the general organisation of Chilocorus chromosomes. All chromosomes in the first three species are subdivided into euchromatic arm, centric heterochromatin, and either a second euchromatic are (monophasics) or a heterochromatic arm (diphasics). Chilocorus stigma diphasics apparently lack distinct centric organisation, and are therefore divided into euchromatic and heterochromatic arms only. 相似文献
176.
Various aspects of speech and language were compared, using psycholinguistic techniques, in a group of 15 depressed patients and 16 manic patients: lexical diversity, syntactical complexity, syntactical elements, and content analysis. Contrary to anticipation, the manic patients did not show more varied word choice or complexity of sentence structure than the depressives. In particular, they did not differ significantly in type-token ratio. The greatest difference was in syntactical elements, with manics using more action verbs, adjectives, and concrete nouns, while the depressed patients used more state of being verbs, modifying adverbs, first-person pronouns, and personal pronouns. When compared by content analysis, the manics used more words reflecting a concern with power and achievement. These results imply that depressive speech tends to be more vague and qualified and to show considerable self-preoccupation, while manic speech tends to be colorful and concrete and to show more concern with things than with people. 相似文献
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A microparticulate dosage form for a highly soluble drug, diltiazem hydrochloride, was formulated with Eudragit RS100 and RL100 using a novel dual polymer technique. A mixture of diltiazem with Eudragit RS100 (low water permeability) in acetone was coacervated into soft polymer microdrops, following which a mixture of diltiazem and RL100 (high water permeability) was added to produce microparticles consisting of both polymers with diltiazem dispersed in the matrix. A second formulation was developed using the same method except using Eudragit RS100 for both steps. For a comparative study, diltiazem, Eudragit RS100 and RL100 were combined together in a single matrix and formulated into microparticles. In vitro drug release profiles using USP paddle dissolution apparatus 2 revealed that dual polymer matrix microparticles containing Eudragit RS100 in the inner and Eudragit RL100 in the outer core exhibit a suitable release profile with an initial release of the drug followed by a plateau level for the test period of 5 h. Differential scanning calorimetric analysis showed no interaction of the drug with the polymers. 相似文献
179.
NG Poythress SK Hoge RJ Bonnie J Monahan M Eisenberg T Feucht-Haviar 《Canadian Metallurgical Quarterly》1998,26(2):215-222
Delta9-tetrahydrocannabinol (delta9-THC) elicits antinociception in rodents through the central CB1 cannabinoid receptor subtype. In addition. Delta9-THC stimulates the release of dynorphin-related peptides leading to kappa-opioid spinal antinociception. In this work we describe the effect of a mixture of thiorphan (a neutral endopeptidase EC3.4.24.11 inhibitor) and bestatin (an aminopeptidase inhibitor), administered i.c.v., on the antinociceptive effect of peripherally administered delta9-THC in mice. As in the case of morphine or DAMGO ([D-Ala2.N-Me-Phe4,Gly-ol]enkephalin), a mu-selective opioid receptor agonist, the mixture of enkephalin-degrading enzyme inhibitors also enhanced the antinociceptive effect of delta9-THC. This effect was blocked by the CB1 cannabinoid receptor antagonist, SR-141,716-A, as well as by naloxone. The kappa-opioid receptor antagonist nor-binaltorphimine, administered i.t., also antagonized the effect of this combination. Similar results were obtained with the mu-opioid receptor antagonist beta-funaltrexamine after i.c.v. administration. These results demonstrate the involvement of both mu-opioid supraspinal and kappa-opioid spinal receptors in the interaction of both opioid and cannabinoid systems regulating nociception in mice. 相似文献
180.
AS Cantrell P Engelhardt M H?gberg SR Jaskunas NG Johansson CL Jordan J Kangasmets? MD Kinnick P Lind JM Morin MA Muesing R Noreén B Oberg P Pranc C Sahlberg RJ Ternansky RT Vasileff L Vrang SJ West H Zhang 《Canadian Metallurgical Quarterly》1996,39(21):4261-4274
Phenylethylthiazolylthiourea (PETT) derivatives have been identified as a new series of non-nucleoside inhibitors of HIV-1 RT. Structure-activity relationship studies of this class of compounds resulted in the identification of N-[2-(2-pyridyl)ethyl]-N'-[2-(5-bromopyridyl)]-thiourea hydrochloride (trovirdine; LY300046.HCl) as a highly potent anti-HIV-1 agent. Trovirdine is currently in phase one clinical trials for potential use in the treatment of AIDS. Extension of these structure-activity relationship studies to identify additional compounds in this series with improved properties is ongoing. A part of this work is described here. Replacement of the two aromatic moieties of the PETT compounds by various substituted or unsubstituted heteroaromatic rings was investigated. In addition, the effects of multiple substitution in the phenyl ring were also studied. The antiviral activities were determined on wild-type and constructed mutants of HIV-1 RT and on wild-type HIV-1 and mutant viruses derived thereof, Ile100 and Cys181, in cell culture assays. Some selected compounds were determined on double-mutant viruses, HIV-1 (Ile 100/Asn103) and HIV-1 (Ile100/Cys181). A number of highly potent analogs were synthesized. These compounds displayed IC50's against wild-type RT between 0.6 and 5 nM. In cell culture, these agents inhibited wild-type HIV-1 with ED50's between 1 and 5 nM in MT-4 cells. In addition, these derivatives inhibited mutant HIV-1 RT (Ile 100) with IC50's between 20 and 50 nM and mutant HIV-1 RT (Cys 181) with IC50's between 4 and 10 nM, and in cell culture they inhibited mutant HIV-1 (Ile100) with ED50's between 9 and 100 nM and mutant HIV-1 (Cys181) with ED50's between 3 and 20 nM. 相似文献