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The involvement of excitatory amino acid (EAA) receptors in mediation of the toxic effects of cocaine was studied in male ICR mice. Cocaine HCl (90 mg/kg, IP) induced seizures in 95% and death within 24 h in 68% (n = 135) of the animals. There was a significant correlation (r = .54) between the time to onset of convulsions and the time to death in mice which died within 30 min of injection (n = 84). Pretreatment with selected EAA receptor antagonists 15 min prior to cocaine differentially blocked cocaine toxicity. Selective N-methyl-D-aspartic acid (NMDA) receptor antagonists (MK-801, dextrorphan, CPP) decreased both the incidence of seizures and mortality. A nonselective EAA antagonist, kynurenic acid, decreased lethality in doses which did not reduce convulsions. A similar action was observed following pretreatment with the selective kainic acid/AMPA receptor antagonist, GDEE. Antagonists at EAA receptors can provide significant protection against cocaine-induced toxicity. Moreover, the data provide evidence for the involvement of both NMDA and non-NMDA receptor subtypes in aspects of cocaine toxicity. 相似文献
3.
Berrin Leblebici Nur Turhan Mehmet Adam Mahmut Nafiz Akman 《Journal of wound, ostomy, and continence nursing》2007,34(4):407-411
OBJECTIVE: We sought to measure the incidence of pressure ulcer development at a university health center in Turkey, and to determine whether the Waterlow Pressure Sore Risk (PSR) Scale score predicted pressure ulcer development, stage, or number of ulcers. DESIGN: We prospectively evaluated patients who were hospitalized at our university-based medical center. SETTING AND SUBJECTS: We analyzed data from 22,834 patients hospitalized at the Baskent University Adana Teaching and Medical Research Center in Ankara, Turkey from January 1, 2004 to December 31, 2004, including 360 patients who developed pressure ulcers. INSTRUMENTS: The Waterlow PSR Scale was used to assess pressure ulcer risk. In addition, age, sex, the ward or unit in which the patient was hospitalized, reason for hospitalization, and location and stage of ulcers were collected on a data form designed specifically for this study. METHODS: A single nurse physiotherapist assessed all patients daily during their hospitalization. When a pressure ulcer was diagnosed by the nurse physiotherapist, a physician staged the pressure ulcers based on the US National Pressure Ulcer Advisory Panel (NPUAP) staging system. RESULTS: Three hundred sixty out of 22,834 patients developed 1 or more pressure ulcers, resulting in an incidence rate of 1.6%. Most ulcers (59.2%) occurred in patients hospitalized in the intensive care unit (n = 213). A positive correlation between the Waterlow PSR Scale score and number of ulcers per patient (r: 0.178, P < .01) was identified. No significant correlation was found linking Waterlow PSR Scale score and ulcer stage or the development of a single ulcer. CONCLUSION: We found significantly lower pressure ulcer incidence rates than those commonly reported in the literature, which we believe is principally attributable to short hospital stays and a strong emphasis on preventive nursing care. While high Waterlow PSR scale Scores correlated positively with development of multiple ulcers, this did not predict ulcer stage or the presence of a single pressure ulcer. 相似文献
4.
J H Doroshow M Bertrand E Newman P Multhauf L Leong D Blayney D Goldberg K Margolin B Carr S Akman 《NCI monographs : a publication of the National Cancer Institute》1987,(5):171-174
In this study, 50 patients were randomly assigned to treatment with 5-fluorouracil (FUra) or FUra plus high-dose continuous-infusion folinic acid. Five of 27 evaluable patients in the FUra group versus 10 of 21 patients in the FUra plus folinic acid arm of the study had objective partial remissions, P = 0.02. Time to progression was 3.9 months for FUra and 8.0 months for FUra and folinic acid, P = 0.006; however, median survivals (11.9 versus 14.5 months) were not different in this crossover study. Toxicity in both treatment arms was mild, although patients receiving FUra plus folinic acid experienced significantly more stomatitis than patients treated with FUra alone. This study suggests that high-dose, continuous-infusion folinic acid, which produces a steady-state level of biologically active folates of 10 microM, significantly increases the therapeutic activity of FUra. 相似文献
5.
Akman MA Erden HF Tosun SB Bayazit N Aksoy E Bahceci M 《Human reproduction (Oxford, England)》2001,16(5):868-870
The management of poor responders in IVF has always been a big problem. The ideal approach has yet to be formulated. In this study we aim to compare two alternative stimulation protocols. A total of 48 poor responder patients described from previous cycles were included and grouped into two: group I consisted of 24 patients in 24 cycles in which leuprolide acetate (40 microg s.c. per day) was initiated on cycle day 2 followed by exogenous gonadotrophins on cycle day 3; group II consisted of 24 patients in 24 cycles in which ovarian stimulation included gonadotrophin-releasing hormone (GnRH) antagonist (cetrorelix, 0.25 mg daily during late follicular phase) administration. While only the oestradiol concentrations on the day of HCG were lower in group II compared with group I, the clinical pregnancy and implantation rates among groups did not show any significance. The impact of these two regimens in ovarian stimulation of poor responders seem to be same and to establish these results further randomized studies with larger sample sizes are required. 相似文献
6.
Screening of SLC26A4 (PDS) gene in Pendred's syndrome: a large spectrum of mutations in France and phenotypic heterogeneity 总被引:4,自引:0,他引:4
Blons H Feldmann D Duval V Messaz O Denoyelle F Loundon N Sergout-Allaoui A Houang M Duriez F Lacombe D Delobel B Leman J Catros H Journel H Drouin-Garraud V Obstoy MF Toutain A Oden S Toublanc JE Couderc R Petit C Garabédian EN Marlin S 《Clinical genetics》2004,66(4):333-340
Sensorineural hearing defect and goiter are common features of Pendred's syndrome. The clinical diagnosis of Pendred's syndrome remains difficult because of the lack of sensitivity and specificity of the thyroid signs. The identification of PDS as the causative gene allowed molecular screening and enabled a re-evaluation of the syndrome to identify potential diagnostic characteristics. This report presents the clinical and genotypic findings of 30 French families, for whom a diagnosis of Pendred's syndrome had been made. Twenty-seven families had at least one mutated allele. Twenty-eight different mutations were identified, 11 of which had never been previously reported. The main clinical characteristics were: early hearing loss, fluctuation in terms of during deafness evolution, and the presence of an enlarged vestibular aqueduct. 相似文献
7.
Biological Activity of Sch 14342, an Aminoglycoside Antibiotic Coproduced in the Gentamicin Fermentation 总被引:3,自引:2,他引:1 下载免费PDF全文
J. A. Waitz E. L. Moss Jr. E. M. Oden G. H. Wagman M. J. Weinstein 《Antimicrobial agents and chemotherapy》1972,2(6):464-469
Sch 14342 is an aminoglycoside antibiotic coproduced as a minor component in the gentamicin fermentation. Sch 14342 was found to have the same antibacterial spectrum as gentamicin in vitro and in vivo, and was approximately one-third as active in mouse protection tests. Sch 14342 relative to gentamicin was one-third as toxic in acute tests in mice, one-eighth as toxic in renal toxicity tests in dogs, and an estimated one-tenth as toxic in cat ataxia tests. Sch 14342 possesses a significantly improved therapeutic index relative to gentamicin with reference to ataxia potential and renal toxicity. 相似文献
8.
Akman Steven A.; Kensler Thomas W.; Doroshow James H.; Dizdaroglu Miral 《Carcinogenesis》1993,14(9):1971-1974
The mouse skin tumor promoter benzoyl peroxide (BzPO), in conjunctionwith Cu(I), causes promutagenic damage in DNA. Because freeradical intermediates are produced by the reaction of BzPO withCu(I), we sought to determine whether BzPO plus Cu(I) causedDNA base damage typical of that caused by the hydroxyl radical.A broad range of modified DNA bases were measured by GC-MS withselected-ion monitoring after exposure of purified plasmid pCMVßgalDNA to BzPO ± Cu(I). Exposure to BzPO/Cu(I) caused upto 20-fold increases in the levels of adenine-derived modifiedbases, and only a <2-fold increase in thymine-derived modifiedbases. The guanine-derived modified base 8-hydroxyguanine waselevated to the highest net amount, 160 molecules/105 DNA bases.Exposure to BzPO alone or Cu(I) alone induced only minor (<<2-fold) DNA base modification. Also, benzoic acid, the majornon-radical metabolite of BzPO, or BzPO plus Fe(II) were ineffectiveat inducing DNA base modification. The hydroxyl radical scavengerdimethyl sulfoxide inhibited BzPO/Cu(I)-induced base modificationby 1050%. These data suggest that the reaction of BzPOwith Cu(I) generates hydroxyl radical or a similarly reactiveintermediate which causes DNA base damage. This damage may beresponsible for BzPO/Cu(I) mediated mutagenesis. 相似文献
9.
Objective Familial Mediterranean fever (FMF) is an autosomal recessive recurrent polyserositis with a higher prevalence in some ethnic groups, including Turks. Mutations in the FMF gene (MEFV) were found associated with FMF. The aim of this study was to analyze MEFV gene mutations in FMF patients to gain insight into the mutation phenotype correlation.Objectives We analyzed the most frequent mutations (M680I, M694V, V726A, and E148Q) in a group of young male Turkish FMF patients using an amplification refractory mutation system and a commercial kit.Results M694V mutation was detected in 80% of the patients. After making a strict diagnostic discrimination between arthralgia and arthritis, arthritis was present in 71% of homozygous and 29.4% of heterozygous patients for M694V mutation. Other mutations were not found to correlate with specific symptoms or findings.Conclusion The homozygosity of M694V mutation in the MEFV gene is associated with arthritis in FMF patients. 相似文献
10.