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961.
PH Elzer MD Edmonds SD Hagius JV Walker MJ Gilsdorf DS Davis 《Canadian Metallurgical Quarterly》1998,34(4):825-829
We compared the efficacy of two clinically available drugs with N-methyl-D-aspartate receptor antagonist properties, dextromethorphan and ketamine, in potentiating morphine-induced antinociception. Ketamine alone at 0.3-3 mg/kg had no effect on the hot plate test and at 10 mg/kg caused sedation/motor deficits. The antinociceptive effect of 5 mg/kg morphine was slightly enhanced by 1 mg/kg, but not 0.3 or 3 mg/kg, ketamine. Dextromethorphan alone at 45 mg/kg had no effect, but at 60 mg/kg caused sedation/motor deficit. At 15-45 mg/kg, dextromethorphan significantly and dose-dependently increased the magnitude and duration of morphine-induced antinociception. Dextromethorphan also potentiated morphine at doses that, by themselves, did not cause antinociception (1-2 mg/kg). Implications: Dextromethorphan was more effective than ketamine in potentiating morphine-induced antinociception. Dextromethorphan may thus be the drug of choice for testing the interactions between N-methyl-D-aspartate antagonists and morphine clinically. 相似文献
962.
PURPOSE: To develop a hepatic artery embolization protocol and investigate its efficacy in a prospective study treating patients with hereditary hemorrhagic telangiectasia and predominant hepatic involvement. MATERIALS AND METHODS: One man and four women with hereditary hemorrhagic telangiectasia presented with symptoms of high-output heart failure, abdominal angina, or severe portal hypertension. The hepatic arteries were embolized in stages in three to five sessions at 1- to 15-week intervals. After peripheral embolization with polyvinyl alcohol particles, proximal arteries were embolized with coils. Computed tomography and assessment of cardiac output were performed before and after therapy and at the end of follow-up (median, 25 months; range, 12-55 months). RESULTS: After embolization, analgesics and antiemetics were necessary for a median of 5 and 2 days, respectively. Other than ischemic cholangitis (one patient), no complications were observed. The mean cardiac output decreased significantly (P < .05) from 14.2 L/min to 8.0 L/min. Symptoms of high-output heart failure, abdominal angina, and portal hypertension resolved in all patients. Seven months after embolization, one patient died of postoperative sepsis after an unsuccessful surgical attempt to create a portacaval shunt. Delayed recurrence of symptoms was not noted in the other patients. CONCLUSION: In symptomatic patients with hereditary hemorrhagic telangiectasia and predominant hepatic involvement, embolization of the hepatic arteries in stages is well tolerated by the patients and results in good clinical improvement at midterm follow-up. 相似文献
963.
R Gilliland DF Altomare H Moreira L Oliveira JE Gilliland SD Wexner 《Canadian Metallurgical Quarterly》1998,41(12):1516-1522
PURPOSE: This study assessed the efficacy of anterior overlapping sphincteroplasty and parameters predictive of a successful outcome. METHODS: Clinical findings and physiologic investigations of female patients who underwent anterior overlapping sphincteroplasty for fecal incontinence between 1988 and 1996 were reviewed. The extent of sphincter damage was assessed at needle electromyography as the number of quadrants exhibiting decreased motor unit potentials. Prolonged pudendal nerve terminal motor latencies were those of greater than 2.2 ms. The size of the endoanal ultrasound defect was assessed as degrees circumference of the external sphincter in which viable muscle was absent. Patients were reviewed by telephone questionnaire and were asked to grade the outcome of their surgery as excellent or good (success) or fair or poor (failure). Incontinence was graded using a scoring system of 0 (perfect continence) to 20 (complete incontinence). RESULTS: There were 100 patients who had an overlapping sphincteroplasty; complete follow-tip information was obtained for 77 patients at a median of 24 (range, 2-96) months. The median age was 47 (range, 25-80) years and they had a median duration of incontinence of four (range, 0.1-39) years. Prior sphincteroplasty had been performed in 30 patients with a median of one (range, 1-7) operations. Investigations performed included electromyography (n = 49), pudendal nerve terminal motor latency (n = 71), endoanal ultrasound (n = 49), and manometry (n = 67). Sixty percent of patients had improved continence and 42 (55 percent) considered their surgery to have been successful as attested to by a significant decrease in their incontinence score (from 15.1 +/- 4.5 to 4.3 +/- 4.2; P < 0.0001). Neither patient age, parity, prior sphincteroplasty, cause or duration of incontinence, extent of electromyography damage, size of the endoanal ultrasound defect, nor any manometric parameter correlated with outcome. However, 62 percent of 59 patients with bilaterally normal pudendal nerve terminal motor latencies had a successful outcome compared with only 16.7 percent of 12 patients with unilateral or bilateral prolonged pudendal nerve terminal motor latencies (P < 0.01). CONCLUSION: Bilateral normal pudendal nerve terminal motor latencies are the only factors predictive of long-term success after overlapping sphincteroplasty. 相似文献
964.
Thiazide-based diuretics are included in the list of banned drugs in the horse-racing industry. One effect of their misuse is increased urine flow, contributing to dilution of other doping agents. Their determination is essential in ensuring compliance to horse-racing regulation. This study evaluates the feasibility of using liquid chromatography/mass spectrometry (LC/MS) with electrospray and atmospheric pressure chemical ionization interfaces to analyze thiazidic diuretics in equine urine samples. Existing LC and gas chromatography/MS methods are limited in their applicability to thiazide analysis. Sample preparation, analyte extraction, chromatographic separation, ion-source collision induced dissociation, solvent composition, ionization mode, and ion polarity are discussed. The practicality of LC/MS for this analysis is demonstrated with actual equine administration samples collected at specified time intervals. Detection limits were 270 ng/mL for chlorothiazide, 131 ng/mL for hydrochlorothiazide, and 384 ng/mL for trichlormethiazide. 相似文献
965.
RP Oliveira NE Broude AM Macedo CR Cantor CL Smith SD Pena 《Canadian Metallurgical Quarterly》1998,95(7):3776-3780
We describe here the identification of eight polymorphic microsatellite loci with (CA)n repeats in the Trypanosoma cruzi genome based on the affinity capture of fragments using biotinylated (CA)12 attached to streptavidin-coated magnetic beads. The presence of two peaks in PCR amplification products from individual clones confirmed that T. cruzi is diploid. Hardy-Weinberg and linkage disequilibrium analyses suggested that sexual reproduction is rare or absent and that the population structure is clonal. Several strains, especially those isolated from nonhuman sources, showed more than two alleles in many loci demonstrating that they were multiclonal. The phylogenetic analysis of T. cruzi based on microsatellites revealed a great genetic distance among strains, although the strain dispersion profile in the Wagner network was in general agreement with the species dimorphism found by PCR amplification of the divergent region of the rRNA 24Salpha gene. 相似文献
966.
A Anumanthan A Bensussan L Boumsell AD Christ RS Blumberg SD Voss AT Patel MJ Robertson LM Nadler GJ Freeman 《Canadian Metallurgical Quarterly》1998,161(6):2780-2790
Expression of the BY55 protein has been shown to be tightly associated with NK and CD8+ T lymphocytes with cytolytic effector activity. To determine the function of this protein, we molecularly cloned BY55 cDNA. The cDNA sequence predicts a cysteine-rich, glycosylphosphatidylinositol-anchored protein of 181 amino acids with a single Ig-like domain weakly homologous to killer inhibitory receptors. Reduction and carboxyamidomethylation of immunoprecipitated BY55 gave a band of 27 kDa, whereas reduction alone led to an 80-kDa species, suggesting that BY55 is a tightly disulfide-linked multimer. RNA blot analysis revealed BY55 mRNAs of 1.5 and 1.6 kb whose expression was highly restricted to NK and T cells. BY55 was expressed on the CD56dim, CD16+ subset of NK cells, which have high cytolytic activity, but was not expressed and was not induced on the CD56bright, CD16-subset of NK cells, a subset with high proliferative, but low cytolytic, capacity. In human tissues, BY55 mRNA was expressed only in spleen, PBL, and small intestine (in gut lymphocytes). BY55 was expressed on all intestinal intraepithelial lymphocytes, which were predominantly CD3+TCRalpha/beta+CD4-CD8+CD11b+CD28-CD45RO+C D56-CD101+CD103+ (alphaEbeta7 integrin). In addition, BY55 was expressed on most CD8+CD28- peripheral blood T cells. These phenotypic relationships suggest that CD8+CD28+ precursor CTL may terminally differentiate into CD8+CD28-BY55+ effector CTL and that some of the peripheral blood CD8+CD28- subset may represent recirculation from mucosal epithelial immune sites. 相似文献
967.
CDNA clones encoding the rat DNA topoisomerase II were isolated from rat testis CDNA library using a DNA probe synthesized by two sequential nested PCRs. The nucleotide sequence of the entire coding region and its deduced 1526 amino acid sequence showed that 80% nucleotides and 89% amino acids were identical with human HeLa DNA topoisomerase II gene (hTOP2). Approximately 1100 amino acids at the N-terminus shows 96.5% sequence identity, but C-terminus has only 65% homology. Rat DNA topoisomerase II gene (rTOP2) contains three functional domains responsible for ATPase activity, break-reunion activity, and complex stability and DNA binding activity like other eukaryotic TOP2. It also contains two putative nuclear targeting sequences and a leucine zipper motif and has highly charged species specific sequences at the C-terminus. 相似文献
968.
969.
970.
Perumal Karthikeyan S.SD. Elanchezhiyan Jayaram Preethi Kristy Talukdar Sankaran Meenakshi Chang Min Park 《Ceramics International》2021,47(1):732-739
With the advancement of modern industries and metropolitan areas, negative environmental impacts such as eutrophication have become serious issues obstructing the usage of water sources in many countries. In this study, two-dimensional (2D) MXene materials were employed for the adsorptive removal of phosphate and nitrate ions from waters. The adsorption parameters of the sorption system including reaction time, solution pH, background ions, and reusability, were evaluated in batch experiments. Material characterization techniques, including X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, thermal gravimetric analysis, Brunauer–Emmett–Teller analysis, and high-resolution transmission electron microscopy were performed. The mechanism of removing phosphate and nitrate was clearly described by various kinds of interactions such as electrostatic interactions, and the complexation was significant to elucidate the adsorption mechanism. The adsorption data for phosphate and nitrate update was determined using different isotherms and kinetic models. Reusability and field studies on the MXenes were also conducted. The above findings demonstrate that 2D MXenes could act as promising adsorbents for the elimination of toxic ions from water/wastewater. 相似文献