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BACKGROUND AND PURPOSE: Marine luminous bacteria were isolated and identified from samples in shallow coastal waters of Taiwan during the relatively warm seasons. METHODS: Identification of the luminous isolates was performed based on differences of phenotypic and genotypic characteristics together with data from phylogenetic analysis. RESULTS: Twenty seven strains of marine luminous bacteria were isolated. They were divided into five types based on differences of phenotypic characteristics. However, they could be clustered into only two genotypes according to the analysis of restriction patterns of polymerase chain reaction-amplified 16S rRNA genes digested with various restriction enzymes. The characterization data together with the 16S rRNA gene-based phylogenetic analysis revealed that the isolates included in phenotype I (seven isolates) could be Photobacterium leiognathi, and those included in phenotypes II-V (twenty isolates) might be classified as Vibrio harveyi. However, phylogeny based on gyrB sequences indicated that phenotypes II-V could be classified into two species, V. harveyi and Vibrio campbellii. CONCLUSION: Culturable luminous bacteria in the shallow coastal waters of Taiwan during the sampling period are dominated by V. harveyi/campbellii and P. leiognathi, and the former species appeared to be more prevalent and numerous than the latter species in general.  相似文献   
83.
Background: Although opioids are unsurpassed analgesics, experimental and clinical studies suggest that opioids activate N-methyl-d-aspartate pronociceptive systems leading to pain hypersensitivity and short-term tolerance. Because it is difficult in humans to differentiate pain from hyperalgesia during the postoperative period, the authors performed experimental studies with fentanyl using the rat incisional pain model for evaluating relations between hyperalgesia and short-term tolerance. Because N-methyl-d-aspartate receptor antagonists oppose both pain hypersensitivity and tolerance induced by opioids, the authors examined the capability of ketamine for improving exaggerated postoperative pain management.

Methods: During halothane anesthesia, a hind paw plantar incision was performed in rats receiving four fentanyl subcutaneous injections (100 [mu]g/kg per injection, every 15 min). In some groups, three subcutaneous ketamine injections (10 mg/kg per injection, every 5 h) were performed in saline- or fentanyl-treated rats. One day after surgery, the analgesic effect of morphine (2 mg/kg subcutaneous) was tested. Analgesia, mechanical hyperalgesia, tactile allodynia, and pain score were assessed for several days using the paw pressure vocalization test, the von Frey application test, and the postural disequilibrium test.

Results: Fentanyl induced analgesia but also produced exaggerated postoperative pain as indicated by the enhancement of hyperalgesia, allodynia, and weight-bearing decrease after hind paw plantar incision. Ketamine pretreatment prevented such a fentanyl-induced enhancement of postoperative pain and improved its management by morphine.  相似文献   

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The aim of this study was to detect salvageable peri-infarction myocardium by MRI in rats after infarction, using with a double contrast agent (CA) protocol at 7 Tesla. Intravascular superparamagnetic iron oxide (SPIO) nanoparticles and an extracellular paramagnetic CA (Gd-DOTA) were used to characterize the peri-infarction zone, which may recover function after reperfusion occurs. Infarcted areas measured from T1-weighted (T1-w) images post Gd-DOTA administration were overestimated compared to histological TTC staining (52% +/- 3% of LV surface area vs. 40% +/- 3%, P=0.03) or to T2-w images post SPIO administration (41% +/- 4%, P=0.04), whereas areas measured from T2-w images post SPIO administration were not significantly different from those measured histologically (P=0.7). Viable and nonviable myocardium portions of ischemically injured myocardium were enhanced after diffusive Gd-DOTA injection. The subsequent injection of vascular SPIO nanoparticles enables the discrimination of viable peri-infarction regions by specifically altering the signal of the still-vascularized myocardium.  相似文献   
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Editorial     
Coulom  Pierre 《Acta endoscopica》2002,32(1):II-II
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Poly(oxyethylene)s with dithioster end groups were obtained from mono- and dihydroxyl terminated commercial polymers by reaction with dimethyl chloroacetamide, subsequent thionation of the amide group, and usual conversion of the thioamides into the dithioesters 14, 15 and 20, 21 . The best results were obtained in the syntheses of the S-carboxymethyl dithioesters ( 15 and 21 ). The resulting reactive poly(oxyethylene)s were grafted upon silica tubes and electrophoresis cells, previously activated by aminopropylsilanization. These graftings result in lowering of the surface potential of the tubes and in suppression of the electro-osmosis flow in an electrophoresis cell tested with a TiO2 standard sample.  相似文献   
90.
Although several studies have demonstrated the efficacy of subcutaneous immunotherapy in allergic asthma, few have shown the same benefit using sublingual immunotherapy (SLIT) in asthmatic patients. This study was conducted to assess the efficacy of house dust mite (HDM) SLIT in addition to allergen avoidance and standard pharmacologic treatment. A double-blind, placebo-controlled trial was performed in 111 children (aged 5-15 yr) with HDM-induced mild-to-moderate asthma. After a 4-week baseline phase, patients were randomly assigned to receive SLIT with tablets of HDM extract (n = 55) or placebo (n = 56) for 18 months. Pharmacologic treatment was adjusted every 3 months following a step-down approach. Asthma symptom scores, reduction in use of inhaled corticosteroids and inhaled beta(2)-agonists, rhinitis symptoms, lung function tests, skin sensitivity to HDM, dust mite-specific immunoglobulin (Ig) E and IgG(4), and quality of life (QoL) were assessed during the study. After 18 months of treatment, diurnal and nocturnal asthma symptoms scores did not show significant differences between SLIT and placebo groups. Inhaled corticosteroids and inhaled beta(2)-agonists use was reduced in both groups without significant differences between groups. There were no significant differences in lung function (forced expiratory volume in 1 s and peak flow rate variations) between groups. Rhinitis symptom score decreased in both groups, with no difference between the two groups. The severity dimension of QoL was significantly improved in the SLIT group (age 6-12 yr). SLIT induced a significant reduction of skin sensitivity to HDM (p < 0.01) and a significant increase in HDM-specific IgE and IgG(4) antibodies (p < 0.001) in the SLIT group compared with the placebo group. SLIT was well tolerated with mild/moderate local adverse events. No severe systemic reactions were reported. This study indicates that, when mild-moderate asthmatic children are optimally controlled by pharmacologic treatment and HDM avoidance, SLIT does not provide additional benefit, despite a significant reduction in allergic response to HDM. Under such conditions, only a complete, but ethically unfeasible, discontinuation of inhaled corticosteroid would have demonstrated a possible benefit of SLIT.  相似文献   
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