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OBJECTIVES: To examine whether peripheral burn injury in rats elevates prostaglandin E2 in the central nervous system and to determine where in the central nervous system enzymes responsible for prostaglandin E2 synthesis are expressed. DESIGN: Prospective controlled animal study. SETTING: University research laboratory. SUBJECTS: Sprague-Dawley rats. INTERVENTIONS: Rats received either approximately 25% full-thickness burn injury or sham treatment. At 36 hrs after the injury, the cerebrospinal fluid was sampled to measure prostaglandin E2, and the brain and the spinal cord were sampled for immunohistochemical detection of cyclooxygenase-2 and microsomal-type prostaglandin E2 synthase, enzymes that are responsible for prostaglandin E2 production. MEASUREMENTS AND MAIN RESULTS: The prostaglandin E2 concentration in the cerebrospinal fluid was significantly elevated in the injured rats, and this elevation was suppressed by a cyclooxygenase-2-specific inhibitor, NS398. Only in the injured rats, cyclooxygenase-2 and microsomal-type prostaglandin E synthase proteins were detected in vascular endothelial cells throughout the central nervous system with no regional difference. A double-immunofluorescence study revealed that cyclooxygenase-2 and microsomal-type prostaglandin E synthase were coexpressed in the perinuclear region of the endothelial cells. CONCLUSIONS: These results indicate that peripheral burn injury induces cyclooxygenase-2 and microsomal-type prostaglandin E synthase in endothelial cells of the central nervous system. These enzymes likely elevate the cerebrospinal fluid concentration of prostaglandin E2, a prostanoid that, in turn, activates prostaglandin E2 receptors on the central nervous system neurons involved in the general symptoms following burn injury.  相似文献   
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We compared neural activation detected by magnetoencephalography (MEG) during tactile presentation of words and non-words in a postlingually deaf-blind subject and six normal volunteers. The left postcentral gyrus, bilateral inferior frontal gyri, left posterior temporal lobe, right anterior temporal lobe, bilateral middle occipital gyri were activated when tactile words were presented to the right hand of the deaf-blind subject. This set of activated regions was not observed in the normal volunteers, although activation of several combinations of these regions was detected. Positron emission tomography confirmed the location of the MEG-activated areas in the deaf-blind subject. Our results demonstrated that the deaf-blind subject is heavily involved in interpreting tactile language by enhancing cortical activation of cognitive and semantic processing.  相似文献   
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BACKGROUND: Although it is well known that a no-smoking policy can reduce smoking rate among hospital employees, the effect of this policy on patients' smoking behavior has not been examined. METHODS: Starting on the world no-tobacco day in 2001, the Sakai Municipal Hospital changed partial no-smoking policy into complete no-smoking policy. In this study, we examined the effect of this policy change on patients' smoking status during preoperative period. At preoperative visit, we asked a patient a change of smoking status during preoperative period. The change of patients' smoking status was compared between before and after coming into effect of no-smoking policy. RESULTS: Smoking rates at first visit to out-patient clinic of each surgical department before and after coming into effect of no-smoking policy were 35.6%(36/101) and 41.8%(28/67), respectively (P=0.317). Among these smokers, smoking cessation rates at preoperative visit before and after coming into effect of no-smoking policy were 44.4%(16/36) and 75.0%(21/28), respectively (P=0.014). CONCLUSIONS: The hospital no-smoking policy has a strong effect on improvement of patients' smoking behavior during preoperative period.  相似文献   
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The design of polymer microcarrier surfaces for enhanced cell growth   总被引:1,自引:0,他引:1  
A variety of neutral and cationic polymers based on polyamino acids were prepared and investigated as microcarriers for cell attachment and growth. Among neutral polymer particles including the alkylated poly(gamma-methyl L-glutamate) (PG) particles, in which the hydrophobicity changes as a function of the length of the alkyl groups, and hydroxy terminal PG particles, the PG particle with the longest alkyl chain (PG-C12) demonstrated the highest cell attachment rate and highest rate of cell growth. Moreover, the introduction of hydroxyl groups (PG-OH) led to a deterioration of cell growth. Cell growth on cationic particles having primary amino groups was drastically dependent upon the anion exchange capacity (AEC). A higher AEC for aminated PG microcarriers inhibited cell growth. In contrast, a higher AEC for cross-linked poly( epsilon -lysine) (PL) microcarriers facilitated cell growth. Cell growth on cationic particles clearly showed a good correlation with the pK(a,app) of the microcarriers, but not with their AEC. The particles with low and high pK(a) values possessed toxically acidic and basic pH microenvironments near the surface, respectively. These microenvironments had cytotoxic effects. On the other hand, no correlation between attachment rate constants and high cell growth was observed. The aminated particles, in which pK(a) were controlled at neutral pH, and PG-C12 produced obviously higher cell growth than did a commercially available microcarrier.  相似文献   
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TIN (ifosfamide 1.5 g/m2 daily for 3 days, paclitaxel 175 mg/m2, and nedaplatin 70 mg/m2 on day 1) was administered to patients with metastatic urothelial cancer previously treated by platinum-based chemotherapy and repeated every 4 weeks. Four patients received maintenance therapy, which consisted of 5'-DFUR 800 mg/day orally for 12 weeks and 1 subsequent course of TIN. This therapy regimen was repeated for 2 years from initiation of TIN. Eleven of 12 patients (91.6%) demonstrated a major response (3 complete responses, 8 partial responses), with durations of response ranging from 3 to 20 months. Progression-free survival time was from 0 to 20 months (median 8 months). One-year progression-free survival rate was 45.8%. Overall survival time was from 2 to 20 months (median 10.5 months). One-year overall survival rate was 53.5%. Grade 3/4 hematologic toxicity involved neutropenia in 100% and thrombocytopenia in 33.3%. Febrile neutropenia was observed in 5 patients (41.6%). Grade 3 nonhematologic toxicity involved malaise in 15.3%. No patient discontinued this therapy because of complications. TIN is a potent, well-tolerated regimen for previously treated patients with urothelial cancer.  相似文献   
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