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991.
992.
1. In the present study, we used a low dose of propofol (5 mg/kg per h) to investigate its effects on the pro-inflammatory cytokines (tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-10) and changes in nitric oxide (NO) following lipopolysaccharide (LPS) for a period of 12 h in conscious rats. 2. Experiments were designed to induce endotoxin shock by intravenous injection of Klebsiella pneumoniae LPS (10 mg/kg) in conscious rats. Arterial pressure (AP) and heart rate (HR) were monitored continuously for 12 h after LPS administration. Tumour necrosis factor-alpha, IL-1beta, IL-10 and plasma nitrates/nitrites were determined before and 0.5, 1, 3, 6, 9 and 12 h after LPS administration. A low dose of intravenous propofol (5 mg/kg per h) was administered to investigate the effects on cytokine responses and changes in NO in endotoxin shock. 3. Lipopolysaccharide significantly increased TNF-alpha, IL-1beta, IL-10, nitrites/nitrates and HR, whereas mean AP was decreased. Post-treatment with propofol suppressed the release of TNF-alpha, IL-1beta, IL-10 and NO production after endotoxin shock. 4. Lipopolysaccharide also caused a decrease in the white blood cell count and haematocrit. 5. Post-treatment with propofol slightly, but not significantly, affected the LPS-induced systemic hypotension, tachycardia, leukocytopenia and anaemia. 6. These findings suggest that low-dose propofol may be beneficial to the inflammatory change in sepsis.  相似文献   
993.
倍他乐克治疗慢性心力衰竭30例临床观察   总被引:1,自引:0,他引:1  
袁先琢  夏邦俊 《中国基层医药》2004,11(10):1190-1191
目的 探讨倍他乐克对慢性心力衰竭 (CHF)患者的治疗作用。方法 选取本院 2 0 0 1~ 2 0 0 3年收治的按NYHA分级为Ⅱ~Ⅲ级的CHF患者 6 2例 ,随机分为两组 ,对照组 ( 32例 )给予限盐、强心、利尿、扩血管、ACE Ⅰ联合应用 ,治疗组在对照组治疗的基础上添加倍他乐克治疗 ,分别观察并比较两组患者心功能改善情况、心率和血压治疗前后变化情况。结果 倍他乐克组总有效率为 93 3% ,对照组总有效率 75 % ,两组间差异有显著意义 ( χ2 =4 13,P <0 0 5 ) ,且其他指标均有改善。结论 倍他乐克对慢性心力衰竭有较好的治疗作用  相似文献   
994.
Please cite this paper as: Effect of topical application and intraperitoneal injection of oregonin on atopic dermatitis in NC/Nga mice. Experimental Dermatology 2010; 19 : e37–e43. Abstract: The diarylheptanoid, oregonin (ORE), which was isolated from the bark of Alnus japonica Steudel that grows natively in Korea, has been known to exert antioxidative, anti‐inflammatory, anti‐cancer and immune response inhibitory effects. The antioxidative effect of ORE was observed on the superoxide and 1,1‐diphenyl‐2‐picrylhydrazyl radical, as well as on the expression of inducible nitric oxide synthase and cyclooxygenase‐2 in lipopolysaccharide‐treated RAW264.7 macrophages. The statistically significant inhibitory action of ORE against production of cytokines induced by bacterial products or by interleukin (IL)‐1β, free radicals and nitrogen species, and a corresponding increase in cellular calcium concentration because of ORE were confirmed in bone marrow and spleen dendritic cells that are known to play important functions in the development and advancement of atopic dermatitis (AD). It was thus expected that ORE would exert a beneficial effect in the treatment of AD. A study on the pharmaceutical benefits of ORE against AD has not yet been conducted in vivo. We therefore used an in vivo AD animal model, namely the NC/Nga mice, and by applying ORE onto the animals through skin application as well as intraperitoneal injection, we attempted to evaluate the benefits of ORE in this system. Evaluation of ORE was conducted by following the SCORE method to score the effect, as well as by measuring the Th2 cytokines IL‐4, IL‐5 and IL‐13 levels from serum and lymphocytes, and IgE and eosinophil levels from serum. Additionally, the expression of mRNA and protein levels was estimated using real‐time polymerase chain reaction and Western blotting analysis. The following categories of clinical evaluation, Th2 cytokines IL‐4, IL‐5 and IL‐13 values, serum IgE levels, serum eosinophil levels, and mRNA and protein expression levels of iNOS and COX‐2, were evaluated from topical application and intraperitoneal injection groups of ORE. The effects of ORE on AD in NC/Nga mice were confirmed as being similar to the positive control group, while a significant difference with the negative control group was observed. The results presented in this report suggest that ORE might be beneficial in the treatment of AD.  相似文献   
995.
996.
Understanding and controlling of excited carrier dynamics is of fundamental and practical importance, particularly in photochemistry and solar energy applications. However, theory of energy relaxation of excited carriers is still in its early stage. Here, using ab initio molecular dynamics (MD) coupled with time-dependent density functional theory, we show a coverage-dependent energy transfer of photoexcited carriers in hydrogenated graphene, giving rise to distinctively different ion dynamics. Graphene with sparsely populated H is difficult to dissociate due to inefficient transfer of the excitation energy into kinetic energy of the H. In contrast, H can easily desorb from fully hydrogenated graphane. The key is to bring down the H antibonding state to the conduction band minimum as the band gap increases. These results can be contrasted to those of standard ground-state MD that predict H in the sparse case should be much less stable than that in fully hydrogenated graphane. Our findings thus signify the importance of carrying out explicit electronic dynamics in excited-state simulations.  相似文献   
997.
998.
In this study, we examined the in vivo osteogenic differentiation of human embryoid bodies (hEBs) by using an injectable in situ-forming hydrogel. A solution containing MPEG-b-(polycaprolactone-ran-polylactide) (MCL) and hEBs was easily prepared at room temperature. The MCL solution with hEBs and osteogenic factors was injected into nude mice and developed into in situ-forming hydrogels at the injection sites; these hydrogels maintained their shape even after 12 weeks in vivo, thereby indicating that the in situ-forming MCL hydrogel was a suitable scaffold for hEBs. The in vivo osteogenic differentiation was observed only in the in situ gel-forming MCL hydrogel in the presence of hEBs and osteogenic factors. In conclusion, this preliminary study suggests that hEBs and osteogenic factors embedded in an in situ-forming MCL hydrogel may provide numerous benefits as a noninvasive alternative for allogeneic tissue engineering applications.  相似文献   
999.
Background and Aim: Few systematic studies have been published on prognosis and clinical outcome of gastric cancer patients with disseminated intravascular coagulation (DIC) as the first presentation of malignancy. We evaluated the clinicopathologic features and clinical outcomes of this population. Methods: We reviewed the medical records of patients with metastatic or recurred gastric cancer that initially presented with DIC. Results: Twenty‐one patients were included. Median age was 47 years (range, 24–72 years). Eighteen patients (85.7%) had bone metastasis, and nine patients (42.9%) had hemorrhagic complication of DIC. Fourteen patients received palliative chemotherapy, and seven patients received best supportive care (BSC). The most common factor influencing the decision to abandon the palliative chemotherapy was uncontrolled bleeding (57.1%). The median overall survival (OS) of all patients was 58 days (range, 2–342 days). The OS was significantly shorter in BSC than in the chemotherapy group (median, 16 vs 99 days, P < 0.001). In multivariate analysis, chemotherapy was independently associated with longer OS. In the chemotherapy group, the response to treatment was evaluable in 11 patients: two (18.2%) had a partial response, five (45.5%) had stable disease and four (36.4%) had progressive disease. The OS of patients with progressive disease was significantly longer in the chemotherapy group than in the BSC group (median, 92 vs 16 days, P = 0.009). Conclusions: The prognosis is poor with gastric cancer that initially presents with DIC but palliative chemotherapy, compared with BSC, prolongs OS. Therefore, early and intensive management for correctable DIC followed by chemotherapy should be considered in this population.  相似文献   
1000.
Do person characteristics determine when novel, attention-grabbing stimuli loose their novelty? The aim of the present study was to investigate habituation of the visual event-related potentials (ERP) P3a and P3b in men that (1) were engaged in extreme sports, (2) had extremely high scores on the Impulsivity Sensation Seeking scale of the Zuckerman–Kuhlman Personality Questionnaire (ZKPQ), yet were not engaged in extreme sports, or (3) had extremely low scores on ZKPQ. The results showed that P3a habituated significantly more in extreme sporters than in the other groups. The same was not found in comparison of the high and the low ZKPQ scorers. There were not differences between the groups in overall amplitude. It is concluded that ERP habituation may be more relevant than mere amplitude to the sensation seeking trait in extreme sporters, and that they differ from others in ERPs related to automatic alerting-related processes, not controlled cognitive processing.  相似文献   
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