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71.
目的:研究血清IL-18与亚代谢综合症(亚MS)、代谢综合症(MS)的关系,探讨生活方式改变(TLC)后IL-18及相关标记物的变化及其临床意义。方法:16例对照组,14例亚MS组,34例MS组;采用自动生化仪测定空腹血脂水平;采用乳胶增强免疫比浊法检测hs-CRP水平;采用ELISA法检测受试者血清IL-18、IL-6和脂联素水平。结果:MS患者血清IL-18水平与腰围有明显相关性(rs=0.45,P<0.01);与亚MS组比较,MS组IL-18水平显著升高(P<0.01);与正常组比较,MS组患者的腰围、体重指数、hs-CRP、IL-6及IL-18显著升高(P<0.05)。TLC后体重减轻5%,MS患者IL-18、IL-6、hs-CRP水平显著降低(P<0.01),脂联素水平显著升高(P<0.01)。结论:IL-18可作为亚MS和MS预测指标,鉴别亚MS与MS,其含量的变化对病情进展的程度及疗效的判定有重要意义。  相似文献   
72.
目的探讨Kruppel样因子4(Kruppel-like factor 4,KLF4)在内毒素血症小鼠中的表达模式及意义。方法运用实时荧光PCR技术和Western blot技术,分别从mRNA水平和蛋白水平探讨内毒素血症小鼠肝脏和肺脏中KLF4的表达;运用生物信息学技术,对启动子区含有KLF4的结合位点的炎症介质基因进行了预测;运用RT-PCR技术,从mRNA水平探讨内毒素血症小鼠肝脏和肺脏中IL1β的表达模式。结果内毒素血症小鼠肝脏和肺脏中KLF4 mRNA的表达下凋,KLF4蛋白的表达先下凋后升高;IL-18、IL-15、IL-12、IL-18、IL-10等炎症介质基因的启动子区均含有KLF4的结合元件,这些炎症基因的表达可能直接受到KLF4的调控;内毒素血症小鼠肝脏和肺脏中IL-IB的表达模式与KLF4的表达模式呈相反趋势。结论内毒素血症小鼠肝脏和肺脏中KLF4表达下调,KLF4在炎症介质基因表达调控中可能具有重要作用。  相似文献   
73.
Previous work showed that goldfish learn to avoid a region of an aquarium where they receive a discrete shock to the flank. This avoidance is reduced if another fish is present next to the shock zone, suggesting fish trade-off avoidance against a tendency to associate [Dunlop, R., Millsopp, S., Laming, P., 2006. Avoidance learning in goldfish (Carassius auratus) and trout (Oncorhynchus mykiss) and implications for pain perception. App. Anim. Behav. Sci. 97 (2–4), 255–271]. Only shock intensity was adjusted in those experiments, here we report results where a requirement for food was also altered.Fish were trained to feed at a region of the aquarium where subsequently they would receive a discrete shock to the flank. One experimental group had different shock intensities applied, whereas in the other group shock intensity was consistent but food deprivation was varied.We show the number of feeding attempts and time spent in the feeding/shock zone decreased with increased shock intensity and with increased food deprivation the number and the duration of feeding attempts increased as did escape responses as this zone was entered. These data suggest that goldfish balance their need for food against avoidance of an acute noxious stimulus.  相似文献   
74.
采用NADPH-d组织化学方法,观察电针对大鼠一侧足底注射5%福尔马林50μl后病灶所属脊髓节段(L4-L6)一氧化氮合酶(NOS)阳性反应的影响。结果表明,福尔马林组大鼠L4-L6节段脊髓胶状质NOS阳性反应较生理盐水组显著增强,电针治疗组大鼠L4-L6节段脊髓胶状质NOS阳性反应与生理盐水组无显著差异。但明显弱于福尔马林组,提示电针治疗能抑制大鼠足底疼痛病灶所属脊髓节段NO合成,减弱脊髓神经元的敏感化,从而发挥镇痛作用。  相似文献   
75.
Oxidoreductases are a group of enzymes that have been regarded uneconomical for industrial processes due to their dependence on cofactors or prosthetic groups for activity and the difficulties of regenerating these. Especially, flavoproteins have long been neglected for biocatalytical applications. The prosthetic group of some of these enzymes, but not all, can be regenerated by oxygen, resulting in hydrogen peroxide formation, which is detrimental to enzyme stability. As a contribution to alleviating this problem, a novel concept for the regeneration of electron acceptors (redox mediators) for flavoenzymes is described. Flavin-containing enzymes such as cellobiose dehydrogenase (CDH) or pyranose oxidase (P2O) are used in conjunction with laccases and a redox mediator. The flavin of the synthetic enzyme is reduced while the oxidized product of interest is formed, in turn, the flavin is reoxidized with the help of an electron acceptor, which then is regenerated using a laccase. Laccases are copper containing phenol oxidases that can transfer four electrons to oxygen, producing two molecules of water. Preliminary screening experiments with different redox mediators, and a coupled enzyme system of CDH and laccase, showed that a wide variety of different substances can efficiently shuttle electrons between these two enzymes. Among them are substituted and unsubstituted ortho- and para-quinones, benzoquinone imines, cation radicals such as 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), redox dyes such as phenothiazines or phenoxazines, as well as iron complexes.

Experiments in which CDH completely oxidizes lactose to lactobionic acid and P2O entirely converts glucose to 2-keto-glucose are presented. Catalytic amounts of redox mediators are used and continuously regenerated by a laccase. Specific productivities of up to 19.3 g·(h·kU)−1 and 72 g·(h·kU)−1 for CDH and P2O, respectively, were found. The total turnover numbers (TTNs) for the two enzymes used were in the range of 105–106. Oxygen supply for the laccase is a crucial factor in avoiding rate limitation. Undeniably, this system facilitates the efficient use of a hitherto underexploited group of enzymes for preparative purposes.  相似文献   

76.
In the past 20 years, inorganic fuel cells have been transformed from novelty devices to practical energy transfer-energy storage units. However, the advantage of the high operating efficiency afforded by these fuel cells is partially offset by (a) the limited viability and high cost of the catalysts, (b) the highly corrosive electrolytes, and (c) the elevated operating temperatures. The possibility exists to reduce some of these problems through the development of bioelectrochemical fuel cells. Such biological/electrochemical systems incorporate either microorganisms or enzymes as an active component within the specified electrode compartments. Recent studies with microorganisms as part of the anode compartment have been aimed at defining the mechanism of the observed electrochemical reactions. Recent investigations on the use of cell-free enzyme preparations in the electrode compartments have dealt primarily with developing methodology and defining mechanisms for enhancing the rate of electron transfer from the enzyme-cofactor active site to the solid electrode surface. Applications of this developing technology have been envisioned for analytical chemistry, medical devices, energy transfer, electrochemical synthesis, and detoxification. In this review, the theory and problems of bioelectrochemical fuel cells are described and related to research, both recent and proposed, for the practical development of this area.  相似文献   
77.
Rotator cuff stress during upper limb weight-bearing lifts presumably contribute to rotator cuff disease, which is the most common cause of shoulder pain in individuals with tetraplegia. Elbow extension strength appears to be a key determinant of rotator cuff stress during upper limb weight-bearing lifts since individuals with paraplegia who generate greater elbow extensor moments experience lower rotator cuff stress relative to individuals with tetraplegia. Biceps-to-triceps transfer surgery can increase elbow extension strength in individuals with tetraplegia. The purpose of this study was to determine whether active elbow extension via biceps transfer decreases rotator cuff stress during weight-bearing lifts in individuals with tetraplegia. A forward dynamics computational framework was used to estimate muscle stress during the lift; stress was computed as muscle force divided by the peak isometric muscle force. We hypothesized that rotator cuff stresses would be lower in simulated lifting with biceps transfer relative to simulated lifting without biceps transfer. We found that limited elbow extension strength in individuals with tetraplegia, regardless of whether elbow strength is enabled via biceps transfer or is residual after spinal cord injury, results in muscle stresses exceeding 85% of the peak isometric muscle stress in the supraspinatus, infraspinatus, and teres minor. The rotator cuff stresses we estimated suggest that performance of weight-bearing activities should be minimized or assisted in order to reduce the risk for shoulder pain. Our results also indicate that biceps transfer is unlikely to decrease rotator cuff stress during weight-bearing lifts in individuals with tetraplegia.  相似文献   
78.
本文在中医学理论的基础上,用现代科学来认识疼痛的的产生与疼痛的治疗机理,剖析穴位作为感受器与经络的内在联系,应用现代电子技术设计一种新颖的镇痛仪器。  相似文献   
79.
《Phytomedicine》2014,21(3):356-362
Trans-caryophyllene is a sesquiterpene present in many medicinal plants’ essential oils, such as Ocimum gratissimum and Cannabis sativa. In this study, we evaluated the antinociceptive activity of trans-caryophyllene in murine models of acute and chronic pain and the involvement of trans-caryophyllene in the opioid and endocannabinoid systems. Acute pain was determined using the hot plate test (thermal nociception) and the formalin test (inflammatory pain). The chronic constriction injury (CCI) of the sciatic nerve induced hypernociception was measured by the hot plate and von Frey tests. To elucidate the mechanism of action, mice were pre-treated with naloxone or AM630 30 min before the trans-caryophyllene treatment. Afterwards, thermal nociception was evaluated. The levels of IL-1β were measured in CCI-mice by ELISA. Trans-caryophyllene administration significantly minimized the pain in both the acute and chronic pain models. The antinociceptive effect observed during the hot plate test was reversed by naloxone and AM630, indicating the participation of both the opioid and endocannabinoid system. Trans-caryophyllene treatment also decreased the IL-1β levels. These results demonstrate that trans-caryophyllene reduced both acute and chronic pain in mice, which may be mediated through the opioid and endocannabinoid systems.  相似文献   
80.
ABSTRACT

Recently, the enzymatic approach has attracted much interest in the decolorization/degradation of textile and other industrially important dyes from wastewater as an alternative strategy to conventional chemical, physical and biological treatments, which pose serious limitations. Enzymatic treatment is very useful due to the action of enzymes on pollutants even when they are present in very dilute solutions and recalcitrant to the action of various microbes participating in the degradation of dyes. The potential of the enzymes (peroxidases, manganese peroxidases, lignin peroxidases, laccases, microperoxidase-11, polyphenol oxidases, and azoreductases) has been exploited in the decolorization and degradation of dyes. Some of the recalcitrant dyes were not degraded/decolorized in the presence of such enzymes. The addition of certain redox mediators enhanced the range of substrates and efficiency of degradation of the recalcitrant compounds. Several redox mediators have been reported in the literature, but very few of them are frequently used (e.g., 1-hydroxybenzotriazole, veratryl alcohol, violuric acid, 2-methoxy-phenothiazone). Soluble enzymes cannot be exploited at the large scale due to limitations such as stability and reusability. Therefore, the use of immobilized enzymes has significant advantages over soluble enzymes. In the near future, technology based on the enzymatic treatment of dyes present in the industrial effluents/wastewater will play a vital role. Treatment of wastewater on a large scale will also be possible by using reactors containing immobilized enzymes.  相似文献   
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