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31.
目的:探讨微创肺表面活性物质(pulmonary surfactant,PS)对呼吸窘迫综合征新生儿氧合功能、肝肾功能及呼吸功能的影响。方法:选择2018年3月至2019年3月我院收治的66例新生呼吸窘迫综合征的患儿作为研究对象,并按照随机数字表法分为观察组(n=33)和对照组(n=33)。对照组患儿采取常规的治疗方式,观察组患儿则在对照组治疗基础上应用微创PS治疗。观察比较两组患儿的动脉血气指标、Ⅱ型肺泡细胞表面抗原(KL-6)、巨噬细胞移动抑制因子-1(MIF-1)、高迁移率族蛋白1(HMGB-1)、肝肾功能、氧合指数及呼吸机参数。结果:治疗后,两组的氧分压(PaO_2)、二氧化碳总量(TCO_2)、氧饱和度(SaO_2)均较治疗前显著增高;且观察组以上指标均高于对照组。两组的Ⅱ型肺泡细胞表面抗原(KL-6)、巨噬细胞移动抑制因子-1 (MIF-1)、高迁移率族蛋白1(HMGB-1)均较治疗前显著降低,且观察组的以上指标均低于对照组。两组的谷草转氨酶(AST)、谷丙转氨酶(ALT)、尿素氮(BUN)、肌酐(CRE)水平均较治疗前显著降低,且观察组的以上指标均明显低于对照组。观察两组的呼吸机参数和氧合指数,发现两组的吸入氧浓度(FiO_2)、吸气峰压(PIP)、呼吸末正压(PEEP)、氧合指数(PaO_2/FiO_2,OI)均较治疗前有所改善,且观察组的以上指标均要优于对照组(P0.05)。结论:应用微创PS治疗新生儿呼吸窘迫综合征的效果显著,能明显改善患儿的动脉血气指标、肝肾功能以及氧合功能,减轻炎症反应,并减少机械通气的参数。  相似文献   
32.
The age‐related impairment in muscle function results in a drastic decline in motor coordination and mobility in elderly individuals. Regular physical activity is the only efficient intervention to prevent and treat this age‐associated degeneration. However, the mechanisms that underlie the therapeutic effect of exercise in this context remain unclear. We assessed whether endurance exercise training in old age is sufficient to affect muscle and motor function. Moreover, as muscle peroxisome proliferator‐activated receptor γ coactivator 1α (PGC‐1α) is a key regulatory hub in endurance exercise adaptation with decreased expression in old muscle, we studied the involvement of PGC‐1α in the therapeutic effect of exercise in aging. Intriguingly, PGC‐1α muscle‐specific knockout and overexpression, respectively, precipitated and alleviated specific aspects of aging‐related deterioration of muscle function in old mice, while other muscle dysfunctions remained unchanged upon PGC‐1α modulation. Surprisingly, we discovered that muscle PGC‐1α was not only involved in improving muscle endurance and mitochondrial remodeling, but also phenocopied endurance exercise training in advanced age by contributing to maintaining balance and motor coordination in old animals. Our data therefore suggest that the benefits of exercise, even when performed at old age, extend beyond skeletal muscle and are at least in part mediated by PGC‐1α.  相似文献   
33.
目的:探讨运动和膳食因素对小鼠脑内葡萄糖转运蛋白Glut1和Glut4基因表达的影响。方法:ICR小鼠分组施以高脂膳食、限量摄食、运动、高脂膳食+运动等不同实验干预60d,RT-PCR法测定大脑Glut1、Glut4 mRNA水平。结果:与正常对照组比较,运动组和限食组小鼠脑组织Glut1和Glut4基因表达显著增高,高脂膳食组小鼠Glut4基因表达显著降低而Glut1表达水平无显著改变。结论:限食和运动增强脑内胰岛素反应型Glut4和非胰岛素反应型Glut1基因的表达,高脂膳食降低脑内胰岛素反应型Glut4基因的表达。  相似文献   
34.
目的:观察一次性力竭运动过程及恢复期大鼠纹状体细胞外液中多巴胺(DA)和5-羟色胺(5-HT)及其代谢物浓度的动态变化规律。方法:采用活体微透析结合毛细管电泳.激光诱导技术,连续观察清醒大鼠在一次性力竭运动过程及恢复期纹状体细胞外液中酪氨酸(Tyr)、5-HT、5-羟吲哚乙酸(5-HIAA)、色氨酸(Trp)和DA浓度的动态变化。结果:大鼠纹状体细胞外液中TW、5-HT、5-HIAA水平运动初期均未见显著变化(P〉0.05),运动后期、力竭及恢复期均显著高于安静水平(P〈0.05,P〈0.01);DA、Tyr水平在运动后期、力竭及恢复期显著高于安静水平(P〈0.05,P〈0.01);DA/5-HT运动初期显著升高(P〈0.05,P〈0.01),运动后期出现下降趋势,力竭前15min降至最低点。而恢复期略有回升,但运动后期、力竭及恢复期与安静状态相比均无显著差异。结论:力竭运动过程中大鼠纹状体细胞外液中DA和5-HT的动态变化具有阶段性特征,运动疲劳过程中状体内DA和5-HT两种神经递质的代谢水平均显著增强,而其中以5-HT的作用占优。  相似文献   
35.
During olive oil production, large quantities of olive mill wastewater (OMW) are produced. This wastewater material, containing a high level of phenolic compounds, poses a serious environmental problem in almost all Mediterranean countries. Candida tropicalis YMEC14 was used as an extremophile strain to design an aerobic biotreatment process to detoxify OMW and reduce its polluting organic load. The process was enhanced by directing yeast metabolism towards biodegradation pathways using hexadecane as co-metabolite and by immobilizing yeast cells in calcium alginate beads. Under immobilization conditions, C. tropicalis YMEC14 grown at 40 degrees C in OMW supplemented with hexadecane resulted in 69.7%, 69.2% and 55.3% reduction of chemical oxygen demand, monophenols and polyphenols, respectively, after a 24-h fermentation cycle.  相似文献   
36.
我国正步入老龄化社会,研究如何有效延缓衰老,维护老年人的认知功能已成为当今老年医学亟待解决的问题之一。近年来,生活方式影响老年人认知功能的作用倍受关注。因此,本文综述运动和饮食干预对老年人认知发展的影响,并重点探讨其表观遗传学机理研究进展,有助于今后合理、有效地对认知功能衰退进行干预与研究。未来相关的研究应进一步严格研究设计,拓宽多因素的综合,形成更有解释力的、统一的、完整的理论体系。  相似文献   
37.
Ocean temperatures are rising and fish are redistributing themselves poleward and into deeper waters to retain a favourable thermal environment (11 and 30). To investigate whether biogeographical shifts might occur through behavioural redistribution into optimal environments, we examined whether a common triplefin species (Forsterygion lapillum) would behaviourally select (i.e. track) a temperature that matches its physiological optimum under laboratory conditions. F. lapillum were acclimated to 15, 18 or 21 °C for at least 4 weeks, after which various rates of oxygen consumption (MO2) were measured using automated respirometry and their behavioural thermal preferenda assessed using an electronic shuttle choice tank. Aerobic metabolic scope (resolved as the difference between maximal and maintenance MO2) did not differ across all thermal treatments (i.e. specimens acclimated to 15, 18 or 21 °C) revealing that F. lapillum is a eurythermal species with a range of optimal physiological performance that closely matches the environmental conditions they are exposed to. A comparably wide range of behavioural preference would perhaps be expected but all three acclimation groups showed a surprisingly narrow behavioural preference range of 20–21 °C. The results therefore suggest that, irrespective of acclimation, eurythermal species may have a tendency to select optimal temperatures at the upper limit of their thermal distribution range. The results are discussed in the context of the ecology and the expected response of F. lapillum to future thermal change.  相似文献   
38.
A thermotolerant bacterium, identified as Bacillus licheniformis, completely utilized 0.1% (w/v) NH4NO3 at 30 and 50°C under aerobic condition. The addition of 0.5 mM Fe2+ to the NH4NO3 medium markedly promoted the utilization of NH4+ and NO3. At 50°C, of total nitrogen originally provided, 24% was taken up into the cells and 20% remained in the culture supernatant. Residual nitrogen (56%) was probably removed into the atmosphere. The cell extracts contained enzymes involved in denitrification. GC-MS demonstrated that NH4 15NO3 had been converted to 15N2O. These results indicate that the strain has denitrification ability under aerobic condition.  相似文献   
39.
This study aimed to investigate the possible changes in serum leptin concentration caused by acute exercise and the effects of zinc deficiency on these changes. Forty male rats were divided into control-control, control-elercise, zinc-deficient-control, and zinc-deficient-exercise groups (10 rats in each). Control-exercise and zinc-deficient-exercise groups performed exercisse at 6 m/min speed on a rodent treadmill for 60 min or until exhaustion. All rats were decapitated 48h after the exercise, and blood samples were collected to determine serum leptin and zinc levels. Serum leptin levels in the zinc-deficient-control group were lower than in the control-control group. The mean exercise time of control-exercise group was significantly longer than the zinc-deficient-exercise group. We conclude that serum leptin levels significantly decrease both 48 h after strenuous exercise and in the zinc-deficient rats, and there is a further decrease in leptin levels when rats fed on a zinc-deficient diet performed exercise.  相似文献   
40.
利用富集培养的方法从南昌市郊某养鱼塘采样分离出22株反硝化细菌,其中8株反硝化率较高,从中选择一株效果最好的作为研究对象,命名为HS-N62,对其生长特性进行了深入研究。结果表明:硝酸盐氮初始浓度为140mg/L,菌株HS-N62在12h内对硝酸盐氮的去除率可达96%,而且没有亚硝酸盐氮的积累。该菌最适生长温度范围为30°C-37°C,最适生长pH范围6.0-8.0,最适C/N比为10:1,并能利用多种碳源生长。运用正交试验探讨了该菌株最适的反硝化条件。反硝化菌株HS-N62还具有较好的除磷能力,12h除磷率达到67.7%(初始磷酸盐浓度57mg/L)。通过形态学特性和生理生化分析以及16S rRNA基因序列分析,菌株HS-N62与Pseudomonas sp.亲缘关系最为接近,相似性达99%,初步鉴定该菌为假单胞菌属(Pseudomonas sp.)。  相似文献   
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