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11.
Summary Self-diffusion coefficients of zinc and iron were determined in acid soil of Palampur and alluvial soil of Ludhiana under varying pH, CaCO3, moisture, carrier and phosphorus levels. Increase in pH caused tremendous reductions in self-diffusion coefficients (Da) of both zinc and iron in soil. The selfdiffusion coefficients of both these elements were drastically reduced as a result of CaCO3 application. The Da values of zinc and iron increased with the decrease in moisture tension and increase in carrier and phosphorus levels. The decrease in Da values were associated with increase in capacity factor.  相似文献   
12.
Aging is a naturally biological process with adverse effects. The continuous accumulation of reactive oxygen species (ROS) trigger cellular and tissue damage by activating several aging enzymes. The antioxidant properties of traditional medicinal plants used by Jakun aborigine’s community are a promising approach to alleviate aging process and prevent Alzheimer. The aim of the current investigation was to optimize a novel anti-aging formulation from traditional plants (Cnestis palala stem, Urceola micrantha stem, Marantodes pumilum stem and Microporus xanthopus fruiting bodies) using simplex centroid mixture design (SCMD). After selecting the optimal formulations based on desirability function of antioxidant activity (DPPḢ, ABTṠ+ and FRAP), they were further examined against the activity of aging-related-enzymes (collagenase, tyrosinase, acetyl- and butyrylcholinesterase). The single extracts of C. palala, U. micrantha and the binary mixture of C. palala and U. micrantha were the optimal formulations with high antioxidant activities. Single extract of U. micrantha showed the highest inhibition towards matrix metalloproteinase-1 (49.44 ± 4.11 %), while C. palala water extract showed highest inhibitions towards tyrosinase (14.06 ± 0.31%), acetylcholinesterase (32.92 ± 2.13%) and butyrylcholinesterase (34.89 ± 2.84%) enzymes. The single extracts of C. palala and U. micrantha displayed better activity as compared to the binary mixture formulation. In conclusion, these findings could be a baseline for further exploration of novel anti-aging agents from natural resources.  相似文献   
13.
Theories of short term memory often include a limited capacity "buffer". Such a buffer contains items which do not decay at all but are overwritten by new data. I show that one of the experiments that fueled the buffer concept, the free recall experiments by Murdock (J Exp Psychol 64(5):482-488, 1962), does not contain such a buffer.  相似文献   
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15.
目的:比较髁突-翼外肌解剖复位与游离复位治疗髁状突骨折的疗效,促进髁突形态恢复。方法:收治的80例单侧髁状突骨折患者随机分为两组,每组40例,A组行髁突-翼外肌解剖复位术,B组行髁状突游离复位术,术后3个月、6个月观察髁突形态及下颌骨运动功能变化。结果:A组治愈率为90%,高于B组的70.00%(P0.05);术后3个月A组髁状突吸收、张口受限、开口偏斜、咬合关系紊乱、关节弹响发生率分别为12.50%、15.00%、15.00%、7.50%、12.50%,均低于B组的32.50%、35.00%、37.50%、25.00%、35.00%(P0.05);术后6个月A组张口受限、关节弹响发生率为5.00%、2.50%,均低于B组的20.00%、20.00%(P0.05);两组术后并发症发生率比较差异无统计学意义(P0.05)。结论:髁突-翼外肌解剖复位术保留髁状突骨折患者骨折断端血运,髁突形态及下颌骨运动能力恢复良好,疗效优于髁状突游离复位术。  相似文献   
16.
We studied enzymatic adipyl-7-ADCA hydrolysis as a new process for the production of 7-aminodeacetoxycephalosporanic acid (7-ADCA), one of the building blocks for cephalosporin antibiotics like cephalexin and cefadroxil. Adipyl-7-ADCA hydrolysis carried out with immobilised glutaryl acylase was considerably enhanced by addition of phenylglycine amide, the side-chain donor used for cephalexin synthesis; unlike reactions carried out with free enzyme. The rate enhancing effect was not specifically related to phenylglycine amide; we found a linear relationship between the reaction rate and the buffering capacity of the added substance. These observations can be explained by a pH-gradient in the immobilised enzyme, the pH inside the particle being lower (corresponding to low enzyme activity) than outside. It was concluded that the buffer reduced the pH-gradient inside the biocatalyst, and therewith, caused the reaction rate enhancing effects. Further, chloride ions decreased the reaction rate strongly, while sodium, magnesium, sulphate, and potassium did not influence the reaction rate much. For an actual process, it is important to use a buffer that is appropriate for the reaction-pH. In that way the amount of enzyme required in a process can be reduced considerably, in our case a factor of three was found.  相似文献   
17.
在 5± 1℃条件下对中缅树鼠句进行冷驯化处理 ,测定其能量代谢。冷驯化 2 8d后 ,体重比对照组显著增加 7 3 3 % ;整体能值达到 3 0 47± 0 46kJ/g (N =8) ,比对照组增加4 98% ;摄入能比对照组增加 3 6 1 7% ;同化能比对照组增加 6 6 2 % ;生长能达到 6 98±0 5 3kJ/1 0 0g (N =7)体重·天 ,是对照组的 4 85倍 ;维持能比对照组增加 6 4 0 % ,达到3 5 2 96± 2 8 3 4kJ/1 0 0g体重·天 (N =7)。以上结果表明中缅树鼠句在冷胁迫影响下 ,以增加能量摄入、能量储存和维持能和降低排泄能量的生理机制来维持能量代谢平衡 ,以此对策来提高低温环境适应能力  相似文献   
18.
Cognitive impairments affect the majority of patients with schizophrenia and these impairments predict poor long term psychosocial outcomes.  Treatment studies aimed at cognitive impairment in patients with schizophrenia not only require demonstration of improvements on cognitive tests, but also evidence that any cognitive changes lead to clinically meaningful improvements.  Measures of “functional capacity” index the extent to which individuals have the potential to perform skills required for real world functioning.  Current data do not support the recommendation of any single instrument for measurement of functional capacity.  The Virtual Reality Functional Capacity Assessment Tool (VRFCAT) is a novel, interactive gaming based measure of functional capacity that uses a realistic simulated environment to recreate routine activities of daily living. Studies are currently underway to evaluate and establish the VRFCAT’s sensitivity, reliability, validity, and practicality. This new measure of functional capacity is practical, relevant, easy to use, and has several features that improve validity and sensitivity of measurement of function in clinical trials of patients with CNS disorders.  相似文献   
19.
棉花根际解磷菌的解磷能力和分泌有机酸的初步测定   总被引:9,自引:1,他引:9  
利用特殊培养基对盐碱地棉花根际解磷菌进行了分离以及pH值和分泌有机酸能力的初步测定。利用溶磷圈法筛选出10个解磷能力较高的菌株进行深入研究,其中液体培养条件下测定了菌株的溶磷能力,有效磷在4.04~185.63 mg/L,其中wpL2溶磷量达到185.63 mg/L;测定了培养液pH值,下降到5.12~6.67,但是pH与溶磷量之间没有线性关系,测定了培养液的有机酸含量,菌株溶磷量与有机酸总量没有线性相关性,其中所分离到的解无机磷菌株均可以分泌酒石酸,除此之外,wpc1还分泌乙酸,wpc2和wpL2还分泌柠檬酸;分离到的解有机磷菌株均可分泌乙酸,除此之外,ypL1和ypc2分泌酒石酸,ypL3分泌柠檬酸,ypL2和ypc3分泌柠檬酸和丁二酸,均不能产生苹果酸。  相似文献   
20.
基于VIC模型模拟的干旱区土壤水分及其时空变化特征   总被引:3,自引:0,他引:3  
土壤水分在陆地水循环中起着十分重要的作用,大尺度、长时间及高精度的土壤水分监测是旱情预警、生态恢复与精准农业决策部署的重要指导依据,而陆面过程模式模拟在时空尺度上可获得更准确的土壤水分特征。以渭-库绿洲为目标靶区,结合VIC陆面过程模型和土地利用类型变化,探讨2009—2016年研究区年际间不同地类土壤水分时空变化规律,并用实测数据进行精度验证,结果表明:(1)东北区域土壤含水率模拟值较高,土壤含水量低值集中在研究区西部与南部区域。(2)盐渍土壤表层含水量高于耕地,每年雨季,灌丛土壤含水量高于其他3种地类,由于大量荒地转为耕地,绿洲荒地土壤含水量与耕地土壤相互接近,在28.784—53.741 mm之间。(3)渭-库绿洲近7年耕地与盐渍地面积大幅度增加,耕地与盐渍地面积增幅达35%以上,荒地面积相较2009年减少约46%,灌丛面积增幅约15%。(4)荒地土壤含水量伴随面积大幅度下降,土壤含水量数值集中在正态曲线28.6 mm以上区域。VIC模拟值与实测值均方根误差(RMSE)范围在1.4—2.80之间,RE范围在0.90—2.20之间,R2范围在0.40—0.60...  相似文献   
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