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71.
Tendinopathy, an important sports injury afflicting athletes and general public, is associated with huge economic losses. The currently used diagnostic tests are subjective, show moderate sensitivity and specificity; while treatment failures persist despite advances in therapy. This highlights the need for tendinopathy diagnostic and treatment monitoring tools. This study investigates tendon injury, natural healing and effect of treatment using ATR‐FTIR complemented with histopathology. Control (C), injured (I) and treated (T) rat tendons were extracted 3, 7, 14 and 28 days post‐injury/treatment, representing phases of healing; and subjected to hematoxylin & eosin staining as well as spectroscopy. While C showed no change, I‐ and T‐related histological changes could be clearly observed in stained sections. ATR‐FTIR spectra highlighted the biochemical changes within groups. Multivariate analysis could classify C, I and T with 75%; different days between groups with 84%; and different days within group with 65% efficiency. Results suggest that such analysis can not only identify C, I or T but also different phases of healing. Difference between I and T at different time points also suggest change in rate of healing. Further studies may help develop this technique for clinical diagnosis and treatment monitoring in future.   相似文献   
72.
The application of the expanded granular sludge bed (EGSB) reactor for the anaerobic treatment of low-strength soluble wastewaters using ethanol as a model substrate was investigated in laboratory-scale reactors at 30oC. Chemical oxygen demand (COD) removal efficiency was above 80% at organic loading rates up to12 g COD/L . d with influent concentrations as low as 100 to 200 mg COD/L. These results demonstrate the suitability of the EGBS reactor for the anaerobic treatment of low-strength wastewaters. The high treatment performance can be attributed to the intense mixing regime obtained by high hydraulic and organic loads. Good mixing of the bulk liquid phase for the substrate-biomass contact and adequate expansion of the substrate-biomass contact and adequate expansion of the sludge bed for the degassing were obtained when the liquid upflow velocity (V(up)) was greater than 2.5 m/h. Under such conditions, an extremely low apparent K(s) value for acetoclastic methanogenesis of 9.8 mg COD/L was observed. The presence of dissolved oxygen in the wastewater had no detrimental effect on the treatment performance. Sludge piston flotation from pockets of biogas accumulating under the sludge bed occurred at V(up) lower than 2.5 m/h due to poor bed expansion. This problem is expected only in small diameter laboratory-scale reactors. A. more important restriction of the EGSB reactor was the sludge washout occurring at V(up) higher than 5.5 m/h and which was intensified at organic loads higher than 7 g COD/L. d due to buoyancy forces from the gas production. To achieve an equilibrium between the mixing intensity and the sludge hold-up, the operation should be limited to an organic loading rate of 7 g COD/L d. and to a liquid up-flow velocity between 2.5 and 5.5 m/h (c) 1994 John Wiley & Sons, Inc.  相似文献   
73.
74.
Electricity generation from microbial fuel cells which treat food processing wastewater was investigated in this study. Anaerobic anode and aerobic cathode chambers were separated by a proton exchange membrane in a two-compartment MFC reactor. Buffer solutions and food industry wastewater were used as electrolytes in the anode and cathode chambers, respectively. The produced voltage and current intensity were measured using a digital multimeter. Effluents from the anode compartment were tested for COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity. The maximum current density and power production were measured 527 mA/m2 and 230 mW/m2 in the anode area, respectively, at operation organic loading (OLR) of 0.364 g COD/l.d. At OLR of 0.182 g COD/l.d, maximum voltage and columbic efficiency production were recorded 0.475 V and 21%, respectively. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity were 86, 79, 73, 18, 68, 62, 30 and 58%, respectively. The results indicated that catalysts and mediator-less microbial fuel cells (CAML-MFC) can be considered as a better choice for simple and complete energy conversion from the wastewater of such industries and also this could be considered as a new method to offset wastewater treatment plant operating costs.  相似文献   
75.
摘要 目的:探讨急诊危重孕产妇5分钟紧急剖宫产的临床效果,并分析新生儿不良结局的危险因素。方法:回顾性分析2018年1月~2022年6月在河北省儿童医院妇产科收治的急诊危重孕产妇139例的临床资料。根据急诊剖宫产流程分为对照组(n=68,常规紧急剖宫产流程下进行手术)及观察组(n=71,5分钟紧急剖宫产)。观察两组孕产妇的手术情况、手术反应时间、孕产妇并发症、新生儿不良结局发生率。采用多因素Logistic回归模型分析新生儿不良结局的危险因素。结果:两组住院时间、术中出血量、术中输血情况组间对比,未见统计学差异(P>0.05)。与对照组相比,观察组进手术室至手术开始时间、决定手术至胎儿娩出的时间间隔(DDI)、决定手术至进手术室时间、手术开始至胎儿娩出时间均更短,新生儿不良结局发生率、并发症发生率更低(P<0.05)。根据新生儿不良结局将孕产妇分为不良组(n=38)、良好组(n=101)。单因素分析结果显示:新生儿不良结局与受教育程度、新生儿体重、孕周、剖宫产类型、DDI、妊娠合并症、采用辅助生殖技术有关(P<0.05)。多因素Logistic回归分析结果显示,受教育程度为小学及其以下、新生儿体重偏低、剖宫产类型为I类剖宫产、孕周偏短、DDI偏长均是新生儿不良结局的危险因素(P<0.05)。结论:急诊危重孕产妇5分钟紧急剖宫产可缩短各项手术反应时间,降低孕产妇并发症和新生儿不良结局发生率。此外,新生儿不良结局的发生与受教育程度、新生儿体重、剖宫产类型、孕周、DDI等因素有关。  相似文献   
76.
The effect of microbial enzymes in reducing the disposable solid content of sludge was investigated. A mixture of industrial cellulase, protease, and lipase, in equal proportion by weight, reduced total suspended solids (TSS) by 30–50% and improved settling of solids. An increase in solid reduction was observed with increasing enzyme concentration. The effect of combinations of enzyme treatments indicated that two-enzyme combinations of protease and cellulase produced better solid reduction than individual enzymes and that lipase further augmented this effect. Among the individual enzymes, protease produced a more settleable sludge as compared to cellulase and lipase. Adjustment of the pH of the enzymatically treated sludge to the acidic range (pH 2–4) further improved solid reduction, and adjustment to the alkaline range (pH 10–12) improved settleability. Journal of Industrial Microbiology & Biotechnology (2001) 26, 383–386. Received 01 November 2000/ Accepted in revised form 29 April 2001  相似文献   
77.
建立了利用显微操作技术分离植物单个染色体的方法。以黑麦(Secale cereale L.)为材料,以其标准染色体组型图为依据,识别出黑麦含抗病基因的1R染色体。经显微操作,将单条1R染色体放入Ep-pendorf管中。研究表明,用α-溴奈饱和液对细胞进行预处理,可快速鉴别出黑麦1R染色体。采用去壁低渗制片技术,可明显地改善显微分离单染色体的条件。  相似文献   
78.
An endogenous soluble protease has been demonstrated to unmask a Ca2+-stimulated ATPase activity in purified dog gastric microsomes. The presence of ATP during protease treatment appears essential for the manifestation of the gastric Ca2+-stimulated ATPase activity. The endogenous protease appears to have trypsin-like activity, since soybean trypsin inhibitor completely blocks the protease effect. Manifestation of the Ca2+-stimulated ATPase occurs without affecting the microsomal (H+ +K+)-ATPase activity and associated H+ uptake ability. The unmasked Ca2+-stimulated ATPase appears insensitive to calmodulin. Possible roles of the enzyme in the regulation of gastric H+ transport have been discussed.  相似文献   
79.
80.
Nine species of marine algae have been assessed for the presence of novel hemagglutinins not extractable with buffer, unless the algal tissue was pretreated with Pronase. All species examined contained hemagglutinins, indicating the existence of a novel group of hemagglutinins which differed from those reported previously in marine algae.  相似文献   
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