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1.
ＭＥＡＳＵＲＥＭＥＮＴＯＦＳＯＤＡＣＴＩＶＩＴＹＢＹ~（１９）ＦＮＵＣＬＥＡＲＭＡＧＮＥＴＩＣＲＥＳＯＮＡＮＣＥ（ＮＭＲ）ＲＥＬＡＸＡＴＩＯＮＲＡＴＥＺｈａｏＢａｏ－Ｌｕ；ＣｈｅｎＹｕｎ－ＺｕｎａｎｄＸｉｎＷｅｎ－Ｊｕａｎ（ＩｎｓｔｉｔｕｔｅｏｆＢｉ?.. 相似文献
2.
R. B. Bhogade A. N. Suryakar N. G. Joshi R. Y. Patil 《Indian journal of clinical biochemistry : IJCB》2008,23(3):233-237
Hemodialysis represents a chronic stress status for its recipients. Many hypotheses state that this may be associated with
oxidative stress. Thus, there may be deficiency of antioxidants like erythrocytic superoxide dismutase, catalase, vitamin
E or increased generation of free radicals like superoxide anions. A study was carried out to investigate oxidant and antioxidant
status in chronic renal failure patients undergoing hemodialysis and effect of vitamin E supplementation on these two status.
Blood samples were collected from patients before and after hemodialysis and from controls. The samples were analyzed for
quantitation of MDA as index of lipid peroxide, nitric oxide, vitamin E, vitamin C and enzymatic antioxidants namely erythrocyte
SOD and catalase. As compared to controls, the levels of serum MDA were significantly increased and activities of erythrocyte
SOD and catalase, levels of serum nitric oxide, serum vitamin E and plasma vitamin C were significantly decreased both before
and after hemodialysis. The efficiency of vitamin E therapy in hemodialysis patients was assessed by re-evaluating oxidant
and antioxidant status of same patients after supplementation of vitamin E. Vitamin E supplementation caused decrease in serum
MDA and increase in levels of serum nitric oxide, vitamin E, vitamin C and activities of erythrocytic SOD and catalase. Our
results suggest the presence of oxidative stress and the possible preventive role of vitamin E therapy in hemodialysis patients. 相似文献
3.
烟雾吸入伤早期氧化与抗氧化动态平衡变化的实验研究 总被引：1，自引：0，他引：1
采用大鼠烟雾吸入伤模型，动态观察了伤后血浆、支气管肺泡灌洗液（ＢＡＬＦ）和肺组织中超氧化物歧化酶（ＳＯＤ）活性、丙二醛（ＭＤＡ）和共轭二烯（ＣＤ）含量的变化，辅以动脉血气分析、肺水量测定、ＢＡＬＦ中白细胞分类计数和病理检查．结果发现，伤后动物出现急性呼吸衰竭和严重肺水肿，肺内大量炎细胞聚集浸润；血浆、ＢＡＬＦ及肺组织中ＳＯＤ活性明显降低，ＣＤ和ＭＤＡ含量显著增加，ＭＤＡ／ＳＯＤ比值亦明显增高，且与ＢＡＬＦ中中性粒细胞数增加显著相关，提示氧化与抗氧化平衡失调可能在急性烟雾吸入性肺损伤的发生发展中起重要作用 相似文献
4.
Indranil Chakraborty Sanjoy Kunti Mousumi Bandyopadhyay Anindya Dasgupta Gopal Deb Chattopadhyay Sandip Chakraborty 《Indian journal of clinical biochemistry : IJCB》2007,22(2):109-113
An imbalance in the systemic redox status leading to oxidative stress has been an important factor in development of senile
cataracts, which is reflected by an increase in serum TBARS and a decrease in plasma SOD activity. Zinc has been an important
cofactor required for structural stability of SOD. In the present study the role of serum zinc level and plasma SOD activity
was analyzed in senile cataract patients showing significant oxidative stress. Serum TBARS, plasma SOD and serum zinc level
was measured in thirty randomly selected senile cataract patients against properly matched controls. Although, the analysis
of means showed a significant increase in serum TBARS and decrease in plasma SOD and serum zinc level in cases, but plasma
SOD was found to be just significantly correlated (p=0.05) with the serum zinc only in the cases. The results of partial correlation
studies and multiple regression analysis, also, showed only a significant correlation and predictable dependence between serum
TBARS and plasma SOD, excluding any role of serum zinc level. The present study concludes that it is chiefly the plasma SOD
activity, but not the serum zinc level, that determines the proneness of the patients for development of senile cataract. 相似文献
5.
Vidya Akhileshwar Samir P. Patel Surendra S. Katyare 《Indian journal of clinical biochemistry : IJCB》2007,22(1):84-90
Studies were carried out to examine and compare the effects of alloxan-diabetes on reactive oxygen species (ROS) related parameters
in the heart from male and female rats. Effects of insulin treatment were also evaluated. The diabetic state severely compromised
the ROS defense mechanism in the cardiac tissue and the effects were more pronounced in the female than in the male rats.
There was several fold increase in the xanthine oxidase (XO) activity in general and the magnitude of increase was higher
in the females; insulin treatment resulted in further increase in the XO activity. The glucose-6-phosphate dehydrogenase (G6PDH)
and catalase activities decreased and the reduced glutathione (GSH) content in mitochondria was completely depleted in diabetic
state with significant decrease in the GSH levels in the post-mitochondrial fraction; the effect was more pronounced in the
females. The superoxide dismutase (SOD) and glutathione peroxidase (GPox) activities increased in the diabetic state to a
greater extent in male rats. Insulin treatment had restorative action only on some parameters. In conclusion, our results
suggest that diabetic state may further compromise the weak ROS defense systems in the heart thus initiating a lesion at the
level of mitochondria which ultimately leads to cardiomyopathy and the effects are especially more pronounced in the females.
Our results also pointed out that insulin treatment was ineffective in restoring ROS related parameters. 相似文献
6.
《国际创新研究学报(英文)》2023,7(2):127-141
This study aims to show how activity theory in the socio-technical systems paradigm can assist in understanding and managing system innovation. We conceptualize socio-technical systems to address societal needs as activity systems and system innovations as transformations of such systems. Transformations result from resolving contradictions that develop due to technical and social change within and between the activities carried out by various agencies to fulfill societal needs. Along this line, the explanation of system innovations focuses on identifying emerging contradictions, resolution initiatives, and their outcomes, whereas the governance of system innovations can be carried out by interactively developing policies through successive interventions to resolve contradictions. We demonstrate the employment of activity theory to understand the transformation of the recorded music socio-technical system towards streaming, as well as to facilitate the management of the transition of the olive oil-producing sector at the regional level towards a circular economy through the adoption of innovative waste-processing technology. 相似文献
7.
S. Biswas A. Bhelwa A. Ittoop S. Biswal N. Nath 《Indian journal of clinical biochemistry : IJCB》1994,9(2):75-78
Normal polymorpho nuclear leucocytes (PMNL) when assaulted with diabetic serum factorin-vitro, recorded enhanced generation of oxygen free radical, and lysosomal degranulation. It also caused a decrease in the cytosolic
superoxide dismutase activity. Time-plot studies revealed PMNL susceptibility to diabetic serum factor for oxidative injury
and concomitant decrease in SOD, consequential for lysosomal degranulation. 相似文献
8.
Syed Ali Ajwad Tomas Ménard Emmanuel Moulay Michael Defoort Patrick Coirault 《Journal of The Franklin Institute》2019,356(16):10031-10057
This paper deals with the leader-following consensus problem of multi-agent systems with the consideration that each agent can only transmit its position state to the neighbors at irregular discrete sampling times. In the proposed algorithm, a continuous-discrete time observer is designed for the continuous estimation of both position and velocity from the discrete position information of the neighbors. These estimated states are then used for designing a continuous control law which solves the leader-following consensus problem. Moreover, the dynamics of the leader is not fixed and can be controlled through an external input. The stability analysis has been carried out by employing the Lyapunov approach which provides sufficient conditions to tune the parameters according to the maximum allowable sampling period. The developed algorithm has been simulated and then tested on an actual multi-robot system consisting of three differential drive wheeled robots. Both simulation and hardware results validate the effectiveness of the control algorithm. 相似文献
9.
Reactive oxygen species (ROS) are believed to be responsible for pathogenesis of various diseases affecting tissues and systems.
ROS generated by mitochondrial electron transport chain as well as extra-mitochondrially are eliminated by the respective
defense mechanisms. We checked the activity of ROS generating system such as xanthine oxidase and also the parameter of ROS
defense mechanism e.g. superoxide dismutase (SOD), catalase, glutathione peroxidase (GPox), reduced glutathione content (GSH)
and glucose-6-phosphate dehydrogenase (G6PDH) in mitochondrial and post-mitochondrial fractions from various tissues (liver,
kidney, brain and heart) of normal rats. Extent of lipid peroxidation (LPO) which is immediate consequence of ROS generation
was also examined. Our results shows that significant tissue-specific differences exist in mitochondrial and cytosolic ROS
generating systems and ROS defense mechanisms. 相似文献
10.
纳米氧化锌对人肺腺癌细胞A549的毒性 总被引：3，自引：0，他引：3
探讨纳米氧化锌（ZnO）对体外培养的人肺腺癌细胞A549的生物学效应。使用原子力显微镜（AFM）、透射电镜（TEM）和X射线衍射仪（XRD）研究纳米ZnO颗粒物的理化性质。然后,使用0mmol/L、0.1mmol/L、0.5mmol/L、1mmol/L、5mmol/L、10mmol/L的纳米ZnO处理体外培养的人肺腺癌A549细胞,MTT 法测定细胞生长活性。并且测定1mmol/L 纳米ZnO染毒24h后细胞培养液上清中,乳酸脱氢酶（LDH）和胞内的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）的活性以及丙二醛（MDA）的含量。使用透射电镜和流式细胞仪检测细胞凋亡的情况。荧光染色检测细胞产生活性氧（ROS）的生成。实验所用的ZnO纳米颗粒为长75 nm、直径20nm的针状纤锌矿晶体。细胞实验结果表明,纳米ZnO颗粒对A549细胞的生长活性具有明显的抑制作用,存在剂量－效应关系。培养液上清中LDH活性显著升高（P < 0.05）,胞内CAT活性显著下降、MDA含量显著升高（P < 0.01）,但SOD活性下降不明显。荧光染色检测发现染毒后A549细胞出现细胞凋亡,而且细胞内ROS的生成与纳米ZnO存在剂量－效应关系。结论是纳米氧化锌诱导人肺腺癌A549细胞产生活性氧,引发细胞凋亡,并产生细胞毒性。 相似文献
11.
Jagannath G. Satav Surendra S. Katyare 《Indian journal of clinical biochemistry : IJCB》2004,19(2):23-31
The reports in the literature on effects of diabetes on mitochondrial energy-linked functions are conflicting. Hence we carried
out systematic studies to evaluate the effects at the early and the late stages of the disease using STZ-diabetic rat as a
model. At the end of one week, after induction of diabetes, respiration rates with glutamate and succinate as the substrates
increased; respiration rates with other substrates e.g. β-hydroxybutyrate, pyruvate + malate and ascorbate + TMPD were not
affected despite substantial decrease in the β-hydroxybutyrate dehydrogenase activity and cytochrome b and c+c1 contents. Insulin treatment brought about increase in the cytochrome contents beyond control values. The ATPase activity
was generally low in the diabetic animals and was not restored by insulin treatment.
At the end of one month, the respiratory activities with all the substrates were generally low. Insulin treatment either restored
or stimulated the respiration rates beyond control values. The content of cytochromes was differentially affected in the diabetic
animals, but insulin treatment caused significant increase beyond control levels. The pattern for ATPase activity was similar
to the early effects.
At both the stages i.e. early and late stages of diabetes the mitochondria were tightly coupled. The ADP/O ratios were in
normal expected ranges and the respiratory control ratios were comparable with the control groups. Insulin treatment resulted
in apparent restoration of respiratory activity. However, the effects on the cytochromes and dehydrogenases activities were
differential. Taken together the two observations would suggest that the mitochondria were not re-instated to normality despite
apparent restoration of respiratory function. 相似文献
12.
A procedure for approximating fractional-order systems by means of integer-order state-space models is presented. It is based on the rational approximation of fractional-order operators suggested by Oustaloup. First, a matrix differential equation is obtained from the original fractional-order representation. Then, this equation is realized in a state-space form that has a sparse block-companion structure. The dimension of the resulting integer-order model can be reduced using an efficient algorithm for rational L2 approximation. Two numerical examples are worked out to show the performance of the suggested technique. 相似文献
13.
Core and infrastructure business activities are vital to the organization, and are growing more and more dependent on information systems. Theory suggests that more core and infrastructure business activities would inspire more strategic information systems planning which in turn would result in greater planning effectiveness. One hundred thirty chief information officers in manufacturing companies completed a questionnaire about the extent that their organization performed core and infrastructure business activities, and carried out technical, personnel, and procedures planning. The findings showed that infrastructure activities lead to all three types of planning whereas core activities lead only to procedures planning. Moreover, they showed that technical planning leads to planning effectiveness whereas personnel and procedures planning do not. The findings suggest that future researchers might try to uncover the reasons that core activities do not lead to more information systems planning. For practitioners, the findings suggest that managers reconsider how their organizations respond to core and infrastructure needs, and whether they should adjust their information systems planning. 相似文献
14.
BackgroundDefense-related anti-oxidative response is a vital defense mechanism of plants against pathogen invasion. Ralstonia solanacearum is an important phytopathogen. Bacterial wilt caused by R. solanacearum is the most destructive disease and causes severe losses in patchouli, an important aromatic and medicinal plant in Southeast Asia. The present study evaluated the defense response of patchouli inoculated with virulent R. solanacearum.ResultsResults showed that the basic enzymatic activities differed not only between the leaves and stems but also between the upper and lower parts of the same organ of patchouli. POD, SOD, PPO, and PAL enzymatic activities were significantly elevated in leaves and stems from patchouli inoculated with R. solanacearum compared to those in control. The variation magnitude and rate of POD, PPO, and PAL activities were more obvious than those of SOD in patchouli inoculated with R. solanacearum. PAGE isoenzymatic analysis showed that there were one new POD band and two new SOD bands elicited, and at least two isoformic POD bands and two SOD bands were observably intensified compared to the corresponding control.ConclusionOur results suggest that not only defense-related enzymatic activities were elevated but also the new isoenzymatic isoforms were induced in patchouli inoculated with R. solanacearum. 相似文献
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《Journal of The Franklin Institute》2022,359(9):4331-4345
This paper is concerned with the stability of sampled-data systems with constant delay. Firstly, by dividing the interval of sampling periods in two subintervals, two separate looped functionals are employed in each of these subintervals. Then, a new Lyapunov functional that combines classical Lyapunov functionals and looped-functionals is constructed. Furthermore, several zero equalities which consider the intrinsic relationships of state vectors in the system are introduced into the derivative of the constructed functional, and some stability criteria with less conservatism are obtained in forms of linear matrix inequalities (LMIs). Finally, two numerical examples are carried out as to verify the effectiveness and advantages of our method. 相似文献
19.
利用SBR亚硝化处理化肥厂实际废水,研究其短程生物脱氮过程中pH、溶解氧、进水氨氮负荷和温度等因素影响,并确定亚硝化处理的最佳操作条件。结果表明,pH过低会抑制亚硝酸盐的生成,过高则不利于反硝化菌反硝化过程TN的去除;当pH值控制在8.0左右时,亚硝化率保持较高水平,同时出水TN浓度控制较好。当DO浓度为0.2~0.3 mg/L时,亚硝化反应继续进行,但NH4+-N亚硝化反应速率较慢;当DO浓度为1.5~2.8 mg/l时,无法实现系统中亚硝化的运行,硝化作用成为主要反应。高氨氮负荷进水有利于亚硝酸盐的积累,但对出水氨氮去除效果不佳。较高的温度有利于亚硝化反应进行。当t=35℃,初始pH控制在7.8~8.2,DO控制在0.5~0.6mg/L,进水浓度NH4+-N为100mg/L时,SBR亚硝化操作过程为最佳,此时亚硝化率基本稳定在90%以上。 相似文献
20.
Alternating-current (AC) electrokinetics involve the movement and behaviors of particles or cells. Many applications, including dielectrophoretic manipulations, are dependent upon charge interactions between the cell or particle and the surrounding medium. Medium concentrations are traditionally treated as spatially uniform in both theoretical models and experiments. Human red blood cells (RBCs) are observed to crenate, or shrink due to changing osmotic pressure, over 10 min experiments in non-uniform AC electric fields. Cell crenation magnitude is examined as functions of frequency from 250 kHz to 1 MHz and potential from 10 Vpp to 17.5 Vpp over a 100 μm perpendicular electrode gap. Experimental results show higher peak to peak potential and lower frequency lead to greater cell volume crenation up to a maximum volume loss of 20%. A series of experiments are conducted to elucidate the physical mechanisms behind the red blood cell crenation. Non-uniform and uniform electrode systems as well as high and low ion concentration experiments are compared and illustrate that AC electroporation, system temperature, rapid temperature changes, medium pH, electrode reactions, and convection do not account for the crenation behaviors observed. AC electroosmotic was found to be negligible at these conditions and AC electrothermal fluid flows were found to reduce RBC crenation behaviors. These cell deformations were attributed to medium hypertonicity induced by ion concentration gradients in the spatially nonuniform AC electric fields. 相似文献