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941.
942.
943.
944.
Madhusudhana Rao A Anand U Anand CV 《Indian journal of clinical biochemistry : IJCB》2011,26(1):28-31
Numerous lines of evidence implicate a role of myeloperoxidase (MPO) in the pathogenesis of cardiovascular disease (CVD).
It is a well accepted fact that patients with chronic kidney disease (CKD) are at an increased risk for CVD. MPO is a pro-oxidant
enzyme which could be involved in the increased susceptibility of these patients to CVD. Hence, the levels of plasma MPO was
determined in healthy controls as well as in patients with CKD [stratified with the level of their kidney failure as CKD stages
II–V (end stage renal disease)]. Plasma MPO was assayed by a spectrophotometric method. Serum urea and creatinine were estimated
on a clinical chemistry analyzer using standard laboratory procedures. The mean plasma MPO levels were significantly lower
with advancing stages of renal failure (P < 0.001). There was a positive correlation between MPO and GFR (r = +0.89, P < 0.001) and a negative correlation with urea (r = −0.85, P < 0.001) and creatinine (r = −0.82, P < 0.001). While an inverse association was observed between plasma MPO and urea in CKD patients, such an association was
not observed in control subjects (P = 0.43). In conclusion, the decline in plasma MPO levels may be due to the inhibitory effect of uraemic toxins on the enzyme. 相似文献
945.
By coupling the heat transfer equation with semi-global chemical reaction kinetic equations, a onedimensional, unsteady mathematical model is developed to describe the pyrolysis of single biomass pellet in the pyrolysis zone of downdraft gasifier. The simulation results in inert atmosphere and pyrolysis zone agree well with the published experimental results. The pyrolysis of biomass pellets in pyrolysis zone is investigated, and the results show that the estimated convective heat transfer coefficient and emissivity coefficient are suitable. The mean pyrolysis time is 15.22%, shorter than that in inert atmosphere, and the pellet pyrolysis process in pyrolysis zone belongs to fast pyrolysis. Among the pyrolysis products, tar yield is the most, gas the second, and char the least. During pyrolysis, the temperature change near the center is contrary to that near the surface. Pyrolysis gradually moves inwards layer by layer. With the increase of pyrolysis temperature and pellet diameter, the total pyrolysis time, tar yield, char yield and gas yield change in different ways. The height of pyrolysis zone is calculated to be 1.51—3.51 times of the characteristic pellet diameter. 相似文献
946.
Vinita Ailani R. C. Gupta Sunil Kumar Gupta Kapil Gupta 《Indian journal of clinical biochemistry : IJCB》2009,24(4):426-429
This study was conducted to find out the level of oxidative stress and effect of supplementation of vitamin C, D and Calcium
on levels of SOD, serum and urinary fluoride in children residing in endemic fluorosis area. For this the fluoride belt of
Jaipur district was selected. The parameters selected were Super oxide dismutase, serum fluoride and urinary fluoride. The
study was conducted on one hundred children, selected from four areas (25 from each area) consuming water containing 1.2,
2.4, 5.6 and 13.6 mg/l of fluoride. Drinking water fluoride, serum and urinary fluoride were measured by Ion selective electrode
method. Serum SOD by Xanthine oxidase method using kit of Ransod (kit cat. No. SD125). The post treatment values showed a
significant reduction in serum fluoride and SOD. Urinary fluoride levels increased significantly in post treatment stage.
The results revealed a normal SOD levels in all groups but an increasing trend was observed with increasing fluoride concentration.
Treatment with Calcium, Vitamin D and Vitamin C showed a significant reduction in serum fluoride and SOD and increase in urinary
fluoride. A high positive correlation between pretreatment and post treatment group was observed in serum fluoride, SOD and
urinary fluoride (P < 0.05). The study indicated an increasing oxidative stress in cases of fluorosis with increasing drinking
water fluoride concentration. Treatment with Calcium, Vitamin D and Vitamin C resulted a significant reduction in serum fluoride
and SOD and increase in urinary fluoride. 相似文献
947.
948.
Pai-Lin Lee Hui-Hsiang Chang Chih Kun Huang Wen-Chen Cheng Pi-Yu Lee Hui-Chen Chao 《Educational gerontology》2013,39(10):614-626
ABSTRACTObjective: Memory loss affects a large proportion of older adults. Research indicates a positive association between memory training and better memory performance as people age. However, studies on specific memory training using an experimental design are limited. This study explored whether memory training has improved memory performance in a group of older adults.Method: A convenience sample of 48 participants was recruited from two communities. Disregarding dropouts, this left 23 experimental (mean age = 65.4 ± 6.0, range = 56–80) and 19 control participants (mean age = 64.5 ± 4.9, range: 57–72). The intervention consisted of 60-min classes held on a weekly basis continuing for 8 weeks. The class session was held after a 1-h exercise class and before a 1-h session of cognitive games. The pre–post objective memory performances, including associative, list, text, place, grocery learning, and transfer-effect of daily event memory (ecology validity), were examined to determine whether the intervention was effective.Results: Intragroup: With Wilcoxon test, the findings showed that the intervention of both the list and place learning had significant differences for the experimental group, but not for the control group. Intergroup: The main effects were found for the associative and text learning. The mixed design ANOVA indicated that there is an interaction (time x group) on the dependent variable of the place learning test. Daily events memory: We found within group that the pre–post differences were significant for the experimental group but not for the control group.Conclusion: The study showed that memory training can help older adults to ameliorate memory loss problems and these findings deserve more attention. 相似文献
949.
The paper focuses on the convergence of Finnish research and education in archival science with information science in general
and in records management with information management in particular. Two issues influencing this development are: the convergence
of professionals previously worked in the archival and library sectors and in information management and services; and the
wide-spread, extensive growth in the use of digital technology to manage internal and external organizational information.
At the level of society the opportunities provided by digital technology to manage heritage information in memory organizations
like archives, libraries and museums, are tremendous and the role of documentary heritage at the global, European and national
levels is well recognized. These developments are changing the information and operating environments of memory organizations
and public and private enterprises. These changes, in turn, are generating new requirements in archival science and records
management education and research. This paper focuses on the implications of these changes for the planning, implementation
and further development of an information studies curriculum. This curriculum development is considered crucial in order to
respond to the new demands, and is also implicitly linked to the emerging Finnish information society.
This article is based on Huotari, M.-L. and Valtonen, M.R., “Integrating Records and Archives Management with Information
Studies in Finland”, in L. Ashcroft (ed.),Continuity, Culture, Competition—the Future of Library and Information Studies Education, Proceedings of the 4th British-Nordic Conference on Library and Information Studies 21–23 March 2001, Dublin, Ireland, pp.
249–254 (Dublin: MCB UP Limited, 2002). 相似文献
950.
Venkateshwari A Sri Manjari K Krishnaveni D Nallari P Vidyasagar A Jyothy A 《Indian journal of clinical biochemistry : IJCB》2011,26(2):136-139
Pancreatic fibrosis is a key pathological feature in the etiology of chronic pancreatitis that leads to obliteration of exocrine
and endocrine pancreatic tissues and its replacement by fibrous tissue resulting in clinical manifestations. Matrix metalloproteinase
9 is a member of the MMP family that is also known as gelatinase B, degrades type IV collagen of extracellular matrix and
basal membrane. The present study is aimed at evaluating the clinical significance of plasma concentration of MMP-9 in chronic
pancreatitis. The samples were obtained from 112 chronic pancreatitis patients and an equal number of age and sex matched
healthy controls. MMP-9 levels were quantitatively measured by ELISA assay. Statistical analysis was applied to test the significance
of results. The present study revealed a significant increase of plasma MMP 9 levels in chronic pancreatitis patients compared
to control subjects. Elevated levels were also observed in all the patient groups compared to control subjects with regard
to sex, age, addictions etc. MMP-9 degrades the type IV collagens in normal basement membrane, which in turn activates the
pancreatic stellate cells which promote the development of pancreatitic fibrosis. Thus, elevated plasma levels of MMP-9 may
act as a susceptibility factor for the development of chronic pancreatitis. 相似文献