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971.
K. S. S. Saibaba P. V. L. N. Srinivasa Rao K. V. Dakshina Murty M. Vijaya Bhaskar 《Indian journal of clinical biochemistry : IJCB》1997,12(2):139-141
Selecting the correct method for routine analysis by ‘method evaluation’ is an important component of quality assurance. It
is a step-wise procedure that evaluates various analytical parameters like accuracy, precision etc of the given method. Finally
reference intervals are established for selected population. We evaluated an enzymatic method for serum creatinine. The results
show that it is an acceptable method based on the above mentioned criteria. 相似文献
972.
Tree-structured vector quantization (VQ) is a technique designed to represent a codebook that simplifies encoding as well as vector quantizer design. Most design algorithms for tree-structured VQ used in the past are based on heuristics that successively partition the input space. Recently, Chou, Lookabaugh and Gray proposed a tree-pruning heuristic in which a given initial tree is pruned backwards according to certain optimization criterion. We define the notion of an optimal pruned tree subject to a cost constraint and study the computational complexity of finding such an optimal tree for various cost functions. Under the assumption that all trees are equally probable, we show that, on the average, the number of pruned trees in a given tree is exponential in the number of leaves. Furthermore, we prove that finding an optimal pruned tree subject to constraints such as entropy or the expected-depth is NP-hard. However, we show that when the constraint is the number of leaves, the problem can be solved in polynomial time. We develop an algorithm to find the optimal pruned tree in O(nk) time, where n is the size of the initial tree and kis the constraint size. 相似文献
973.
974.
Since accurate decisions are required for effective management, much research has focused on information systems that support decision making. Recently, this research has engendered frameworks, such as the management support system (MSS), that are designed to provide comprehensive and integrated support for the decision making process. Few, if any, studies have empirically measured the effects of these frameworks on decision making. This article offers empirical evidence on MSS effectiveness. It overviews the decision making process, presents an MSS for supporting the process, and assesses the influences of the MSS on the process and outcomes of health care decision making. The paper also examines the implications of the analyses for information systems research and health care practice. 相似文献
975.
K. A. Faseehuddin Shakir Basavaraj Madhusudhan 《Indian journal of clinical biochemistry : IJCB》2007,22(1):117-121
Rats fed with hypercholesterolemic diet showed a significant increase in serum total—cholesterol, liver homogenate total-cholesterol,
HDL-cholesterol and changed LDL-cholesterol, and HDL/LDL ratio in comparison to control. Flaxseedchutney (FC) supplemented diet (15%, w/w) was found to be more effective in restoring lipid profile changes in rats fed with cholesterol,
(1.0%). The activities of serum marker enzymes glutamate oxaloacetate transminase (GOT), glutamate pyruvate transaminase (GPT)
and alkaline phosphatase (ALP) were elevated significantly in carbon tetrachloride induced rats. Administration of flaxseedchutney (15%, w/w) resulted in depletion of serum marker enzymes and exhibited recoupment thus showing significant hepatoprotective
effect. It was observed that flaxseedchutney supplemented diet could lower the serum cholesterol and as a potential source of antioxidants it could exert protection against
hepatotoxic damage induced by carbon tetrachloride (CCl4) in rats. 相似文献
976.
Ramesh Chander Farhan Rizvi A. K Khanna Ram Pratap 《Indian journal of clinical biochemistry : IJCB》2003,18(2):71-79
Guggulsterone, a mixture of cis (E) and trans (Z) isomers (7∶3 w/w) was synthesized from 16-DPA. The isomers were separated
by column chromatography and evaluated for cardioprotective and antioxidant activities. Myocardial necrosis induced by isoproterenol
in rats caused marked increase in serum creatine phosphokinase and glutamate pyruvate transaminase. Simultaneously in ischemic
heart, phospholipase, xanthine oxidase and lipid peroxides were enhanced following depletion of glycogen, phospholipids and
cholesterol. Treatment with guggulsterone and its both isomers at the dose of 50 mg/kg po., significantly protected cardiac
damage as assessed by the reversal of blood and heart biochemical parameters in ischemic rats. The cardioprotective activity
of guggulsterone and of both the isomers were compared with that of gemfibrozil at the same doses. Guggulsterone and both
the isomers at tested concentrations (5–20mM) inhibited oxidative degradation of lipids in human low-density lipoprotein and
rat liver microsomes induced by metal ionsin vitro. The drug counteracted against the generation of superoxide anions (O2) and hydroxyl radicals (OH−) in non-enzymic test systems. It is suggested that cardioprotective and antioxidant activities of synthetic guggulsterone
and guggulsterone obtained from gum resinCommiphora mukul that contains isomers E & Z in the ratio of 46∶54w/w are the same. 相似文献
977.
J. Baxi Kavita Sharma Rajbala Asha Mehta A. K. Pendse P. P. Singh 《Indian journal of clinical biochemistry : IJCB》1994,9(1):47-49
Evaluation of serum SOD and MDA level was done in 21 first episode renal stone formers, 9 recurrent stone formers, 20 patients with obstructive uropathy other than urolithiasis and 12 patients with urinary infection. Twenty-two healthy volunteers were taken as controls. The level of SOD in respective groups was 2.12±0.84, 2.78±0.85, 1.42±0.31, 1.98±0.70 and 2.32±0.62 units/ml and of MDA was 2.61±1.07, 2.69±1.15, 1.65±0.33, 1.33±0.34 and 1.55±0.48 n mol/ml respectively. The results indicate increased peroxidative stressin nephrolithiasis only. Since SOD level was normal in all groups, this increased peroxidative stress in nephrolithiasis should be due to factors other than this one. 相似文献
978.
K. Pratibha T. Seenappa K. Ranganath 《Indian journal of clinical biochemistry : IJCB》2007,22(2):158-161
Alkaptonuria, a metabolic disorder characterized by a triad of homogentisic aciduria, arthritis and ochronosis is one of the
first conditions in the charter of group of inborn errors of metabolism proposed to have Mendelian recessive inheritance.
It is due to the deficiency of the enzyme homogentisic acid oxidase which catalyzes the conversion of homogentisic acid to
maleylacetoacetic acid in the catabolism of tyrosine. Homogentisic acid thus accumulates in cells and body fluids and its
oxidized polymers bind to collagen, leading to progressive deposition of grey to bluish black pigment resulting in degenerative
changes in cartilage, intervertebral disc and other connective tissues, leading to arthritis which is the only disabling effect
in an affected older individual. However the diagnosis can be made in neonates when blackish stain is noticed in an unwashed
diaper. Alkaptonuria is treated symptomatically, surgical intervention necessitates in advanced stages, treatment with ascorbic
acid (Vitamin C) and dietary restrictions of food containing phenylalanine and tyrosine have proved to be successful in alleviating
the symptoms. 相似文献
979.
Y.A. Saet 《Journal of The Franklin Institute》2005,342(5):489-501
A system of non-Hermite, non-orthogonal functions that are new for concrete applications is introduced to generate explicit and previously unknown, physically meaningful solutions for bar and plate equations. The approach allows in some cases to establish completeness of these sets of solutions. Various other separate results technically related to these basic development are presented. In the available literature there are no registered efforts to extract the two velocities from exact solutions of the equations of the processes in which the two parameters are explicitly present. 相似文献
980.
K. Pratibha Usha Anand Rajni Agarwal 《Indian journal of clinical biochemistry : IJCB》2004,19(2):128-131
Serum adenosine deaminase (ADA), 5′ nucleotidase (5′NT) and malondialdehyde (MDA) were estimated in patients with acute infective
hepatitis (AIH) along with the routine parameters of liver disease. Present study is done to evaluate these special parameters
in patients with clinical history of AIH and to assess the utility of these parameters as diagnostic/ prognostic indices of
liver function and to correlate special parameters with routine live function tests (LFT). ADA, 5′NT and MDA along with routine
LFT was estimated in 25 patients with AIH and 25 samples from healthy voluntary blood donars served as the control group.
Routine LFT was estimated by standard clinical chemistry procedures on dade behring analyser and ADA, 5′NT and MDA were estimated
by berthlot reaction, fiske and subbarao method and thiobarbituric acid method respectively.
Statistical analysis showed that serum ADA, 5′NT and MDA were significantly higher in patients as compared with the controls.
There was a significant positive correlation between ADA and total bilirubin and MDA and total bilirubin. Hence we can conclude
that these tests would be more sensitive to diagnose the patients with AIH and that the raised bilirubin levels could be looked
upon, as a protective mechanism which the liver has evolved in order to combat oxidative stress. 相似文献