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221.
The present, study was conducted to determine the level of malondialdehyde (MDA) as an index of free radial induced lipid peroxidation and antioxidant vitamins-vitamins A, vitamin C and vitamin E in 75 confirmed cases of urolithiasis. Significantly high level of MDA (p<0.001) with significantly low levels of vitamin E (p<0.001) and vitamin A (p<0.001) with no significant decrease in vitamin C (p>0.05) were observed in the plasma of urolithiasis cases as compared to normal controls. In conclusion, it appears that a role of lipid peroxidation and oxidative function exists in the pathogenesis of urolithiasis. But, the exact mechanism how this occurs remains to be elucidated.  相似文献   
222.
Necessary and sufficient conditions are obtained for the realization of an m-variable positive real function (PRF) as the impedence function of a resistively-terminated ladder network of m lossless two-ports connected in cascade. Each two-port is a single-variable lossless ladder with all of its transmission zeros either at the origin or at finity. Conditions are also obtained when each of the two-ports is a Fujisawa-type lowpass ladder.  相似文献   
223.
Circadian rhythm of serum glucose, pyruvate, lactate and lactate dehydrogenase (LDH) was studied in normal healthy young volunteers at the onset (I Group, 7 cases) and peak (II Group, 8 cases) of winters in India with highly varied temperature. There was a significant difference, in the circadian rhythm of glucose, pyruvate and lactate dehydrogenase (LDH) of the two groups. A clockwise shift was observed in acrophase except in serum lactate, which is related to the energy demand in association with time qualified changes in diurnal activity of the individuals and change in photoperiod.  相似文献   
224.
This paper discusses a multivariable array whose elements are multivariable homogeneous polynomials which may have missing terms in any of the variables. This array permits one to obtain conditions for the realizability of a driving-point function or a transfer function as a resistively terminated low-pass ladder network. By reac- tance transformations, other forms of ladder structures can be obtained. The case of cascade-separable ladder networks is discussed in detail.  相似文献   
225.
    
Gebhardt's[1] probabilistic model of relevance is examined and found not to represent adequately some characteristics of the relevance judgement process. An alternative model is proposed, which identifies two different types of “error” or probabilistic variation between relevance judgements. The two types arise from, first, the definition of the boundaries of the relevance classes, and secondly the actual assessment of an individual document on the underlying scale (which is assumed to be a continuum). The problems of quantifying the model, and of assessing its implications for retrieval testing, are discussed.  相似文献   
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227.
The objectives of the present study were to ascertain the variations in the serum levels of malondialdehyde and total antioxidant status, in head and neck malignancies with different stages, with and without oral antioxidant supplementation, before and after radiotherapy, and to validate the protective effects of an antioxidant supplementation during radiotherapy. The pretreatment values of serum malondialdehyde were significantly raised, while that of serum total antioxidant status were significantly declined in all the stages of head and neck malignancies, when compared with the healthy controls values (P<0.001). A significant correlation was observed related to the studied parameters and different stages of the disease. The study suggests that an oral antioxidant supplementation during radiotherapy is an effective mode in reducing oxidative stress. Antioxidant supplementation during radiotherapy may serve as an adjuvant therapy in malignancies offering a protection to normal cells that may further reduce the risk of developing secondary cancers.  相似文献   
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229.
    
This article describes the development of a systematic and practical methodology for assessing program effectiveness and monitoring student development in undergraduate decision sciences programs. The model we present is based on a student's progression through learning stages associated with four key competencies: technical, analytical, communicative, and managerial. Key learning activities are embedded in major courses, resulting in clear and documented demonstrated abilities from the student. The work is based upon what is formally known about student outcomes assessment and input from our own Management Information Systems (MIS) program stakeholders and accrediting bodies. The results of the assurance of learning model can be, in turn, used to refine curriculum and to meet accreditation standards.  相似文献   
230.
Concept acquisition in the human infant.   总被引:1,自引:0,他引:1  
The ability of 18-, 24-, and 30-week-old infants to learn conceptual categories regarding adult female faces was examined using a habituation paradigm. Little evidence for conceptual categorization occurred at 18 or 24 weeks, but at 30 weeks infants learned to respond to "a specific female face regardless of orientation" and to "female faces in general."  相似文献   
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