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51.
Carbohydrate deficient transferrin (CDT) is one of the conventional markers for chronic alcohol consumption, is used by researchers
and clinicians. A number of enzymes are affected by ethanol intake. The induction or inhibition of sialyl transferase and
plasma sialidase may be involved in the CDT level elevation. An alteration of protein transport during post-translational
modification could be a primary mechanism in the impairment of protein metabolism associated with chronic alcohol abuse. Transferrin
being a steroid responsive protein, sex-based hormonal variations might contribute to the lower sensitivity of CDT. Varying
hormonal statuses such as pregnancy, use of contraceptives, menopause/ menstrual cycle can alter iron homeostasis in women.
CDT levels are markedly affected by iron homeostasis. Several CDT assay methods appeared promising, but it is not readily
apparent which technique is the most accurate. Moreover, false-positive results of CDT have been reported in non-alcohol related
hepatic failure and in rare conditions. Therefore clinical interpretation of CDT needs careful assessment in patients with
alcohol-related or non-alcohol-related health disorders. 相似文献
52.
Parsunpriya Nayak Subir Kumar Das D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2006,21(2):53-57
Aluminum and alcohol, both are well-accepted neurotoxin. The plausible mechanisms for their neurotoxicity are also common.
Therefore, the effect of ethanol on aluminum induced biochemical changes in rat brain is being studied. In the present study,
ethanol exposure significantly affected the aluminum and protein content of brain. The activities of acid phosphatase and
alkaline phosphatase were also changed. Aluminum exposure, on the other hand, contributed significantly in the alterations
of aluminum content, acid phosphatase acivity and aspartate aminotransferase activity. Though ethanol co-exposure significantly
influenced the aluminum load of brain, the interactions of these two neurotoxins were found to be significant only in case
of acid phosphatase activity of brain. Therefore, it can be suggested that general neurotoxicity produced by aluminum is not
modified by ethanol. However, the aluminum load caused by aluminum exposure, may be influenced by ethanol co-exposure. 相似文献
53.
54.
Subir Kumar Das Hiran K. R. Sukhes Mukherjee D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2007,22(1):99-104
Damaging effects of reactive oxygen species on living systems are well documented. They include oxidative attack on vital
cell constituents. Chronic ethanol administration is able to induce an oxidative stress in the central nervous system. In
the present study, 16–18 week-old male albino rats of Wistar strain were exposed to different concentration of ethanol for
4 weeks. This exposure showed profound effect on body weight. Ascorbic acid level; and activities of alkaline phosphatase
and aspartate transaminase in the brain are dependent on the concentration of ethanol exposure. Chronic ethanol ingestion
elicits statistically significant increase in thiobarbituric acid reactive substances level and decrease in gluatathione level
in the brain. It reduces superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase activities in a
dose dependent manner. However, histological examination could not reveal any pathophysiological changes. Therefore, we conclude
that biochemical alterations and oxidative stress related parameters respond early in alcoholism than the histopathological
changes in brain. 相似文献
55.
Santosh C. Das Aminu Z. Mohammed Sani U. Al-Hassan Abraham A. Otokwula Uche P. Isichei 《Indian journal of clinical biochemistry : IJCB》2007,22(2):79-83
In order to see the pattern of changes in differential serum lipid and lipoprotein fractions as a risk marker of coronary
complication in paired ‘maternal—neonate’ blood samples in an iodine deficient zone, 26 pregnant women and their corresponding
new born infants at term delivery from the iodine deficient Bassa region of Plateau state, Nigeria were assessed and the results
were compared with those seen in a similar 44 group of women and their newborns assessed in non lodine deficient region of
Jos. The serum thyroid function and lipid and lipoprotein profiles were determined by ‘ELISA’ and ‘enzymatic’ methods respectively.
Urinary iodide excretion level was also measured in 14 pregnant women in Bassa, 23 pregnant women in Jos and 16 non pregnant
control from Jos. Results indicate that the pregnant women assessed in Bassa were iodine deficient (P<0.01) and their thyroid
status was strikingly reduced as reflected by a drop in serum level of T4/TBG ratio (P<0.01) and a rise in TSH (P<0.005) in
comparison to that seen in Jos. There was marked hypertriglyceridaemia and total hypercholesterolaemia (P<0.005), with differential
significant rise in LDL cholestotol fraction (P<0.005) in the women assessed in Bassa as compared to Jos. The HDL cholesterol
however dropped less significantly in the group (P<0.05) with a concurrent marked rise (P<0.001) in the serum ratio of LDL
cholesterol/HDL cholesterol, total cholesterol/HDL cholesterol and triglycerides/HDL cholesterol in the lodine deficient group.
A similar pattern of changes were seen in the corresponding neonates in the Bassa group as compared to Jos group. It is concluded
that the pregnant women and their newborn offsprings living in a longstanding environmental iodine deficiency run a higher
risk of developing coronary complications than those living in non endemic region. It is striking that such newborns surrounded
by a continued state of lodine deficient may at a later adult-period of life develop marked risk of coronary complication
and other features of hyperlipidaemias associated with varying thyroid insufficiency and accompanied iodine deficiency disorders.
Prophylaxis measures as intervention has been highlighted. 相似文献
56.
Pathways to understanding mind: construct validity and predictive validity of maternal mind-mindedness 总被引:6,自引:0,他引:6
Meins E Fernyhough C Wainwright R Clark-Carter D Das Gupta M Fradley E Tuckey M 《Child development》2003,74(4):1194-1211
The construct validity of maternal mind-mindedness (MM) was investigated in the context of its relations with children's later understanding of mind. MM measures were obtained from infant-mother (N = 52) interactions at 6 months, and from maternal interviews at 48 months. Children's understanding of mind was assessed using theory of mind (ToM) tasks at 45 and 48 months, and a stream of consciousness (SoC) task at 55 months. One of the early MM measures--mothers' appropriate mind-related comments--was a positive independent predictor of: (a) MM at 48 months, and (b) ToM and SoC performance at 45 to 55 months. Path analyses suggested direct links between mothers' use of appropriate mind-related comments and children's later understanding of mind. 相似文献
57.
The purpose of this study was to examine the contribution of PASS (Planning, Attention, Simultaneous, and Successive) processes to Chinese reading accuracy and fluency. One-hundred-forty Grade 3 to 5 Mandarin-speaking children were assessed on measures of PASS processes, phonological awareness, and orthographic knowledge. A year later they were assessed on reading accuracy and fluency. The results indicated that successive processing predicted reading through the effects of phonological awareness and simultaneous processing predicted reading through the effects of orthographic knowledge. The results were similar for reading accuracy and fluency. Implications for the PASS theory are discussed. 相似文献
58.
In this paper we address the issue of separating reading disability from general intelligence in order to identify those cognitive processes which discriminate between poor and good readers when intelligence is covaried. Subjects were 140 Grade 5 and 6 students who were administered Lorge-Thorndike intelligence test (1964), a reading decoding test and cognitive tests which measure planning, attention-arousal and simultaneous-successive processing. The tests which emerged as discriminators between good and poor readers when Lorge-Thorndike full scale IQ was covaried, were three measures of successive processing (Sequence Repetition, Naming Time, Speech Rate) and a measure of selective attention, the familiar Stroop Color-Word test. Subsequently, a comparison of reading disabled high and low average IQ children confirmed that the four tests were performed poorly by both groups. All four tests involve the use of articulatory representation, confirming the important role speech-related processes play in reading (decoding). The results support the notion that deficient speech-related processes may be the central problem of the majority of poor readers, especially those of above-average intelligence. Future directions for research on phonological coding and articulation were suggested. 相似文献
59.
This experiment focused on differences that occur with age and reading skill in the use of phonemic codes in short-term retention tasks where stimuli were presented visually. In 1 condition, individuals recalled 6-letter strings composed of rhyming and nonrhyming letters after a 15-sec delay under conditions that permitted phonemic coding and rehearsal. 2 other conditions were designed to suppress (a) rehearsal of certain types of phonemic codes in the delay interval and (b) both phonemic coding at stimulus presentation and rehearsal. Subjects were grade 2 average readers matched in reading skill with grade 4 disabled readers, grade 4 average matched with grade 6 disabled, and grade 6 average matched with grade 4 superior readers. Average readers showed a decrease in errors with age in all 3 conditions, although performance was always better in the nonsuppression condition. In the latter, memory for nonrhyming letters was always better than memory for rhyming letters. Differential use of phonemic codes by good and poor readers in grades 4 and 6 was less than that found in previous research with younger children. Finally, by comparing the performances of grade 2 average with grade 4 disabled readers and grade 4 average with grade 6 disabled readers, the developmental lag hypothesis of reading disability was examined. Problems with testing the hypothesis are discussed. 相似文献
60.
Roy Rajib Das Niladri 《International Journal for Educational and Vocational Guidance》2020,20(1):49-77
International Journal for Educational and Vocational Guidance - This study assesses the influence of gender differences in the formation of entrepreneurial intention. Specifically, we investigate... 相似文献