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991.
Sunil Chandy M. N. Sadananda Adiga Girija Ramaswamy C. Ramachandra Lakshmi Krishnamoorthy 《Indian journal of clinical biochemistry : IJCB》2008,23(3):258-261
Folate and cobalamin (Vitamin B12) are two essential micronutrients involved in one-carbon metabolism, which affects heart disease, neural tube defects and
cancer. Methylenetetrahydrofolate reductase, the key enzyme involved in one carbon metabolism produces methyl tetrahydrofolate
from methylene tetrahydrofolate, which in turn donates methyl group to homocysteine to generate methionine. There exist two
common low function polymorphic variants of the methylenetetrahydrofolate reductase gene involving nucleotides 677 C→T and
1298 A→C, which are associated with hyperhomocysteinemia. These polymorphisms are also linked with increased risk for certain
cancers such as breast cancer and at the same time providing a protective effect on colorectal cancer. In this case control
study, we have evaluated levels of folic acid, vitamin B12 and homocysteine in patients with colorectal cancer. Folate and homocysteine levels did not differ significantly between
the two groups; however an increasing trend was noticed with increase in homocysteine levels. Vitamin B12 levels were increased in cases compared to control group. 相似文献
992.
A. Ravi Raja G. N. Vishal Babu Geraldine Menezes T. Venkatesh 《Indian journal of clinical biochemistry : IJCB》2008,23(2):200-203
Awareness about the toxic effects of non-essential metals is still lacking in developing countries. Lead is one among them,
which ranks second in the Agency for Toxic Substances and Disease Registry’ s top 20 lists of toxic metals. Some of the herbal
medicines prepared from certain roots and leaves are known to contain this toxic metal at alarming levels. We have a case
of a person who suffered from the toxic effects of lead such as vomiting and colicky abdominal pain after consuming a herbal
remedy for Jaundice treatment. This went unrecognized initially because of the presence of multiple problems like Malaria
and Renal calculi. Lead poisoning as causative factor for anemia, vomiting and colic were confirmed only when blood lead concentration
was estimated. A combination of chelation therapy and nutritional supplementation was found to be useful in reducing the body
lead burden. 相似文献
993.
K. Devika Rani N. Suneetha Shruti Mohanty Pragna Rao 《Indian journal of clinical biochemistry : IJCB》2008,23(2):150-153
This study is conducted in chronic alcoholics to assess the association of an Individual’s level of serum homocysteine with
the success of achieving alcohol deaddiction in the patient. The patients’ nutrition status is also assessed. 50 chronic alcoholics
admitted to a deaddiction center were inducted into the study. Patients underwent an 8 weeks holistic program to promote rehabilitation
from alcoholism. All the patients were addicted to alcohol for 8 – 10 years. Of the 50 patients enrolled, 39 of them completed
the 8 weeks program including complete abstinence from alcohol during this period. Fasting blood samples were collected on
admission and again after 8 weeks of alcohol abstinence for analyses of serum homocysteine and serum prealbumin, transferrin,
total proteins and albumin, gammaglutamyl transferase (GGT) and alanine transaminase (ALT). Of the 50 patients enrolled in
the study, 39 completed the 8 weeks rehabilitation program. 11 patients discontinued within 2 weeks of admission. During the
8 weeks of complete alcohol abstinence, patients were given a balanced diet and multivitamin supplements. A significant improvement
in their nutritional status was noted by the elevation of serum levels of prealbumin, transferrin, total proteins and albumin.
Serum homocysteine levels decreased significantly (p<0.002) to normal levels from previous hyperhomocytenemia. This was accompanied
by decrease in serum GGT and ALT levels indicating improved liver functions. Serum estimation of homocysteine in chronic alcoholics
is important to assess whether the patient will have a successful rehabilitation. Normal homocysteine levels are achieved
after dietary changes and abstinence from alcohol. Timely correction of hyperhomocysteinemia also provides successful rehabilitation. 相似文献
994.
995.
The paradoxical profession: Teaching at the turn of the century 总被引:1,自引:0,他引:1
996.
997.
This study tested the Adult Distance Study Through Computer Conferencing (ADSCC) model developed by Eastmond (1994), to determine if learner readiness, online features, and CMC‐related learning approaches are associated with learner satisfaction in an academic computer conference. All three variables were correlated with learner satisfaction and online features emerged as the best predictor of learner satisfaction. Results indicate interrelationships between the three variables. The ADSCC model was a good predictor of learner satisfaction. It provided a useful framework for understanding learner satisfaction by showing how to categorise the different components that influence satisfaction in an academic computer conference. 相似文献
998.
This article summarizes the case for adopting a cross-cultural comparative approach to the study of educational administration and leadership. In the first section, we state the main arguments for strengthening a societal cultural approach to educational administration and leadership. The second and third sections outline why culture is a useful concept for analysis and comparison in educational administration, and briefly review the concept of culture itself. The fourth section outlines an influential approach for investigating the influence of culture, that of Hofstede, and suggests that his framework provides a worthwhile starting point for educational researchers. The final section notes a number of important issues which researchers need to consider when exploring the influence of societal culture on educational administration. In summary, we suggest that a cross-cultural comparative approach to educational administration and leadership can expose the value of theory and practice from different cultural perspectives which may then, in turn, inform and influence existing dominant paradigms. 相似文献
999.
1000.
In 1904, Prandtl proposed the concept of boundary layers that revolutionised the study of fluid mechanics. In this article we present the basic ideas of boundary layers and boundary-layer separation, a phenomenon that distinguishes streamlined from bluff bodies. 相似文献