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41.
Everybody is familiar with the ubiquitous term ‘species’. But what is a species? Undeniably, this is one of the most complex dilemmas in the history of biology. There is no other concept in biology as elementary yet controversial as the concept of species. In practice, a species is regarded as the fundamental unit of comparison in all biological disciplines like systematics, evolution, ecology, ethology, physiology, and genetics. However, little agreement exists in the scientific community regarding the nature of species, whether it is a real entity or a cultural artifact, its biological significance or how to delineate a species. This article is a review of the seemingly endless debate on the species concept and its implications. 相似文献
42.
Chitra Upadhyaya Sandhya Mishra P. P. Singh Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2005,20(1):30-34
Serum antioxidant status and peroxidative stress was estimated in 30 pregnant women, their newborn infants and 25 non-pregnant
women. Serum Ascorbic acid, α-tocopherol, retinol & β-carotene levels were found to be significantly reduced and peroxidative
stress was significantly higher in mothers as compared to matched non-pregnant women. Newborn had significantly higher levels
of ascorbic acid as compared to their mother but had significantly lower levels of lipid soluble vitamins. The peroxidative
stress in newborn was found to be significantly less as compared to their mothers. A positive correlation of ascorbic acid
and α-tocopherol levels between mother and newborn reflects that their status in mother does influence the newborn status. 相似文献
43.
44.
Ritu Sharma Mridula Mahajan Ravi Kant 《Indian journal of clinical biochemistry : IJCB》2004,19(1):10-13
Serum total lipids (cholesterol and triglyceride), lipoproteins (VLDL, LDL and HDL) and Apolipoprotein-B levels of normal
healthy individuals (n=25) and coronary artery disease patients (n=25) were estimated. The objective of the present study
was to ascertain the role of apo-B in causation and inheritance of coronary artery disease. It was observed that on an average
serum total cholesterol and triglyceride more than 200 mg/dl bring the individuals to a risk of coronary artery disease (CAD)
irrespective of the age. CAD patients achieved this value at an early age (35–45 years). Similarly VLDL and LDL levels were
found to be significantly raised in CAD patients when compared to that of age matched normal individuals, with patients achieving
risk values at an early age. HDL levels were found to be significantly lower in CAD patients as compared to normal individuals.
Serum apo-B levels were significantly raised in CAD patients as compared to age matched normal individuals. Patients with
positive family history of CAD had raised serum apo-B levels than those having negative family history. A positive coefficient
of correlation was observed between serum apo-B and LDL levels suggesting that more the number of Apo-B particles, more will
be the synthesis of atherogenic particle (LDL). Patients with negative family history had serum apo-B levels closer to those
of normal individuals and in these individuals HDL levels were found to be significantly lowered, suggesting that loss of
scavenger role of HDL could be the risk factor responsible for the causation of CAD in these patients, with negative family
history of coronary artery disease. 相似文献
45.
46.
Gora Dadheech Sandhya Mishra Shiv Gautam Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2006,21(2):34-38
A disturbance in the antioxidant defense system including α-tocopherol, ascorbic acid and reduced glutahtione metabolism due
to free radical induced oxidative injury has been implicated in various neuro-psychiatric disorders. The roles of these antioxidants,
changes in their blood levels and correlation with oxidative stress were studied in a common psychiatric illness Schizophrenia.
Fifty-eight subjects of either sex ranging in age from 18–60 years divided into two age groups (≤40 and >40 years) diagnosed
for schizophrenia, and forty age and sex-matched normal subjects as controls were included in the study. Blood samples were
analyzed for malondialdehyde (MDA), α-tocopherol, total ascorbic acid (TAA), dehydro ascorbic acid (DHAA), reduced ascorbic
acid (RAA), leucocyte ascorbic acid (LAA) and reduced glutathione (GSH). A decrease in the levels of α-tocopherol, total ascorbic
acid and reduced glutathione was found in schizophrenics compared to normal controls. Further a significant rise in oxidative
stress and decreased antioxidant status was observed in the chronic stage of schizophrenia as compared to those in acute condition.
A significant rise in dehydroascorbic acid with concomitant fall in reduced ascorbic acid suggests scavenging action of ascorbic
acid and its utilization with increased oxidative stress as indicated by high blood malondialdehyde levels. Leucocyte ascorbic
acid, a better index of ascorbic acid status was also found to be reduced in schizophrenics, suggesting depletion of body
stores of ascorbic acid and the condition worsened with advancing age. 相似文献
47.
Praveen Sharma Sandhya Mishra Peeyush Ajmera Sandeep Mathur 《Indian journal of clinical biochemistry : IJCB》2005,20(1):145-149
As antioxidants play a protective role in the pathophysiology of diabetes and cardiovascular diseases, understanding the physiological
status of antioxidant concentration among people at high risk for developing these conditions, such as Metabolic Syndrome,
is of interest. In present study out of 187 first degree non-diabetic relatives and 192 non-diabetic spouses, 33.1% and 19.7%
were found to have metabolic syndrome respectively. Subjects with metabolic syndrome (≥3 risk factors) had poor antioxidants
status as reflected by significantly low levels of vitamin A, C & E and significantly increased (p<0.01) oxidative stress
as compared to those without metabolic syndrome. At the same time serum insulin levels and insulin resistance were found to
be significantly high (p<0.001) in metabolic syndrome. A strong positive correlation (r=0.946; p<0.001) between oxidative
stress and insulin resistance was observed in metabolic syndrome. Low levels of antioxidants and increased oxidative stress
with insulin resistance in metabolic syndrome suggests that besides therapeutic life style changes (TLC) as suggested in ATP
III guidelines inclusion of antioxidant vitamins, fruits and vegetable could be beneficial to ward off the consequences of
metabolic syndrome. 相似文献
48.
Diabetics showed significantly raised levels of total and LDL cholesterol, (257.0±68.88 mg% 173.5±67.7mg% respectively) compared
to controls matched with age, sex and socioeconomic status. No significant difference was observed in these parameters in
diabetics with and without retinopathy. 相似文献
49.
Study on arsenic level in ground water of Delhi using hydride generator accessory coupled with atomic absorption spectrophotometer 总被引:1,自引:0,他引:1
Sanjeev Lalwani T. D. Dogra D. N. Bhardwaj R. K. Sharma O. P. Murty Aarti Vij 《Indian journal of clinical biochemistry : IJCB》2004,19(2):135-140
Surveillance of drinking water is essentially a health measure intended to protect the public from water borne diseases. Hydride
generator accessory coupled with atomic absorption spectrophotometer was used to analyze arsenic level in 49 ground water
samples collected from different areas of Delhi. Arsenic level in ground water samples was in the range of 0.0170 to 0.100
ppm (Mean-0.0431, Standard Deviation-0.0136, Std. error of Mean-0.00194) with minimum concentration at Raney Well No. 7 (0.0170
ppm) and maximum at Kotla Mubarak Pur (0.100 ppm). Arsenic containing sediments and percolation of chemicals into soil as
the result of dumping of garbage rich in chemicals into open landfills could be the possible source of arsenic in ground water
of Delhi. Extensive survey and continuous monitoring is required to be made to assess the magnitude of problem and earlier
intervention. 相似文献
50.
Umesh Sharma Filipe Jitoko Setareki S. Macanawai 《International Journal of Disability, Development & Education》2018,65(6):614-630
In recent years, countries of the Pacific have been moving strongly towards enhancing inclusive educational practices within a previously segregated education system. Through the Pacific Education Development Framework (PEDF) approved by 14 Pacific Island Education Ministers in 2009, the implementation of regional policies of inclusive education is a priority. To ensure that progress is measurable, these countries have been working collaboratively with several Australian institutions to develop a set of contextually appropriate indicators for measuring disability-inclusive education. This article describes the process adopted in developing these indicators and initial findings regarding the key outcomes. The research is guided by three key principles of collaboration, a need for systemic change and ‘nothing about us without us’. The process adopts a three-stage approach which is outlined and key issues and implications discussed. 相似文献