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981.
This paper examines the terminological confusion underlying the study of information use, and reviews the major studies in the field. The conclusion is that confusion in research methods is inextricably linked to a lack of clarity in terminology. Attention is drawn to the significance of different social and cultural contexts in shaping ‘information needs’, and a research scheme is evolved for the study of users of ‘professional information’ in Poland. 相似文献
982.
Farhana Zahir Shameem J Rizvi Soghra K Haq Rizwan H Khan 《Indian journal of clinical biochemistry : IJCB》2006,21(2):149-152
Mercury pollution and acute neurotoxicity of mercury is well known. The recent reports suggest the adverse effect of low dose
mercury, though the available literature is still silent on its mechanism. This study was therefore undertaken to probe the
effect of low dose methyl mercury induced heavy metal toxicity on free radical stress and its impact on behaviour of male
albino rats. Male albino rats were exposed to 1 mg/kg body wt of methylmercury chloride for seven days, on day 8 they were
tested for motor and memory functions. They were sacrificed later for biochemical estimations for rate of lipid peroxidation,
nucleic acids, proteins in cerebrum, cerebellum and brain stem. There was an increase in the rate of lipid peroxidation showing
methyl mercury induced free radical stress. The motor and memory functions demonstrated a clear decline, besides there was
a lowering in the levels of nucleic acids and proteins as compared to controls. The results are important in view of recent
reports that methyl mercury induced free radical stress results in early ageing and may serve as an initiating factor more
specifically for neurodegenerative disorders like Alzeihemer's disease and dementias. The current findings support the notion
that incorporating dietary antioxidants like curcumin, ascorbic acid and α-tocopherol in routine diet from early age may help
combat the risk of developing such disorders in ensuing years. 相似文献
983.
Gamma Glutamyl Transferase (γ-GT) is a microsomal enzyme. Its activity in serum is assayed in alcoholics with liver abscess
and alcoholics without liver abscess after screening by ultrasonography. The enzyme activity in serum is increased by 334%
in the patients with liver abscess compared to normal control subjects (p<0.0001), and 172% when compared to patients with
chronic alcoholism without liver abscess (p<0.0001). The enzyme activity was increased by 59.3% in the serum of patients without
liver abscess compared to the normal control subjects (p<0.001). Measurement of γ-GT in serum appears to be a sensitive index
in the diagnosis of alcoholics with liver abscess. 相似文献
984.
P. P. Singh K. H. Komleh A. K. Pendse Rajkiran R. C. Gupta 《Indian journal of clinical biochemistry : IJCB》1992,7(1):57-59
Serum (200.6±64.8 mg/dl) and urinary zinc (1186.0±265.5 mg/l.) of zinc miners at Zawar were significantly higher as compared to zinc smelter workers (Serum 89.7±9.9. mg/dl; Urine 590.0±32.1 mg/l.). Debari and Udaipur residents (Serum 104.0±18.6 mg/dl; Urine 735.0±180.2 mg/l.). This was most likely attributable to higher dietary zinc intake by zinc miners due to higher zinc content of foodstuffs grown in Zawar areas as compared to Debari and Udaipur. 相似文献
985.
986.
Y. P. Bhandary K. N. Krithika Sandeep Kulkarni M. V. R. Reddy B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2006,21(1):1-7
Lymphatic filariasis caused mainly by infection fromW. bancrofti andB. malayi remains a major cause of clinical morbidity in tropical and subtropical countries. Analysis ofB. malayi mf, infective larval and adult worm lysates for the activity of enzymes led to the demonstration of activities of three key
enzymes of carbohydrate metabolism viz., Malate dehydrogenase (MDH), Malic enzyme (ME) and Glucose-6-phosphate dehydrogenase
(G6PDH) in all the three stages of the parasite. The specific activity of all the three dehydrogenases was significantly high
in mf lysate compared to their activity in lysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel
to their activity inlysates of the other two stages (P<0.001). Analysis by native polyacrylamide gel electrophoresis (PAGE)
using 7.5% non-gradient gel showed the presence of two isoforms of each of the three enzymes (MDH, ME & G6PDH) in mf lysate,
while only one form of each enzyme was present in L3 larval and adult worm lysates. Further proteolytic enzyme activity was demonstrated both in microfilarial and infective larval
lysates ofB. malayi. While both mf and L3 larval lysates showed optimal protease activity at alkaline pH of 9.0, the mf lysate showed increased activity also at pH
3.0. The infective larval lysate was markedly inhibited by Tosylamide-L-Phenylalanine chloromethyl ketone (TPCK), a thiol
protease inhibitor, while the protease activity in mf lysate was significantly inhibited by both TPCK and a serine protease
inhibitor Phenyl Methyl Sulphonyl Flouride (PMSF). In sodium do-decyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE),
using gelatin copolymerized gel, the microfilarial lysate showed 3 protease molecules of 40 kDa, 180 kDa and 200 kDa and the
L3 larval lysate had 6 protease molecules of 18, 25, 37, 49, 70 and 200 kDa size. 相似文献
987.
988.
Andrea L. Kavanaugh Debbie Denise Reese John M. Carroll Mary Beth Rosson 《The Information Society》2005,21(2):119-131
Communities with high levels of social capital are likely to have a higher quality of life than communities with low social capital. This is due to the greater ability of such communities to organize and mobilize effectively for collective action because they have high levels of social trust, dense social networks, and well-established norms of mutuality (the major features of social capital). Communities with “bridging” social capital (weak ties across groups) as well as “bonding” social capital (strong ties within groups) are the most effective in organizing for collective action. People who belong to multiple groups act as bridging ties. When people with bridging ties use communication media, such as the Internet, they enhance their capability to educate community members and to organize, as needed, for collective action. This article summarizes evidence from stratified household survey data in Blacksburg, VA, showing that people with weak (bridging) ties across groups have higher levels of community involvement, civic interest, and collective efficacy than people without bridging ties among groups. Moreover, heavy Internet users with bridging ties have higher social engagement, use the Internet for social purposes, and have been attending more local meetings and events since going online than heavy Internet users with no bridging ties. These findings may suggest that the Internet—in the hands of bridging individuals-is a tool for enhancing social relations and information exchange, and for increasing face-to-face interaction, all of which help to build both bonding and bridging social capital in communities. 相似文献
989.
R. L. Gupta K. Ramachandran Monika J. S. Chowhan 《Indian journal of clinical biochemistry : IJCB》1996,11(1):59-61
Urinary excretion of beta-aminoisobutyric acid (BAIB), was determined in 28 active and 12 inactive bladder cancer patients.
Mean excretion of BAIB was higher in active cancer patients-187.8 mg/24 hours whereas it was 120.4 mg/24 hours in inactive
cancer patients. The increased BAIB excretion in both disease groups was independent of tumour stage. BAIB appears to be a
useful diagnositic aid in the assessment of bladder cancer patients. 相似文献
990.
K. S. Motghare Anil Bhutey B. B. Murrhar Madhur Gupta A. W. Meshram Y. Balsubramanium 《Indian journal of clinical biochemistry : IJCB》2001,16(2):213-215
With the growing interest in the concept of free radicals in the pathogenesis of myocardial ischemia, it was thought worthwhile
to study the changes in lipid peroxides and antioxidant enzyme glutathione peroxidase (GPx) in ischemic heart disease (IHD).
The study was carried out on 76 patients of IHD-38 of acute myocardial infarction (AMI) and 38 of stable ischemic heart disease
(SIDH). They were age and sex matched with 38 normal healthy controls. A significant increase (p<0.001) in lipid peroxides
as malondialdehyde (MDA) (5.9±0.7 mmol/L) and a decrease in GPx (24.6±2.2 U/gmHb) was found in patients of AMI when compared
with controls. There was no significant difference in these values in SIHD. Thus this study confirms the earlier findings
that MDA and GPx are useful parameters in IHD and their magnitude is dependent on severity and/or duration of ischemia. We
suggest that these tests would be of use in smaller institutions with limited facilities. 相似文献