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Drawing on institutional theory, we examine how institutions have influenced technology development trends in the U.S. since the mid-19th century. Based on an inductive analysis of the history of technology development and corporate R&D, we show that both formal and informal institutional rules and constraints played a role in the initial rise of markets for technology, their decline during the early-20th century, and their eventual return at the end of the 20th century. We also find that formal and informal institutions influenced the widespread adoption of in-house R&D labs during the mid-20th century. Our study integrates insights from both the economics and sociology branches of institutional theory. This perspective is particularly useful to analyze historical phenomenon and shifts in trends across long time periods. 相似文献
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Ramesh Chander A. K. Khanna Kanwal Raj A. K. Rastogi 《Indian journal of clinical biochemistry : IJCB》2005,20(1):153-159
Indian black tea; CTC leaf and dust, produced by Tata Tea Limited, Kolkata, (India) was studiedin vitro as potential scavenger of oxygen free radicals. Super oxide anions were generated in a system containing xanthine—xanthine
oxidase (enzymic system) and by NADH- phenozine methosulphate (non enzymic system). Anions were assayed in terms of uric acid
formation and reduction of nitroblue tetrazolium salt, which were shown to be suppressed by tea extracts. Extracts from both
leaf and dust also inhibted the formation of hydroxyl radicalsin vitro in the enzymic system comprising hypoxanthine—Cu+2—sodium ascorbate and xanthine oxidase and in non enzymic system of deoxyribose—Cu+2—sodium ascorbate and H2O2 as well as the Cu+2 induced lipid peroxidation in human low density lipoprotein. Feeding with black tea in normal rats for sixty days increased
their antioxidant activity and their liver microsomes were shown to be protected against peroxidation of lipids as stimulated
by metal ions with enzymic or non enzymic reactants. Furthermore feeding with tea extracts in normal as well as triton WR—1339
induced hyperlipidemic rats caused decrease in their plasma levels of total cholesterol, phospholipids and triglycerides.
The antioxidant and lipid lowering activities of both extracts from CTC leaf and dust tea was comparable and may be due to
the presence of natural products like catechin and others. 相似文献
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The level of sialic acid in the obese polymorphonuclear leukocytes (PMNL) was found to be significantly reduced as compared to normal. Activity of sialic acid degrading enzyme, sialidase, was found to be increased in the obese state. Restoration in both sialic acid content and sialidase activity was also evidenced in the PMNL of treated obese patients. 相似文献
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Sonika Gupta Niraj Shende Swati Banerjee Satish Kumar M. V. R. Reddy Bhaskar C. Harinath 《Indian journal of clinical biochemistry : IJCB》2002,17(1):5-8
Tuberculosis remains major health problem in India and developing countries Immunodiagnosis has important role in screening,
diagnosis and management of tuberculosis. SEVA TB ES-31 antigen has shown potential in detecting tuberculous IgG antibody
in earlier studies from our laboratory. In the present study we have analysedSEVA TB ES-31 antigen specific immunoglobulinsIgM, IgA and IgG in clinically and bacteriologically confirmed pulmonary tuberculosis cases to determine the usefulness of specific immunoglobulin
class in the diagnosis of patients attending the hospital.
Of the 30 cases of pulmonary tuberculosis 25 (83.3%) were positive for IgG, 19 (63.3%) for IgM and 16 (53.3%) for IgA. On
combining IgG and IgM positivity, sensitivity was increased to 93.3%. While combining IgG and IgA positivity, sensitivity
increased to 90%. However specificity was decreased to 66.6% and 70% for both of these combinations respectively. It could
be envisaged from this study that IgG antibody detection against ES-31 antigen showed acceptable sensitivity (83.3%) and specificity
(86.6%) compared to IgM or IgA alone or in combination. When immune responses were analysed according to degree of sputum
positivity, IgG response was observed to be predominant in all grades, compared to IgM or IgA antibody. The addition of IgM
or IgA as an adjunct test increases the sensitivity but at the cost of specificity. Hence the detection of IgG alone is more
useful compared to IgM or IgA assay, in detecting tuberculosis disease cases coming to the hospital. 相似文献
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Raj Mestry 《Africa Education Review》2019,16(6):94-110
AbstractAlthough the South African government has made numerous strides in addressing equity and social justice in education, significant inequalities still exist in learner performance, especially in many impoverished schools. One of the reasons cited for poor learner achievement is the ineffective leadership role of school management teams (SMTs). This article reports on a study that explored the instructional leadership role of SMTs of public schools with the view to closing the achievement gap in poor performing schools. To gain better insights into the SMTs’ realities and experiences of their work as curriculum leaders, qualitative research located within the interpretivist paradigm was undertaken. The findings revealed that SMTs of impoverished schools exhibit consistently low to moderate instructional leadership competencies which ultimately affect student learning. In order to close the achievement gap in poor performing schools, SMTs should play a more pronounced instructional leadership role by leading and managing core curriculum matters and educational resources effectively and efficiently. 相似文献
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Raj Aggarwal 《Innovative Higher Education》1987,11(2):123-135
This paper is a study of the adaption of a typical corporate strategic planning process to a university setting. This midwestern state university with over 22,000 students and a number of doctoral, masters, and baccalaureate programs, found that an ongoing planning process with a yearly cycle offers it a number of advantages not avail-able with its prior approaches. It also found that strategic planning is a culture that takes time before it becomes pervasive in any organization.The views expressed in this paper are solely those of the author and do not necessarily represent the viewpoints of any organization. 相似文献
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Izatus Shima Taib Siti Balkis Budin Seri Maseran Siti Nor Ain Jamaludin Mohamed Santhana Raj Louis Srijit Das Sulaiman Sallehudin Nor Fadilah Rajab Othman Hidayatulfathi 《Journal of Zhejiang University. Science. B》2009,10(11):813-819
Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, che-mopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinoeyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage. 相似文献
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P. Sharma M. Bose Isa Mohd S. Bagdi H. G. Raj 《Indian journal of clinical biochemistry : IJCB》2000,15(2):83-87
Genomic DNA from a clinical isolate ofMycobacterium avium-intracellulare complex was purified and cloned in PBR 322 at the tetracycline resistance site using Bam HI restriction enzyme. A 16 kb cloned
fragment was purified, radiolabeled and used as a probe. Genomic DNA isolated from nineteen MAC strains, threeM. tuberculosis strains and oneM. kansasii strain were digested with Eco RI restriction enzyme, Southern blotted and hybridized with the 16 kb cloned and labeled fragment.
Twelve MAC strains showed positive hybridization although five strains gave faint signals. Positive hybridization was noted
in two out of the threeM. tuberculosis strains, possibly due to shared DNA homology. No signal was received from the singleM. kansasii strain used in this study. 相似文献