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Serum cholesterol, triglycerides and total lipids were estimated in twelve students exposed to varying degree of examination stress. Serum cholesterol and triglycerides exhibited a rise proportional to degree of examination stress whereas total lipids exhibited an initial rise followed by a fall. Values of all these parameters attained control level when the stress was over. The rise in serum cholesterol and triglycerides seems to be due to stress induced changes in hormonal levels and peripheral lipolysis respectively.  相似文献   
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The present investigation was undertaken to evaluate the potential diuretic activity of Boerhaavia verticillata . The ethanolic and aqueous extracts of B. verticillata were administered in doses of 50 and 100 mg/kg, i.p., to normal and adult albino rats, which were monitored over a period of 24 h. Experimental results confirmed that both the ethanol and aqueous extracts have diuretic properties, but the ethanol extract seems to have less diuretic and natriuretic activity than the aqueous extract.  相似文献   
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An efficient, reliable and reproducible plant regeneration protocol was developed for Lawsonia inermis L. using mature nodal explants. Shoot proliferation (81.6 %) with 7.8 shoots/explant was achieved on Murashige and Skoog’s (MS) medium supplemented with 1.0 mg l?1 6-benzyladenine. Shoot numbers were up-scaled by inducing multiple shoots from axenic nodal segments derived from the primary shoots on the shoot regeneration medium. Thus the authors could achieve ca. 129–134 shoots from single nodal explant. Ninety-three percent rooting of in vitro regenerated shoots was achieved on growth regulator free half-strength MS medium. Regenerated plantlets were successfully transferred to soil with 85 % survival rate. Genetic stability analyses of the in vitro regenerated plants using random amplified polymorphic DNA and inter simple sequence repeat markers revealed a homogeneous amplification profile for all micropropagated plants. This is the first report that evaluates the use of molecular markers to establish genetic fidelity of micropropagated L. inermis for the rapid clonal multiplication and true-to-type production of plant for attaining the ever increasing demand in pharmaceutical industries.  相似文献   
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Substituting an ion of different size from that of the host element introduces lattice strain and defects. However, this mismatch may be significantly reduced by substituting an additional ion with a compensating size relative to the dopant. Such a double substitution might offer better solubility irrespective of the local distortions as well as the formation of defects in the valence states. Fe-substituted ZnO has been widely reported with conflicting results primarily arising from lack of chemical and structural homogeneity originating from preparation techniques, compositional fluctuations, and equivocal comprehension of actual solubility limits of the dopants. In this study, Ag ion has been incorporated in Fe-substituted ZnO to compensate the ionic size of Zn1−x[Fe0.8Ag0.2]xO (0 ≤ x ≤ 0.03125) by determining the solubility limit of the homogeneous material and their corresponding structural, mechanical, optical and magnetic properties have been investigated thoroughly. Co-substitution rearranges the lattice and leads to better crystal structures with tunable properties related to the amount of substitution.

Substituting an ion of different size from that of the host element introduces lattice strain and defects.  相似文献   
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Objective:To examine the individual and synergistic anti-listcrial effect of nisin and leaf essential oil of Metasequoia glyptostroboides(M.glyptostroboides) against one of the leading foodhorne pathogens Listeria monocytogenes(L.monocytogenes) ATCC 19116 in milk samples.Methods:The whole(8%),low(1%) and skim(no fat content) milk samples were inoculated with L.monocytogenes ATCC 19116 along with leaf essential oil of M.glyptostroboides or nisin alone as well in eomhinations.Results:In this study,the leaf essential oil at the concentrations of 2% and 5% revealed strong anti-listerial effect against L.monocytogenes ATCC 19116 in all categories of milk samples.Nisin at the concentrations of 250 and 500 IU/mL displayed a strong inhibitory effect against ATCC 19116 as compared to the control group.Additionally,synergistic combinations of leaf essential oil(1%) and nisin(62.5,125.250 and 500 IU/mL) also had a remarkable anti-listerial synergism in all the tested milk samples including whole,low and skim milk after 14 days.Conclusions:As a major finding,the leaf essential oil of M.glyptostroboides might he a useful candidate for using in food industry to control the growth of foodhorne pathogenic bacteria as confirmed by its potent anti-listerial Synergistic effect with nisin against L.monocytogenes ATCC 19116 in different milk samples.  相似文献   
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