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31.
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Pongamia pinnata, commercially important tree species used to produce biofuels, is known for its multipurpose benefits and its role in agro-forestry. Present study examines the amenability of vegetative propagation and effect of maturation in candidate plus tree P. pinnata through rooting of stem cuttings treated with varying concentrations and combinations of auxins. The performance of the cuttings was evaluated using SAS GLM software and the data were analyzed as a one-way classified data with and without sub sampling for inferring auxin concentration that can be included in programmes aimed at genetic improvement of the tree species. All auxin treatments promoted sprouting and at lower concentrations triggered/enhanced rooting of cuttings. The effectiveness was in the order of IBA > NAA > IAA when applied singly. IBA at 4.92 mM was found to be most effective where rooting percentage and number of roots were significantly higher (P < 0.01) than in control. However higher concentrations of auxins above 7 mM in general inhibited the rooting of cuttings. The interaction among auxins was found to be effective in root induction and differentiation and the most stimulating effects were observed in three-component mixture. The effect of other cutting characteristics such as juvenility and cutting position on rooting is also discussed.  相似文献   
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Mammalian gastric lipases are stable and active under acidic conditions and also in the duodenal lumen. There has been considerable interest in acid stable lipases owing to their potential application in the treatment of pancreatic exocrine insufficiency. In order to gain insights into the domain movements of these enzymes, molecular dynamics simulations of human gastric lipase was performed at an acidic pH and under neutral conditions. For comparative studies, simulation of dog gastric lipase was also performed at an acidic pH. Analyses show, that in addition to the lid region, there is another region of high mobility in these lipases. The potential role of this novel region is discussed.  相似文献   
35.
Dihydroxo-bridged dicopper(II) complexes [(Cu(phen))(2)(mu-OH)(2)](ClO(4))(2) (1), [(Cu(dpq))(2)(mu-OH)(2)](ClO(4))(2) (2) and [(Cu(dppz)(DMF))(2)(mu-OH)(2)](PF(6))(2) (3), where phen, dpq and dppz are 1,10-phenanthroline, dipyridoquinoxaline and dipyridophenazine, respectively, are prepared and their DNA binding and cleavage properties studied. Complex 3 has been structurally characterized by X-ray crystallography. The complexes have a (Cu(2)(mu-OH)(2))(2+) core with an essentially planar arrangement of two CuN(2)O(2) basal planes. The complexes are avid binder to calf thymus DNA (K(app) value of 4.8 x 10(6) and 5.9 x 10(6) M(-1) for 2 and 3, respectively, from ethidium displacement assay) and exhibits significant cleavage of supercoiled (SC) pUC19 DNA in dark in presence of mercaptopropionic acid. Besides, the dpq and dppz complexes display photo-induced DNA cleavage on UV (312 nm) and red light (632.8 nm) irradiations in absence of any additives. Mechanistic investigations reveal minor groove binding for the phen and dpq complexes, and major groove preference for the dppz species. The oxidative DNA cleavage reactions in presence of mercaptopropionic acid as a reducing agent involve hydroxyl radicals. The photo-cleavage reactions at UV light involve singlet oxygen as the reactive species, while similar reactions on red light irradiation (632.8 nm) proceed through the formation of hydroxyl radical. The complexes show significant DNA hydrolase activity in absence of any additives under dark reaction conditions.  相似文献   
36.

Background  

Majority of tumours occurring in minor salivary gland are malignant. Pleomorphic adenoma is of rare occurrence in parapharangeal space.  相似文献   
37.

Background  

Although direct infiltration of papillary carcinoma of thyroid to larynx, trachea and esophagus is well recognized, lymphatic and vascular metastases to larynx and hypopharynx have rarely been reported.  相似文献   
38.
Spore proteins of the microsporidian Nosema bombycis, from the silkworm Bombyx mori, were analysed by SDS–polyacrylamide gel electrophoresis. The protein profile of partially solubilized spores showed three major peptide bands of molecular weight 68, 94 and 100 kDa. On complete solubilization, it showed peptide bands ranging from 17 to 68 kDa. Attempts to purify the 17 kDa infection-specific protein showed aggregation of this protein to higher molecular size proteins. Partial peptide analysis of the different peptides exhibited similar patterns suggesting the probablity of processing during the infective cycle. Reconstitution assay showed the reversible nature of this processing. N-terminal sequencing showed homology to heat shock proteins. The low molecular weight 17 kDa protein also showed very high protease activity.  相似文献   
39.
Natural killer (NK) cells belong to the innate arm of the immune system and though activated NK cells can modulate immune responses through the secretion of cytokines, their primary effector function is through target cell lysis. Accordingly, cytotoxicity assays are central to studying NK cell function. The 51Chromium release assay, is the “gold standard” for cytotoxicity assay, however, due to concerns over toxicity associated with the use and disposal of radioactive compounds there is a significant interest in non-radioactive methods. We have previously used the calcein release assay as a non-radioactive alternative for studying NK cell cytotoxicity. In this study, we show that the calcein release assay varies in its dynamic range for different tumor targets, and that the entrapped calcein could remain unreleased within apoptotic bodies of lysed tumor targets or incompletely released resulting in underestimation of percent specific lysis. To overcome these limitations, we developed a novel cytotoxicity assay using the Cellometer Vision Image Cytometer and compared this method to standard calcein release assay for measuring NK cell cytotoxicity. Using tumor lines K562, 721.221, and Jurkat, we demonstrate here that image cytometry shows significantly higher percent specific lysis of the target cells compared to the standard calcein release assay within the same experimental setup. Image cytometry is able to accurately analyze live target cells by excluding dimmer cells and smaller apoptotic bodies from viable target cell counts. The image cytometry-based cytotoxicity assay is a simple, direct and sensitive method and is an appealing option for routine cytotoxicity assay.  相似文献   
40.
Chronic feeding of fructose to normal rats causes impaired glucose tolerance, loss of tissue sensitivity to insulin, hyperinsulinemia and hypertension. -Lipoic acid (LA), a co-enzyme known for its potent antioxidant effects, stimulates insulin-mediated glucose uptake in clinical and experimental diabetes. The purpose of this study was to examine whether LA can mitigate fructose-induced insulin resistance and associated abnormalities. Male Wistar rats of body weights 150–170 g were divided into 4 groups containing 12 rats each. Control rats received a control diet containing starch and water ad libitum. Fructose rats received a fructose-enriched diet (>60% of total calories). Fructose + LA rats received a fructose diet and LA (35 mg/kg b.w.) intraperitoneally. Control + LA rats received a normal diet and LA (35 mg/kg b.w.) intraperitoneally. After the treatment period of 20 days, blood pressure (BP) was measured. Oral glucose-tolerance test, insulin-sensitivity index, urea and creatinine clearance tests, and plasma and urinary sodium and potassium levels were analysed. Kallikrein activity and nitrite content were assayed. Additionally, the activities of RBC-membrane Na+/K+ ATPase and Ca2+ ATPase enzymes were assayed. Fructose rats showed increased BP, decreased glucose tolerance, decreased insulin sensitivity and altered sodium and potassium levels and renal clearance. LA supplementation mitigated these alterations. The increase in BP was attenuated and the levels of biochemical parameters were brought close to normal. The BP-lowering effect of LA in fructose rats may be related to improvement in insulin sensitivity.Communicated by L.C.-H. Wang.  相似文献   
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