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81.
In this paper,the effect of using hindered phenol,zinc dialkyl dithiocarbamate(ZDDC),tolutriazole derivative and combinations thereof to inhibit a blend of commodity Canola Oil and high oleic content soybean oil(1:1) was investigated.Specifically,oils were oxidized by bubbling oxygen through 300 mL samples heated at 95 ℃.Antioxidant depletion rates were indirectly monitored by measuring oxidation induction times(OIT) as determined by Pressure Differential Scanning Calorimetry(PDSC).Preliminary data indicate...  相似文献   
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Prosopis alba is an arboreal legume that occurs naturally in Argentine. Its fruits (algarroba or Prosopis pods) are dried or roasted, ground and then used in foods and feeds. The influence of roasting process on the water sorption isotherms of Prosopis pod flour at three storage temperatures was studied. The equilibrium data for each sorption isotherm were determined by the standard static gravimetric method. Experimental values were fitted to the BET and GAB sorption models. Type II isotherms were obtained according to Brunauer classification. The calculated isosteric heats of sorption (Qs) near the monolayer moisture content were 7.30 and 7.68 kJ/mol for raw and roasted flour, respectively. The results showed that roasting did not significantly change the behavior of the products with regard to water adsorption, although a slight reduction of the tendency to humectation was observed, this being somewhat less spontaneous. In this aspect, the stability of Prosopis flour is similar in the raw and roasted states.  相似文献   
84.
In 1998, Cubist Pharmaceuticals patented a series of aminoacyl tRNA synthetase (aaRS) inhibitors based on aminoacyl sulfamoyladenosines (aaSAs), in which the adenine was substituted by aryl-tetrazole moieties linked to the ribose fragment by a two-carbon spacer. Although potent and specific inhibitors of bacterial IleRS, these compounds did not prove successful in vivo due to low cell permeability and strong binding to serum albumin. In this work, we attempted to improve these compounds by combining them with microcin C (McC) or albomycin (i.e., siderophore-drug conjugate (SDC)) transport modules. We found that aryl-tetrazole variants of McC and albomycin still lacked antibacterial activity. However, these compounds were readily processed by E. coli aminopeptidases with the release of toxic aaRS inhibitors. Hence, the lack of activity in whole-cell assays was due to an inability of the new compounds to be taken up by the cells, thus indicating that the nucleotide moieties of McC and albomycin strongly contribute to facilitated transport of these compounds inside the cell.  相似文献   
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BACKGROUND AND PURPOSE: We describe four cases of aneurysmal rupture during embolization with Guglielmi electrodetachable coils (GDCs) in an attempt to identify those aneurysms whose rupture during embolization represents a life-threatening risk; our emphasis is on emergency management, in particular, ventriculostomy. METHODS: Medical records were reviewed retrospectively for 91 aneurysms treated with GDCs 0 to 21 days after subarachnoid hemorrhage. Rupture was ascertained by the presence of extravascular effusion of contrast medium. RESULTS: Of the perforated aneurysms, two involved the anterior communicating artery, one the posterior inferior communicating artery, and one the basilar artery. Only two patients, whose aneurysms were located in the posterior fossa, had major complications (arterial hyperpressure, mydriasis, angiographically documented circulatory arrest or slowing). One of these patients died and the other improved after emergency ventriculostomy. CONCLUSION: Aneurysmal perforation during embolization may be accompanied by severe intracranial hypertension, which causes either a decrease or arrest of cerebral perfusion, the duration of which determines clinical outcome. Emergency ventriculostomy (which should be performed in the angiographic suite) is an effective means to reduce intracranial pressure. Recognition of aneurysms associated with a high risk of mortality by rupture in the course of embolization (recently ruptured small aneurysms, posterior fossa aneurysms, associated ventricular dilatation, massive cisternal hemorrhage) and use of proper logistics should ensure the effective management of this devastating complication.  相似文献   
87.
Using field experiments, we investigated the development of parent-offspring recognition in the thick-billed murre, Uria lomvia. Cross-fostering experiments (N=73) showed that the likelihood of parents accepting a foreign chick decreased with chick age. Simultaneous-choice playback experiments demonstrated that chicks discriminate between the calls of their parents and both strange and familiar adult conspecifics from as early as 3 days old. In presentation experiments with chicks of fledging age (>/=14 days), adults responded more strongly to the calls of their own chicks than to other familiar chicks from the same breeding ledge. Results are consistent with those of earlier studies of parent-offspring recognition in the congeneric and ecologically similar common murre, U. aalge, which were among the first to suggest that parent birds and their chicks can identify each other's calls. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.  相似文献   
88.
The McGill Object Relations Scale (MORS) is an instrument for assessing levels of drive-based object relations along a continuum of positions representative of psychosexual development. Its theoretical foundations as well as empirical antecedents are presented, and its rating procedure is demonstrated through a case application. The MORS was applied, by five experienced psychiatrists, to 67 adult patients seeking psychoanalytic psychotherapy, in order to assess interrater reliability, internal structure, and construct validity. Results indicate that overall maturity of object relations stems from structural indices of self-object differentiation determined by a particular configuration of many positions, rather than from the thematic aspects included in the individual psychosexual positions.  相似文献   
89.
Summary Mapping of science and technology can be done at different levels of aggregation, using a variety of methods. In this paper, we propose a method in which title words are used as indicators for the content of a research topic, and cited references are used as the context in which words get their meaning. Research topics are represented by sets of papers that are similar in terms of these word-reference combinations. In this way we use words without neglecting differences and changes in their meanings. The method has several advantages, such as high coverage of publications. As an illustration we apply the method to produce knowledge maps of information science.  相似文献   
90.
A novel parallel architecture which combines the processing power of VLSI technology with the communication advantages of optical interconnects is presented for parameter estimation based on the square root covariance Kalman filter.<>  相似文献   
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