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41.
To assess the value of routine preoperative chest x-ray films in pediatric patients, a prospective study of 1,500 patients, ages newborn to 19 years, was undertaken. Of all the patients, 7.5% demonstrated at least one roentgenographic abnormality, with 4.7% of the patients demonstrating a totally unsuspected significant roentgenographic anomaly. In 3.8% of the patients, surgery was eihter postponed or cancelled or the anesthetic technique was altered as a result of the roentgenographic finding. It is believed that the routine preoperative chest film is justified if the film is evaluated before surgery and the results clinically followed up. 相似文献
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ChemCam, a laser-induced breakdown spectroscopy (LIBS) instrument on the Mars Science Laboratory rover, will analyze the chemistry of the martian surface beginning in 2012. Prior to integration on the rover, the ChemCam instrument collected data on a variety of rock types to provide a training set for analysis of data from Mars. Models based on calibration data can be used to classify rocks via multivariate statistical techniques such as partial least squares-discriminant analysis (PLS-DA). In this study, we employ a version of PLS-DA in which modeling is applied in a defined classification flow to a variety of geological materials and compare the results with the traditional PLS-DA technique. Results show that the modified algorithm is more effective at classifying samples. 相似文献
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JL Kerwin JK MacKichan MJ Semon AM Wiens CC DeRose JJ Torvik 《Canadian Metallurgical Quarterly》1996,31(11):1179-1188
Lagenidium giganteum, a facultative parasite of mosquito larvae, cannot synthesize sterols, and requires an exogenous source of these lipids in order to enter its reproductive cycle. This parasite grows vegetatively in the absence of sterols, but requires cholesterol or structurally related compounds to produce motile zoospores, which are the only stage capable of infecting mosquitoes. Sterols structurally related to cholesterol and some steryl esters inhibited the activity of L. giganteum phospholipase A2 (PLA2), an enzyme that hydrolyzes fatty acids from the sn-2 position of glycerophospholipids. Sterols that induce reproduction inhibited L. giganteum PLA2 activity, while sterols and steroids that do not support sporulation had minimal effect. Most steryl esters had no effect on enzyme activity, but cholesteryl arachidonate (CA) was a potent inhibitor of parasite PLA2. Not all enzymes partly purified using a DEAE-Sephacel column were affected by these lipids, demonstrating selective inhibition of specific enzymes. Potency was enhanced by up to several orders of magnitude if epoxy fatty acids were esterified to the cholesterol nucleus. The steryl ester pool was dynamic during morphogenesis, and the fatty acid composition of the steryl esters did not mimic total cell or membrane (glycerophospholipid) fatty acid composition as L. giganteum proceeded through its growth cycle. Synthesis of CA and monoepoxy CA by the parasite was confirmed using electrospray mass spectrometry and collision-induced dissociation. Steryl derivatives selectively inhibited PLA2 enzymes from bovine pancreas, snake venom, and human cytoplasmic 85-kDa PLA2. 相似文献
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Introduces this month's "Psychology in the Public Forum" section, which is devoted to alcoholism in the effort to spotlight contributions by psychologists to enhanced understanding of alcoholism and the alcoholic. They have been asked to contribute to this issue of the American Psychologist because their work has been influential in altering unhelpful views on alcoholism, offering a new and clearer picture of the determinants of alcoholism, or developing approaches to more efficacious therapeutic management of the alcoholic. All are activities in which the contributions of psychologists have been important. There are nine articles in this edition of "Psychology in the Public Forum." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The phylogenetic position of the phylum Porifera (sponges) is near the base of the kingdom Metazoa. During the last few years, not only rRNA sequences but, more importantly, cDNA/genes that code for proteins have been isolated and characterized from sponges, in particular from the marine demosponge Geodia cydonium. The analysis of the deduced amino acid sequences of these proteins allowed a molecular biological approach to the question of the monophyly of the Metazoa. Molecules of the extracellular matrix/basal lamina, with the integrin receptor, fibronectin, and galectin as prominent examples, and of cell-surface receptors (tyrosine kinase receptor), elements of sensory systems (crystallin, metabotropic glutamate receptor) as well as homologs/modules of an immune system (immunoglobulin-like molecules, scavenger receptor cysteine-rich [SRCR]- and short consensus repeats [SCR]-repeats), classify the Porifera as true Metazoa. As living fossils, provided with simple, primordial molecules allowing cell-cell and cell-matrix adhesion as well as processes of signal transduction as known in a more complex manner from higher Metazoa, sponges also show pecularities not known in later phyla. In this paper, the adhesion molecules presumably involved in the sponge immune system are reviewed; these are the basic adhesion molecules (galectin, integrin, fibronectin, and collagen) and especially the highly polymorphic adhesion molecules, the receptor tyrosine kinase as well as the polypeptides comprising scavenger receptor cysteine-rich (SRCR) and short consensus repeats (SCR) modules. In addition, it is reported that in the model sponge system of G. cydonium, allogeneic rejection involves an upregulation of phenylalanine hydroxylase, an enzyme initiating the pathway to melanin synthesis. 相似文献
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Presents statutory interpretations that are common in many boards of psychologist examiners. The article reflects the experience of both authors as past chairs of their respective states' Board of Psychologist Examiners and their firsthand experience with licensure procedures. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献