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21.
零件的批处理和零件库的建立是计算机辅助设计的重要内容之一,以钢管相贯口为例应用UG的几种建库方法,通过分析电子表格、零件族、GRIP编程在变参变结构的复杂零件建库时存在的问题,提出了一种将零件族和GRIP编程相结合的建库方法来建立变参变结构的复杂零件的零件库。  相似文献   
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Riassunto Proseguendo precedenti ricerche si mette in evidenza che esiste una correlazione anche tra trasporto di sodio e trasporto di vari amino acidi attraverso l'intestino tenue isolato di ratto albino. Se ne deduce che presumibilmente ogni sostanza capace di essere trasportata attivamente stimola il trasporto di sodio e che quest'ultima funzione diventa solo un indice dell'attività totale di trasporto dell'epitelio intestinale.

This work has been supported by a research grant of the Consiglio Nazionale delle Ricerche, Roma.  相似文献   
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Riassunto L'introduzione nella cavità midollare dello sterno di soggetti affetti da morbo di Cooley di ARN II° estratto dalle cellule emopoiteiche normali, provoca un netto aumento della quota di HbA nelle cellule della serie eritroblastica.  相似文献   
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Auto-antibodies to the ubiquitous enzyme type-2 transglutaminase (TG2) are a specific hallmark of celiac disease (CD), a widely diffused, multi-factorial disease, affecting genetically predisposed subjects. In CD an inflammatory response, at the intestinal level, is triggered by diet consumption of gluten-containing cereals. Intestinal mucosa displays various degrees of atrophy and hyperplasia, with consequent global intestinal dysfunction and other relevant extra-intestinal symptoms. Through deamidation of specific glutamines of gluten-derived gliadin peptides, TG2 strongly enhances gliadin immunogenicity. In addition, TG2 cross-linking activity may generate complexes between TG2 itself and gliadin peptides, and these complexes seem to cause the auto-immune response by means of an apten-carrier-like mechanism of antigen presentation. Anti-TG2 antibodies can be early detected in the intestinal mucosa of celiac patients and are also abundantly present into the serum, thus potentially reaching other organs and tissues by blood circulation. Recently, the possible pathogenetic role of auto-antibodies to TG2 in CD has been investigated. Here, we report an overview about the genesis of these antibodies, their specificity, their modulating ability toward TG2 enzymatic or non-enzymatic activities and their biological effects exerted by interacting with extracellular TG2 or with cell-surface TG2. We also discuss the auto-immune response occurring in CD against other TG members (i.e. type 3 and type 6) and analyze the occurrence of anti-TG2 antibodies in other auto-immune CD-related diseases. Data now available let us to suppose that, even if antibodies to TG2 do not represent the triggering molecules in CD, they could be important players in disease progression and manifestations.  相似文献   
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Extending previous risk model backtesting literature, we construct multiple hypothesis testing (MHT) with the stationary bootstrap. We conduct multiple tests which control for the generalized confidence level and employ the bootstrap MHT to design multiple comparison testing. We consider absolute and relative predictive ability to test a range of competing risk models, focusing on value‐at‐risk and expected shortfall (ExS). In devising the test for the absolute predictive ability, we take the route of recent literature and construct balanced simultaneous confidence sets that control for the generalized family‐wise error rate, which is the joint probability of rejecting true hypotheses. We implement a step‐down method which increases the power of the MHT in isolating false discoveries. In testing for the ExS model predictive ability, we design a new simple test to draw inference about recursive model forecasting capability. In the second suite of statistical testing, we develop a novel device for measuring the relative predictive ability in the bootstrap MHT framework. The device, which we coin multiple comparison mapping, provides a statistically robust instrument designed to answer the question: ‘Which model is the best model?’ Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Riassunto Vengono descritte le modificazioni morfologiche, rilevate al microscopio elettronico, delle cellule reticolari leucemiche coltivate in presenza di ARN estratto dalla milza di embrioni di vitello.  相似文献   
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Zusammenfassung Der Einfluss des Natriums auf die passive Permeabilität der Jejunum-Schleimhaut der Laboratoriumsratte gegenüber wasserlöslichen, nichtmetabolisierbaren und elektroneutralen Substanzen (Thioharnstoff, Azetamid) wurde untersucht. Wird das Natrium des NaCl in der Perfusionsflüssigkeit durch Trisoder Cholin-Kationen ersetzt, so nehmen sowohl der transepitheliale Glukosetransport wie auch die Mobilität der geprüften Substanzen ab.

This work has been supported by a research grant of the Consiglio Nazionale delle Ricerche, Roma. The authors acknowledge, with warm appreciation, the valuable technical assistance of Mr. R.Parotelli.  相似文献   
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