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51.
EA Scodeller SG Tisminetzky F Porro M Schiappacassi A De Rossi L Chiecco-Bianchi FE Baralle 《Canadian Metallurgical Quarterly》1995,13(13):1233-1239
The principal neutralizing domain, IGPGRAF sequence, from the V3-loop of HIV-1 was inserted in two positions on the surface of the protein that makes up the capside shell of the insect Flock House Virus. The hybrid proteins were expressed in insect cells via recombinant baculoviruses. Three different hybrids were used as immunogens: two with a single copy of the insert in different positions of the carrier protein and a third with two copies of the insert at the same positions as before. All hybrid proteins induced strong and broad specific immune response in guinea pigs against different V3-loop sequences. However, only one of the hybrid proteins was able to induce a strong neutralizing response against MN and IIIB HIV-1 isolates. Our results demonstrate that a very short peptide sequence of HIV-1 can constitute a valuable immunogen able to induce a neutralizing response if presented to the immune system in the context of the FHV capsomer structure. 相似文献
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53.
As the antibiotic arsenal expands with the development of new oral agents, selecting appropriate therapy is becoming more difficult. What are the therapeutic indications for the newer antimicrobials, and what advantages do they have over traditional agents? Drs Gleckman and De La Rosa discuss current issues related to antibiotic treatment and offer specific recommendations for the best use of the newer agents. 相似文献
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55.
D Brodaty G Dreyfus C Dubois P De Lentdecker C Barbagelatta PF Bouchet LJ Couderc O Bletry P Honderlick D Guilmet 《Canadian Metallurgical Quarterly》1998,91(12):1525-1529
The authors report a case of giant cell myocarditis leading to rapidly progressive cardiac failure despite immuno-suppressor treatment in a 20 year old woman. The cardiac failure was successfully managed by implantation of a left ventricular assist device and then cardiac transplantation. The problems encountered underline the importance of accurate diagnosis by endomyocardial biopsy before undertaking treatment and the difficulties in the choice of appropriate method of assistance in this indication. Giant cell myocarditis is a rare cause of cardiac failure and should be considered in the differential diagnosis in view of its clinical features and risk of progression. The literature and the therapeutic implications are discussed. 相似文献
56.
Cordella L.P. De Stefano C. Tortorella F. Vento M. 《Neural Networks, IEEE Transactions on》1995,6(5):1140-1147
Criteria for evaluating the classification reliability of a neural classifier and for accordingly making a reject option are proposed. Such an option, implemented by means of two rules which can be applied independently of topology, size, and training algorithms of the neural classifier, allows one to improve the classification reliability. It is assumed that a performance function P is defined which, taking into account the requirements of the particular application, evaluates the quality of the classification in terms of recognition, misclassification, and reject rates. Under this assumption the optimal reject threshold value, determining the best trade-off between reject rate and misclassification rate, is the one for which the function P reaches its absolute maximum. No constraints are imposed on the form of P, but the ones necessary in order that P actually measures the quality of the classification process. The reject threshold is evaluated on the basis of some statistical distributions characterizing the behavior of the classifier when operating without reject option; these distributions are computed once the training phase of the net has been completed. The method has been tested with a neural classifier devised for handprinted and multifont printed characters, by using a database of about 300000 samples. Experimental results are discussed. 相似文献
57.
The influence of fibrin glue on adhesion formation and peritoneal healing is evaluated in a prospective, randomized, controlled study. In all, 20 Wistar rats underwent microsurgical suturing of two silicone sheets, one covered with a fibrin glue barrier, to the anterior peritoneum. Each animal thus served as its own control. After 10 days, adhesions and peritoneal healing were evaluated by a blinded observer through a second-look laparotomy. Adhesions were scored using a modification of the classification of Diamond. Tissue around the silicone sheet was examined histologically and by scanning electron microscopy to evaluate the inflammatory reaction and peritoneal healing (ingrowth of blood vessels and quality of peritoneal cells). Adhesion scores for treated and control sides were (mean +/- SD) 2.89 +/- 4.68 and 6.79 +/- 9.09 (P = 0.181) respectively, and the percentage of the sheet covered by peritoneum was 26.25 +/- 31.50 and 29.21 +/- 40.21 (P = 0.226) respectively. Using the paired Wilcoxon rank test, the P values for the ingrowth of blood vessels and peritoneal healing evaluated by histology and scanning electron microscopy were 0.842, 0.692 and 0.695 respectively. We conclude that although the mean adhesion score was reduced by > 50% by fibrin glue, there is no statistically significant difference concerning adhesion formation or peritoneal healing with the use of fibrin glue. 相似文献
58.
Marie-Angele De Looze R. Coronini Monique Legentil P. Jeannin Marie-Hélene Magri 《Scientometrics》1996,36(2):167-183
This paper analyses the determination of visibility of journals in which researchers of INRA (National Institute for Agricultural Research) publish. The corpus is comprised of 671 articles published over a period of four years in 258 journals. The advantage of the method applied for determining the visibility of journals is that it combines two approaches: a) bibliometric indicators (coverage by the ISI-publications and by two specific French databases) and b) experts' opinions (10 economists and sociologists). The main results are: a) There is a convergence between the opinion of the experts and «visibility» in the databases, b) The impact factor confirms the main opinions of the experts. The first journals ranked by the experts and JCR Social Sciences are the same but represent only 40 per cent of the total journals analysed. The other journals were revealed by the experts and French databases.«Whoever seeks to pass a balanced but lucid judgement on the general trends of the activity carried out by the profession to which he belongs, is liable to say either banalities or to hurt his colleagues»The notion which we retain of core is that which is successively and conjointly validated by the experts and by the major databases representative of the field.This study was financed by the Department of Rural Economy and Sociology of INRA. 相似文献
59.
Arpaia P. Avallone F. Baccigalupi A. De Capua C. 《IEEE transactions on instrumentation and measurement》1996,45(2):462-466
Two real-time algorithms for active power measurements on Pulse Width Modulation (PWM) electric drives are proposed. The former is an off-line algorithm reducing truncation error through an accurate signal period estimation and a proper window. The second is an on-line algorithm based on a low-pass IIR digital filter with an optimized transient phase. Numerical results of the metrological characterization of such algorithms, aimed to suggest criteria for their use, are presented. The experimental results of tests carried out on an actual drive confirm numerical simulations and are in perfect agreement with those of a well-acclaimed algorithm 相似文献
60.