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991.
Christian Mathieu Valentina Moreno Patricio Retamal Alvaro Gonzalez Alejandro Rivera Jorge Fuller Cecilia Jara Claudio Lecocq Miriam Rojas Alfonso Garc��a Marcela Vasquez Michel Agredo Cristian Guti��rrez Hector Escobar Rodrigo Fasce Judith Mora Julio Garc��a Jorge Fern��ndez Claudio Ternicier Patricia Avalos 《Emerging infectious diseases》2010,16(4):709-711
Pandemic (H1N1) 2009 virus was detected in breeding turkeys on 2 farms in Valparaiso, Chile. Infection was associated with measurable declines in egg production and shell quality. Although the source of infection is not yet known, the outbreak was controlled, and the virus was eliminated from the birds. 相似文献
992.
993.
Beatrix Groneberg-Kloft Cristian Scutaru Q. Thai Dinh Tobias Welte K. Fan Chung Axel Fischer 《The Journal of asthma》2013,50(2):147-152
Background. The two obstructive airway diseases bronchial asthma and chronic obstructive pulmonary disease (COPD) represent major global causes of disability and death. Whereas COPD research was largely underfunded in the 1980s and 1990s, increased funding activities have been initiated since the year 2000. However, detailed scientometric data on the development of research for asthma and COPD have not been generated so far. Methods. The present scientometric study was conducted to establish a database of research quantity and quality in the 20-year period between 1987 and 2006 using the Web of Science information system and the United Kingdom and Germany for comparison of research activities. Results. The information database Web of Science was screened and during the period from 1987 to 2006 a number of 8,874 items related to asthma was published by UK affiliations. Of these, 1,824 were published in cooperation with a total of 86 other countries. This is a ratio of 20.55%. In the same period, 3,341 items were published by German institutions (923 in cooperation with 56 other countries, ratio of 27.63%). Citation analysis demonstrated an average citation of 24.48 per UK article and 17.62 per German article. For COPD, 2,179 items were published by UK affiliations and 689 items by German institutions. Of the UK COPD publications, 570 were published in cooperations with 47 countries (ratio of 22.95 %). By contrast, 218 of the 689 German COPD articles were published with 29 other countries (ratio of 25.49%). When citation analysis was performed, average citation ratios of 18.93 for the UK and 10.61 for German were found. Conclusion. Summarizing this first country-specific comparative benchmarking analysis for obstructive pulmonary diseases it can be concluded that () asthma research dominated in the past 20 years; () COPD research gained importance in the field since the end of the 1990s; () there are large differences present in the research output between the two high-income countries examined. 相似文献
994.
995.
Cristian Pérez Oscar G. Gómez-Duarte María L. Arias 《The American journal of tropical medicine and hygiene》2010,83(2):292-297
More than 5,000 diarrheal cases per year receive medical care at the National Children''s Hospital of Costa Rica, and nearly 5% of them require hospitalization. A total of 173 Escherichia coli strains isolated from children with diarrhea were characterized at the molecular, serologic, and phenotypic level. Multiplex and duplex polymerase chain reactions were used to detect the six categories of diarrheagenic E. coli. Thirty percent (n = 52) of the strains were positive, indicating a high prevalence among the pediatric population. Enteropathogenic E. coli and enteroinvasive E. coli pathotypes were the most prevalent (21% and 19%, respectively). Pathogenic strains were distributed among the four E. coli phylogenetic groups A, B1, B2, and D, with groups A and B1 the most commonly found. This study used molecular typing to evaluate the prevalence of diarrheagenic E. coli reported in Costa Rica and demonstrated the importance of these pathotypes in the pediatric population. 相似文献
996.
Sergi Gallego Cristian Neipp Luis A. Estepa Manuel Ortu?o Andrés Márquez Jorge Francés Inmaculada Pascual Augusto Beléndez 《Materials》2012,5(8):1373-1388
There is no doubt that the concept of volume holography has led to an incredibly great amount of scientific research and technological applications. One of these applications is the use of volume holograms as optical memories, and in particular, the use of a photosensitive medium like a photopolymeric material to record information in all its volume. In this work we analyze the applicability of Kogelnik’s Coupled Wave theory to the study of volume holograms recorded in photopolymers. Some of the theoretical models in the literature describing the mechanism of hologram formation in photopolymer materials use Kogelnik’s theory to analyze the gratings recorded in photopolymeric materials. If Kogelnik’s theory cannot be applied is necessary to use a more general Coupled Wave theory (CW) or the Rigorous Coupled Wave theory (RCW). The RCW does not incorporate any approximation and thus, since it is rigorous, permits judging the accurateness of the approximations included in Kogelnik’s and CW theories. In this article, a comparison between the predictions of the three theories for phase transmission diffraction gratings is carried out. We have demonstrated the agreement in the prediction of CW and RCW and the validity of Kogelnik’s theory only for gratings with spatial frequencies higher than 500 lines/mm for the usual values of the refractive index modulations obtained in photopolymers. 相似文献
997.
Valentina Bertaglia Marcello Tucci Cristian Fiori Emiliano Aroasio Massimiliano Poggio Consuelo Buttigliero Susanna Grande Andrea Saini Francesco Porpiglia Alfredo Berruti 《Clinical genitourinary cancer》2013,11(3):325-330.e1
BackgroundControversy exists about whether testosterone serum levels at a cutoff point of < 50 ng/dL during luteinizing hormone–releasing hormone analogue (LHRHA) treatment are related to the outcome of patients with prostate cancer. We assessed the relationship between serum testosterone levels after 6 months of LHRHA therapy and disease outcome in a consecutive series of patients with prostate cancer.Patients and MethodsSerum testosterone levels were measured prospectively in a cohort of patients given LHRHA for 6 months. End points were time to progression (TTP) and overall survival (OS).ResultsThe study population was 153 patients: 54 with metastatic disease and 99 with biochemical failure. In multivariate analysis, adjustment for age, baseline serum prostatic specific antigen (PSA) levels, Gleason score, and disease stage, testosterone levels < 50 ng/dL failed to be associated with TTP and OS. A cutoff of < 20 ng/dL was associated with a nonsignificant lower risk of progression (adjusted hazard ratio [HR] 0.58; 95% confidence interval [CI] 0.30-1.15; P = .12) and a significant lower risk of death (adjusted HR, 0.19; 95% CI, 0.04-0.76; P = .02). Only 25 patients attained serum testosterone levels < 20 ng/dL. Using a receiver operating characteristic curve (ROC), we found that a testosterone value of 30 ng/dL offered the best overall sensitivity and specificity for prediction of death. Serum testosterone levels < 30 ng/mL were associated with a significantly lower risk of death (adjusted HR, 0.45; 95% CI, 0.22-0.94; P = .034.ConclusionsSerum testosterone levels lower than the currently adopted cutoff of 50 ng/dL have a prognostic role in patients with prostate cancer receiving LHRHA and are a promising surrogate parameter of LHRHA efficacy. 相似文献
998.
999.
Elsa Curtit Virginie Nerich Laura Mansi Loic Chaigneau Laurent Cals Cristian Villanueva Fernando Bazan Philippe Montcuquet Nathalie Meneveau Sophie Perrin Marie‐Paule Algros Xavier Pivot 《The oncologist》2013,18(6):667-674