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排序方式: 共有1452条查询结果,搜索用时 15 毫秒
31.
MG Seves MJ Brito S Lamy PV Luiz G Bastos M Faleiro J Batista JF De Sousa 《Canadian Metallurgical Quarterly》1998,11(7):631-634
Hormone-refractory prostate cancer (HRPC) patients often have nonmeasurable disease. In such patients, predictive biomarkers other than tumor response may be required to compare therapeutic effects. We examined the predictive value for survival of various clinical and laboratory parameters, including prostate-specific antigen (PSA), in HRPC patients treated with suramin. Data from 103 HRPC patients were analyzed using various survival analyses, the likelihood ratio approach, and logistic regression analyses. When pretreatment factors, percentage decrease in PSA at 4 weeks from start of treatment (deltaPSA), and updated survival data were fit by a multivariate Cox proportional hazards model, acid phosphatase, lactate dehydrogenase, and deltaPSA were significant, with risk ratios close to 1. There was a decrease in likelihood ratio with increasing APSA. A logistic regression model was developed to predict the probability of <1 year of survival from the start of treatment. Hemoglobin and deltaPSA were found to be significant variables. However, in view of the complexities involving the relationship between PSA expression and prostate cancer growth and possible selective effect of treatment on PSA, further prospective testing is necessary. Therefore, deltaPSA cannot necessarily be used as a biomarker for survival response in individual patients during the evaluation of the therapeutic response of HRPC to new antineoplastic drugs. 相似文献
32.
AIM: To examine the association of Epstein-Barr virus (EBV) with carcinoma of the ear. METHODS: Five non-keratinising squamous cell carcinomas and two undifferentiated carcinomas of the ear were examined. In situ hybridisation was used to localised EBV-encoded RNAs (EBER). Immunohistochemical methods to detect LMP-1 and EBNA2 were performed in the EBER positive cases. RESULTS: Two cases were EBER positive, including one non-keratinising and one undifferentiated carcinoma. Both showed identical morphology to those arising from the nasopharynx, with abundant lymphoid stroma. They were both negative for LMP-1 and EBNA2. CONCLUSIONS: EBV associated carcinoma with the morphology of lymphoepithelioma can also arise from the middle ear. 相似文献
33.
Hantae Jo Sofia Brito Byeong Mun Kwak Sangkyu Park Mi-Gi Lee Bum-Ho Bin 《International journal of molecular sciences》2021,22(5)
Mesenchymal stem cells (MSCs) are multipotent stem cells derived from adult stem cells. Primary MSCs can be obtained from diverse sources, including bone marrow, adipose tissue, and umbilical cord blood. Recently, MSCs have been recognized as therapeutic agents for skin regeneration and rejuvenation. The skin can be damaged by wounds, caused by cutting or breaking of the tissue, and burns. Moreover, skin aging is a process that occurs naturally but can be worsened by environmental pollution, exposure to ultraviolet radiation, alcohol consumption, tobacco use, and undernourishment. MSCs have healing capacities that can be applied in damaged and aged skin. In skin regeneration, MSCs increase cell proliferation and neovascularization, and decrease inflammation in skin injury lesions. In skin rejuvenation, MSCs lead to production of collagen and elastic fibers, inhibition of metalloproteinase activation, and promote protection from ultraviolet radiation-induced senescence. In this review, we focus on how MSCs and MSC-derived molecules improve diseased and aged skin. Additionally, we emphasize that induced pluripotent stem cell (iPSC)-derived MSCs are potentially advanced MSCs, which are suitable for cell therapy. 相似文献
34.
Masaki Yasuoka Kiyoshi Hirao Manuel E. Brito Shuzo Kanzaki 《Journal of the American Ceramic Society》1995,78(7):1853-1856
Control of microstructure in the Al2 O3 /LaAl11 O18 system was performed. Elongated alumina grains were formed by doping with small addition of silica, and 20 vol% lanthana- luminate was formed in situ by the reaction of LaAlO3 - A12 O3 in an alumina matrix. Strengths of over 600 MPa and a high fracture toughness (6 MPa.m1/2 ) were achieved in the material with both elongated A12 O3 grains and LaAl11 O18 platelets. Generally antagonistic properties such as strength and fracture toughness have been made compatible in the same ceramic system. 相似文献
35.
Kiyoshi Hirao Masayoshi Ohashi Manuel E. Brito Shuzo Kanzaki 《Journal of the American Ceramic Society》1995,78(6):1687-1690
Silicon nitride with a preferred orientation of large elongated grains was obtained by tape casting of raw powder slurry seeded with rodlike β-Si3 N4 particles, followed by a gas pressure sintering under 1 MPa nitrogen pressure. The large elongated grains developed from seeds lay in planes parallel to the casting direction in a two-dimensional distribution. Increased fracture toughness (11.1 MPa·m1/2 ) and bending strength (1100 MPa) were achieved in the direction perpendicular to the grains alignment compared to specimens with a random distribution of elongated grains. Morover, the specimens exhibited a high Weibull modulus of 46 due to the uniform distribution of large grains. 相似文献
36.
Rgia Maria Cordeiro Brito Alzir Azevedo Batista Javier Ellena Eduardo E. Castellano Izaura Cirino Nogueira Digenes Luiz Gonzaga de Frana Lopes Jackson Rodrigues de Sousa Ícaro de Sousa Moreira 《Inorganic chemistry communications》2007,10(12):1515-1517
The cis-[Ru(dppb)(Me-bipy)(NCS)2], dppb = 1,4-bis (diphenylphosphino)butane, Me-bipy = 4,4′-dimethyl-2,2′-bipyridine, and NCS = thiocyanate, was synthesized and characterized by spectroscopic and electrochemical techniques and its structure was determined by crystal X-ray analysis. The crystal structure reveals that the coordination geometry around the Ru(II) center is distorted octahedron where two molecules of thiocyanate are bonded to the ruthenium through nitrogen atom in cis orientation. The half-wave formal potential value E1/2 = 0.8 V (versus Ag/AgCl) observed is considerable higher than that for the cis-[RuCl2(dppb)(Me-bipy)] complex, E1/2 = 0.6 V (versus Ag/AgCl), well illustrating the strong π-acceptor effect the NCS ligand toward the backbonding interaction with the Ru(II) metal center. The MLCT absorption bands of the thiocyanate complex present a higher molar absorptivity (about 12%) compared with the cis-[RuCl2(dppb)(Me-bipy)] complex, in the same experimental conditions. These properties make the complex potentially promising for the photosensitization process. 相似文献
37.
Brito Ricardo Biuk-Aghai Robert P. Fong Simon 《Multimedia Tools and Applications》2021,80(8):12293-12308
Multimedia Tools and Applications - In this paper, we propose a new method for improving human activity recognition (HAR) datasets in order to increase their classification accuracy when trained... 相似文献
38.
扫描笔是近年新兴的扫描产品,它又可以称为微型扫描仪或手刮式扫描笔,常见的扫描笔大小大约跟"折扇"差不多,甚者会更小。它最大的特点是携带方便,特别适合商务人士随身携带出差办公使用。一般购买它主要是用于扫描办公文件、身份证、名片或大型工程图等等。下面,小编带大家去深入了解扫描笔,让你能够知才善用。 相似文献
39.
Shepperd Martin Abreu Fernando Brito e Perez-Castillo Ricardo 《Software Quality Journal》2022,30(2):281-282
Software Quality Journal - 相似文献
40.