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排序方式: 共有2736条查询结果,搜索用时 15 毫秒
951.
Débora P. Paula David A. Andow André Bellinati Renata Velozo Timbó Lucas M. Souza Carmen S. S. Pires Edison R. Sujii 《Ecotoxicology (London, England)》2016,25(3):601-607
Dose–response assays and surrogate species are standard methods for risk analysis for environmental chemicals. These assume that individuals within a species have unimodal responses and that a surrogate species can predict responses of other related taxa. We exposed immature individuals of closely related aphidophagous coccinellid predators, Cycloneda sanguinea and Harmonia axyridis, to Cry1Ac and Cry1F toxins through uniform and constant artificial tritrophic exposure through Myzus persicae aphids. Both toxins were detected in coccinellid pupae, with individual and interspecific variation. Uptake was significantly higher in H. axyridis than in C. sanguinea, both in the proportion of individuals and the concentrations per individual. We also observed bimodal uptake of the Cry toxins by H. axyridis, which indicated that some individuals had low bioaccumulation and some had high bioaccumulation. This suggests that standard dose–response assays need to be interpreted with caution and future assays should examine the modality of the responses. In addition, the similarity in the biological effects of the Cry toxins in the two predators was due to different biological exposure mechanisms. The majority of H. axyridis were exposed both internally and in the gut, while C. sanguinea was exposed primarily in the gut. Thus, despite their close phylogenetic relatedness, these species would not be good surrogates for each other and the surrogate species methodology should be tested more rigorously. 相似文献
952.
Pires de Morais G Bettencourt N Silva G Ferreira N Sousa O Caeiro D Rocha J Carvalho M Leite D Braga P Fonseca C Gama V 《Revista portuguesa de cardiologia》2011,30(9):717-726
Transcatheter aortic valve implantation is an emerging treatment option for severe symptomatic aortic stenosis in patients considered unsuitable for surgical valve replacement. The authors review the use of multislice computed tomography in the selection of candidates for transcatheter aortic valve replacement, procedural support and post-interventional follow-up. A single-center experience of the role of this imaging technique is also described. Multislice computed tomography is an essential imaging tool in the selection and exclusion of candidates for transcatheter aortic valve implantation, providing evaluation of coronary anatomy and the relationship of the coronary ostia with the aortic valve structure, and accurate analysis of the valve annulus and aortic root, left ventricular outflow tract, aorta and peripheral vascular access routes. Multislice computed tomography is also central to the choice of appropriate prosthesis size. In addition, it guides arterial puncture by image fusion techniques and enables correct prosthesis apposition to be verified. This review aims to describe the role of computed tomography in this increasingly common interventional valve procedure, providing an overview of current knowledge and applications. 相似文献
953.
Cordinh? C Pereira ? Silva PV Dionísio T Martins P Sousa G Santos I Pires A Ribeiro L Castela E 《Revista portuguesa de cardiologia》2011,30(10):795-797
Cardiac tumors in the pediatric population are rare, their incidence range between 0.001% and 0.003%. They are mostly benign, rhabdomyomas the most common type, followed by fibromas. The clinical features are being usually nonspecific and depend on the size and location of the tumor within the heart. We report the case of a previously healthy four-year-old boy referred for flu-like symptoms. A respiratory infection was suspected and a chest X-ray showed an increased cardiothoracic index. An echocardiogram revealed a single large heterogeneous mass in the left ventricle emerging from the lateral wall. Despite its size, the mass did not obstruct the left ventricular outflow tract or affect mitral valve function. Cardiac magnetic resonance imaging showed a large mass whose imaging features were suggestive of a fibroma. He became symptomatic during follow-up and was referred for surgical excision of the mass. Histological study confirmed a fibroma. At present the patient remains asymptomatic. 相似文献
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Mattar A Logullo AF Facina G Nonogaki S Soares FA Gebrim LH 《Journal of cancer research and clinical oncology》2011,137(5):897-905
Purpose
The objective of this study was to compare Ki-67, Bcl-2, Bax, Bak, ER, and PgR expression in postmenopausal women with ER-positive invasive breast cancer (IBC) before and after short-term hormone therapy (HT) with either tamoxifen or anastrozole in order to identify a possible biomarker profile associated with hormone resistance. 相似文献957.
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Suelen Gonçalves Rabelo Camila França Teixeira Mariana Pires C. Telles Rosane G. Collevatti 《Conservation Genetics Resources》2011,3(4):741-743
Lychnophora ericoides is an endangered species, endemic to cerrado rupestre. Herein we report the development and characterization of 13 polymorphic microsatellite loci for the species, using enriched genomic library. Number of alleles per locus and expected heterozygosity ranged from 06 to 13 and 0.696 to 0.894, respectively. The high combined probability of genetic identity (2.69 × 10?17) and probability of paternity exclusion (0.9999) showed that multilocus genotypes are likely to be unique and will allow detailed parentage studies in natural populations of L. ericoides. 相似文献
960.
Izabela Guimarães Barbosa Rodrigo Barreto Huguet Vanessa Amaral Mendonça Lirlândia Pires Sousa Fernando Silva Neves Moisés Evandro Bauer Antônio Lúcio Teixeira 《European archives of psychiatry and clinical neuroscience》2011,261(2):139-143
Bipolar disorder (BD) has been associated with a proinflammatory state in which TNF-α seems to play a relevant role. The aim
of the present study was to evaluate the plasma levels of TNF-α and its soluble receptors (sTNFR1 and sTNFR2) in BD patients
in mania and euthymia in comparison with control subjects. We evaluated 53 BD patients (34 in mania and 19 in euthymia) and
38 healthy subjects. All subjects were assessed by the Mini-International Neuropsychiatry Interview (MINI-Plus). Patients
were also evaluated by the Young Mania Rating Scale (YMRS) and by Hamilton Depression Rating Scale (HDRS). Plasma TNF-α and
its soluble receptors were measured by ELISA. The plasma TNF-α and sTNFR2 levels did not differ between groups, but higher
sTNFR1 levels were found in BD patients. Of note, BD patients in mania had higher sTNFR1 levels than BD patients in euthymia
and controls. The sTNFR1 and sTNFR2 levels correlated with BD duration, and sTNFR2 levels correlated with age of patients.
Our data indicate a proinflammatory status in BD patients during mania and further suggest that inflammatory mechanisms may
be involved with the physiopathology of BD. 相似文献