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排序方式: 共有2684条查询结果,搜索用时 31 毫秒
91.
Denis Bertin Pierre‐Emmanuel Dufils Isabelle Durand Didier Gigmes Bruno Giovanetti Yohann Guillaneuf Sylvain R. A. Marque Trang Phan Paul Tordo 《Macromolecular chemistry and physics.》2008,209(2):220-224
The effect of the penultimate unit on the C? ON bond homolysis rate constant kd was studied for model alkoxyamines. It was shown that the kd for fragments containing penultimate and antepenultimate units were nicely predicted by the tri‐parametric relationship developed in Macromolecules 2005 , 38, 2638 and Eur. J. Org. Chem. 2006 , 7, 1755 (log kd = ?14.33 + 15.06 × σRS + 20.00 × σI + 6.96 × υ). A striking effect was observed only for a tert‐butyl‐like group as the penultimate unit.
92.
Bart Rikhof Steven de Jong Albert JH Suurmeijer Coby Meijer Winette TA van der Graaf 《The Journal of pathology》2009,217(4):469-482
Sarcomas are a diverse group of malignant mesenchymal tumours arising from bone and soft tissues. The identification of critical cellular signalling pathways in sarcomas is an important issue for the development of new targeted therapies. This review highlights the experimental and clinical evidence supporting the role of the insulin‐like growth factor (IGF) signalling system in the cellular transformation and progression of several types of sarcoma, including rhabdomyosarcoma, synovial sarcoma, leiomyosarcoma, Ewing's sarcoma and osteosarcoma. Preclinical data suggest that the IGF system could be a promising target for therapy in these sarcomas. Currently, therapies interrupting IGF signalling have been or are being developed. In recent phase 1 clinical studies with humanized monoclonal antibodies directed against IGF receptor type 1 (IGF‐1R), objective tumour responses were observed in several patients with Ewing's sarcoma, encouraging further clinical testing in Ewing's sarcoma and other sarcoma (sub)types. Moreover, the occasional occurrence of paraneoplastic hypoglycaemia as a result of the secretion of incompletely processed forms of pro‐IGF‐II by sarcomas is discussed. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
93.
94.
T follicular regulatory (Tfr) cells are a subpopulation of Treg cells that have adopted the T follicular helper cell program to localize to the B‐cell follicle. Because of the difficulties in generating mouse models in which Tfr cells are selectively affected, determining where and how Tfr cells regulate the germinal center response remains to be resolved. In this issue of the European Journal of Immunology, Dent and colleagues [Eur. J. Immunol. 2016. 46: 1152–1161] describe a simple, elegant mouse model to conditionally delete Tfr cells without impacting on the Treg‐ and Tfh‐cell populations. Their initial studies suggest that Tfr cells have a more complex role than previously thought, particularly with respect to the regulation of immunoglobulin isotype switching to IgA. 相似文献
95.
Summary. A total of 517 fecal specimens collected from infants and children with acute gastroenteritis in Karachi city, Pakistan during 1990–1994 were examined for the presence of sapovirus by RT-PCR and sequence analysis methods. Sapovirus was identified in 17 of 517 (3.2%) specimens. Sapovirus was further clustered into three distinct genogroups (I, II and IV) and these presented 70.6%, 23.5% and 5.9%, respectively. Our results clearly indicated that sapovirus could be classified into 7 GI and 4 GII genotypes. It was noteworthy to point out that sapovirus detected among Pakistani infants and children with acute gastroenteritis demonstrated the great genetic diversity and presented novel sapovirus genotypes. 相似文献
96.
Role of Eotaxin-1 (CCL11) and CC chemokine receptor 3 (CCR3) in bleomycin-induced lung injury and fibrosis 下载免费PDF全文
Huaux F Gharaee-Kermani M Liu T Morel V McGarry B Ullenbruch M Kunkel SL Wang J Xing Z Phan SH 《The American journal of pathology》2005,167(6):1485-1496
Eotaxin-1/CCL11 and its receptor CCR3 are involved in recruitment of eosinophils to diverse tissues, but their role in eosinophil recruitment in pulmonary fibrosis is unclear. The present study examined the pulmonary expression of CCL11 and CCR3 during bleomycin (blm)-induced lung injury and determined their importance in the recruitment of inflammatory cells and the development of lung fibrosis. In mice, blm induced a marked pulmonary expression of CCL11 and CCR3. Immunostaining for CCR3 revealed that this receptor was not only expressed by eosinophils but also by neutrophils. CCL11-deficient (CCL11(-/-)) mice developed significantly reduced pulmonary fibrosis. Expression of profibrotic cytokines such as transforming growth factor-beta1 was diminished in the absence of CCL11. Furthermore, increased lung expression of CCL11 significantly enhanced blm-induced lung fibrosis and production of profibrotic cytokines. These effects were also associated with an increase of eosinophil and neutrophil pulmonary infiltration. In contrast, mice treated with neutralizing CCR3 antibodies developed significantly reduced pulmonary fibrosis, eosinophilia, neutrophilia, and expression of profibrotic cytokines. Together, these data suggest that CCL11 and CCR3 are important in the pulmonary recruitment of granulocytes and play significant pathogenic roles in blm-induced lung fibrosis. 相似文献
97.
松质骨中两种纵波的传播特性分析 总被引:2,自引:1,他引:2
基于松质骨的层状模型,利用Schoenberg理论分析了松质骨中两种纵波(快纵波和慢纵波)的传播特性;并在理论和实验上详细分析了骨小梁方向与传播方向间的夹角对松质骨中快纵波和慢纵波传播特性的影响。分析结果表明,当超声波平行于骨小梁入射时,松质骨中两种纵波都传播,入射角度在60度附近时,松质骨中两种纵波的相速度曲线有一个转折点,入射角度在60度以上,角度越大时,骨髓和骨小梁耦合得越紧,因此阻止了慢纵波的传播,而只有快纵波传播。 相似文献
98.
Shin JW Le VP Than VT Lim I Yoon Y Kim K Chung SI Myung SC Kim W 《Archives of virology》2012,157(4):753-759
The human rotavirus G9 strain is the fifth most common rotavirus worldwide. A human rotavirus G9P[8] strain CAU05-202 was
isolated from a young child with diarrhea using a cell culture system, and its major gene sequences were determined. Phylogenetic
analysis of the VP7 gene revealed that CAU05-202 clustered into genetic lineage III-d and was most closely related to G9 rotaviruses from Turkey
(strain GUH13) and Sri Lanka (strain 05SLC056 and 05SLC057). VP4 and NSP4 gene analysis showed that CAU05-202 belongs to the P[8]-3 lineage and genotype B, respectively. In addition, CAU05-202 has
a long RNA electropherotype, supported by VP6 gene analysis, which is clearly associated with subgroup II specificity. Analysis of the G9 rotavirus strain CAU05-202 provides
information concerning the genetic relationships among global rotavirus G9 strains, suggesting that closely related G9 strains
are persistent and widespread in Asian countries. 相似文献
99.
Evaluation of immunochromatography and commercial enzyme-linked immunosorbent assay for rapid detection of norovirus antigen in stool samples 总被引:1,自引:0,他引:1
Khamrin P Nguyen TA Phan TG Satou K Masuoka Y Okitsu S Maneekarn N Nishio O Ushijima H 《Journal of virological methods》2008,147(2):360-363
The efficiency of immunochromatography and commercial enzyme-linked immunosorbent assay (ELISA) kit (Denka Seiken Co. Ltd., Tokyo, Japan) were evaluated for rapid detection of norovirus (NoV) from stool specimens. A total of 503 stool specimens collected from infants and young children who suffered from acute gastroenteritis were tested for NoV by the NoV-immunochromatography kit, Denka ELISA kit, and by a monoplex RT-PCR method. The NoV-immunochromatography revealed 78.9% sensitivity, 96.4% specificity, and 92.4% efficiency with the monoplex RT-PCR method. The Denka ELISA kit had a sensitivity of 90.4%, specificity of 96.4%, and an efficiency level of 95%. The findings indicate that the newly developed NoV-immunochromatography kit provides the specificity equal to that of the Denka ELISA kit, even through the sensitivity of detection was lower. However, the advantage of the NoV-immunochromatography kit is less time consuming and simpler. The data show that both the Denka ELISA and the NoV-immunochromatography kits may be used as an alternative method for screening of NoV in stool samples. 相似文献
100.
Liu T Dhanasekaran SM Jin H Hu B Tomlins SA Chinnaiyan AM Phan SH 《The American journal of pathology》2004,164(4):1315-1326
Bleomycin-induced pulmonary fibrosis is characterized by inflammation, emergence of myofibroblasts, and deposition of extracellular matrix. In an attempt to identify genes that may be involved in fibrosis, we used a 10,000 element (10 K) rat cDNA microarray to analyze the lung gene expression profiles in this model in the rat. Cluster analysis showed 628 genes were more than or equal to twofold up- or down-regulated, many of which were known to be involved in fibrosis. However, the most dramatic increase was observed with FIZZ1 (found in inflammatory zone; also known as RELM-alpha or resistin-like molecule-alpha), which was induced 17-fold to approximately 25-fold at the peak of expression. In situ hybridization analysis revealed FIZZ1 expression to localize primarily to alveolar and airway epithelium, which was confirmed in vitro by analysis of isolated type II alveolar epithelial cells. However FIZZ1 expression was not detected in isolated lung fibroblasts. Co-culture of FIZZ1-expressing type II cells with fibroblasts stimulated alpha-smooth muscle actin and type I collagen expression independent of transforming growth factor-beta. Transfection of a FIZZ1-expressing plasmid into fibroblasts or treatment with glutathione S-transferase-FIZZ1 fusion protein stimulated alpha-smooth muscle actin and collagen I production. These results suggest a novel role for FIZZ1 in myofibroblast differentiation in pulmonary fibrosis. 相似文献