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排序方式: 共有371条查询结果,搜索用时 15 毫秒
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Giovanni Faggioni PhD Riccardo De Santis PhD Alice Pomponi PhD Antonella Grottola LS Giulia Fregni Serpini LS Marisa Meacci LS William Gennari LS Sara Tagliazucchi LS Monica Pecorari LS Federica Monaco LS Giovanni Savini PhD Eleonora Benedetti LS Maria Elena Remoli LS Claudia Fortuna LS Giulietta Venturi LS Giovanni Rezza MD Florigio Lista MD 《Journal of medical virology》2018,90(10):1666-1668
A collection of 3069 human sera collected in the area of the municipality of Modena, Emilia Romagna, Italy, was retrospectively investigated for specific antibodies against Usutu (USUV) and West Nile viruses (WNV). All the samples resulting positive using a preliminary screening test were analyzed with the plaque reduction neutralization test. Overall, 24 sera were confirmed as positive for USUV (0.78%) and 13 for WNV (0.42%). The results suggest that in 2012, USUV was circulating more than WNV in North‐eastern Italy. 相似文献
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Ways DK; Qin W; Riddle RS; Garris TD; Bennett TE; Steelman LS; McCubrey JA 《Blood》1991,78(10):2633-2641
FD/PMA is a subclone of the interleukin-3 (IL-3)-dependent, FDC-P1 cell line, which proliferates in response to either 12-O- tetradecanoylphorbol-13 acetate (PMA) or IL-3. While several endogenous substrates were phosphorylated in response to protein kinase C (PKC) activation in FDC-P1, phospholipid-dependent phosphorylation in the FD/PMA grown in PMA was not observed. Basal, phosphatidylserine- independent, and diolein-independent phosphorylation of cytosolic substrates with molecular weights of 17, 52, 57, and 105 Kd were enhanced in FD/PMA cells grown in PMA as compared with FDC-P1 cells cultured in IL-3. Phosphorylation of a 105-Kd substrate was enhanced in the particulate fraction of FD/PMA cells maintained in PMA. The 17-Kd substrate in FD/PMA cells comigrated with a substrate phosphorylated in a PKC-dependent manner in FDC-P1 cells. Phosphorylation of the 52- and 57-Kd substrates, but not of the 17-Kd substrate, was inhibited by H-7 and staurosporine. A portion of the PMA-induced cytosolic kinase activity coeluted with PKC on diethyl aminoethyl chromatography. While FD/PMA cells cultured in PMA contained negligible PKC-dependent phosphorylation of endogenous substrates or histone, alpha and epsilon PKC isoforms were detected by Western blot analysis. PKC phosphotransferase activity was observed in FD/PMA cells grown in PMA when peptides corresponding to residues 720 to 737 of PKC-epsilon or residues 4 to 14 of myelin basic protein were used as substrates. These data indicate that maintenance of FD/PMA cells in PMA stimulates proliferation and markedly alters PKC substrate specificity. Generation of at least two phospholipid-independent kinases occurs in PMA-treated cells. 相似文献
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Negative charge distribution and density on the surface of oxygenated normal and sickle red cells 总被引:2,自引:0,他引:2
Negative charges on the external surface of red cells were visualized by colloidal iron hydroxide labelling of 50% of the membrane area after osmotic hemolysis and glutaraldehyde fixation. Counts were made over randomly selected areas on electron micrographs at 350,000 x magnification. Statistical analyses showed that at the 95% level of confidence there was no significant difference between oxygenated normal (AA) and sickle (SS) cells in either the distribution or the density of negative charges. 相似文献
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Health practitioners work under fiduciary constraint, and are obligated to favour patient needs over all others and in particular their own. The principles of professionalism demand that professionals take great care to ensure that boundaries are maintained safely to provide an optimal setting in facilitating patient care. Boundary violations cause serious harm to the patient. Any romantic or sexual activity between parties is the most serious form of boundary violation. The chiropractic profession is included in the list of disciplines which are at an increased risk for boundary violations. The authors propose a four stage protocol which is designed to offer all parties maximal protection beginning with undergraduate professional education and then mandatory continuing education for registrants in professional practice. The protocol would affect all aspects of professional life including training in boundaries and jurisdictional regulation. 相似文献
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Erythropoietin structure-function relationships: high degree of sequence homology among mammals 总被引:7,自引:3,他引:4
Wen D; Boissel JP; Tracy TE; Gruninger RH; Mulcahy LS; Czelusniak J; Goodman M; Bunn HF 《Blood》1993,82(5):1507-1516
To investigate structure-function relationships of erythropoietin (Epo), we have obtained cDNA sequences that encode the mature Epo protein of a variety of mammals. A first set of primers, corresponding to conserved nucleotide sequences between mouse and human DNAs, allowed us to amplify by polymerase chain reaction (PCR) intron 1/exon 2 fragments from genomic DNA of the hamster, cat, lion, dog, horse, sheep, dolphin, and pig. Sequencing of these fragments permitted the design of a second generation of species-specific primers. RNA was prepared from anemic kidneys and reverse-transcribed. Using our battery of species-specific 5' primers, we were able to successfully PCR- amplify Epo cDNA from Rhesus monkey, rat, sheep, dog, cat, and pig. Deduced amino acid sequences of mature Epo proteins from these animals, in combination with known sequences for human, Cynomolgus monkey, and mouse, showed a high degree of homology, which explains the biologic and immunological cross-reactivity that has been observed in a number of species. Human Epo is 91% identical to monkey Epo, 85% to cat and dog Epo, and 80% to 82% to pig, sheep, mouse, and rat Epos. There was full conservation of (1) the disulfide bridge linking the NH2 and COOH termini; (2) N-glycosylation sites; and (3) predicted amphipathic alpha- helices. In contrast, the short disulfide bridge (C29/C33 in humans) is not invariant. Cys33 was replaced by a Pro in rodents. Most of the amino acid replacements were conservative. The C-terminal part of the loop between the C and D helices showed the most variation, with several amino acid substitutions, deletions, and/or insertions. Calculations of maximum parsimony for intron 1/exon 2 sequences as well as coding sequences enabled the construction of cladograms that are in good agreement with known phylogenetic relationships. 相似文献
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