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排序方式: 共有356条查询结果,搜索用时 390 毫秒
71.
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Keita Kamijo Naiman A. Khan Matthew B. Pontifex Mark R. Scudder Eric S. Drollette Lauren B. Raine Ellen M. Evans Darla M. Castelli Charles H. Hillman 《Obesity (Silver Spring, Md.)》2012,20(12):2406-2411
Adiposity may be negatively associated with cognitive function in children. However, the findings remain controversial, in part due to the multifaceted nature of cognition and perhaps the lack of accurate assessment of adiposity. The aim of this study was to clarify the relation of weight status to cognition in preadolescent children using a comprehensive assessment of cognitive control, academic achievement, and measures of adiposity. Preadolescent children between 7 and 9 years (n = 126) completed Go and NoGo tasks, as well as the Wide Range Achievement Test 3rd edition (WRAT3), which measures achievement in reading, spelling, and arithmetic. In addition to BMI, fat mass was measured using dual‐energy X‐ray absorptiometry (DXA). Data were analyzed with multiple regression analysis, controlling for confounding variables. Analyses revealed that BMI and fat mass measured via DXA were negatively associated with cognitive control, as children with higher BMI and fat mass exhibited poorer performance on the NoGo task requiring extensive amounts of inhibitory control. By contrast, no relation of weight status to performance was observed for the Go task requiring smaller amounts of cognitive control. Higher BMI and fat mass were also associated with lower academic achievement scores assessed on the WRAT3. These data suggest that adiposity is negatively and selectively associated with cognitive control in preadolescent children. Given that cognitive control has been implicated in academic achievement, the present study provides an empirical basis for the negative relationship between adiposity and scholastic performance. 相似文献
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M Sensi M Bergomi P Panceri C Castelli R Lupetti C Traversari G Carbone G Parmiani 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(1):277-283
Immunogenic tumor variants were previously derived after transplantation in vivo into nude mice of NIH/3T3-transformed cell lines. Nude-passaged cell lines were rejected by immunocompetent H-2q NIH mice, were recognized by specific CTL clones, and expressed new retroviral Ag. The aim of the present work was to investigate whether somatically acquired proviral sequences were present in the genome of nude-passaged cells and to test directly for a causative relationship between murine leukemia virus (MuLV) expression and immunogenicity. Southern blot analysis of PstI-digested DNA indicated that in contrast to the parental NIH/3T3 transformed cell lines (pT, T12N/5a, NS-1) all the nude-passaged immunogenic variants (pT-nude, T12N/5a-nude, NS-1-nude) contained newly acquired ecotropic-related proviruses. Immediately after in vitro establishment, these tumors displayed multiple integration sites as assessed by analysis of 3' proviral-cellular junctions. Long term in vitro culture of one of the cell lines (pT-nude) resulted in a cell line (pT-nude/vitro) that was clonal or oligo-clonal with respect to viral integration. Northern blot analysis established that the new proviruses were actively transcribed in all the immunogenic variants. To assess whether the somatically acquired ecotropic proviral sequences encode for target structures recognized by specific CTL, obtained after immunization of NIH mice with pT-nude, the parental cell line pT was transfected with plasmids containing the entire AKV MuLV genome, the cloned AKV gag or env genes. Screening of transfectants for their ability to stimulate the production of TNF by anti-pT-nude effectors indicated that cells transfected with the entire ecotropic virus or with MuLV-env gene products could be recognized by an NIH anti-pT-nude CTL line and NIH anti-pT-nude Kq-restricted CTL clones as well as the immunizing target pT-nude. 相似文献
75.
Cerminati Sebastián Paoletti Luciana Peirú Salvador Menzella Hugo G. Castelli María Eugenia 《Applied microbiology and biotechnology》2018,102(16):6997-7005
Applied Microbiology and Biotechnology - βγ-crystallin has emerged as a superfamily of structurally homologous proteins with representatives across all domains of life. A major portion of... 相似文献
76.
Margherita Strolin Benedetti Enrico Frigerio Paola Tocchetti Giannantonio Brianceschi Maria Grazia Castelli Cinzia Pellizzoni Philippe Dostert 《Chirality》1995,7(4):285-289
Reboxetine, (RS)-2-[(RS)-α-(2-ethoxyphenoxy)benzyl]morpholine methanesulphonate, is a racemic compound and consists of a mixture of the (R,R)- and (S,S)-enantiomers. In this study, brain and plasma levels of both enantiomers were determined in mice and rats after oral administration of reboxetine at doses (1.1 mg/kg, mouse; 20 mg/kg, rat) twice the respective ED50 values in the antireserpine test. Plasma and brain concentrations of each enantiomer were measured up to 6 h postdosing using an HPLC method with fluorimetric detection after derivatization with a chiral agent (FLEC). In mice and rats, brain and plasma levels of the (R,R)-enantiomer were always higher than those of the (S,S)-enantiomer. After normalization for dose, the mean AUC0-tz values of both the (R,R)- and (S,S)-enantiomers in mouse brain were about 23 and 32 times higher than in rat brain, respectively. In plasma, the corrected mean AUC0-tz values were about 5 (R,R) and 10 (S,S) times higher in mice than in rats. These results provide evidence for the higher bioavailability and/or lower clearance of both enantiomers in mice than in rats, and for a higher penetration of both enantiomers into mouse brain compared to rat brain. © 1995 Wiley-Liss, Inc. 相似文献
77.
Influence of caffeine on 3,4‐methylenedioxymethamphetamine‐induced dopaminergic neuron degeneration and neuroinflammation is age‐dependent 下载免费PDF全文
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Arabella Mazzocchi Andrea Anichini Chiara Castelli Marialuisa Sensi Francesca Poli Carlo Russo Giorgio Parmiani 《Cancer immunology, immunotherapy : CII》1990,32(1):13-21
Summary The specificity analysis of a CD3+, WT31+, CD8+ cytotoxic T lymphocyte (CTL) clone (CTL 49), isolated from peripheral blood lymphocytes of a melanoma patient (no. 665) after mixed lymphocyte culture with an HLA-A2+ allogeneic lymphoblastoid cell line (VSKB-LCL), revealed that CTL 49 could lyse, in addition to HLA-A2+ lines, autologous HLA-A2– melanoma (Me665/2) and K562 targets. Killing of VSKB-LCL, but not of Me665/2, could be inhibited by anti-CD3 and by anti-HLA-A2 antibodies or by modulation of the CD3 complex. Cold-target competition studies showed that K562, but not VSKB-LCL, could compete with Me665/2 for lysis by CTL 49. However, unlike K562, Me665/2 could be lysed by CTL 49 in a Ca2+-independent fashion in 4 h and 18 h assays. CTL 49 expressed mRNA specific for tumor necrosis factor (TNF) and, to a lesser extent, for lymphotoxin (TNF). Exposure of the clone to anti-CD3 antibodies induced the expression of interferon(IFN)--specific and the up-regulation of TNF- and TNF-specific mRNA. Antibodies to TNF, TNF and IFN reduced the lysis of Me665/2, but not of K562, by CTL 49 in 18-h cytotoxic assays. Antibodies to TNF and to IFN almost completely inhibited the lysis seen on Me665/2 (but not on K562), in 96-h assays, by supernatants isolated from VSKB-LCL- or anti-CD3-stimulated CTL 49 cells. Taken together, these data indicate that major-histocompatibility-complex-independent lysis of autologous tumor cells and of natural killer reference targets by the same alloreactive T cell clone are activities related at the level of target recognition but distinct at the level of the lytic hit. Thus, efficient lysis of autologous tumor cells results from a complex mechanism based upon direct effector-target interaction as well as on cytokine-mediated cytolytic effects. 相似文献
80.