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111.
White LJ Dressendorfer RH Muller SM Ferguson MA 《Journal of strength and conditioning research / National Strength & Conditioning Association》2003,17(2):319-323
The purpose of this study was to examine whether substituting 50% of run training volume with cycling ("cross-training") would maintain 3,000-m race time and estimated Vo(2)max in competitive female distance runners during a 5-week recuperative phase. Eleven collegiate runners were randomly assigned to either the run training-only (R) group (n = 6) or the cycle training (R/C) group (n = 5), which cross-trained on alternate days. The groups trained daily at a reduced intensity (75-80% of maximum heart rate). Training volume was similar to the competitive season (40-50 mi x wk(-1)) except that cycling represented 50% of volume for the R/C group. On follow-up, 3,000-m time was 1.4% (9 seconds) slower in the R group and 3.4% (22 seconds) slower in the R/C group. No important change in estimated Vo(2)max was found for either group. It was concluded that cycle cross-training adequately maintained aerobic performance during the recuperative phase between the cross-country and track seasons, comparable to the primary sport of running. 相似文献
112.
Notch signalling in the regulation of peripheral T-cell function 总被引:3,自引:0,他引:3
Mckenzie GJ Young LL Briend E Lamb JR Dallman MJ Champion BR 《Seminars in cell & developmental biology》2003,14(2):127-134
The Notch signalling pathway plays a highly-conserved role in regulating the cellular differentiation and proliferation events that characterise pattern formation in the embryo. As cells in the embryo respond to environmental signals, similarly T-cells in the peripheral immune system must monitor their environment for antigens and respond accordingly by entering one of several potential differentiation pathways. Recent studies have identified a role for the Notch pathway in regulating the responses of T-cells in the periphery. In this review, we discuss these findings in the context of the Notch signalling pathway's role as an orchestrator of cellular differentiation, and propose a central role for Notch as a regulator of immune system function. 相似文献
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Secondary structure is evaluated for determining evolutionary relationships between catalytic RNA molecules that are so distantly
related they are scarcely alignable. The ribonucleoproteins RNase P (P) and RNase MRP (MRP) have been suggested to be evolutionarily
related because of similarities in both function and secondary structure. However, their RNA sequences cannot be aligned with
any confidence, and this leads to uncertainty in any trees inferred from sequences. We report several approaches to using
secondary structures for inferring evolutionary trees and emphasize quantitative tests to demonstrate that evolutionary information
can be recovered. For P and MRP, three hypotheses for the relatedness are considered. The first is that MRP is derived from
P in early eukaryotes. The next is that MRP is derived from P from an early endosymbiont. The third is that both P and MRP
evolved in the RNA-world (and the need for MRP has since been lost in prokaryotes). Quantitative comparisons of the pRNA and
mrpRNA secondary structures have found that the possibility of an organellar origin of MRP is unlikely. In addition, comparison
of secondary structures support the identity of an RNase P–like sequence in the maize chloroplast genome. Overall, it is concluded
that RNA secondary structure is useful for evaluating evolutionary relatedness, even with sequences that cannot be aligned
with confidence.
Received: 19 July 1999 / Accepted: 3 May 2000 相似文献
116.
Cyclin Partners Determine Pho85 Protein Kinase Substrate Specificity In Vitro and In Vivo: Control of Glycogen Biosynthesis by Pcl8 and Pcl10 总被引:10,自引:2,他引:8
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117.
Lesley Gill 《American anthropologist》1999,101(3):681-682
The Gender/Sexuality Reader: Culture, History, Political Economy. Roger N. Lancaster and Micaela di Leonardo. eds. New York; Routledge, 1997. 574 pp. 相似文献
118.
High‐frequency binge eating predicts weight gain among veterans receiving behavioral weight loss treatments
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Lesley Cottrell Carrie Rishel Christa Lilly Scott Cottrell Aaron Metzger Halima Ahmadi Bo Wang Xiaoming Li Bonita Stanton 《PloS one》2015,10(5)
In this study, we examined how adolescents compare monitoring efforts by their parents to those of a "good parent" standard and assessed the impact of these comparisons on adolescent self-disclosure and risk behavior and their perceptions of their parents'' monitoring knowledge. Survey responses from 519 adolescents (12–17 years) at baseline of a larger, longitudinal study examining parental monitoring and adolescent risk were examined. Adolescents’ “good parent comparisons” differed greatly by monitoring areas (e.g., telephone use, health, money); however, between 5.5% and 25.8% of adolescents believed their parents needed to monitor their activities more than they currently were monitoring. Alternatively, between 8.5% and 23.8% of adolescents believed their parents needed to monitor their activities less often. These perceptions significantly distinguished adolescents in terms of their level of disclosure, perceived monitoring knowledge, and risk involvement. Adolescents who viewed their parents as needing to monitor more were less likely to disclose information to their parents (p<.001), less likely to perceive their parents as having greater monitoring knowledge (p<.001), and more likely to be involved in a risk behaviors (p<.001) than adolescents who perceived their parents needed no change. Adolescent disclosure to a parent is a powerful predictor of adolescent risk and poor health outcomes. These findings demonstrate that adolescents'' comparisons of their parents'' monitoring efforts can predict differences in adolescent disclosure and future risk. Obtaining adolescent "good parent" comparisons may successfully identify intervention opportunities with the adolescent and parent by noting the areas of need and direction of monitoring improvement. 相似文献