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排序方式: 共有311条查询结果,搜索用时 15 毫秒
111.
The present study sought to examine the effect of 5 weeks of training with minimalist footwear on oxygen consumption during walking and running. Thirteen college-aged students (male n = 7, female n = 6, age: 21.7±1.4 years, height: 168.9±8.8 cm, weight: 70.4±15.8 kg, VO2max: 46.6±6.6 ml·kg−1·min−1) participated in the present investigation. The participants did not have experience with minimalist footwear. Participants underwent metabolic testing during walking (5.6 km·hr−1), light running (7.2 km·hr−1), and moderate running (9.6 km·hr−1). The participants completed this assessment barefoot, in running shoes, and in minimalist footwear in a randomized order. The participants underwent 5 weeks of training with the minimalist footwear. Afterwards, participants repeated the metabolic testing. Data was analyzed via repeated measures ANOVA. The analysis revealed a significant (F4,32= 7.576, =0.408, p ≤ 0.001) interaction effect (time × treatment × speed). During the initial assessment, the minimalist footwear condition resulted in greater oxygen consumption at 9.6 km·hr−1 (p ≤ 0.05) compared to the barefoot condition, while the running shoe condition resulted in greater oxygen consumption than both the barefoot and minimalist condition at 7.2 and 9.6 km·hr−1. At post-testing the minimalist footwear was not different at any speed compared to the barefoot condition (p> 0.12). This study suggests that initially minimalist footwear results in greater oxygen consumption than running barefoot, however; with utilization the oxygen consumption becomes similar. 相似文献
112.
Youqiao Ma Gerald Farrell Yuliya Semenova Hau Ping Chan Hongzhou Zhang Qiang Wu 《Plasmonics (Norwell, Mass.)》2013,8(2):1259-1263
In this paper, a novel metal-dielectric waveguide structure is proposed to support hybrid long range surface plasmon polaritons (LRSPPs) with a highly confined mode field. The simulation results showed that our proposed structure has better mode confinement and propagation length compared to that of conventional dielectric-loaded surface plasmon polaritons (DLSPPs) waveguides. This structure offers greater flexibility for the design of surface plasmon polaritons (SPPs) waveguides by altering the trade-off between mode confinement and propagation length. The proposed structure has significant potential for application in highly integrated photonic circuits. 相似文献
113.
Janne Koch Jann Hau Jan Pravsgaard Christensen Henrik Elvang Jensen Morten Bagge Hansen Klaus Rieneck 《PloS one》2013,8(3)
Few experimental models are available for the study of natural resistance to cancer. One of them is the SR/CR (spontaneous regression/complete resistance) mouse model in which natural resistance to a variety of cancer types appeared to be inherited in SR/CR strains of BALB/c and C57BL/6 mice. The genetic, cellular, and molecular effector mechanisms in this model are largely unknown, but cells from the innate immune system may play a significant role. In contrast to previous observations, the cancer resistance was limited to S180 sarcoma cancer cells. We were unable to confirm previous observations of resistance to EL-4 lymphoma cells and J774A.1 monocyte-macrophage cancer cells. The cancer resistance against S180 sarcoma cells could be transferred to susceptible non-resistant BALB/c mice as well as C57BL/6 mice after depletion of both CD4+/CD8+ leukocytes and B-cells from SR/CR mice. In the responding recipient mice, the cancer disappeared gradually following infiltration of a large number of polymorphonuclear granulocytes and remarkably few lymphocytes in the remaining tumor tissues. This study confirmed that the in vivo growth and spread of cancer cells depend on a complex interplay between the cancer cells and the host organism. Here, hereditary components of the immune system, most likely the innate part, played a crucial role in this interplay and lead to resistance to a single experimental cancer type. The fact that leukocytes depleted of both CD4+/CD8+ and B cells from the cancer resistant donor mice could be transferred to inhibit S180 cancer cell growth in susceptible recipient mice support the vision of an efficient and adverse event free immunotherapy in future selected cancer types. 相似文献
114.
Paramastri Y Royo F Eberova J Carlsson HE Sajuthi D Fernstrom AL Pamungkas J Hau J 《Journal of medical primatology》2007,36(6):355-364
BACKGROUND AND METHODS: Quantitative enzyme-immunoassays of urinary and fecal immunoglobulin A (IgA), cortisol and 11-17-dioxoandrostanes (11,17-DOA), and serum cortisol in eight metabolic-cage-housed female cynomolgus monkeys were performed. The monkeys were divided into two groups, B and NB. Group B animals were blood sampled every 6 hours, whereas Group NB animals were not handled/blood sampled. RESULTS: No differences were recorded between the amounts of feces and urine excreted by the two groups. Group B animals excreted more urinary cortisol than did Group NB animals indicating that restraint-blood sampling resulted in a stress response. Excreted amounts of IgA and 11,17-DOA (urine and feces) did not differ between the groups. CONCLUSIONS: Urinary cortisol was a reliable marker of the stress associated with repeated blood sampling. Declining amounts of excreted urinary cortisol indicated that cynomolgus monkeys acclimated quickly to repeated blood sampling in metabolism cages. Within and between animal variation in amounts of feces voided demonstrated the importance of expressing fecal markers as 'amounts excreted per time unit per kg body weight' rather than just measuring the concentrations in fecal samples. 相似文献
115.
116.
Context matters: female aggression and testosterone in a year-round territorial neotropical songbird (Thryothorus leucotis) 总被引:1,自引:0,他引:1
Gill SA Alfson ED Hau M 《Proceedings. Biological sciences / The Royal Society》2007,274(1622):2187-2194
Testosterone promotes aggressive behaviour in male vertebrates during the breeding season, but the importance of testosterone in female aggression remains unclear. Testosterone has both beneficial and detrimental effects on behaviour and physiology, prompting the hypothesis that selection favours an association between aggression and testosterone only in certain contexts in which intense or persistent aggression may be beneficial. We tested this hypothesis in a year-round territorial female buff-breasted wrens (Thryothorus leucotis), by exposing free-living females to experimental intrusions in different social (either single female or male, or paired decoys) and seasonal (pre-breeding or breeding) contexts. Females responded more aggressively to intrusions by females and pairs than to males. However, female intrusions elicited stronger responses during pre-breeding, whereas responses to pair intrusions were more intense during breeding. Territorial females had elevated testosterone levels after female intrusions and intermediate levels after pair intrusions during pre-breeding, but the levels of testosterone remained low after these intrusions during breeding. These results demonstrate seasonal differences in circulating testosterone following territorial aggression in female buff-breasted wrens and are suggestive of differences according to social context as well. Context-dependent elevation of testosterone implies that selection acts directly on female vertebrates to shape patterns of testosterone secretion. 相似文献
117.
Su Guo Xing Yu Bing Jun Zhang Wen Hau Liu You Liang 《Plant Physiology and Biochemistry》2007,45(8):560-566
Polyamines (PAs) are assumed to perform their functions through their oxidative product such as gamma-aminobutyric acid (GABA) formation. However, there is only limited information on the interrelation between PA degradation and GABA accumulation under salt stress. In order to reveal a quantitative correlation between PA oxidation and GABA accumulation, the effects of treatments with different NaCl concentrations, along with aminoguanidine (AG, a specific inhibitor of diamine oxidases (DAO; EC: 1.4.3.6)) and a recovery test from salt stress on endogenous free PAs, gamma-aminobutyric acid (GABA) accumulation and DAO activity were determined in roots of soybean [Glycine max (L.) Merr.] cultivar Suxie-1. The results showed that the levels of putrescine (Put), cadaverine (Cad), and spermidine (Spd) decreased significantly with increasing salt concentrations. This occurred because salt stress strongly promoted DAO activity to stimulate PA degradation. GABA accumulation increased with growing NaCl concentrations, about an 11- to 17-fold increase as compared with the control plants. AG treatment increased the accumulation of endogenous free PAs as a result of a strong retardation of DAO activity, but decreased GABA accumulation. The recovery for 6 days in 1/2 Hoagland solution from 100mM NaCl stress resulted in a decrease in DAO activity, a rebound of PA levels and a simultaneous reduction of GABA content. A close correlation was observed between the changes in DAO activity and GABA accumulation. The results indicated that higher GABA accumulation (about 39%) induced by salt stress could come from PA degradation, suggesting that PAs might perform their functions through GABA formation under salt stress. 相似文献
118.
Ra Chae Hun Sunwoo In Yung Nguyen Trung Hau Sukwong Pailin Sirisuk Phunlap Jeong Gwi-Taek Kim Sung-Koo 《Bioprocess and biosystems engineering》2019,42(9):1559-1559
Bioprocess and Biosystems Engineering - Unfortunately, the author name was wrongly published as Pailin Sukwang.instead of Pailin Sukwong. 相似文献
119.
Takushi Nomura Hiroyuki Yamamoto Masako Nishizawa Trang Thi Thu Hau Shigeyoshi Harada Hiroshi Ishii Sayuri Seki Midori Nakamura-Hoshi Midori Okazaki Sachie Daigen Ai Kawana-Tachikawa Noriyo Nagata Naoko Iwata-Yoshikawa Nozomi Shiwa Shun Iida Harutaka Katano Tadaki Suzuki Eun-Sil Park Ken Maeda Yuriko Suzaki Yasushi Ami Tetsuro Matano 《PLoS pathogens》2021,17(7)
SARS-CoV-2 infection presents clinical manifestations ranging from asymptomatic to fatal respiratory failure. Despite the induction of functional SARS-CoV-2-specific CD8+ T-cell responses in convalescent individuals, the role of virus-specific CD8+ T-cell responses in the control of SARS-CoV-2 replication remains unknown. In the present study, we show that subacute SARS-CoV-2 replication can be controlled in the absence of CD8+ T cells in cynomolgus macaques. Eight macaques were intranasally inoculated with 105 or 106 TCID50 of SARS-CoV-2, and three of the eight macaques were treated with a monoclonal anti-CD8 antibody on days 5 and 7 post-infection. In these three macaques, CD8+ T cells were undetectable on day 7 and thereafter, while virus-specific CD8+ T-cell responses were induced in the remaining five untreated animals. Viral RNA was detected in nasopharyngeal swabs for 10–17 days post-infection in all macaques, and the kinetics of viral RNA levels in pharyngeal swabs and plasma neutralizing antibody titers were comparable between the anti-CD8 antibody treated and untreated animals. SARS-CoV-2 RNA was detected in the pharyngeal mucosa and/or retropharyngeal lymph node obtained at necropsy on day 21 in two of the untreated group but undetectable in all macaques treated with anti-CD8 antibody. CD8+ T-cell responses may contribute to viral control in SARS-CoV-2 infection, but our results indicate possible containment of subacute viral replication in the absence of CD8+ T cells, implying that CD8+ T-cell dysfunction may not solely lead to viral control failure. 相似文献
120.
Gaurav Bajaj Andrew M. Hau Peter Hsu Philip R. Gafken Michael I. Schimerlik Jane E. Ishmael 《Biochemical and biophysical research communications》2014
N-methyl-d-aspartate (NMDA) receptors are calcium-permeable ion channels assembled from four subunits that each have a common membrane topology. The intracellular carboxyl terminal domain (CTD) of each subunit varies in length, is least conserved between subunits, and binds multiple intracellular proteins. We defined a region of interest in the GluN2A CTD, downstream of well-characterized membrane-proximal motifs, that shares only 29% sequence similarity with the equivalent region of GluN2B. GluN2A (amino acids 875–1029) was fused to GST and used as a bait to identify proteins from mouse brain with the potential to bind GluN2A as a function of calcium. Using mass spectrometry we identified calmodulin as a calcium-dependent GluN2A binding partner. Equilibrium fluorescence spectroscopy experiments indicate that Ca2+/calmodulin binds GluN2A with high affinity (5.2 ± 2.4 nM) in vitro. Direct interaction of Ca2+/calmodulin with GluN2A was not affected by disruption of classic sequence motifs associated with Ca2+/calmodulin target recognition, but was critically dependent upon Trp-1014. These findings provide new insight into the potential of Ca2+/calmodulin, previously considered a GluN1-binding partner, to influence NMDA receptors by direct association. 相似文献