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71.
Background
Pulmonary inflammation, oxidants-antioxidants imbalance, as well as innate and adaptive immunity have been proposed as playing a key role in the development of COPD. The role of vitamins, as assessed either by food frequency questionnaires or measured in serum levels, have been reported to improve pulmonary function, reduce exacerbations and improve symptoms. Vitamin supplements have therefore been proposed to be a potentially useful additive to COPD therapy.Methods
A systematic literature review was performed on the association of vitamins and COPD. The role of vitamin supplements in COPD was then evaluated.Conclusions
The results of this review showed that various vitamins (vitamin C, D, E, A, beta and alpha carotene) are associated with improvement in features of COPD such as symptoms, exacerbations and pulmonary function. High vitamin intake would probably reduce the annual decline of FEV1. There were no studies that showed benefit from vitamin supplementation in improved symptoms, decreased hospitalization or pulmonary function. 相似文献72.
J. Todd Streelman C. Puchulutegui A. L. Bass T. Thys H. Dewar S. A. Karl 《Molecular ecology resources》2003,3(2):247-249
We report the isolation and characterization of CAn microsatellite loci from the Mola mola genome using a variation of the hybrid capture method. Five loci exhibit high levels of heterozygocity and two show significant sequence similarity to genes from the closely related Fugu rubripes. These microsatellite markers should be useful in multidisciplinary efforts to understand population characteristics of the giant ocean sunfish. 相似文献
73.
Phytostimulatory effect of Azospirillum brasilense wild type and mutant strains altered in IAA production on wheat 总被引:2,自引:0,他引:2
Dobbelaere Sofie Croonenborghs Anja Thys Amber Vande Broek Ann Vanderleyden Jos 《Plant and Soil》1999,212(2):153-162
Auxin production by Azospirillum is believed to play a major role in the observed plant growth promoting effect. By using
different genetically modified strains, the contribution of auxin biosynthesis by A. brasilense in altering root morphology
was evaluated in a plate assay. Inoculation with the wild type strains A. brasilense Sp245 and Sp7 resulted in a strong decrease
in root length and increase in root hair formation. This effect was abolished when inoculating with an ipdC mutant of A. brasilense.
The ipdC gene encodes a key enzyme in the IPyA pathway of IAA synthesis by A. brasilense. On the other hand, the observed
auxin effect was further enhanced by adding tryptophan, a precursor of IAA, to the plates and could be mimicked by replacing
the Azospirillum cells by a particular concentration of IAA. Furthermore, particular mutants (rpoN, scrp) and transconjugants
(extra copy of ipdC) of A. brasilense were tested in the plate assay. Together, these results confirm the important role of
IAA produced by Azospirillum in altering root morphology and illustrate the power of combining genetic tools and bioassays
to elucidate the mechanism of a beneficial Azospirillum-plant interaction.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
74.
Edward C. Pope Graeme C. Hays Tierney M. Thys Thomas K. Doyle David W. Sims Nuno Queiroz Victoria J. Hobson Lukas Kubicek Jonathan D. R. Houghton 《Reviews in Fish Biology and Fisheries》2010,20(4):471-487
Relatively little is known about the biology and ecology of the world’s largest (heaviest) bony fish, the ocean sunfish Mola mola, despite its worldwide occurrence in temperate and tropical seas. Studies are now emerging that require many common perceptions
about sunfish behaviour and ecology to be re-examined. Indeed, the long-held view that ocean sunfish are an inactive, passively
drifting species seems to be entirely misplaced. Technological advances in marine telemetry are revealing distinct behavioural
patterns and protracted seasonal movements. Extensive forays by ocean sunfish into the deep ocean have been documented and
broad-scale surveys, together with molecular and laboratory based techniques, are addressing the connectivity and trophic
role of these animals. These emerging molecular and movement studies suggest that local distinct populations may be prone
to depletion through bycatch in commercial fisheries. Rising interest in ocean sunfish, highlighted by the increase in recent
publications, warrants a thorough review of the biology and ecology of this species. Here we review the taxonomy, morphology,
geography, diet, locomotion, vision, movements, foraging ecology, reproduction and species interactions of M. mola. We present a summary of current conservation issues and suggest methods for addressing fundamental gaps in our knowledge. 相似文献
75.
Lloyd's equation (Lloyd, 1967 b) has been applied to the calculation of record time in the 1 500 meters foot race from VO2 max. Twenty-eight healthy male subjects participated in this investigation. Record times decrease with increasing VO2 max. The theoretical curve plotted from Lloyd's equation is consistent with this trend. Moreover, the relationship between calculated record times (TRc) and measured record times (TRm) is highly significant (TRc = 74.3 + 0.7 TRm; r = 0.883; P less than 0.001). These results validate Lloyd's equation and hypothesis. 相似文献
76.
G Camus H Thys C Nopere 《Comptes rendus des séances de la Société de biologie et de ses filiales》1985,179(1):114-121
Margaria's equation (1976)--describing the relationship between the minimum time necessary to cover a distance equal or longer than 1,000 m (record-time TR) and the maximal oxygen consumption (VO2 max)--has been modified in order to be applied to the calculation of TR in the 800 m foot race. Fifteen subjects participated in this study (VO2 max = 63 +/- 3.5 ml O2 X kg-1 X min-1, measured TR = 131 +/- 10 seconds). It has been found the TR calculated from Margaria's equation (TRc) are underestimated (TRc = 104 +/- 10 seconds). By taking into account the actual energy cost of running (0.19 ml O2 X kg-1 X m-1) and the kinetics of VO2 at the onset of exercise, TRc averaged 133 +/- 8.5 seconds. Moreover, the relationship between TRc and measured TR (TRm) is highly significant (TRc = 50.4 + 0.65 TRm; r = 0.75; P less than 0.01). These results validate Margaria's equation modifications. 相似文献
77.
78.
79.
Maarten Hoogewijs Tom Rijsselaere Sarne De Vliegher Emilie Vanhaesebrouck Catharina De Schauwer Jan Govaere Mirjan Thys Geert Hoflack Ann Van Soom Aart de Kruif 《Theriogenology》2010,74(1):118-126
Three experiments were conducted to evaluate the impact of centrifugation on cooled and frozen preservation of equine semen. A standard centrifugation protocol (600 × g for 10 min = CP1) was compared to four protocols with increasing g-force and decreased time period (600 × g, 1200 × g, 1800 × g and 2400 × g for 5 min for CP2, 3, 4, and 5, respectively) and to an uncentrifuged negative control. In experiment 1, the influence of the different CPs on sperm loss was evaluated by calculating the total number of sperm cells in 90% of the supernatant. Moreover, the effect on semen quality following centrifugation was assessed by monitoring several sperm parameters (membrane integrity using SYBR14-PI, acrosomal status using PSA-FITC, percentage total motility (TM), percentage progressive motility (PM) and beat cross frequency (BCF) obtained with computer assisted sperm analysis (CASA)) immediately after centrifugation and daily during chilled storage for 3 d. The use of CP1 resulted in a sperm loss of 22%. Increasing the centrifugation force to 1800 × g and 2400 × g for 5 min led to significantly lower sperm losses (7.4% and 2.1%, respectively; P < 0.05). Compared to the uncentrifuged samples, centrifugation of semen resulted in a better sperm quality after chilled storage. There were minimal differences between the CPs although total motility was lower for CP2 than for the other treatments (P < 0.005). In experiment 2, the centrifuged samples were cryopreserved using a standard freezing protocol and analyzed immediately upon thawing. Samples centrifuged according to CP2 resulted in a higher BCF (P < 0.005), whereas CP3 and CP5 yielded a lower BCF (P < 0.05) when compared to CP1. There were no post thaw differences between CP1 and CP4. In experiment 3, DNA integrity of the different samples was analyzed using TUNEL. Although DNA integrity decreased over time, CP had no impact. In conclusion, the loss of sperm cells in the supernatant after centrifugation can be substantially reduced by increasing the g-force up to 1800 × g or 2400 × g for a shorter period of time (5 min) compared to the standard protocol without apparent changes in semen quality, resulting in a considerable increase in the number of insemination doses per ejaculate. 相似文献
80.
Utilization of muscle elasticity in exercise 总被引:3,自引:0,他引:3