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排序方式: 共有7163条查询结果,搜索用时 15 毫秒
1.
Abstract In a 2-year field survey, the phylloplane mycoflora on the haulm base of wheat was studied by the dilution plate technique. No significant colonisation was registered before the end of May. Cladosporium spp., 'white' and 'red' yeasts were found to be the most abundant fungi. 相似文献
2.
Patrizia Vaccino Heinz-Albert Becker Andrea Brandolini Francesco Salamini Benjamin Kilian 《Molecular genetics and genomics : MGG》2009,281(3):289-300
The celiac disease (CD) is an inflammatory condition characterized by injury to the lining of the small-intestine on exposure
to the gluten of wheat, barley and rye. The involvement of gluten in the CD syndrome has been studied in detail in bread wheat,
where a set of “toxic” and “immunogenic” peptides has been defined. For wheat diploid species, information on CD epitopes
is poor. In the present paper, we have adopted a genomic approach in order to understand the potential CD danger represented
by storage proteins in diploid wheat and sequenced a sufficiently large number of cDNA clones related to storage protein genes
of Triticum monococcum. Four bona fide toxic peptides and 13 immunogenic peptides were found. All the classes of storage proteins were shown to contain harmful
sequences. The major conclusion is that einkorn has the full potential to induce the CD syndrome, as already evident for polyploid
wheats. In addition, a complete overview of the storage protein gene arsenal in T. monococcum is provided, including a full-length HMW x-type sequence and two partial HMW y-type sequences.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
4.
Does maternal condition or predation risk influence small mammal population dynamics? 总被引:2,自引:0,他引:2
There is strong debate over whether the intrinsic traits of individuals or the extrinsic environment exert the greater influence on small mammal population dynamics. We test the roles of maternal effects (an intrinsic factor) and predation risk (an extrinsic factor) in the population dynamics of wild strain house mice using a 2-factor enclosure experiment. Pre-release supplemental feeding with a high-fat diet created female treatment founders that were 6–10% heavier than controls, a condition that we predicted would be passed on as a maternal effect. Predation risk was enhanced using regular application of predator (red fox Vulpes vulpes ) scats. Founder populations of six females and six males released into eight, 15×15 m enclosures showed near exponential population growth over 17 weeks (maximum 3 generations). But there were no responses to either treatment in terms of survival, inherited body weights, fecundity or population size. We suggest that elevated maternal condition may have only minor and transient intergenerational effects with little long-term consequence. We also suggest that the general significance of predator scats as a cue to predation risk to alter prey behaviour may have been overestimated. Hence our results question the role of either factor in causing long-term responses that influence condition to affect population processes. 相似文献
5.
Harbor seal ( Phoca vitulina ) haul-out site use may be affected by natural or anthropogenic factors. Here, we use an 11-yr (1997–2007) study of a seal colony located near a mariculture operation in Drakes Estero, California, to test for natural (El Niño-Southern Oscillation (ENSO), density-dependence, long-term trends) and anthropogenic (disturbance or displacement related to oyster production activities) factors that may influence the use of haul-out subsites. Annual mariculture related seal disturbance rates increased significantly with increases in oyster harvest ( r s = 0.55). Using generalized linear models (GLMs) ranked by best fit and Akaike's Information Criteria, ENSO and oyster production (as a proxy for disturbance/displacement) best explained the patterns of seal use at all three subsites near the mariculture operations, with effects being stronger at the two subsites closest to operations. Conversely, density-dependence and linear trend effects poorly explained the counts at these subsites. We conclude that a combination of ENSO and mariculture activities best explain the patterns of seal haul-out use during the breeding/pupping season at the seal haul-out sites closest to oyster activities. 相似文献
6.
Household‐level correlates of children's physical activity levels in and across 12 countries
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Deirdre M. Harrington Fiona Gillison Stephanie T. Broyles Jean‐Philippe Chaput Mikael Fogelholm Gang Hu Rebecca Kuriyan Anura Kurpad Allana G. LeBlanc Carol Maher Jose Maia Victor Matsudo Timothy Olds Vincent Onywera Olga L. Sarmiento Martyn Standage Mark S. Tremblay Catrine Tudor‐Locke Pei Zhao Peter T. Katzmarzyk for the ISCOLE Research Group 《Obesity (Silver Spring, Md.)》2016,24(10):2150-2157
7.
R T Francis R R Becker 《Comparative biochemistry and physiology. A, Comparative physiology》1984,79(1):109-113
The capability of Taricha granulosa to conserve hemoglobin upon in vivo hemolysis has been investigated. 59Fe incorporation into Taricha hemoglobin was similar in rate to mammals and birds. Phenylhydrazine-induced hemolysis resulted in comparatively low levels of 59Fe and no discernible amounts of hemoglobin excreted after 10 days. The addition of 59Fe Hb to Taricha circulation resulted in relatively low levels of 59Fe excretion and significant amounts of 59Fe incorporation into new hemoglobin within 10 days. 相似文献
8.
In Exp. 1A, hybrid mice (N = 10) were provided with food and 25% (v/v) ethanol as the only source of liquid for 72 h, beginning at the detection of the copulatory plug (08:00 h, Day 1). Control mice received food and tap water. Food consumption (P less than 0.001) but not total caloric intake (P greater than 0.05) was less for the alcohol-treated mice than the controls. Ethanol-derived calories averaged 35% of caloric intake during the 72 h of treatment. Alcohol-treated animals showed a dramatic weight loss until Day 5 while controls gained weight (P less than 0.05). Ethanol consumption did not influence pregnancy rate, litter size or litter weight. In Exp. 1B, animals were treated as in Exp. 1A, but were killed at various times between 24:00 h, Day 1, and 08:00 h, Day 4. Trunk blood was used to determine haematocrit and serum to determine alcohol concentration. Haematocrit was greater (P less than 0.05) for all alcohol-treated mice than for controls at all time periods sampled except one. Dehydration was therefore probably responsible for the weight loss seen in Exps 1A and 1B. Average blood alcohol concentrations fluctuated with time of day and day of treatment. Average maximum concentration was 91.4 mg ethanol/100 ml serum. In Exp. 2, hybrid mouse 2-cell embryos were cultured in vitro in 0 or 0.1% ethanol (Exp. 2A) and 0 or 1.0% ethanol (Exp. 2B) for 8 days.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
D Matthias E Engler L Will-Shahab H J Herrmann C H Becker 《Acta biologica et medica Germanica》1977,36(9):1279-1284
A 14-days' training of rats designed to adapt the animals to the procedure of blood-pressure measurement caused in the myocardium a decrease, in serum an increase in noradrenaline ( NA) content. The latter remained unchanged following 3 days of treatment with 2.5 mg depot angiotensin II (AII) but decreased by more than one-half in the myocardium of untreated animals, and increased in serum. Despite the considerable difference in myocardial NA content and blood-pressure behaviour, both trained and untrained rats showed the same morphological reactions following administration of A II. These myocardial alterations which largely correspond to the so-called epinephrine myocarditis should not therefore be due solely to NA action; rather, the involvement of A II should be considered also. 相似文献
10.
A. A. Moaty Sayed M. A. Hussein T. Becker 《Biomechanics and modeling in mechanobiology》2010,9(2):141-151
Lattice Boltzmann models (LBM) are rapidly showing their ability to simulate a lot of fluid dynamics problems that previously
required very complex approaches. This study presents a LBM for simulating diffusion–advection transport of substrate in a
2-D laminar flow. The model considers the substrate influx into a set of active cells placed inside the flow field. A new
innovative method was used to simulate the cells activity using the LBM by means of Michaelis–Menten kinetics. The model is
validated with some numerical benchmark problems and proved highly accurate results. After validation the model was used to
simulate the transport of oxygen substrates that diffuse in water to feed a set of active cartilage cells inside a new designed
bioreactor. 相似文献