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941.
Dave Parrott Anthony Prickett Stéphane Pietravalle Thomas R. Etherington Mark Fletcher 《European Journal of Wildlife Research》2012,58(1):23-33
Walked spotlight transect surveys with distance sampling were used to estimate regional population densities of badger (Meles meles), fox (Vulpes vulpes) and brown hare (Lepus europaeus) in south-west England (Cornwall, Devon, Gloucestershire, Herefordshire) and Wales (Pembrokeshire, Borders, North Wales).
All regions were surveyed during spring 2006 with English regions re-surveyed in autumn 2006. In each region, surveys were
conducted in a random sample of 19.6 km2 areas (mean areas per region: spring = 19, autumn = 25). Within each survey area, a semi-random transect was established
in each of a random sample of fields (open habitat almost exclusively pasture). Transects were subsequently walked at night
with spotlights (mean transects per survey area: spring = 21, autumn = 21). Each area was surveyed twice during a season.
Total transect length per region ranged from 137 to 193 km in spring and 230 to 250 km in autumn. The mean density of species
per region was: badger 1.5–4.8 km−2, fox 1.0–4.0 km−2, hare 0.4–4.6 km−2. The study has provided baseline estimates of regional densities against which any future equivalent surveys can be compared.
It has also illustrated the practical application of large-scale walked distance sampling to surveys of British mammals. 相似文献
942.
Comfort P Fletcher C McMahon JJ 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(11):2970-2974
ABSTRACT: Comfort, P, Fletcher, C, and McMahon, JJ. Determination of optimal loading during the power clean, in collegiate athletes. J Strength Cond Res 26(11): 2970-2974, 2012-Although previous research has been performed in similar areas of study, the optimal load for the development of peak power during training remains controversial, and this has yet to be established in collegiate level athletes. The purpose of this study was to determine the optimal load to achieve peak power output during the power clean in collegiate athletes. Nineteen male collegiate athletes (age 21.5 ± 1.4 years; height 173.86 ± 7.98 cm; body mass 78.85 ± 8.67 kg) performed 3 repetitions of power cleans, while standing on a force platform, using loads of 30, 40, 50, 60, 70, and 80% of their predetermined 1-repetition maximum (1RM) power clean, in a randomized, counterbalanced order. Peak power output occurred at 70% 1RM (2,951.7 ± 931.71 W), which was significantly greater than the 30% (2,149.5 ± 406.98 W, p = 0.007), 40% (2,201.0 ± 438.82 W, p = 0.04), and 50% (2,231.1 ± 501.09 W, p = 0.05) conditions, although not significantly different when compared with the 60 and 80% 1RM loads. In addition, force increased with an increase in load, with peak force occurring at 80% 1RM (1,939.1 ± 320.97 N), which was significantly greater (p < 0.001) than the 30, 40, 50, and 60% 1RM loads but not significantly greater (p > 0.05) than the 70% 1RM load (1,921.2 ± 345.16 N). In contrast, there was no significant difference (p > 0.05) in rate of force development across loads. When training to maximize force and power, it may be advantageous to use loads equivalent to 60-80% of the 1RM, in collegiate level athletes. 相似文献
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946.
Jessica A Neal Kathryn L Fletcher J Justin McCormick Veronica M Maher 《BMC cell biology》2010,11(1):97
Background
DNA polymerase zeta (Polζ) is a specialized DNA polymerase that, unlike classical replicative polymerases, is capable of replicating past DNA lesions, i.e. of performing translesion synthesis (TLS). The catalytic subunit of hPolζ, hRev3, has been shown to play a critical role in DNA damage-induced mutagenesis in human cells, but less is known about the role of hRev7, the accessory subunit of hPolζ, in such mutagenesis. To address this question, we recently generated human fibroblasts with very significantly reduced levels of hRev7 protein and demonstrated that hRev7 is required to protect cells from ultraviolet(254 nm) (UV) radiation-induced cytotoxicity and mutagenesis (McNally et al., DNA Repair 7 (2008) 597-604). The goal of the present study was to determine whether hRev7 is similarly involved in the tolerance of DNA damage induced by benzo[a]pyrene diol epoxide (BPDE), the reactive form of the widespread environmental carcinogen benzo[a]pyrene. 相似文献947.
Histological studies on plaice tissues revealed mononuclear phagocytes emigrating through capillary endothelium in response to bloodborne foreign erythrocytes, with a >50% increase in circulating leucocytes within 2 h. Despite this rapid influx of leucocytes, cellular accumulation during peritoneal inflammatory responses was significantly slower than in mammals. In vitro studies with chemotaxis chambers revealed that random leucocyte migration was enhanced in the presence of endogenous chemostimulatory substances (inflammatory exudate fluid and endotoxin-activated plaice serum) although directional migration was not demonstrated. It is suggested that, compared with mammals, the slower accumulation of teleostean leucocytes at sites of injury is not due to a locomotory defect but possibly results from lower levels of endogenous chemoattractants being generated. 相似文献
948.
Successful culture of hematopoietic cells depends upon the growth of stromal cells. The growth of bone marrow stromal cells is best achieved when hydrocortisone is added to the culture medium. However, the hydrocortisone requirement is eliminated if the cultures are grown in an atmosphere of 5% CO2, 5% O2, and 90% N2 rather than 5% CO2 in air, which is more common. 相似文献
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950.
A multilocus linkage map of mouse chromosome 8 总被引:1,自引:0,他引:1
We present a genetic linkage map of mouse chromosome 8 that spans 53 cM and includes eight cloned loci. This map was derived from analysis of 100 progeny of an interspecific backcross between Mus spretus and Mus musculus domesticus. Genes that were mapped in this analysis include L7, Plat, Lpl, Ucp, Es, Mt-1, Um, and Tat. This analysis positions a new extremely proximal marker on chromosome 8, which is discussed as a potential candidate gene for the nervous locus. These linkage data will be useful for the mapping of additional loci on chromosome 8. 相似文献