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Evidence of molecular heterogeneity for generalised glycogenosis between and within breeds of cattle 总被引：1，自引：0，他引：1
PJ HEALY PJ NICHOLLS F. MARTINIUK† S. TZALL† R. HIRSCHHORN† JMcC HOWELL† 《Australian veterinary journal》1995,72(8):309-311
SUMMARY Northern analyses revealed normal levels of acidic α-glucosidase mRNA in cultured fibroblasts from a Shorthorn calf affected with glycogenosis but a gross deficiency in an affected Brahman calf. Analyses of acidic α-glucosidase activity, relative to that of other lysosomal enzymes, in blood mononuclear cells revealed greater variation within and between Brahman herds than Shorthorn herds. A Msp1 restriction fragment length polymorphism associated with glycogenosis in Brahmans was not found in Shorthorns. These results are considered in relation to molecular heterogeneity for AAG deficiency in cattle and its implications for disease control programs. 相似文献
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HOWELL FC 《Science (New York, N.Y.)》1959,130(3379):831-844
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We examine poverty's effect in two ways. First, we study the relationship between poverty and capacity for innovation in the U.S. states; second, we study the combined effects of poverty and innovation capacity on U.S. state economic output and employment. Because many of the relationships among poverty, innovation capacity and economic performance are simultaneous, we employ the Arellano Bond Difference GMM estimator to estimate various models using panel data (1980–1999). The findings reveal a negative indirect effect of socio‐economic need (poverty) on human and U.S. state and local financial innovation capacity, though there is no empirical link between poverty and federal financial capacity. We find no statistically significant evidence of the contemporaneous effect of poverty on state economic performance, holding innovation capacity constant. This suggests that poverty primarily affects state economic performance indirectly through reduction of innovation capacity. Overall, our findings suggest that U.S. officials ought to be concerned about the role poverty plays in diminishing their state economies' capacity to innovate. 相似文献
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The use of a breast-height core for estimating wood densityof the whole stem has been examined for British-grown Sitkaspruce. Regression equations have been derived for stem lengthsto 7 cm and 18 cm top diameter over bark and the precision ofthe estimates determined for both between- and within-site comparisons. The breast-height sampling technique is considered to be ofpractical value for demonstrating differences of density of15 kg m–3 or more, depending on the number of samplestaken, when a comparison is made between sites; when a comparisonis made within a site, the results show that the method canbe used to demonstrate differences of 8 kg m–3 or more.It clearly offers scope for the nondestructive examination ofthe effect of silvicultural operations on wood density and yieldsof wood substance. 相似文献
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Abstract. The effect of different levels of organic enrichment on benthic productivity was studied over a 16-week period in trays of sediment placed in a fertilized seawater pond. Primary and secondary planktonic production were also monitored. The exploitation of these sources of food by juvenile sole and their growth and survival over an 8-week period were assessed.
The colonization of the sediments showed a marked succession. Nematodes were numerically the most abundant group and reached a peak after about 8 weeks. This was followed by a peak in the abundance of epibenthic copepods after 11 weeks. The maximum numbers of poiychaetes and larger Crustacea (mainly amphipods) occurred at the end of the trial (15 weeks). The high-organic sediment supported fewer polychaetes and copepods than either the low- or medium-organic sediments. The species composition of the benthos varied both with the level of organic enrichment and with time. Peaks of zooplankton concentrations of 23 to 25 organisms/l occurred during the spring and late summer. There was some evidence of an inverse relationship between zooplankton abundance and standing crop of algae, as indicated by chlorophyll a concentrations.
Harpacticoid copepods were the dominant food item consumed by small (21-50mm total length) sole. Polychaetes, amphipods and Crangon spp. were exploited by large (61-90mm total length) sole to a much greater extent, though harpacticoid copepods were also commonly taken.
The percentage increase in length of the juvenile sole at low-, medium- and high-organic levels was 108, 146 and 152 respectively. Survival, however, was highest (100%) on the untreated sediment and lowest (57%) at the medium-organic level. 相似文献
The colonization of the sediments showed a marked succession. Nematodes were numerically the most abundant group and reached a peak after about 8 weeks. This was followed by a peak in the abundance of epibenthic copepods after 11 weeks. The maximum numbers of poiychaetes and larger Crustacea (mainly amphipods) occurred at the end of the trial (15 weeks). The high-organic sediment supported fewer polychaetes and copepods than either the low- or medium-organic sediments. The species composition of the benthos varied both with the level of organic enrichment and with time. Peaks of zooplankton concentrations of 23 to 25 organisms/l occurred during the spring and late summer. There was some evidence of an inverse relationship between zooplankton abundance and standing crop of algae, as indicated by chlorophyll a concentrations.
Harpacticoid copepods were the dominant food item consumed by small (21-50mm total length) sole. Polychaetes, amphipods and Crangon spp. were exploited by large (61-90mm total length) sole to a much greater extent, though harpacticoid copepods were also commonly taken.
The percentage increase in length of the juvenile sole at low-, medium- and high-organic levels was 108, 146 and 152 respectively. Survival, however, was highest (100%) on the untreated sediment and lowest (57%) at the medium-organic level. 相似文献
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A generalized additive model (GAM) was constructed to separate and quantify the effects of fishery‐based (operational) and oceanographic parameters on the bigeye tuna (Thunnus obesus) catch rates at Palmyra Atoll in the central Tropical Pacific. Bigeye catch, the number of hooks per set, and set location from 4884 longline sets spanning January 1994 to December 2003 were used with a temporally corresponding El Niño‐Southern Oscillation (ENSO) indicator built from sea surface height (SSH) data. Observations of environmental data combined with the results from the GAM indicated that there is an increase in bigeye catch rates corresponding to an increase in eastward advection during the winter months of El Niño events. A seasonal pattern with higher bigeye catch rates from December to April and a spatial pattern with higher rates to the northeast and northwest of the atoll were observed during this study period. It is hypothesized that the combination of the eastward advection of the warm pool coupled with vertical changes in temperature during the winter months of El Niño events increases the availability of bigeye tuna in this region. This increase in availability may be due to a change in exploitable population size, location, or both. 相似文献
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Abstract The common sole, Solea solea (L.), readily spawns naturally in captivity. This paper reviews the conditions and procedures used to obtain natural spawning from captive broodstocks and describes the characteristics of egg production. Spawning has been obtained under a wide range of conditions. The time of year has varied, even at the same location, but analysis of published data shows the temperature at which it commenced was related directly to the minimum temperature of the previous winter. Annual relative fecundity has varied from 11 to 141 eggs/g of female with a tendency, although not statistically significant, for the higher values to have occurred following winter temperatures of less than about 12°C. Variations in egg size and fertilization rate have not correlated with larval viability which has been consistently high. 相似文献