Control of stress-dependent cardiac growth and gene expression by a microRNA   总被引：2，自引：0，他引：2  

van Rooij E  Sutherland LB  Qi X  Richardson JA  Hill J  Olson EN 《Science (New York, N.Y.)》2007,316(5824):575-579

The heart responds to diverse forms of stress by hypertrophic growth accompanied by fibrosis and eventual diminution of contractility, which results from down-regulation of alpha-myosin heavy chain (alphaMHC) and up-regulation of betaMHC, the primary contractile proteins of the heart. We found that a cardiac-specific microRNA (miR-208) encoded by an intron of the alphaMHC gene is required for cardiomyocyte hypertrophy, fibrosis, and expression of betaMHC in response to stress and hypothyroidism. Thus, the alphaMHC gene, in addition to encoding a major cardiac contractile protein, regulates cardiac growth and gene expression in response to stress and hormonal signaling through miR-208.  相似文献   

Seasonal variation in soluble soil carbon and nitrogen across a grassland productivity gradient     

Mark Farrell  Paul W. Hill  Richard D. Bardgett 《Soil biology & biochemistry》2011,43(4):835-844

Understanding the fate and turnover of the pools that comprise dissolved organic nitrogen (DON) in soil is key to determining its role in ecosystem functioning. We investigated seasonal changes of dissolved organic carbon (DOC) and nitrogen (DON) concentrations within four molecular weight (MW) size fractions across an altitudinal gradient (from lowland to montane systems), and quantified individual amino acids and amino acid constituents of oligopeptidic-N, as well as nitrate and ammonium. We tested two ideas: first, that DON is more abundant than DIN in low-productivity relative to high-productivity grassland ecosystems; and second, that the abundance of peptides and amino acids is likewise greater in low- than high-productivity grassland. The most productive site had a history of inorganic fertiliser application, and hence in this site alone DIN was more abundant than DON. Plant productivity varied 3-fold between the other sites, and DON was generally at higher concentrations in the sites of lower productivity both in absolute terms as well as relative to DIN, with a large increase observed in spring. The fraction containing the highest concentration of the DON had a MW of >100 kDa, and in summer and autumn this fraction was more abundant at the lowest productivity site. We conclude that relationships between the abundance of DON relative to DIN and ecosystem productivity is dependent on season, and hence more complex than previously suggested, and that peptides are a dynamic and potentially nutritionally significant component of DON.  相似文献   

Lakeshore diversity and rarity relationships along interacting disturbance gradients: catchment area, wave action and depth     

Paul A MorrisNicholas M Hill  Edward G ReekieHeather L Hewlin 《Biological conservation》2002,106(1):79-90

Diversity patterns of riparian plant communities have been associated with disturbance. Populations of a diversity of Atlantic Coastal Plain plants occur as disjuncts on shores of large catchment area lakes in Nova Scotia. These lakeshore communities contain rare plants with local, national and global rankings. The populations of rare plants are dynamic and their management requires an understanding of the relationship between disturbance and the survival of rare plants. This present study measured (overwinter wooden dowel removal) and observed disturbance along gradients of catchment area (CA), exposure and depth. In three separate experiments ranging from the landscape to the lake, to the single shoreline level, disturbance was linked to lake CA, exposure and depth, respectively. At all scales, disturbance was positively associated with the presence of rare species. The pattern of rare species richness over the river system was complex; at the within-lake level, the frequency of rare species per site was greatest in the intermediate CA lake while the pool of rare species was greatest in the largest CA lake. The findings focus field efforts on wide, exposed shorelines of large CA lakes where new rare plants continue to be discovered. In addition, the discrepancy between highest frequency of rare plants on intermediate CA lakes and highest species pools of rarities on large CA lakes, reinforces the need for larger protected area systems for the most naturally disturbed ecosystems which often support populations having a high turnover rate but a low site to site frequency.  相似文献   

Serologic diagnosis of encephalomyocarditis virus infection in swine by the microtiter serum neutralization test     

J J Zimmerman  H T Hill  G W Beran  M C Meetz 《Journal of veterinary diagnostic investigation》1990,2(4):347-350

  相似文献   

Risk factors associated with injuries in thoroughbred horses.   总被引：2，自引：0，他引：2  

H O Mohammed  T Hill  J Lowe 《Equine veterinary journal》1991,23(6):445-448

A case-control study was conducted on Thoroughbred horses to identify factors associated with the risk of breakdown on racetracks. A total of 310 cases (breakdowns) were identified from the Horse Identification Department records kept by the chief examining veterinarian of New York Racing Association. For each case, two control horses were selected randomly from the Daily Racing Form Inc. records. Multiple logistic regression analysis was used to identify and quantify the risk of factors associated with breakdown, while simultaneously controlling for the effect of other putative factors. Factors associated with risk of breakdown were: track (horses raced on Saratoga racetrack were at a lesser risk of breakdown), track composition/condition (turf tracks had a lower risk compared to dirt), number of seasons in race, racing in a later race, number of starts per year, the total number of starts, season (summer had a higher risk than winter or spring) and age of the horse.  相似文献   

A survey of bone fractures in the cat   总被引：1，自引：0，他引：1  

F. W. G. Hill 《The Journal of small animal practice》1977,18(7):457-463

A survey of 108 bone fractures in the cat was made over a 1 year period in a city practice in south west England. Seventy-three per cent involved the pelvic limb. The three bones most commonly affected were femur (38%), pelvis/sacrum (22%) and mandible (16%). Forty-five cases were the result of road accidents and 75% of cats were 2 years old or less.
Treatment of femoral shaft fractures by intramedullary pinning gave good results. The majority of proximal epiphyseal separations and femoral neck fractures responded well to conservative treatment. 'Cage rest' was used successfully to treat severely comminuted femoral shaft fractures. All cases of pelvic fracture were treated conservatively (up to 3 weeks 'cage rest'). Separation of the mandibular symphysis and fracture of the horizontal ramus healed readily. Repair of tibial (10%) and humeral (5%) fractures was without complications.  相似文献   

Influence of picolinic acid on the uptake of 65zinc-amino acid complexes by the everted rat gut   总被引：4，自引：0，他引：4  

D A Hill  E R Peo  A J Lewis 《Journal of animal science》1987,65(1):173-178

Three hundred fifty rats were used in three experiments to: 1) validate the everted gut procedure as an in vitro technique for estimating Zn absorption, 2) determine the effect of increasing ratios of picolinic acid (PA) to Zn on Zn absorption and 3) determine the effect of PA on absorption of Zn and amino acid complexes at pH 6, 7 and 8. In the first experiment the time delay between tissue collection with subsequent storage in ice-cold saline and start of tissue incubation was 0, 10, 20 or 30 min. A linear decrease was observed for 65Zn uptake with increasing delay time. Lysine absorption was not affected by delay time. In the second experiment, molar ratios of PA:Zn of 0, .5, 1.0, 1.5, 2.0 and 2.5 with Zn held constant were evaluated. A linear decrease in 65Zn absorption from 65ZnCl2 occurred as the molar ratio of PA to Zn increased. In the third experiment, 0 and 5 molar ratios of PA to a constant Zn level were evaluated using 65ZnCl2, 65Zn-14C-methionine (ZnMet) and 65Zn-3H-lysine (ZnLys) at pH 6, 7 and 8. The addition of PA decreased Zn absorption regardless of Zn source. The data suggest that the Zn sources used were of similar biological value. The data do not support the theory that PA facilitates Zn absorption.  相似文献   

Vaccination of mice and swine with a pseudorabies virus mutant lacking thymidine kinase activity.          下载免费PDF全文

M D McFarland  H T Hill 《Canadian journal of veterinary research》1987,51(3):340-344

A thymidine kinase deficient mutant of the Indiana-Funkhauser strain of pseudorabies virus was tested for its ability to stimulate protective immunity in mice and young pigs. Mice vaccinated intraperitoneally were protected from morbidity and mortality when challenged with 50 LD50 of virulent pseudorabies virus. Eight week old pigs were protected from serious morbidity and mortality when challenged with virulent pseudorabies virus. The thymidine kinase mutant was not shed from the nasal passages of pigs vaccinated intramuscularly, but did not prevent shedding of challenge virus.  相似文献   

Spinal abscess in a dog     

J Ndikuwera  D C Knottenbelt  J Lawrence  F W Hill 《The Veterinary record》1987,120(23):554-555

  相似文献   

Application of in vitro fertilisation techniques to obtain calves from valuable cows after slaughter.     

K P Xu  B Hill  K J Betteridge 《The Veterinary record》1992,130(10):204-206

The ovaries of two infertile cows of high breeding value were recovered after slaughter, and a total of 222 oocytes were obtained. Of these, 156 were classified as of good or fair quality and were subjected to in vitro maturation, in vitro fertilisation (using frozen semen from three bulls of high breeding value) and in vitro culture procedures. After eight days, 27 embryos were obtained, of which 13 were transferred fresh, and 14 were frozen. Three recipients of fresh embryos became pregnant; two calved and one aborted at four months. One of eight recipients of frozen-thawed embryos became pregnant but aborted at three months.  相似文献