排序方式： 共有26条查询结果，搜索用时 15 毫秒
1.
Björnsdóttir S Axelsson M Eksell P Sigurdsson H Carlsten J 《Equine veterinary journal》2000,32(3):268-272
The prevalence of degenerative joint disease (DJD) in the distal tarsal joints and the relation between radiographic and clinical signs compatible with the disease were estimated in a population of Icelandic horses used for riding. The material consisted of 614 horses age 6-12 years (mean age = 7.9 years). Radiographs with 3 projections of each tarsus were made and a clinical examination, including palpation of the medial aspect of the distal tarsus and motion evaluation of the hindlimbs before and after a flexion test of the tarsus, was performed. Radiographic signs of DJD in the distal tarsal joints were found in 30.3% of the horses and the prevalence was strongly correlated with age. Hindlimb lameness before and after flexion test and palpation abnormalities were significantly associated with the radiographic findings. The lameness was usually mild and, in most cases, detectable only after the flexion test. The prevalence of lameness was not significantly correlated with age. Lameness could not be predicted by details of the radiographic findings. 相似文献
2.
A small Plinian eruption of the Nevado del Ruiz volcano in Colombia ejected 3.5 x 10(10) kilograms of mixed dacite and andesite tephra on 13 November 1985, with a maximum column height of 31 kilometers above sea level. Small pyroclastic flows and surges, generated during the initial stage of the eruption, caused surface melting of approximately 10% of the volcano's ice cap, leading to meltwater floods. The erosive floods incorporated soils and loose sediments from the volcano's flanks and developed into lahars, which claimed at least 25,000 lives. 相似文献
3.
The Soufrière volcano in St. Vincent erupted from October 1971 to March 1972, as 80 x 10(6) m(3) of basaltic andesite lava was quietly extruded inside the mile-wide crater. The eruption was largely subaqueous, taking place in the 180-m-deep crater lake, and resulted in the emergence of a steep-sided island. The mild character of the eruption and the absence of seismic activity stand in direct contrast to the highly explosive character of the eruption of 1902 to 1903. 相似文献
4.
5.
Albert K. Imsland Snorri Gunnarsson A. Foss Benedikt Sigur?sson Sindri Sigur?sson 《Journal of the World Aquaculture Society》2009,40(6):762-770
We compared growth properties of spotted wolffish with initial mean weight (± SE) 3.65 (± 0.15) kg reared in shallow raceways at three different densities (50, 70, and 90 kg/m2, corresponding to approx. 170, 240, and 310 kg/m3) in a 447‐day‐long growth trial at ambient temperature (mean (± SD), 4.2 C ± 1.9). Growth in all three groups was comparable, but there was a trend toward higher growth at the highest density. Final mean weights (kg ± SE) were 4.90 (± 0.15), 4.80 (± 0.16), and 5.05 (± 0.11), at the 50, 70, and 90 kg/m2 density, respectively. Initially, growth rates were higher at the 90 kg/m2 density group compared to the two other densities, but overall growth rates were similar in all three groups. Feed conversion efficiency differed and was higher at the two highest densities compared to lowest density. The acid–base balance was influenced by the density treatment as there was a general trend toward higher partial pressure of CO2 and HCO in the 90 kg/m2 group. Calculated productivity increased almost linearly with increasing stocking density and was found to be 24, 42, and 66 g/m2/day at 50, 70, and 90 kg/m2, respectively. The results show that the optimum density conditions for farming large spotted wolffish, both with respect to growth rate, feed conversion, and productivity are at densities equal to or higher than 90 kg/m2. 相似文献
6.
Rupert PB Massey AP Sigurdsson ST Ferré-D'Amaré AR 《Science (New York, N.Y.)》2002,298(5597):1421-1424
The hairpin ribozyme catalyzes sequence-specific cleavage of RNA through transesterification of the scissile phosphate. Vanadate has previously been used as a transition state mimic of protein enzymes that catalyze the same reaction. Comparison of the 2.2 angstrom resolution structure of a vanadate-hairpin ribozyme complex with structures of precursor and product complexes reveals a rigid active site that makes more hydrogen bonds to the transition state than to the precursor or product. Because of the paucity of RNA functional groups capable of general acid-base or electrostatic catalysis, transition state stabilization is likely to be an important catalytic strategy for ribozymes. 相似文献
7.
Di Concetto S Michael Archer R Sigurdsson SF Clarke K 《Veterinary anaesthesia and analgesia》2007,34(1):67-69
OBSERVATIONS: A pony undergoing elective castration accidentally received an overdose of IV detomidine (200 microg kg(-1)) before anaesthesia was induced with ketamine and midazolam. A further 100 microg kg(-1) IV dose of detomidine was administered during anaesthesia. The mistake was recognized only when the animal failed to recover from anaesthesia in the expected time. The overdose (300 microg kg(-1) in total) was treated successfully with atipamezole, initially given IV and subsequently IM and titrated to effect to a total dose of 1100 microg kg(-1). The pony regained the standing position. A further injection of atipamezole (76 microg kg(-1) IM) was given 5 hours later to counteract slight signs of re-sedation. CONCLUSIONS: Atipamezole proved an effective antagonist for detomidine in a pony at an initial dose 3.65 x and a final total dose 3.9 x greater than the alpha2 agonist. 相似文献
8.
Rapid response by earth, atmospheric, and space scientists made possible diverse observations during the explosive phase of the 1979 eruption of Soufriere Volcano. The 11 reports that follow indicate that, with the availability of appropriate personnel, equipment, and logistical support, a significant body of geophysical data can be gathered on short notice at erupting volcanoes in remote parts of the world. 相似文献
9.
Milk quality in bulk tank milk(BTM)is measured by flow cytometry technology as total bacterial count(TBC)and somatic cell count(SCC).To investigate SCC problems,culture or PCR can be used to identify mastitis causing bacteria,e.g.,Mastit 4,a commercially available qPCR test.TBC in BTM can be investigated further using culture-based methods such as standard plate count,laboratory pasteurization count,coliform count,and spore counts.To our knowledge,no qPCR addressing the bacteria involved in TBC has been commercially introduced.The aim of this study is to evaluate a recently introduced 3-h qPCR test,TBC 4.The TBC 4 qPCR detects four target groups,Pseudomonas,Streptococci,Enterobacteriacea/Enterococcus,and Bacillus/Clostridia.These target groups relate to problems on the farm such as cooling,mastitis,environment,and silage.We will continue with new research to compare the TBC 4 qPCR test with traditional culture.For this study,BTM samples from different TBC intervals were selected based on Bacto Count results found at routine payment investigation at Eurofins laboratory(Vejen,Denmark).These samples were analyzed using TBC 4 qPCR assay within 24 h.In total,346 BTM samples were divided into six different intervals of colony forming units(CFU).For all four targets in each of the different intervals of CFU,the percent of positive samples,the average C_t-value,the percent of positive samples with C_t30 and C_t25 were calculated.For Pseudomonas,Streptococci,and Enterobacteriacea/Enterococcus,the number of positive samples with lower C_t-values(high bacteria content)correlated with the CFU mL~(–1).We found Enterobacteriacea/Enterococcus,Pseudomonas,and Streptococci in high number of bacteria(C_t25)in 25,19 and 56%of samples with CFU mL~(–1) between 50 001–100 000 and 53,44,and 39%in samples with CFU mL~(–1)100 000.The TBC 4 qPCR test showed to be a strong and fast tool for farmers,advisors and service technicians to address problems with high TBC and ensuring the delivery of good quality milk to the dairy. 相似文献
10.
Albert K. Imsland Snorri Gunnarsson A. Foss Lars Olav Sparboe Victor Øiestad Sindri Sigurðsson 《Journal of the World Aquaculture Society》2007,38(1):154-160
Abstract.— We compared growth properties of juvenile spotted wolffish with initial mean weight (±SE) 105.9 (±3.1) g reared in shallow raceways and conventional circular tanks in a 202-d-long growth trial at ambient temperature (approximately 4.0 C). From Day 41 onward, the fish in the shallow raceways was significantly larger, and final mean weights were 356.3 (±18.2) and 318.2 (±15.6), in the shallow raceways and the circular tanks, respectively. Overall, growth rates were 14% higher (0.62%/d) in the shallow raceway group compared to the circular tanks (0.52%/d). Feed conversion efficiency differed and was 17% higher in the shallow raceways (1.01) compared to the circular tanks (0.84). Correlation between adjacent growth rates was more profound in the circular tanks (mean Spearmans rank, r Sp = 0.38) than in the shallow raceways (mean r Sp = 0.15). This could indicate a stronger social hierarchy in conventional tanks leading to suppressed growth, which is in line with the growth data presented in this study. The findings of the present study may have important consequences for optimization of commercial production of spotted wolffish and could be applicable to other bottom-dwelling species. 相似文献