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21.
Establishment of the temperature-salinity relationship in the ocean has concerned oceanographers for decades because of its importance for understanding ocean circulation. High-resolution measurements in the ocean mixed layer are used to show that temperature and salinity gradients on horizontal scales of 20 meters to 10 kilometers tend to compensate in their effect on density. These observations support the notion of a horizontal mixing in the mixed layer that depends on density gradient.  相似文献   
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OBJECTIVE: To determine whether increased sensitivity to pharmacologic agents was a general property of equine exertional myopathies, including polysaccharide storage myopathy (PSSM) in Quarter Horses. ANIMALS: 5 adult Quarter Horses with exertional rhabdomyolysis and abnormal polysaccharide accumulation in skeletal muscle and 4 clinically normal adult Quarter or Quarter-type horses. PROCEDURES: Twitch time course measurements and contracture responses to various concentrations of caffeine and halothane for small bundles of intact external intercostal muscle fibers were measured in all horses. RESULTS: Caffeine contracture threshold of muscles from Quarter Horses with PSSM was not different from that of clinically normal horses (5 mM in both groups). Muscles from horses with PSSM and from clinically normal horses did not have contracture in response to up to 2% halothane. CONCLUSIONS AND CLINICAL RELEVANCE: Results were in contrast to the increased sensitivity to caffeine and halothane for muscles from Thoroughbreds with recurrent exertional rhabdomyolysis (RER). Although clinical signs of muscular stiffness after exercise are similar between Quarter Horses with PSSM and Thoroughbreds with RER, these breeds appear to have 2 distinct myopathies with different pathophysiologic bases. Unlike RER in Thoroughbreds, PSSM in Quarter Horses does not appear to be accompanied by a defect in regulation of muscle contraction.  相似文献   
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OBJECTIVE: To determine whether abnormal regulation of muscle contraction similar to that associated with malignant hyperthermia (MH) was evident in intact external intercostal muscle cells from Thoroughbreds with recurrent exertional rhabdomyolysis (RER). ANIMALS: 5 adult Thoroughbred horses with RER and 7 clinically normal adult Thoroughbred or mixed-breed horses. PROCEDURES: Twitch time course variables and contracture responses to various concentrations of potassium, caffeine, and halothane were measured in small bundles of intact external intercostal muscle cells from clinically normal horses and horses with RER. RESULTS: Threshold for significant contracture induced by potassium depolarization was lower for RER-affected muscles, compared with normal muscles, although the relationship between potassium concentration and membrane potential were not different. Thresholds for contracture induced by caffeine and halothane were also lower for RER-affected muscles, compared with normal muscles. Lower thresholds for caffeine- and halothane-induced contractures, as well as depolarization-elicited contractures, in RER-affected muscles suggest a defect in myoplasmic calcium regulation. CONCLUSIONS AND CLINICAL RELEVANCE: Regulation of muscle contraction is abnormal in Thoroughbreds with RER. The specific defect may be attributable to abnormal intracellular calcium regulation. Knowledge of the specific defect involved in RER may lead to improved prevention and treatment of RER-affected horses.  相似文献   
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The German trade network of pig holdings and related enterprises for the time period of 01 June 2006-31 December 2008 was analyzed. Available data comprised of the entire German trade information with about 121,287 pig premises and their links in the pork production chain (breeders to slaughter houses). During the study period, 330,000 trade connections between premises were recorded. Communities which are large scale structures comprising of premises which are in close trade contact with each other were detected by modularity maximization. Almost 97% of the pig holdings could be assigned to one of nine major communities. Contacts between communities are rare. Trade communities do not only form spatial clusters, but were also associated with specific regions within the territory of Germany. Communities are to some extent separated by 'trade borders', which may impede disease spread. Interestingly, the trade borders often failed to match with administrative borders of the German federal states. This finding is important, because it illustrates the need for new strategies of cross-border disease management strategies.  相似文献   
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? The treatment of soiled hygiene papers (HYP), such as diapers and sanitary napkins, added at a concentration of 10 percent (w/w) to separately collected municipal biowaste was tested at Biotechnishce Abfallverwertung (BTA)'s three stage mesophilic biogas plant in Munich. The study aimed to establish the feasibility of cobiogasification of hygiene papers and biowaste. Parameters measured were: Efficiency of plastics and inerts separation; Mass balances; Organic and inorganic dry residues; COD; C:N ratio; Heavy metal content; Bacterial counts; Fiber analysis of suspension; Residues; Effluent for hemicellulose, cellulose and lignin; Biogas yield; and Quality. In the conditioning stage, the hygiene papers (HYP) (10 percent) were completely suspended with municipal solid waste. The dry materials balance of the conditioning unit resulted in an increase of 1.5 percent of the screenings, corresponding exactly to the amount of the added plastics. Heavy metal contents in the residues were well below limits established by German compost quality guidelines. Plate counts of the sums of Enterobacteriae and Salmonellae revealed that addition of soiled HYPs does not increase risk of contamination. Fermentation process and yield did not differ from control; biogas contained about 70-75 percent methane and most organic pollutants measured were undetectable.  相似文献   
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This study was conducted to measure the concentration of cefquinome in the endometrium of mares after intrauterine treatment and to evaluate associated inflammation. Mares (n = 14) were randomly assigned to one of the following groups: (i) control (n = 4) were either not treated (n = 2) or received (n = 2) lactated Ringer's intrauterine for 1 or 3 days; (ii) treated mares (n = 10) received intrauterine cefquinome for 1 or 3 days. After at least 10 days had passed following the last treatment and ovulation, mares were given Prostaglandin F2α (PGF2α) and were randomly assigned to an alternate treatment. Endometrial biopsy samples were taken at 2, 8, 24 and 48 h, or at 4, 12 and 36 h, after the last treatment. Biopsy samples were taken at the same time points from control mares (n = 2) and lactated Ringer-treated mares (n = 2). Cefquinome concentrations were quantified using a high-performance liquid chromatography (HPLC) assay and inflammation was assessed using haematoxylin and eosin (H&E)-stained sections. Concentrations of cefquinome [559 (1 day) and 595 μg/g (3 days) at 2 h, and 403 (1 day) and 370 μg/g (3 days) at 4 h] were similar between treatment groups at 2 and 4 h after treatment (p > 0.05). At 8 h, as well as at 24 and 48 h, concentrations were greater in the 3-day group (17 vs 301 μg/g, 3 vs 80 μg/g and 0.1 vs 0.2 μg/g, respectively) (p < 0.05). No significant differences (p > 0.05) in the inflammatory response at 2–48 h after treatment were found between groups.  相似文献   
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Objective To investigate factors associated with low vitamin D status of alpacas at pasture in southern Australia. Design A 2‐year survey of alpacas from two farms in South Australia and three in Victoria. Blood samples were collected from 20 to 30 alpacas on each farm on five occasions each year. Breed, gender, age and fleece colour of animals were recorded. Method Blood samples were assayed for plasma 2.5‐hydroxycholecalciferol (25‐OH D3) and plasma inorganic phosphorus (Pi). Data sets from 802 animal samples were analysed by multiple regression to determine variables associated with low vitamin D status of alpacas. The relationship between plasma 25‐OH D3 and plasma Pi was also investigated. Results Vitamin D status was significantly affected by month of sampling, with low values in late winter and high values in summer. Plasma vitamin D concentrations increased with age, were higher in alpacas with light fleeces than in those with dark fleeces and were also higher in the Suri than in the Huacaya breed. Plasma Pi concentrations were generally lower in alpacas with plasma 25‐OH D3 values < 25 nmol/L. Conclusions Young alpacas with dark fleeces are most at risk from vitamin D insufficiency in late winter in southern Australia. The present study indicates that plasma Pi values are not a reliable indicator of vitamin D status of alpacas as assessed by plasma 25‐OH D3 concentrations.  相似文献   
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