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42.
Furazolidone induces a cardiotoxicosis when fed in toxic concentrations to newly hatched ducklings. This preliminary experiment was designed to determine if creatine kinase (CK) isoenzymic activities or other serum analytes would be useful as indicators of these cardiac alterations. Sera from 12 ducklings (six fed a control ration and six fed the control ration with 700 mg furazolidone added per kg of feed [700 ppm] for 28 days) were analyzed for CK isoenzymic activities, electrolytes, nitrogenous metabolites, hepatic enzymic activities, bilirubin, and glucose. Statistically significant differences between control and treated groups were detected for creatine kinase MB (CK-MB, cardiac muscle origin) isoenzymic activity and bilirubin, potassium, calcium, and total carbon dioxide concentrations. Differences other than CK-MB isoenzymic activity were generally explained by factors related to the toxicosis or sample handling. These findings suggest that CK-MB isoenzymic activity may be useful to detect and monitor the progress of cardiac injury in furazolidone toxicosis, thereby increasing the usefulness of this model of dilated cardiomyopathy. Our findings, analyzed on the Kodak Ektachem 700 Dry Chemistry Analyzer, are compared with serum chemistry values reported in the literature. 相似文献
43.
44.
An Economic Opportunity Survey was conducted on dairy farms in the North West Province of Cameroon. Results showed that median
(range) number of cows in milk per farm was zero point six (0–4) and six (3–12) in the zero grazing and transhumance systems,
respectively. Medians (range) of three (0–24) and four (3–10) litres of milk were sold per farm per day, corresponding to
30% and 60% of milk produced. 24% and 13% of total cattle per herd were milking cows in the zero grazing and transhumance
systems respectively. Median milk production per cow on one day was two (0–25) and two (1–3) litres. Median calf production
interval was 14.5 (12–25) and. 21.5 (14–29) months. More milk produced per day represented the best economic opportunity in
both systems while reduced age at first calving and longer lactation length were the next in both. Wastage of milk through
spoilage from poor hygiene and lack of cooling was a major problem. Holstein cows, which were in the zero grazing system,
had unexpectedly short lactations. Constraints identified led to the setting up of interventions of training and advice for
farmers and of better nutrition. 相似文献
45.
T. J. Sullivan J. R. Webb K. U. Snyder A. T. Herlihy B. J. Cosby 《Water, air, and soil pollution》2007,182(1-4):57-71
A geologic classification scheme was combined with elevation to test hypotheses regarding watershed sensitivity to acidic deposition using available regional spatial data and to delimit a high-interest area for streamwater acidification sensitivity within the Southern Appalachian Mountains region. It covered only 28% of the region, and yet included almost all known streams that have low acid neutralizing capacity (ANC ≤20 μeq l?1) or that are acidic (ANC ≤0). The five-class geologic classification scheme was developed based on recent lithologic maps and streamwater chemistry data for 909 sites. The vast majority of the sampled streams that had ANC ≤20 μeq l?1 and that were totally underlainby a single geologic sensitivity class occurred in the siliceous class, which is represented by such lithologies as sandstone and quartzite. Streamwater acid-base chemistry throughout the region was also found to be associated with a number of watershed features that were mapped for the entire region, in addition to lithology and elevation, including ecoregion, physiographic province, soils type, forest type and watershed area. Logistic regression was used to model the presence/absence of acid-sensitive streams throughout the region. 相似文献
46.
S. R. Aston I. Thornton J. S. Webb J. B. Purves B. L. Milford 《Water, air, and soil pollution》1974,3(3):321-325
The trace element composition of stream sediments from catchments contaminated by past and present mining activities has been used to indicate the trace element status of associated waters. The paper discusses the possibility of using geochemical reconnaissance maps based on the analysis of stream sediments as an ancillary aid to water quality evaluation. 相似文献
47.
Lee N Benichi H Takeno Y Takeda S Webb J Huntington E Furusawa A 《Science (New York, N.Y.)》2011,332(6027):330-333
We report on the experimental quantum teleportation of strongly nonclassical wave packets of light. To perform this full quantum operation while preserving and retrieving the fragile nonclassicality of the input state, we have developed a broadband, zero-dispersion teleportation apparatus that works in conjunction with time-resolved state preparation equipment. Our approach brings within experimental reach a whole new set of hybrid protocols involving discrete- and continuous-variable techniques in quantum information processing for optical sciences. 相似文献
48.
Adherent bacterial colonization in the pathogenesis of osteomyelitis 总被引:12,自引:0,他引:12
Direct scanning electron microscopy of material obtained during surgical debridement of osteomyelitic bone showed that the infecting bacteria grew in coherent microcolonies in an adherent biofilm so extensive it often obscured the infected bone surfaces. Transmission electron microscopy showed this biofilm to have a fibrous matrix, to contain some host cells, and to contain many bacteria around which matrix fibers were often concentrated. Many bacterial morphotypes were present in these biofilms, and each bacterium was surrounded by exopolysaccharide polymers, which are known to mediate formation of microcolonies and adhesion of bacteria to surfaces in natural ecosystems and in infections related biomaterials. The adherent mode of growth may reduce the susceptibility of these organisms to host clearance mechanisms and antibiotic therapy and thus may be a fundamental factor in acute and chronic osteomyelitis. 相似文献
49.
50.
The various isotope effects on the superconducting transition temperature of Mo(2)B and W(2)B have been measured. Together with resistivity data they indicate that the d-shell forms a highly stable electron configuration for molybdenum and tungsten. This leads to an understanding of high superconducting transition temperatures. 相似文献