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11.
C. R. C. Sheppard K. Matheson J. C. Bythell P. Murphy C. Blair Myers B. Blake 《水产资源保护:海洋与淡水生态系统》1995,5(4):277-298
- 1 The nature and distribution of the coastal and shallow marine habitats of Anguilla in the Caribbean were examined using aerial photography coupled with extensive ground truth information.
- 2 The objective was to develop an accurate method of marine habitat mapping for the analysis of the marine ecosystem in order to develop a procedure for marine and coastal resource management.
- 3 This paper describes the method which was adopted as well as the biological results.
- 4 It is concluded that the management and sustainable use of the natural resources may be improved as a result of accurate habitat mapping.
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13.
L J Myers 《Veterinary Clinics of North America: Small Animal Practice》1991,21(2):389-389
The need to evaluate sensory function in the dog is discussed. A group of techniques that use innate behaviors (species-typical behaviors) and are effective in the evaluation of sensory function of domestic animals are described. Techniques to measure olfactory, gustatory, auditory, and visual function are included. 相似文献
14.
Jodi R. Viste Sherry L. Myers Baljit Singh Elemir Simko 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(1):33-37
Mammary carcinomas and adenocarcinomas (MACs) are relatively common tumors in cats. The postexcisional survival period of affected cats is inversely proportional to tumor size, but the reported median survival periods for different tumor size categories is quite variable. This variability diminishes the prognostic value of reported data. In our study, cats with MACs greater than 3 cm in diameter had a 12-month median survival period, whereas those with MACs less than 3 cm in diameter had a 21-month survival period. Survival periods for cats with MACs smaller than 3 cm ranged from 3 to 54 months; therefore, tumor size alone is of limited prognostic value in cats with MACs smaller than 3 cm in diameter. In cats with MACs larger than 3 cm in diameter, tumor size appears to have much higher prognostic relevance, because this study, as well as others, have indicated that cats with MACs greater than 3 cm in diameter have a poor prognosis, with median survival periods ranging from 4 to 12 months. 相似文献
15.
The National Coalition for Agricultural Safety and Health (NCASH) in 1988 addressed issues in agriculture and noted "a sense of urgency... arose from the recognition of the unabating epidemic of traumatic death and injury in American farming . . ." This article provides an update to the NCASH conference on traumatic injuries in agriculture, a history on how the facts and figures were arrived at for the NCASH conference, and a current report on the status of traumatic injuries in agriculture in the U.S. Fatal and nonfatal injuries are addressed along with national and regional surveillance systems. The Census of Fatal Occupational Injuries (CFOI) was used for reporting national agricultural production fatal injuries from 1992-1998 (25.8 deaths per 100,000 workers), the Traumatic Injury Surveillance of Farmers (TISF) 1993-1995 was used to report nonfatal injuries occurring nationally (7.5/100 workers), and Regional Rural Injury Studies I and II (RRIS-I and RRIS-II) were used to illustrate a regional approach along with in-depth, specific analyses. Fatality rates, which showed some decline in the 1980s, were fairly constant during the 1990s. Changes in nonfatal injury rates for this sector could not be assessed due to a lack of benchmark data. The main concerns identified in the 1989 NCASH report continue today: tractors are the leading cause of farm-related death due mostly to overturns; older farmers continue to be at the highest risk for farm fatalities; and traumatic injuries continue to be a major concern for youth living or working on U.S. farms. Fatal and nonfatal traumatic injuries associated with agricultural production are a major public health problem that needs to be addressed through comprehensive approaches that include further delineation of the problem, particularly in children and older adults, and identification of specific risk factors through analytic efforts. Continued development of relevant surveillance systems and implementation of appropriate interventions are the primary challenges for the current decade. 相似文献
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17.
Fever: reciprocal shift in brain sodium to calcium ratio as the set-point temperature rises 总被引:2,自引:0,他引:2
A bacterial pyrogen acts on the brain by disturbing the natural balance between two essential cations in the cerebral region involved in thermoregulation. After typhoid vaccine is administered to the unanesthetized cat, (45)Ca(2+) efflux into the third cerebral ventricle increases while (22)Na(+) is retained in hypothalamic tissue at the same time that the set-point temperature begins to rise. The subsequent rates of (22)Na(+) and (45)Ca(2+) efflux parallel the course of the bacterial fever but in a reciprocal fashion. This supports the theory that a change in the set-point temperature is determined by an alteration in the inherent ratio of Na(+) to Ca(2+) ions in the hypothalamus. 相似文献
18.
Advanced methods of phosphorus-31 nuclear magnetic resonance spectroscopy provided a method whereby biological phosphonates and phosphates can be determined on simple lipid fractions of biological origin. The spectra consist of two easily distinguished resonance bands; one corresponds to families of phosphonates, and the other corresponds to families of orthophosphates. 相似文献
19.
Tetrahydropapaveroline (THP), a dopamine-dopaldehyde condensation product, was delivered directly into the cerebral ventricle of rats automatically every 15 minutes for 12 days. The animals were given access to both water and ethylalcohol, the latter being presented in 12 concentrations from 3 to 30 percent. Within 3 to 6 days of the start of the infusion of THP, the rats, which normally rejected alcohol, drank alcohol solutions in increasingly excessive amounts; this was accompanied by symptoms that were similar to those of withdrawal and intoxication. These results provide evidence that an abnormal metabolite in the brain may produce the addictive state caused by alcoholic beverages. 相似文献
20.
Infants' discrimination of the duration of a rapid spectrum change in nonspeech signals 总被引:1,自引:0,他引:1
Two-month-old infants discriminated complex sinusoidal patterns that varied in the duration of their initial frequency transitions. Discrimination of these nonspeech sinusoidal patterns was a function of both the duration of the transitions and the total duration of the stimulus pattern. This contextual effect was observed even though the information specifying stimulus duration occurred after the transitional information. These findings parallel those observed with infants for perception of synthetic speech stimuli. Specialized speech processing capacities are thus not required to account for infants' sensitivity to contextual effects in acoustic signals, whether speech or nonspeech. 相似文献