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41.
John M. MacGregor John E. Rush Nancy J. Laste Rebecca L. Malakoff Suzanne M. Cunningham Natalie Aronow Daniel J. Hall Justin Williams Lori L. Price 《Journal of Veterinary Cardiology》2011,13(4):251-260
Hypothesis/ObjectivesTo describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications.Animals, materials and methodsOne hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits.ResultsAll cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1–870).ConclusionPimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats. 相似文献
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43.
Spatial variation of soil enzyme activities and microbial functional diversity in temperate alley cropping systems 总被引:1,自引:0,他引:1
Nancy W. Mungai Peter P. Motavalli Robert J. Kremer Kelly A. Nelson 《Biology and Fertility of Soils》2005,42(2):129-136
Spatially dependent patterns in microbial properties may exist in temperate alley cropping systems due to differences in litter quality and microclimate in areas under trees compared to those in the alleys. The effect of tree row location was evaluated for its impact on soil enzyme activities and Biolog substrate use patterns. Soils were sampled to a depth of 30 cm at the tree row and at the middle of the alley at two sites: a 21-year-old pecan (Carya illinoinensis)/bluegrass (Poa trivials) intercrop (Pecan site) and a 12-year-old silver maple (Acer saccharinum)/soybean (Glycine max)–maize (Zea mays) rotation (Maple site). Sampling was done in fall 2001 and summer 2002. β-Glucosidase activities, Biolog patterns expressed as average well color (AWC), substrate richness, and Shannon diversity index, and total Kjeldahl nitrogen (TKN) were significantly higher (P<0.05) in the tree row than at the middle of the alley for surface soils at the Pecan site. Fluorescein diacetate (FDA) hydrolytic activity was also higher at the tree row for soils sampled in the fall, but did not differ significantly for soils sampled in the summer. At the Maple site, AWC and substrate richness were significantly higher at the tree row for soils sampled in 2001. Soil volumetric water content and temperature were generally lower in the tree row at the Maple site. The results of this study suggest that functionally different microbial populations may be present under pecan trees compared to cropped alleys which may promote disparities in nutrient availability necessitating differential long-term nutrient management in such alley cropping systems. 相似文献
44.
Nancy I. LópezAmy T. Austin Osvaldo E. SalaBeatriz S. Méndez 《Soil biology & biochemistry》2003,35(12):1609-1613
We studied controls on nitrification in an undisturbed water-limited ecosystem by inhibiting autotrophic nitrifying bacteria in soils with varying levels of vegetative cover. The activity of nitrifying bacteria was disrupted using nitrapyrin, 2-chloro-6-(trichloromethyl)-pyridine, under field conditions in three microenvironments (underneath shrubs, next to grasses and in bare soil). Ammonia-oxidising bacteria were detected by PCR analysis of DNA in soils. The inhibition of nitrification changed the concentrations of NO3− and NH4+ in the soil, while the microenvironment was most important in determining the response of bacteria to the inhibitor. Nitrapyrin application resulted in a significant (p<0.05) reduction in soil NO3− concentration (39%) and a significant increase (p<0.001) in soil NH4+ concentration (41%). Untreated bare-soil microenvironments had the lowest concentrations of NH4+ (1.57 μg/g of dry soil) and NO3− (0.49 μg/g of dry soil) when compared to the other microenvironments, and showed the highest impacts of nitrification inhibition. For example, NH4+ concentrations increased 288% and NO3− concentrations decreased 60% in inhibited bare-soil microenvironments. In contrast, untreated microenvironments underneath shrubs had the highest levels of NH4+ (10.01 μg/g of dry soil) and NO3− (0.69 μg/g of dry soil), but showed no significant effects of inhibition of nitrification on soil nitrogen concentrations. 相似文献
45.
Sotelo A Argote RM Moreno RI Flores NI Diaz M 《Journal of agricultural and food chemistry》2003,51(9):2821-2825
The nutritive and toxicological values of the dry seeds, germinated seeds, and string beans of Erythrina americana were studied using raw and boiled samples. Raw germinated seeds had a higher protein content and lower fiber content than dry seeds. The whole string bean had lower protein content and higher fiber content. However, the seeds of the green pod showed the same protein concentration as the dry seeds (dry basis). Boiling and elimination of broth was beneficial in diminishing the alkaloid concentration in all the samples. The trypsin inhibitors, lectins, and tannins were also diminished as was expected. The raw string bean showed the lowest LD(50). Although the total essential amino acids content of the boiled germinated seeds was increased, the quality of protein, protein efficiency ratio (PER), was lower than in boiled dry seeds, and in these, the PER was similar to the control (casein). The present results suggest that for the protein quality and low alkaloid content, the boiled dry seeds and string beans could be used for animal feeding. It could be interesting to test the raw string beans in ruminants since in this stage E. americana showed the lowest toxicity. 相似文献
46.
Judith A. Hudson DVM PhD Susan T. Finn-Bodner DVM MS Joan R. Coates DVM Donald C. Sorjonen DVM MS Stephen T. Simpson DVM MS James C. Wright DVM PhD Jan E. Steiss DVM PhD Nancy R. Cox DVM PhD Dana M. Vaughn DVM PhD Starr C. Miller BS Scott A. Brown DVM PhD Phillip D. Garrett DVM MS 《Veterinary radiology & ultrasound》1995,36(6):542-547
Doppler ultrasonography of the spinal cord was performed in 34 normal, anesthetized dogs following hemilaminectomy. This study was part of an investigation to evaluate the efficacy of a 21-aminosteroid compound and high dose methylprednisolone for the treatment of spinal cord trauma. Grey-scale images of the canine spinal cord were similar to those described for the spinal cord of people. Doppler waveforms of intraparenchymal spinal arteries exhibited high end diastolic blood flow velocities, indicating low resistance to flow. Doppler values (mean ± SD) for arteries immediately ventrolateral to the central canal were: Peak Systolic Velocity = 5.78 ± 2.5 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Minimum Diastolic Velocity = 3.5 ± 1.62 cm/sec, Mean Velocity = 4.45 ± 1.96 cm/sec, Systolic/Diastolic ratio = 169 ± 0.19, Pulsatility Index = 0.53 ± 0.09, and Resistance Index = 0.4 ± 0.06. 相似文献
47.
48.
Effects of forest patch size on avian diversity 总被引:10,自引:2,他引:8
Nancy E. McIntyre 《Landscape Ecology》1995,10(2):85-99
The effects of landscape patchiness on the diversity of birds of the Georgia Piedmont were investigated during 1993. Birds were sampled along line transects within relatively large (10–13.25 ha) and small (less than 3.25 ha) forest patches located within nonforest agricultural landscapes. Patterns of habitat use in these patches were compared to those in contiguous forest patches larger than 13.25 ha. Analysis of variance revealed significant differences in diversity between large and small woodlots and between contiguous and fragmented landscapes, especially in terms of the numbers of edge and interior species and winter-resident, summer-resident, and year-round birds observed. 相似文献
49.
Sheep were dosed orally with diazinon at 450 and 600 mg/kg: residues of diazinon were determined in the blood, brain, liver, kidney cortex and medulla, muscle, fat and rumen contents at intervals after dosing, and cholinesterase activities in the erythrocytes and the brain were determined at the same intervals. The relations between residues, cholinesterase activity and clinical symptoms are discussed from the points of view of their diagnostic value and the possibility of undesirable residues occurring in poisoned animals. Rough estimates of the residues of two metabolites, hydroxydiazinon and dehydro-diazinon, in one sheep are also discussed. The oxygen analogue of diazinon was not detected although it was specifically sought. 相似文献
50.
Nancy W. Axinn 《Agriculture and Human Values》1988,5(1-2):69-76
In this paper, the author points out that although by-passed by international development assistance in many parts of the world, women have been providing skill and labor for agricultural production, as well as subsistence of food, water and firewood for their families. Some of the assumptions which have contributed to the marginal attention to women as agriculturalists in international development assistance programs are reviewed. Factors contributing to these assumptions, examples of achievements in development projects and persistent problems are discussed. Some issues which continue to challenge national policy makers in developing countries as well as donors are identified. The author notes that while various donors and organizations address bits and pieces of the issues intermittently, a systematic, organized and universally shared approach to the issues, within a nation state or on a global basis is lacking. She concludes that just as agricultural production inputs and information need to be modified to fit the unique constraints of any ecological niche, similarly, modifications must be made in development assistance programs to fit the specific needs of women in their agricultural roles and cultural settings. 相似文献