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Jo?o A T Pigatto José L Laus Jaime M Santos Cristine Cerva Luciana S Cunha Valéria Ruoppolo Paulo S M Barros 《Journal of zoo and wildlife medicine》2005,36(4):702-705
The corneal endothelium is essential for the maintenance of the corneal transparency. The aim of this study was to examine the morphology of the endothelial surface and perform morphometric analysis of the normal corneal endothelial cells of the Magellanic penguin (Spheniscus magellanicus) using scanning electron microscopy. The present work demonstrates that the corneal endothelium of the Magellanic penguin is similar to those described in other vertebrates. 相似文献
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Lopera L Moro PL Chavez A Montes G Gonzales A Gilman RH 《Veterinary parasitology》2003,117(1-2):37-42
One hundred and six dogs (61 males and 45 females) were examined for Echinococcus granulosus infection in a farming cooperative in the central highlands of Peru during November 1998. Canine echinococcosis was diagnosed using direct microscopic examinations of purged feces following arecoline purging and a coproantigen-detection enzyme-linked immunosorbent assay (ELISA) for E. granulosus. Mean age was 2 years with a range of 3 months to 9 years. The overall prevalence of canine echinococcosis using the ELISA test was 79% (84/106). Seventy-four dogs were successfully purged with arecoline. The frequency of canine echinococcosis was 82 (61/74) and 34% (25/74) by the coproantigen ELISA test and arecoline purging, respectively. The sensitivity and specificity of the coproantigen ELISA test was 88 and 95%, respectively. We found this assay to be especially advantageous in remote geographical areas. In future control programs against echinococcosis in Peru and other areas where E. granulosus is endemic the coproantigen ELISA should be used for the surveillance of the dog population. 相似文献
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The aim of this work was to record the modifications of the form and amplitude of the electrocardiographic tracings during growth using the Dubois system and to study its sensibility to these physiological changes. This work was carried out on 179 healthy, young and adult Spanish-bred horses (98 females and 81 males). One electrocardiogram (ECG) was obtained from each horse using the Dubois leads system. The bifid shape deflection of the P wave was generally more frequent than the simple one in animals at 4 months of age or older. Amplitudes of the P2 component and of the simple positive wave presented significant differences (p < 0.01) between the age groups studied: animals up to 3 months in age and older than 2 years of age (highest amplitudes), and the rest of the animals (lowest amplitudes). Significant variations (p < 0.05) were found for the QS amplitude between animals of 1 month of age, and all the other groups. The multiple range analysis did not define a clear distribution of age groups for the amplitude of the T wave. It may therefore be concluded, that in the Spanish-bred horse up to 1 month of age, the form and amplitude of the QRS complex in the Dubois leads system differ from those of older animals. Thus, this study shows the sensibility of the Dubois leads system for detecting the electrocardiographic changes related to the growing process in the Spanish-bred horse. In addition, it provides standard values of electrocardiographic parameters in the Spanish-bred horse at different stages of growth. 相似文献
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J. Chatterjee A.K.A. Mandal S.A. Ranade Jaime A. Teixeira da Silva S.K. Datta 《Scientia Horticulturae》2006
An attempt was made to understand the molecular systematics and genetic differences between 10 original chrysanthemum cultivars and 11 mutants. The similarity among the cultivars and mutants varied from 0.17 to 0.90 using RAPD analyses, a simple but efficient method to distinguish cultivars and to assess parentage. Two distinct groups were found. Two cultivars were present as a separate group showing differences from all other cultivars. Mutants with different flower colour could be identified at the molecular level using RAPD technique holding promise to identify unique genes as SCAR markers. A high genetic distance among the different chrysanthemums showed that there exists a possibility of introgressing new and novel genes from the chrysanthemum gene pool. 相似文献
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Francisco J. Escobedo David J. Nowak John E. Wagner Carmen Luz De la Maza Manuel Rodríguez Daniel E. Crane Jaime Hernndez 《Urban Forestry & Urban Greening》2006,4(3-4):105-114
Santiago, Chile's semi-arid climate and urbanized environment poses a severe limitation for the establishment and maintenance of urban forests. Municipalities, or comunas, are the main stakeholders in the management of Santiago's public urban forests. A tenable hypothesis would be that as the socioeconomic level of a comuna increases, the better the condition of a comuna's urban forest. Unfortunately, there is little comprehensive information on management, public expenditure, and structure of Santiago's public and private urban forests. To examine this hypothesis, Santiago was divided into socioeconomic strata, then using air photo interpretation and stratified field sampling, urban forest structures were quantified by socioeconomic strata. In addition, interview surveys were used to determine municipal urban forest management and expenditures for different public urban forests based on socioeconomic strata. Urban forests in the high socioeconomic strata had fewer public trees, greater tree cover, tree and leaf area density, and leaf area index than lower socioeconomic strata. The percentage of total municipal budget allocated to public urban forest management was consistent among strata, but the total public urban forest budgets were greater in the high socioeconomic strata. Public urban forest structure is related to the socioeconomic strata of Santiago's different comunas. 相似文献
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Across the physiognomic types of the Orinoco llanos, periodic inventories and changes in land-use between 1982–1992 are estimated. Results indicate that the area under pastures and forest plantations is increased by 0.005337×106 km2, whilts reducing the area of croplands by 0.000119×106 km2. This is a net increase of 0.005218×106 km2. The gross carbon release is 174.66 Tg C per year to the atmosphere and transferring from cultivated and native vegetation to wood products (1.62 Tg C per year) and slash (1.18 Tg C per year). The processes of land preparation contribute 1.40 Tg C per year to the atmosphere. From the tree savannas, woodlands and forests 0.73 Tg C per year are estimated to have been transferred to the soil following clearance and burning over this period, and 1.05 Tg C per year from herbaceous savannas when were buried and decomposed at 0.84 Tg C per year. The estimate of carbon balance here by inventories and changes in land-use approach indicates that the Orinoco llanos is a sink of −17.53 Tg C per year. The carbon turnover time in the Orinoco system is 68 years, which provides a limited route for carbon sequestration. The calculated potential of the Orinoco llanos for storing carbon is 8300 Tg C. Ecological options to achieve this potential value are addressed. However, nutrient deficiency and seasonal water supply are serious drawbacks to take into account for increasing carbon accretion. These results are particular for the Orinoco llanos, even though described processes could be similar to world-wide savannas, where a gradient of carbon heterogeneity exists. 相似文献
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