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61.
Background: Coagulation disorders are frequently diagnosed, especially in hospitalized equidae, and result in increased morbidity and mortality. However, hemostatic reference intervals have not been established for donkeys yet. Objectives: To determine whether the most common coagulation parameters used in equine practice are different between healthy donkeys and horses. Animals: Thirty‐eight healthy donkeys and 29 healthy horses. Methods: Blood samples were collected to assess both coagulation and fibrinolytic systems by determination of platelet count, fibrinogen concentration, clotting times (prothrombin time [PT] and activated partial thromboplastin time [aPTT]), fibrin degradation products (FDP) and D‐Dimer concentrations. Results: PT and aPTT in donkeys were significantly (P < .05) shorter than those of horses. In contrast, FDP and D‐Dimer concentrations were significantly (P < .05) higher in donkeys than in horses. Conclusions and Clinical Importance: The coagulation parameters most commonly determined in equine practice are different in donkeys compared with horses. Thus, the use of normal reference ranges reported previously for healthy horses in donkeys might lead to a misdiagnosis of coagulopathy in healthy donkeys, and unnecessary treatments in sick donkeys. This is the first report of normal coagulation profile results in donkeys, and further studies are warranted to elucidate the physiological mechanisms of the differences observed between donkeys and horses.  相似文献   
62.
Four cases of equine bone lesions caused by Pythium insidiosum   总被引:4,自引:0,他引:4  
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63.
The incubation of swine peripheral blood mononuclear cells (PBMC) with African swine fever (ASF) virus preparations strongly inhibited the proliferative response of lymphocytes to PHA and other lectins. The inhibition, which persisted after inactivation of the virus by UV radiation, was dependent upon the dose and the time that virus preparations were present in cultures. When virus preparations were fractionated by ultracentrifugation, the inhibitory activity resulted to be soluble, whereas no activity was found in the sedimented viral fraction. However, the preincubation during 4 days of this sedimented fraction with swine PBMC, before the addition of the mitogen, restored the inhibitory activity. The results obtained suggest that the inhibition is mediated by one or more soluble factors released by swine PBMC after coincubation with ASF virus in a time dependent process. These factors show a molecular weight between 40 and 80 kDa by gel filtration chromatography. The inhibitory activity described in the present paper is an indication of inhibition of lymphocyte function produced by ASF virus which can help to understand how this virus escapes from the host immune system.  相似文献   
64.
65.

The impact of volcanic eruptions on humans and infrastructure has been significant and widely documented. However, the impact on forests covered by ash or tephra has not been as widely known or documented. This research evaluated the ashfall effects of the 1943–1952 Parícutin eruption on the radial growth of trees located near the top and flanks of the Tancítaro stratovolcano, ca.10 km southwest of the Parícutin volcano. We carried a dendrochronological sampling out in a temperate forest dominated by Pinus hartwegii and Abies religiosa trees. A ring-width chronology was built with 68 increment cores from 47 trees showed two statistically significant suppression events. The first event occurred from 1943 to 1946; it was caused by falling ash of the eruptive columns from Parícutin during the first 6 months of its eruption (February–June 1943). The second event occurred from 1818 to 1823, and it is attributed to the 1818 eruption of Volcán de Colima. The 1943–1946 suppression event observed in the tree rings demonstrates that trees are useful as palaeoenvironmental archives to evaluate the influence of volcanic eruptions in recent centuries in the Trans-Mexican Volcanic Belt. Our results indicate that falling ash immediately impacted the growth of trees in intertropical mountain zones of the Michoacan state located in the Michoacán-Guanajuato Volcanic Field. Such impact means that future eruptions may cause damage to crops and trees at the local and regional levels. Our findings contribute to evaluating volcanic hazards and risks in areas with active volcanoes and monogenetic volcanic fields.

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66.
The Totonac homegarden is a traditionally designed agroecosystem mixing different elements, such as cultivated and wild plants, and livestock. Our objective was to understand the role and importance of homegardens as a strategy for subsistence and natural resources management. Anthropological fieldwork was carried out in Coxquihui, Veracruz, Mexico, a Totonac community. Conventional sampling using a questionnaire yielded a sample of 40 individuals, each representing a family group. Personal interviews, life stories, observations, and field transects enriched survey information. Fieldwork permitted identification of four types of Totonac homegardens: backyards, cropping fields, acahuales or fallow fields, and fences or field edges. Each of these gardens yields an array of products and services important for several cultural roles and natural resource management aims. Totonacs see land as the dominant and most critical resource. A great deal of terrain is steeply sloped and soils are poor. Homegardens play a key role in a production system that minimizes these site limitations, striking a balance between resource maintenance and subsistence needs. Their functions are ecological, to foster a multistrata vegetation cover, and a continuous supply of organic matter to the soil; economic, serving as living storehouses where diverse products (food, timber, firewood, forage, animals, ceremonial supplies, medicinal products), are kept through the annual cycle; and social, performing various social roles such as growing medicinal, ritual, and edible plants, thus supporting beliefs and culture continuity. Studies like this contribute to a better understanding of Totonac culture and native ecology, and give ideas for a better land management.  相似文献   
67.
Genetic variances were estimated for a population ofSolarium tuberosum L. subsp.andigena, selected for adaptation to north temperate climatic conditions. Estimates for 15 traits, including some unique to true seed (TPS) propagation, were obtained from trials conducted under short day conditions in Peru. Only non-additive variance was found for yield, but heritability estimates were relatively high for tuber number and tuber size. The results indicated that yield could be increased through selection utilizing additive variance for the component traits, especially tuber size. Estimates of genetic variability for tuber uniformity were low. TPS yield was positively correlated with most other traits except tuber number.  相似文献   
68.
Summary Nine 2x clones with different genetic backgrounds and 2n pollen production by first division restitution (FDR) were each mated with five 4x females in a linextester design. Estimates of both general combining ability (GCA) and specific combining ability (SCA) were significant for tuber yield, among female and male parents. Four FDR clones with similar genetic background (half-sibs) showed significantly different GCA for total yield, illustrating the importance of progeny testing for FDR clones before their utilization as progenitors. A stronger influence of the 2x parents, compared to that of the 4x parents, on the performance of the hybrids was observed for characters studied. The significance of male and female interactions for characters other than tuber yield reinforced the importance of careful choice of the male and female parents for improving horticultural traits of 4x–2x progenies.  相似文献   
69.
Four different sets of true potato seed (TPS) families, representing a total of 262 hybrids derived from intermating tetraploid clones were evaluated in three different locations in Peru. Significant differences were observed among families in tuber yield, uniformity and transplant survival rate in the field. Several families produced an average tuber yield of more than 1.0 kg per plant, with a tuber uniformity of some families approaching that of standard varieties. Hybrid TPS families gave higher tuber yields and more uniform tubers than families from open-pollination. On the basis of an observed family-environment interaction for tuber yield, it is suggested that locally adapted cultivars or advanced selections should be used as parents to generate TPS progenies for specific areas.  相似文献   
70.
The relative effectiveness of phosphorus (P) applications on growth and the effect of added P on the extent of infection of roots of narrowleaf birsfoot trefoil (Lotus tenuis) and of broadleaf birdsfoot trefoil (Lotus corniculatus) by an indigenous VAM fungi (Glomus sp.) was studied on a P‐deficient soil (Typic Natraquoll). In terms of rate of increase of shoot growth per unit of added P, broadleaf was more efficient than narrowleaf birsdfoot trefoil but they did not differ in the relative effectiveness of P for growth. For the two Lotus species, when increasing the level of added P there was an initial increase in the percentage of root length infected, and then with further additions, there was a consistent decrease of the infection. For narrowleaf, the maximum percentage of root length infected was when plants reached 11% of their maximum shoot growth. Whereas for broafleaf, the maximum percentage of root infected was when plants reached the 66% of their maximum shoot growth. Despite differences in both, the shape of the response curve of shoot growth to P and the extent of infection between Lotus species, they did not differ in their ability to utilize the P that had reacted with the soil for a period of time.  相似文献   
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