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51.
A prospective study was performed (November 1998 to December 2003) to determine the prevalence of systemic hypertension (SH) in dogs with glomerular disease secondary to leishmaniasis. One hundred and five dogs with leishmaniasis were screened and staged for the presence of renal disease (RD) and SH. For the purpose of the study, RD was defined as serum creatinine concentration > or = 1.4 mg/dL, a urine protein/creatinine ratio > or = 0.5, or both. SH was defined as a systolic blood pressure (SBP) > or =180 mm Hg or an SBP between 150 and 179 mm Hg in the presence of clinical manifestations of SH. Fifty-two (49.5%) of the dogs had some degree of RD, and 32 (61.5%) of these dogs were diagnosed with SH. Moreover, SH also was diagnosed in 3 dogs without RD. Left ventricular hypertrophy (LVH), estimated by echocardiography, was the most frequently observed systemic consequence of hypertension, being present in 32 (91.4%) of the hypertensive dogs. Echocardiographic abnormalities were not detected in any of the 33 dogs with leishmaniasis without RD, which were used as controls. Ocular consequences of SH were observed in only 2 (5.7%) of the dogs with hypertension. We conclude that SH is prevalent in dogs with RD secondary to leishmaniasis, not only in the more severe stages but also in the early course of the illness before azotemia becomes apparent. Canine leishmaniasis may be a useful natural model to study SH secondary to glomerular disease.  相似文献   
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Growth and survival of hatchery‐bred Asian catfish, Clarias macrocephalus (Günther), fry reared at different stocking densities in net cages suspended in tanks and ponds were measured. The stocking densities used were 285, 571 and 1143 fry m?3 in tanks and 114, 228 and 457 fry m?3 in ponds. Fish were fed a formulated diet throughout the 28‐day rearing period. Generally, fish reared in cages in ponds grew faster, with a specific growth rate (SGR) range of 10.3–14.6% day?1, than those in cages suspended in tanks (SGR range 9–11.3% day?1). This could be attributed to the presence of natural zooplankton (copepods and cladocerans) in the pond throughout the culture period, which served as additional food sources for catfish juveniles. In both scenarios, the fish reared at lower densities had significantly higher SGR than fish reared at higher densities. In the pond, the SGR of fish held at 228 and 457 m?3 were similar to each other but were significantly lower than those of fish held at 114 m?3. The zooplankton in ponds consisted mostly of copepods and cladocerans, in contrast to tanks, in which rotifers were more predominant. Per cent survival ranged from 85% to 89% in tanks and from 78% to 87% in ponds and did not differ significantly among stocking densities and between rearing systems. In conclusion, catfish nursery in cages suspended in tanks and ponds is density dependent. Catfish fry reared at 285 m?3 in tanks and at 114 m?3 in ponds had significantly faster growth rates than fish reared at higher densities. However, the desired fingerling size of 3–4 cm total length for stocking in grow‐out culture can still be attained at stocking densities of 457 m?3 in nursery pond and 571 m?3 in tanks.  相似文献   
53.
We hypothesized that the information obtained from a discriminant analysis could be used to objectively discriminate horses untrained from early ages, in agreement with certain physiological characteristics.In the biopsies of 24 Spanish Pure Bred horses (1.5–3 years old) before and after a standardized exercise test (SET; 4–7 m/s with a change of velocity of 1 m/s every 2 min) muscle enzymes, substrate and metabolites were determined. Also, diverse plasma and blood parameters were considered.Three pre-exercise groups (A1: six horses; A2: seven horses and A3: eleven horses) and two post-exercise groups (B1: sixteen horses; B2: eight horses) were defined from a correspondence analysis. Forward stepwise discriminant analysis selected 11 variables which differentiated the groups between each other both pre- and post-exercise.The results of the present study suggested the utility of a discriminant analysis to categorize horses in agreement with certain physiological variables. It could be used for establishing different types of training in each group by expert trainers.  相似文献   
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The development of postattenuation neurologic signs (PANS) is a poorly understood and potentially devastating complication after surgical attenuation of congenital portosystemic shunts in dogs. Postattenuation neurologic signs include seizures but also more subtle neurologic signs such as depression, behavioral changes, tremors, and twitching. They most commonly occur within 7 days postoperatively and are typically unrelated to hyperammonemia, hypoglycemia, or electrolyte disturbances. This narrative review summarizes the findings of 50 publications from 1988-2020 that report occurrence of PANS. While most published reports included only dogs affected by postattenuation seizures (PAS), others included dogs with any form of PANS. Overall, PANS (including PAS) affected 1.6%-27.3% of dogs, whereas incidence of PAS ranged from 0%-18.2%. The etiology of PANS remains unknown; however, several theories have been proposed. Risk factors include preoperative hepatic encephalopathy, increasing age, and possibly certain breeds and extrahepatic shunt morphology. There is increasing evidence that prophylactic antiepileptic drugs do not prevent PANS. Treatment is centered around controlling neurologic signs with antiepileptic drugs and providing supportive intensive care. The 30-day survival rate in studies that included a minimum of four dogs affected by PANS was 0%-100% (median, 50.0%) and 0%-75.0% (median, 37.5%) for those with PAS. Mortality associated with PANS was typically related to occurrence of generalized seizure activity. Prognostic factors positively associated with short-term survival included having a history of preoperative seizures and development of focal seizures only. If affected dogs survived to discharge, survival for several years was possible, and the majority of neurologic signs manifested as part of the phenomenon of PANS appeared to resolve.  相似文献   
56.
Dehesa agroforestry systems occupy around 6 million ha in the Iberian Peninsula. Their economic and environmental sustainability depends on the maintenance of the extensive livestock farms which created this typical ecosystem. This work analyzes dehesa farms in the Extremadura region (SW Spain) using technical and economic indicators of 69 randomly selected holdings. Principal component analysis (PCA) allowed us to establish a valid model explaining 65.8% of the variance. The two principal components having most weight were Iberian pig production (explaining 20% of the variance of the model), and which ruminant species were raised on the farm (15% of the variance). A cluster analysis distinguished five types of farms: sheep farms at high and low stocking rates, beef cattle farms, wooded farms with mixed livestock, and farms with a high level of cropping activity. The most profitable farms were those with either high overall livestock density or a high level of Iberian pig production. While high stocking density has historically attracted high levels of subsidy, production of Iberian pigs was profitable because of the high value of the product. In the light of CAP reform, Iberian pig production seems the most readily sustainable type of farming for the dehesa system.
F. J. MesíasEmail:
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ABSTRACT

The effect of two thermal photoselective polyethylene sheets with or without solar heat reflection pigments (SHRP) combined with two transplant types (grafted or un-grafted) were analyzed in sweet pepper plants. The selective transmittance through the photoselective sheet increased the temperature inside the greenhouse compared with the standard sheet. Plants grown under SHRP sheet significantly increased total leaves fresh weight and total fruit yield. When plants were grafted, leaf and stem fresh weight were reduced compared with the ungrafted plants, but total fruit number was increased. Leaf nitrate (NO3 ?) concentration was affected by both sheet and transplant type at early stage of crop development but not at later stages. Total-nitrogen (N) was found to be higher in grafted plants, but with a lower microelements concentration. Grafted plants had an increased the number of days to harvest at the second truss, reducing significantly its weight and size. But at the end of the crop cycle, these plants showed higher total marketable yield than the un-grafted plants. Plant grown under SHRP sheet showed higher yield than those plants under standard sheet. Results shows that new cultivation techniques such as use grafted plants and new thermal photoselective sheets should be take into account to increase yield of sweet pepper under semi-arid conditions.  相似文献   
59.
Many cytotoxic compounds of therapeutic interest have been isolated from marine invertebrates, and some of them have been reported to be of microbial origin. Pyridoacridine alkaloids are the main compounds extracted from the ascidian Cystodytes dellechiajei. Here we describe the in vitro antiproliferative activity against different tumor cell lines of the ascidian extracts and provide some insights on the role of the microbial community associated with the tunicate in the production of these compounds. C. dellechiajei extracts showed remarkably high antiproliferative activity (IC50 ≤5 μg/mL) in human lung carcinoma A-549, colon adenocarcinoma H-116, pancreatic adenocarcinoma PSN-1 and breast carcinoma SKBR3 cell lines. Moreover, we found that the maximum activity was located in the tunic tissue of the colony, which harbours a microbial community. In order to ascertain the involvement of this community in the synthesis of the bioactive compounds different approachs that included culture and culture independent methods were carried out. We undertook a screening for antiproliferative activities of the bacterial isolates from the ascidian, as well as a comprative analysis of the cytotoxic activities and the microbial communities from two color morphs of the ascidian, green and blue. In addition, the changes of the antiproliferative activities and the composition of the microbial communities were studied from ascidians kept in aquaria and treated with antibiotics for one month. Our data obtained from the different experiments did not point out to bacteria as the source of the cytotoxic compounds, suggesting thus an ascidian origin.  相似文献   
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