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Recently, a new fungal disease caused by Diaporthe angelicae (anamorph Phomopsis foeniculi) has been found with increasingly frequency on fennel (Foeniculum vulgare) in Bulgaria. Using a bioassay-guided isolation and purification procedure, different metabolites were isolated from the fungal culture filtrates. They were identified by spectroscopic methods as nectriapyrone, a pentaketide monoterpenoid, and altersolanols A and J and macrosporin, three octaketides anthracenones. Leaf puncture bioassay was applied on detached tomato leaves to prove the phytotoxic activity of the fractions and of pure compounds. Nectriapyrone and altersolanols A and J showed a modulated phytotoxicity, while macrosporin was not toxic. Altersolanol A was the most active compound.  相似文献   
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The distribution of oestrogen and progesterone receptors in the equine genital tract was investigated by means of a modified dextran-coated charcoal method on samples collected from the vagina, the cervix and the uterus of 30 healthy adult Polish mares, divided into two groups on the basis of their serum progesterone levels. The concentrations of oestrogen and progesterone receptors were significantly (P<0·05) lower in the vagina and the cervix than in the uterus, in agreement with data from human beings, cattle and pigs, which showed that the highest concentrations of oestrogen and progesterone receptors were localised respectively in the body and in the horns of the uterus.  相似文献   
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Objectives

We examined canopy gap structure and regeneration patterns at the landscape scale using a combination of remote sensing and field-based surveys.

Methods

The study was carried out in the forest reserve of Lom, an old-growth Fagus-Abies-Picea forest located within the Dinaric Alps in the north-western part of Bosnia and Herzegovina. A high-resolution (1-m panchromatic and 4-m multispectral) Kompsat-2 satellite image was orthorectified and classified through an unsupervised pixel-based classification using an artificial neural network method.

Results

This approach allowed the identification of 650 canopy gaps, ranging in size from 32 to 1,776?m2. Only 20 intermediate to large gaps (>250?m2) were identified, and they were mainly present near the perimeter of the reserve. The origin of these large openings was associated with past human-caused disturbances or topographic conditions. The species composition of regeneration within large, human-caused gaps differed markedly from small gaps and non-gap sites in the core area of the reserve. Shade-intolerant species dominated the seedling and sapling layers in large openings. The landscape approach employed in this study confirmed the hypothesis that small gaps predominate at Lom, especially within the core area of the reserve.  相似文献   
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Visceral leishmaniasis in captive wild canids in Brazil   总被引:1,自引:1,他引:0  
Visceral leishmaniasis (VL) is endemic in Belo Horizonte (State of Minas Gerais, Brazil). Leishmania sp. can naturally infect several species of mammals, and the domestic dog is the most important reservoir of the disease in South America. This report describes five cases of visceral leishmaniasis in Brazilian canids. Among 15 animals kept in captivity in a zoo in Belo Horizonte (State of Minas Gerais, Brazil), two animals, a bush dog (Spheotos venaticos) and a hoary zorro (Lycalopex vetulus) were serologically positive and developed clinical signs of VL, whereas three other canids, including a crab-eating fox (Cerdocyon thous), a maned wolf (Chrysocyon brachyurus), and a hoary zorro (Lycalopex vetulus) had positive serological results without clinical signs.  相似文献   
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Background: The stomach is an underestimated key interface between the ingesta and the digestive system, affecting the digestion and playing an important role in several endocrine functions. The quality of starter microbiota and the early life feeding of medium chain triglycerides may affect porcine gastric maturation. Two trials(T1, T2) were carried out on 12 and 24 cesarean-delivered piglets(birth, d0), divided over two microbiota treatments, but slaughtered and sampled at two or three weeks of age, respectively. All piglets were fed orally: sow serum(T1) or pasteurized sow colostrum(T2) on d0; simple starter microbiota(Lactobacillus amylovorus, Clostridium glycolicum and Parabacteroides spp.)(d1-d3); complex microbiota inoculum(sow diluted feces, CA) or a placebo(simple association, SA)(d3-d4) and milk replacer ad libitum(d0-d4). The The T1 piglets and half of the T2 piglets were then fed a moist diet(CTRL); the remaining half of the T2 piglets were fed the CTRL diet fortified with medium chain triglycerides and 7% coconut oil(MCT). Total m RNA from the oxyntic mucosa was analyzed using Affymetrix?Porcine Gene array strips. Exploratory functional analysis of the resulting values was carried out using Gene Set Enrichment Analysis.Results: Complex microbiota upregulated 11 gene sets in piglets of each age group vs. SA. Of these sets, 6 were upregulated at both ages, including the set of gene markers of oxyntic mucosa. In comparison with the piglets receiving SA, the CA enriched the genes in the sets related to interferon response when the CTRL diet was given while the same sets were impoverished by CA with the MCT diet.Conclusions: Early colonization with a complex starter microbiota promoted the functional maturation of the oxyntic mucosa in an age-dependent manner. The dietary fatty acid source may have affected the recruitment and the maturation of the immune cells, particularly when the piglets were early associated with a simplified starter microbiota.  相似文献   
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The aim of this placebo-controlled study was to investigate the effects of oral vitamin E supplementation for 10 weeks on exercise-induced oxidative damage in untrained dogs. Eight dogs were randomly assigned to a supplementation (n = 4) or control (n = 4) group and underwent two isolated submaximal exercise sessions, 10 weeks apart. Blood was collected during each session to measure erythrocyte membrane fluidity (EMF), paraoxonase-1 (PON1) activity, plasma malondialdehyde (MDA) and vitamin E concentrations. These biomarkers were measured in venous blood samples collected before (t0), just after (t, EMF only) and 1 d (t + 1 d) and 7 d (t + 7 d) after the dogs ran on a treadmill.Prior to vitamin E supplementation, exercise induced a significant decrease in PON1 activity, EMF, vitamin E concentration and a significant increase in MDA concentration at t + 1 d. After a 10 week vitamin E supplementation period, these exercise-induced changes in PON1 activity, EMF and MDA concentration were still significant in the control group, but not in the supplemented group. These results suggested that vitamin E supplementation had a protective effect on submaximal exercise-induced oxidative damage in sedentary dogs.  相似文献   
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