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101.
The presence of parasites was investigated by the examination of 1944 dog faecal samples collected from urban (n = 646) and rural (n = 1298) areas of the province of Neuquén, Patagonia, Argentina. Parasitic agents (PA) were found in 37.86% of samples. A total of 15 different PA were detected, including Toxocara canis (16.35%), Taenia spp./Echinococcus spp. (12.65%), Trichurisvulpis (6.06%), Giardia spp. (1.29%), Toxascaris leonina (0.56%), Ancylostomacaninum (0.41%), Dipylidium caninum (0.31%), Diphyllobothrium spp. (0.10%), among others. Several of these PA are recognized as zoonotic agents. Therefore, the results of this investigation revealed that local population is exposed to a broad spectrum of zoonotic parasites by means of environmental contamination with dog faeces. Prevalence of PA was slightly higher in rural (40.06%) than in urban (33.44%) locations. Distribution of groups of PA (cestodes, nematodes, and protozoa) showed statistical differences between both habitats. Prevalence of cestodes (18.18%) and protozoa (11.86%) was significantly higher in the rural environment than in urban areas and nematodes (29.10%) were more frequent in urban locations. Infection of dogs with Linguatula serrata and Cryptosporidium sp. was demonstrated for the first time in Neuquén. Rural dogs of the study area are under hydatic disease control program, which includes treatment with praziquantel every 6 weeks; thus, the finding of high level of cestode infection in these areas is of great relevance. The epidemiology of zoonotic parasitic infections in urban and rural dogs showed different patterns and, in consequence, different control measurements should be applied in each location.  相似文献   
102.
A fatty acid-binding protein (FABP) from the liver of Argentine hake (Merluccius hubbsi) was isolated and characterized and its expression analyzed. The determination of its partial primary structures (72 %) showed that it presents highest identity with Fabp10, commonly termed liver basic-type FABP. The evolutionary tree showed greater relationship between the Fabp10 of hake (Me Fabp10) and the Fabp10 and the Fabp10a of teleost fish. Me Fabp10 had low affinity for palmitic, oleic and palmitoleic acid and high affinity for bilirubin, lysophosphatidylcholine and lysophosphatidylethanolamine, all of them important in the metabolic functions of the liver. Me Fabp10 was able to bind only one cis-parinaric acid molecule and was found to be expressed only in the liver.  相似文献   
103.
Efficient selection of potato varieties with enhanced nutritional quality requires simple, rapid, accurate, and cost-effective assays to obtain tuber chemical composition information. Our objective was to develop simple protocols to determine phenolics, anthocyanins, and antioxidant capacity in polyphenolic extracts of potatoes using Fourier transform infrared spectroscopy combined with multivariate techniques. Lyophilized potato samples (23) were analyzed. Polyphenolic compounds were extracted from potatoes and applied directly applied onto a three-bounce ZnSe crystal for attenuated total reflectance measurements in the infrared region of 4000 to 700 cm (-1). Robust models were generated (r > or = 0.99) with standard error of cross-validation values of 4.17 mg gallic acid equivalent/100 g (total phenolics), 0.87 mg pelargonidin-3-glucoside/100 g (monomeric anthocyanins), and 130.8 mumol Trolox equivalent/100 g (antioxidant capacity) potato powder. In addition, classification models discriminated potato samples at the species and variety level. Application of a simple infrared spectroscopic protocol allowed simultaneous rapid quantification of specific nutritional components in potatoes and efficient selection of value-added potato varieties.  相似文献   
104.
A medico-ethnobotanical study was conducted among the Tabarkin communities living in Calasetta and Carloforte, in south-western Sardinia. These communities represent a Ligurian minority who have resided in Sardinia since their forebears migrated from Tabarka in Tunisia in the second half of the 18th Century, having previously migrated to Tabarka from Genoa in 1544. In this study, we conducted more than 200 interviews and recorded 53 botanical taxa and 72 folk pharmaceutical preparations, which represent the folk medicine of the Tabarkins. The folk phytotherapy of the Tabarkins living in Calasetta and Carloforte is quite restricted compared with other folk phytotherapy recorded in similar recent ethnobotanical studies conducted in Sardinia. This could indicate that there has been a remarkable erosion of Traditional Knowledge (TK) within these two communities. Of particular interest are a few local medical uses we recorded that have never or only very rarely been documented in Italy; namely the use of Dittrichia graveolens (L.) Greuter as an anti-haemorrhoidal, of Centaurea calcitrapa L. as a remedy for malaria, of Glycyrrhiza glabra L. in ophthalmic treatments, and of Urtica dioica L. as an antiviral in cases of German measles. Most of the botanical species quoted in this research are referred to in the two centres using a local Ligurian idiom. Most of the medico-botanical uses we recorded are very similar to those collected in other ethnobotanical surveys carried out in Liguria and south-western Sardinia. Because there was no evidence in this research of any substantial ethnobotanical traces related to the communities’ North-African experience, it would appear that the Tabarkins have readily adopted their host culture’s use of medicinal plants and have retained their own traditional cognitive concepts and knowledge of the natural plant world through the language only.  相似文献   
105.
In the 1950s, a long-term experiment was initiated at three locations in Northern Sweden. The treatments included four cropping systems, which differed in the number of years with leys or annual crops in the crop rotation. To create awareness of the experiment as a research resource for further scientific studies, we summarise the history (experimental design, materials and methods, main measurements) and scientific findings of the experiment, as well as reflect on its usefulness and opportunities for further studies. So far, scientific focus has been on the effects of cropping systems on soil characteristics. The main findings indicate that soil porosity and hydraulic conductivity were greater in cropping systems with a large proportion of ley, soil bulk density showed the opposite trend. In terms of chemical properties, cropping systems incorporating more ley also have greater soil organic carbon content than annual crops systems, and both soil carbon and N storage decrease over time in cropping systems with only annual crops. The effects of cropping system on crop yields and quality are areas for further investigation.  相似文献   
106.
The influence of manure and diammonium phosphate (DAP) mineral fertilizer on germination, leaf nitrogen content, nitrate accumulation and yield of vegetable amaranth (Amaranthus hypochondriacus) was investigated. Field trials were set up at the University of Nairobi Field Station at the Upper Kabete Campus during the long rains of March–May in 2007 and 2008. Trials were laid out as complete randomized block design with four fertilization treatments: 20, 40, and 60 kg nitrogen (N) ha?1 supplied by DAP (18:46:0), 40 kg N ha?1 supplied by cattle manure and an unfertilized control variant. The vegetables were harvested at three maturity stages at 6, 7, and 8 weeks after planting. Results indicated that there were significant differences between treatments in germination percentage, leaf nitrogen content, nitrate accumulation and vegetable yield. Plants that received manure had a higher germination percentage than those that received the same amount of N supplied by the chemical fertilizer DAP. The yields generally increased from week 6 to week 8. The highest yield was recorded in plots receiving 40 kg N ha?1 from DAP at eight weeks after planting. Plots that were supplied with manure recorded the lowest yield when compared to the fertilizer treated plots at all rates. Leaf nitrogen content increased with increasing rate of N but only when N was supplied by DAP fertilizer. The leaf nitrogen content decreased with increasing age of the plants. The leaf nitrate content increased with increase in DAP application rate. Results indicate that manure application produced quality vegetables in terms of low nitrate levels, but leaf nitrogen and vegetable yields were low. DAP application effected higher yields, but the vegetables had high though acceptable nitrate levels.  相似文献   
107.
The effects of 18 essential oils, yeast, Quebracho tannin and Quillaja saponin on ruminal methane and gas production (GP) were studied in vitro. A lactating cow diet was incubated with rumen inoculum. Doses of the additives (mg/L) were: essential oils = 500; tannin = 67; yeast = 8.35 and 16.7; and saponin = 300. Lemongrass, estragole, eugenol, geraniol, limonen, thyme oil and thymol produced less gas (overall mean 33.8 mL/200 mg dry matter (DM)) than control (43.6 mL/200 mg DM; P < 0.001). Methane produced (mL/200 mg DM) by guaiacol (10.7), lemongrass (9.6), limonene (11.4), thyme oil (10.9) and thymol (2.1) was lower than control (12.5) (P < 0.001). Methane percentage on total GP was lower (P < 0.001) for cinnamic alcohol (25.4), guaiacol (24.5), thymol (19.7) and vanillin (26.3) than control (28.8). In a second experiment, thymol, guaiacol and yeast were added to the diet of dry fistulated cows to determine in situ neutral detergent fiber digestibility (NDFD) of six forages and in vivo dietary NDFD. Thymol and yeast decreased in situ NDFD after 24 h (33.9% and 33.5% vs. 38.1%; P = 0.008). Thymol decreased in vivo total tract NDFD (40.8% vs. 51.4%; P = 0.02). Differences in GP and methane levels were registered within classes of additives. A careful selection of additives may allow for the manipulation of ruminal fermentation.  相似文献   
108.
UV radiation leads to the generation of reactive oxygen species (ROS). These molecules exert a variety of harmful effects by altering key cellular functions and may result in cell death. Several studies have demonstrated that human skin can be protected against UV radiation by using plant-derived antioxidants. Here we evaluated the in vitro capacity of several antioxidant polyphenolic fractions from grape, which differ in their degree of polymerization and percentage of galloylation, to protect HaCaT human keratinocytes against UV-induced oxidative damage. These fractions inhibited both basal and UVB- or UVA-induced intracellular ROS generation in this cell line. Consequently, the same fractions inhibited p38 and JNK1/2 activation induced by UVB or UVA radiation. The highest protective effect was for fractions rich in procyanidin oligomers and gallate esters. These encouraging in vitro results support further research and should be taken into consideration into the clinical pharmacology of plant-derived polyphenolic extracts as novel agents for skin photoprotection.  相似文献   
109.
A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl–Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans.  相似文献   
110.
This study evaluated the effects of globin and spray-dried porcine plasma (SDPP) on growth performance, digestibility, nitrogen retention, energy retention efficiency (ERE) and intestinal morphology of broiler chickens. A total of 336-day-old male broiler chickens were reared from 1 to 40 days of age and fed 3 diets (8 replicates/diet, 14 birds/replicate) during 3 feeding phases: starter (1–12 days), grower (12–25 days) and finisher (25–40 days). Isonitrogenous diets were formulated by replacing gluten protein isolate contained in the control diet (C diet) with 2% (starter) or 1% (grower and finisher) spray-dried porcine plasma in the plasma diet (SDPP diet). The globin diet (G diet) was obtained by adding globin on the top of C diet at a dose of 0.08% for the whole rearing period. Total tract apparent digestibility (aD), nitrogen retention and ERE were assessed during the three growing phases. At 12  and 40 days of age, one bird per pen was slaughtered to sample gut, liver, spleen and bursa of Fabricius for histomorphological investigations. The SDPP diet increased body weights of chickens at 12 (+60 g; p < .001), 25 (+101 g; p < .001) and 40 days (+130 g; p = .018) of age compared to C and G diets. Also SDPP improved crude protein aD (+9.7%) and ERE (+12.3%) during the starter phase (p < .001). Dietary globin and SDPP inclusion did not affect either the gut morphology or the histopathological findings in birds at 12 and 40 days of age, despite a numerical (+6.90% and +7.40% respectively) villus height improvement in the SDPP group. Overall, these results confirm that dietary supplementation with SDPP and, to a lesser extent, with globin can improve growth performance and dietary protein and energy utilization in broiler chickens without effect on gut functionality.  相似文献   
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