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排序方式: 共有237条查询结果,搜索用时 15 毫秒
11.
Christian Walzer Anna Kübber-Heiss Nadia Robert 《Journal of veterinary diagnostic investigation》2002,14(1):76-79
Removal of the spinal cord is considered time consuming and difficult. A delay in the necropsy procedure, especially in the central nervous system, can result in significant tissue autolysis and subsequent diagnostic difficulties. In the field, where many necropsies are performed, suitable electric saws are mostly unavailable. A technically simple and rapid method for spinal cord removal, requiring only a straightforward tool, has been devised. No necropsy-induced structural damage has been noted on histopathologic examination. 相似文献
12.
Acral mutilation and analgesia (AMA) is reported in 13 French spaniels in Canada. This newly recognized disorder shares striking similarities in clinical features and biopsy findings to the other acral mutilation syndromes or hereditary sensory neuropathies reported in German short-haired pointer dogs, English pointer dogs and English springer spaniels. Clinical signs are first noted between 3.5 and 12 months of age. Affected dogs lick, bite and severely self-mutilate their distal extremities resulting in ulcers with secondary bacterial infection. Auto-amputation of claws, digits and footpads occurs in severe cases. Single or multiple feet can be affected. Affected dogs walked on their severely mutilated feet without evidence of pain, lameness, or ataxia. The majority of the dogs were euthanized within days to months of diagnosis. 相似文献
13.
Olivieri A Achilli A Pala M Battaglia V Fornarino S Al-Zahery N Scozzari R Cruciani F Behar DM Dugoujon JM Coudray C Santachiara-Benerecetti AS Semino O Bandelt HJ Torroni A 《Science (New York, N.Y.)》2006,314(5806):1767-1770
Sequencing of 81 entire human mitochondrial DNAs (mtDNAs) belonging to haplogroups M1 and U6 reveals that these predominantly North African clades arose in southwestern Asia and moved together to Africa about 40,000 to 45,000 years ago. Their arrival temporally overlaps with the event(s) that led to the peopling of Europe by modern humans and was most likely the result of the same change in climate conditions that allowed humans to enter the Levant, opening the way to the colonization of both Europe and North Africa. Thus, the early Upper Palaeolithic population(s) carrying M1 and U6 did not return to Africa along the southern coastal route of the "out of Africa" exit, but from the Mediterranean area; and the North African Dabban and European Aurignacian industries derived from a common Levantine source. 相似文献
14.
Steven De Decker DVM PhD Emma Davies DVM Diplomate ECVN Livia Benigni DVM Diplomate ECVDI Helen Wilson BVSc Ludovic Pelligand DVM PhD Diplomate ECVAA Emma L. Rayner BSc BVetMed FRCPath MRCVS Nadia Shihab MA VetMB Diplomate ECVN Holger A. Volk DVM PhD Diplomate ECVN 《Veterinary surgery : VS》2012,41(6):766-771
15.
16.
Vesper HW Slimani N Hallmans G Tjønneland A Agudo A Benetou V Bingham S Boeing H Boutron-Ruault MC Bueno-de-Mesquita HB Chirlaque D Clavel-Chapelon F Crowe F Drogan D Ferrari P Johansson I Kaaks R Linseisen J Lund E Manjer J Mattiello A Palli D Peeters PH Rinaldi S Skeie G Trichopoulou A Vineis P Wirfält E Overvad K Strömberg U 《Journal of agricultural and food chemistry》2008,56(15):6046-6053
Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered. 相似文献
17.
Sandrine Salmon Nadia Artuso Lorenzo Frizzera Roberto Zampedri 《Soil biology & biochemistry》2008,40(7):1707-1715
This study investigated the responses of soil animal communities, soil functioning and humus forms to forest dynamics and solar radiation. We examined changes in invertebrate communities and soil features in two subalpine spruce forests (Eastern Italian Alps, Trento) growing on a calcareous bedrock, with different sun exposures (north and south), each forming a chronosequence of three developmental phases: clearing, regeneration stand (25-year-old trees) and mature stand (170-year-old trees). Our results indicate that the two forest sites differed in solar energy input, soil chemical properties and the relationships between forest dynamics and animal communities. In the north-facing site, soil fauna communities were very similar in the three forest developmental phases. Conversely, in the south-facing site, the composition of invertebrate communities and the diversity of zoological groups varied greatly among developmental phases. The highest abundance of total invertebrates, and mites in particular, occurred in the south-facing mature stands while the south-facing regeneration stand was characterised by higher densities of Collembola, Chilopoda, Symphyla, Protura and Aranea. The structure of communities in clearings was the same as in regeneration stands but with lower invertebrate abundance. Humus forms and soil features changed with developmental phases in both the south- and north-facing sites, although variations were more pronounced in the southern exposure. Mature stands were characterised by high levels of soil organic carbon and nitrogen, C/N values and low pH, the clearings and regeneration stands being characterised by a greater release of mineral nitrogen. The diversity of zoological groups (Shannon–Wiener index) was linearly correlated to soil pH, Humus Index, the amount of organic carbon and the species richness of herbaceous plants. Our results about the composition and the diversity of invertebrate communities are consistent with the observations of other authors studying south-exposed forests growing on different bedrock types, indicating that such relationships are widespread. The higher densities of invertebrates in the south-facing site may be attributed to higher solar radiation, and the positive correlation observed between total soil fauna abundance and solar energy supports the “more individuals” hypothesis that assumes a positive relationship between the number of individuals and energy availability. Possible ways by which forest dynamics control soil invertebrate communities are discussed. 相似文献
18.
Khaled Mguis Nadia Ben Brahim Ali Albouchi Mbarka Yakkoubi-Tej Asma Mahjoub Zeineb Ouerghi 《Genetic Resources and Crop Evolution》2008,55(5):665-674
In order to study the salt effect on the wild wheat and durum wheat, three accessions of Aegilops geniculata L. from Ain zana, Zaghouan, and Sbitla and one variety of wheat (Triticum durum L.) have been grown in the INRAT green house and treated with different salt concentrations. The morphological, phenological
and yield characters have been measured for each plant and analyzed using SAS software. This study has shown a high degree
of variation of these characters mainly related to geographical origin. It was observed also that Sbitla accession was less
affected by the imposed salt stress than all the others while Ain zana was the most affected one. 相似文献
19.
Boujenane Ismaïl El Khattaby Nadia Laghouaouta Houda Badaoui Bouabid Piro Mohammed 《Tropical animal health and production》2019,51(6):1367-1373
Tropical Animal Health and Production - Fourteen body measurements of 132 adult female camels belonging to three populations Guerzni (60), Khouari (28), and Marmouri (44) reared in 38 herds of 8... 相似文献
20.
Frank David Cdric Hubas Helne Laguerre Aicha Badou Gwen Herault Tho Bordelet Nadia Ameziane 《Aquaculture Nutrition》2020,26(5):1568-1583
Various research projects in Europe and North Africa have recently intended to breed temperate holothurians to alleviate fishing pressure on natural populations. However, to date little is known about the nutritional requirements of East Atlantic and Mediterranean species. In this study, we propose a “natural population”‐oriented approach to characterize food sources, digestive efficiency and resources allocation based on the composition of pigments and fatty acids (FA) in gut contents and tissues (muscles, gonads and digestive tract walls) of wild individuals of the species Holothuria (Panningothuria) forskali (Delle Chiaje, 1823) sampled in Brittany (France). Our study reveals that neither green nor red algae enter the diet of H. forskali in spring and that the only fresh vegetal material found in gut contents is brown algae (very likely diatoms). The high nutritional quality of gut contents however contrasts with the detrital nature of the ingested food sources, suggesting that a trophic upgrading of organic matter occurs before digestion. In addition, unusual FA (i.e. only present in a few groups of living species) such as long‐chain monounsaturated FA (especially the FA 23:1ω9) were found in large proportions in muscles and gonad and their effect on sea cucumber fitness needs further investigation. 相似文献