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Nel Natalie Pietersen Gert Read David Alan Pietersen Gerhard 《European journal of plant pathology / European Foundation for Plant Pathology》2021,160(3):623-635
European Journal of Plant Pathology - The recent introduction of maize chlorotic mottle virus (MCMV) and spread of the resulting maize lethal necrosis disease (MLN) in East Africa presents a threat... 相似文献
343.
Thomas Flegel Marie-Kerstin Müller Katrin Truar Carina L?ffler Gerhard Oechtering 《The Canadian veterinary journal. La revue veterinaire canadienne》2013,54(10):969-973
Clinical features, myelography, and computed tomography imaging findings as well as neurological outcome with and without surgery in 5 pug dogs with thoracolumbar arachnoid diverticula are described. Short-term prognosis after surgical therapy may not be as good as reported for other canine breeds, since immediate postsurgical deterioration is possible. Improvement of neurological deficits beyond the presurgical status may take several months. 相似文献
344.
The morphology and histology of the digestive tract of the branchiuran crustacean, Chonopeltis australis Box shall, 1976 are described from serial sections. The foregut is differentiated into a preoral cavity, containing the mandibles and tongue, an ascending oesophagus, with an H-shaped lumen invested with longitudinal, circular and dilator muscles, a horizontal oesophagus with a star-shaped lumen and lacking longitudinal and dilator muscles, and an oesophageal funnel consisting of inner and recurrent walls. The midgut is differentiated into anterior and posterior chambers, separated by an S-shaped muscular tube. The arborescent midgut glands open laterally into the anterior part of the anterior midgut. Columnar epithelial cells line the anterior midgut whereas tall, papilliform cells are present in the epithelium of the posterior midgut. The transition from posterior midgut to hindgut is marked by the presence of very tall epithelial cells. The terminology describing the various parts of the digestive tract of branchiurans is discussed. 相似文献
345.
Felipe Rossetti de Paula Pedro Gerhard Seth J. Wenger Anderson Ferreira Carlos Alberto Vettorazzi Silvio Frosini de Barros Ferraz 《Landscape Ecology》2013,28(1):13-27
Large wood (LW) is critical to the structure and function of streams and forests are the main LW source to stream channels. To assess the influence of forest cover changes at different spatial scales on in-stream LW quantity, we selected eighteen catchments (2nd–4th order) in Southeastern Brazil with forests at different levels of alterations. In each catchment we quantified the pattern of forest cover (% cover and relative catchment position), the physical characteristics of catchments (elevation and slope), the characteristics of channels (wetted channel width and depth), the abundance and volume of in-stream LW, and the frequency of LW pools. We used simple and multiple linear regression to assess the response of LW variables to landscape and stream reach variables. Most of the LW was relatively small; 72 % had a diameter <20 cm, and 66 % had a length <5 m. Although percent forest cover at reach scale had substantial support to explain LW variables, the best predictors of LW variables were forest cover at broader scales (LW abundance and LW pool frequency were best predicted by forest at intermediate distance at the catchment scale and LW volume was best predicted by forest cover at the drainage network scale), suggesting that downstream transport is an important process in addition to local processes in our study area. These findings have important management implications because although low forested reaches receive less LW from local forests (or no LW in the case of deforested stream reaches), they are receiving LW from upstream forested reaches. However, the material is generally small, unstable and likely to be easily flushed. This suggests that not only should riparian forest conservation encompass the full drainage network, but forests should also be allowed to regenerate to later successional stages to provide larger, higher quality LW for natural structuring of streams. 相似文献
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E Leidinger G Loupal R Gutleb I Miller R Chizzola 《DTW. Deutsche tier?rztliche Wochenschrift》1992,99(8):332-335
Six rabbits were immunized against the pyrrolizidine alkaloid retrorsin, conjugated to bovine serum albumin. Seven i.v. inoculations were distributed over a period of half a year. The total antigen dose differed between animals. Towards the end of the experiment all animals (except 2 receiving the lowest antigen dose) suffered from apathy, anorexia and loss of body weight. Pathologically these symptoms correlated well with liver cirrhosis, gradually dependent on the total antigen dose. Blood-chemical parameters were disparate and contradictory. 相似文献
349.
In order to investigate the fine structure of the chicken's Bulbus olfactorius and to determine differences between birds and mammals, tissue specimen were taken from 26 animals. The following techniques were used: Luxol-Fast-Blue- and Nisslstaining, Bodian impregnation. Marked differences between the Bulbus of chicken and mammals were found lightmicroscopically in the number of the cell layers and the localization and size of cells. The electronmicroscope revealed that the cell organelles and the different types of synapses resembled the ones found in mammals. The mitral cells of the hen contrary to the ones of mammals often contained lamellar bodies. 相似文献
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