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排序方式: 共有133条查询结果,搜索用时 31 毫秒
61.
Lorenzo Maggioni Roland von Bothmer Gert Poulsen Elinor Lipman 《Genetic Resources and Crop Evolution》2018,65(1):137-159
The domestication process of Brassica oleracea L. has not been fully clarified, either regarding its initial location or the progenitor species involved. Two alternative hypotheses proposed so far point to either a northwest European or a Mediterranean location. Previous studies to clarify the domestication process focused on linguistic aspects and on the earliest occurrences in ancient literature of words referring to B. oleracea. Those studies are here extended to offer a comprehensive account of literary occurrences of the brassica vegetables in ancient Greek and Latin texts, between the VI century B.C.E. and the IV century C.E. This study offers a contribution to ancient ethnobotanical knowledge in the Mediterranean, including agricultural practices and culinary and medicinal uses. It also defines the time when increasing diversity of crop varieties is documented and it adds weight to the hypothesis of a Mediterranean location of the domestication of B. oleracea. 相似文献
62.
Nigussie Haregeweyn Jean Poesen Jan Nyssen Gerard Govers Gert Verstraeten Joris de Vente Jozef Deckers Jan Moeyersons Mitiku Haile 《CATENA》2008
In Tigray-northern Ethiopia, lack of sediment yield data and appropriate methodologies for predicting sediment yield have contributed to poor planning resulting in rapid sedimentation in reservoirs and storage capacity loss. The objectives of this study were: (1) to assess the spatial variability of absolute sediment yield (SY) and area-specific sediment yield (SSY) and to identify their controlling factors for 11 representative catchments and (2) to develop models to predict sediment yield. We quantified sediment yield from reservoir sediment surveys and studied the role of bio-physical characteristics of the catchments and their interactions in controlling SY and SSY variability. 相似文献
63.
Gert Hoffmann 《Journal of pest science》1953,26(10):153-154
Ohne Zusammenfassung 相似文献
64.
John N. Wairore Stephen M. Mureithi Oliver V. Wasonga Gert Nyberg 《Land Degradation \u0026amp; Development》2016,27(3):532-541
Rehabilitating degraded rangelands using enclosures offers various benefits to agro‐pastoral households. However, enclosure benefits cannot be generalized as there are variations across dryland ecosystems and societies. This study assessed the qualitative and quantitative benefits derived from rehabilitating degraded rangelands using private enclosures in Chepareria, West Pokot County, Kenya. Dry‐season grazing reserves, healthier livestock, improved livestock productivity, easier livestock management, food security, reduced animal losses, ecosystem services, land ownership, independence and improved standard of living were the main qualitative benefits from private enclosures identified. Quantitative benefits were manifested through various enclosure enterprise combinations, sale of enclosure marketable products and adoption of alternative income generating activities. They included the sale of livestock and livestock products, maize, wood cutting, grass cuttings, contractual grazing, grass seeds, poultry products, fruits and honey, amongst others. Livestock production directly accounts for 42·4% of the total enclosure income and is the main source of livelihood in Chepareria. There was a significant trend of increasing total enclosure income with enclosure acreage (p ≤ 0·05) while enclosure age was insignificant. Enclosures cushion households against climatic shocks such as drought by providing additional flexibility in land, fodder, livestock management and the uptake of various income generating activities. We conclude that enclosures have the potential of contributing to resilience as attested from the benefits reported in this study. However, private enclosure tradeoffs such income differentiation, reduced communal land and conflict have implications on how the ecological and socio‐economic aspects may be impacted as the establishment of private enclosures in Chepareria continues. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
65.
van Dam KG van Breda E Schaart G van Ginneken MM Wijnberg ID de Graaf-Roelfsema E van der Kolk JH Keizer HA 《American journal of veterinary research》2004,65(7):951-956
OBJECTIVE: To investigate the expression and localization of glucose transporter 4 (GLUT4) and fatty acid translocase (FAT/CD36) in equine skeletal muscle. SAMPLE POPULATION: Muscle biopsy specimens obtained from 5 healthy Dutch Warmblood horses. PROCEDURES: Percutaneous biopsy specimens were obtained from the vastus lateralis, pectoralis descendens, and triceps brachii muscles. Cryosections were stained with combinations of GLUT4 and myosin heavy chain (MHC) specific antibodies or FAT/CD36 and MHC antibodies to assess the fiber specific expression of GLUT4 and FAT/CD36 in equine skeletal muscle via indirect immunofluorescent microscopy. RESULTS: Immunofluorescent staining revealed that GLUT4 was predominantly expressed in the cytosol of fast type 2B fibers of equine skeletal muscle, although several type 1 fibers in the vastus lateralis muscle were positive for GLUT4. In all muscle fibers examined microscopically, FAT/CD36 was strongly expressed in the sarcolemma and capillaries. Type 1 muscle fibers also expressed small intracellular amounts of FAT/CD36, but no intracellular FAT/CD36 expression was detected in type 2 fibers. CONCLUSIONS AND CLINICAL RELEVANCE: In equine skeletal muscle, GLUT4 and FAT/CD36 are expressed in a fiber type selective manner. 相似文献
66.
van Ginneken MM Keizer HA Wijnberg ID van Dam KG Schaart G de Graaf-Roelfsema E van der Kolk JH van Breda E 《American journal of veterinary research》2004,65(1):69-73
OBJECTIVE: To investigate whether protein kinase C (PKC) isoforms are expressed in equine skeletal muscle and determine their distribution in various types of fibers by use of immunofluorescence microscopy. ANIMALS: 5 healthy adult Dutch Warmblood horses. PROCEDURE: In each horse, 2 biopsy specimens were obtained from the vastus lateralis muscle. Cryosections of equine muscle were stained with PKC isoform (alpha, beta1, beta2, delta, epsilon, or zeta)-specific polyclonal antibodies and examined by use of a fluorescence microscope. Homogenized muscle samples were evaluated via western blot analysis. RESULTS: The PKC alpha, beta1, beta2, delta, epsilon, and zeta isoforms were localized within the fibers of equine skeletal muscle. In addition, PKC alpha and beta2 were detected near or in the plasma membrane of muscle cells. For some PKC isoforms, distribution was specific for fiber type. Staining of cell membranes for PKC alpha was observed predominantly in fibers that reacted positively with myosin heavy chain (MHC)-IIa; PKC delta and epsilon staining were more pronounced in MHC-I-positive fibers. In contrast, MHC-I negative fibers contained more PKC zeta than MHC-I-positive fibers. Distribution of PKC beta1 was equal among the different fiber types. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that PKC isoforms are expressed in equine skeletal muscle in a fiber type-specific manner. Therefore, the involvement of PKC isoforms in signal transduction in equine skeletal muscle might be dependent on fiber type. 相似文献
67.
OBJECTIVE: To test the hypotheses that kinematic data of the sagittal motion of canine hind limbs during walking obtained with a 2-dimensional (2-D) system correlate well with those obtained with a 3-dimensional (3-D) system and that the data obtained with the 2-D system are repeatable. ANIMALS: 6 adult dogs with no evidence of lameness. PROCEDURES: Hind limb motions of 6 walking dogs were recorded via 2-D video and 3-D optoelectric systems simultaneously. Five valid trials were digitized, and 5 data sets (2-D 60 Hz, 3-D 180 Hz, 3-D sagittal 180 Hz, 3-D 60 Hz, and 3-D sagittal 60 Hz) of a complete gait cycle were created for each dog. In sagittal data sets, 3-D data were reduced to exclude coordinates for mediolateral orientation. Temporospatial parameters; angles of hip, stifle, and tarsal joints; and coefficients of variation of angular measurements of each dog were calculated for each data set. Accuracy of the 2-D analysis was determined by calculating mean absolute differences and estimating agreement between the 2-D and 3-D 180-Hz data sets. RESULTS: Values of joint angles and angular excursions measured with the 2-D system were repeatable and agreed with respective values obtained with the 3-D system. Reduction of the sampling rate had a greater impact on values of kinematic variables obtained with the 3-D system than did elimination of data on mediolateral orientation. CONCLUSIONS AND CLINICAL RELEVANCE: Kinematic analysis using a 2-D video system provided accurate and repeatable data of the sagittal angular motion of canine hind limbs during walking. 相似文献
68.
Congenital vertebral malformations are common findings on diagnostic imaging of the vertebral column in “screw‐tailed” brachycephalic dogs. The aims of this study were to evaluate the prevalence and anatomical characteristics of lumbosacral congenital vertebral malformations in French Bulldogs, English Bulldogs, and Pugs presenting for problems unrelated to spinal disease, as well as possible associations with the degree of tail malformation, lumbosacral intervertebral disc herniation, or spondylosis deformans. In this retrospective cross‐sectional study, CT scans of vertebrae L6 to S3 and of the coccygeal vertebrae were reviewed for type of congenital vertebral malformations (hemivertebrae, block vertebrae, lumbosacral transitional vertebrae, and spina bifida), lumbosacral intervertebral disc herniation, lumbosacral spondylosis deformans, and degree of tail malformation. In 76 (51.0%) of the 149 included dogs (53 French Bulldogs, 37 English Bulldogs, and 59 Pugs) at least one type of congenital vertebral malformations was found, with lumbosacral transitional vertebrae being the most common (34.2%). There was a significantly higher prevalence of lumbosacral transitional vertebrae (54.2%) and lower prevalence of hemivertebrae (1.7%) in Pugs compared to English (13.5% and 24.3%, respectively) and French Bulldogs (26.4% and 32.0%, respectively). Tail malformation was significantly more severe in dogs with evidence of hemivertebrae. Congenital vertebral malformations are a common finding in the lumbosacral vertebral column of French Bulldogs, English Bulldogs, and Pugs. These anatomical variances need to be considered when interpreting diagnostic studies and when planning for neurosurgical and neurodiagnostic procedures. Furthermore, this study suggests a possible association between the degree of tail malformation and lumbosacral hemivertebrae. 相似文献
69.
Paul E Verweij Gert HJ Kema Bas Zwaan Willem JG Melchers 《Pest management science》2013,69(2):165-170
Azole resistance is an emerging problem in the opportunistic mould Aspergillus fumigatus. The triazoles are the most important agents for the management of Aspergillus diseases in humans. Selection for acquired resistance may occur in the hospital setting through exposure to high doses of azoles during azole therapy, but evidence is accumulating that A. fumigatus may become resistant to medical triazoles through environmental exposure to fungicides. The recovery of A. fumigatus isolates resistant to the medical triazoles from azole‐naive patients as well as from the environment strongly indicates an environmental route of resistance selection. Molecule alignment studies have identified five fungicides that share a very similar molecule structure with the medical triazoles, and thus may have selected for mechanisms that confer resistance to both groups of compounds. It is important to explore further the presumed fungicide‐driven route of resistance selection in order to implement effective preventive measures as the prevalence of azole resistance in A. fumigatus continues to increase and causes major challenges in the management of azole‐resistant Aspergillus diseases. Copyright © 2012 Society of Chemical Industry 相似文献
70.
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