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排序方式: 共有219条查询结果,搜索用时 15 毫秒
111.
Lindsay Tomlinson Laura I. Boone Lila Ramaiah Kelley A. Penraat Barbara R. von Beust Mehrdad Ameri Florence M. Poitout‐Belissent Kurt Weingand Heather C. Workman Adam D. Aulbach Dennis J. Meyer Diane E. Brown Amy L. MacNeill Anne Provencher Bolliger Denise I. Bounous 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2013,42(3):252-269
The purpose of this paper by the Regulatory Affairs Committee (RAC) of the American Society for Veterinary Clinical Pathology (ASVCP) is to review the current regulatory guidances (eg, guidelines) and published recommendations for best practices in veterinary toxicologic clinical pathology, particularly in the pharmaceutical and biotechnology industries, and to utilize the combined experience of ASVCP RAC to provide updated recommendations. Discussion points include (1) instrumentation, validation, and sample collection, (2) routine laboratory variables, (3) cytologic laboratory variables, (4) data interpretation and reporting (including peer review, reference intervals and statistics), and (5) roles and responsibilities of clinical pathologists and laboratory personnel. Revision and improvement of current practices should be in alignment with evolving regulatory guidance documents, new technology, and expanding understanding and utility of clinical pathology. These recommendations provide a contemporary guide for the refinement of veterinary toxicologic clinical pathology best practices. 相似文献
112.
Regina M. Tende Stephen N. Mugo John H. Nderitu Florence M. Olubayo Josephine M. Songa David J. Bergvinson 《Crop Protection》2010
Susceptibility of Chilo partellus (Lepidoptera, Crambidae) and Busseola fusca (Lepidoptera, Noctuidae) populations to Cry proteins from the bacterium, Bacillus thuringiensis (Bt), the δ-endotoxins Cry1Ab and Cry1Ba in Bt-maize, were evaluated under biosafety greenhouse conditions. Larval feeding on Bt-maize was adjusted to deliver sub-lethal doses of δ-endotoxins from the two events; survivors were reared on artificial diet to obtain successive generations. Eight generations of three C. partellus populations and five generations of a B. fusca population were screened for susceptibility on each event. Mean proportion of surviving larvae from Bt-maize plants, and the corresponding pupal weights of survivors for each population, were lower for individuals exposed to δ-endotoxins. Both Bt Cry proteins expressed in maize leaves controlled C. partellus and showed stability in control, with no indication of a change in susceptibility among generations. Neither toxin, however, provided complete control of B. fusca, but no changes in susceptibility were observed after five generations of selection. Implications for development of future transgenic Bt maize events, and research for East Africa are discussed. 相似文献
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118.
Florence Cassel 《Water, air, and soil pollution》2017,228(5):186
Drought is a serious concern in many parts of the world, including in California, where paucity of available irrigation water has impaired crop production and soil health through salt accumulation. With extending water and salinity crises, there is a need for advanced salt and vegetation management. To develop more efficient management solutions, Slingram electromagnetic investigations and stochastic and statistical analyses were performed for determining optimal vegetable yields in a salt-affected farmland. The Slingram results were evaluated using multi-linear regression analyses, and the yield and salinity were characterized for central tendency, variance, distributions and symmetry. The yields of two studied vegetable crops, lettuce and tomato, increased with decreasing salinity load. The average lettuce and tomato yield potentials were 55 and 75%, respectively. The minimum yield potential for tomato was 9.5 times higher than that for lettuce. The mode value for conductivity (ECe) was 650 mS m?1, which corresponded to 50% yield loss. The yield loss was <10% in locations with ECe < 250 mS m?1. In zones with ECe > 850 mS m?1, the yield reductions for lettuce and tomato reached up to 96 and 60%, respectively. About 57 and 82% of the field area could be limited to 20% yield potentials for tomato and lettuce, respectively. Lettuce had a higher cost benefit than tomato albeit with a greater yield potential of the latter crop. By delineating the spatial contours of salt-induced yield variability, vegetables can be grown in segmented soil zones based on salinity levels. 相似文献
119.
Ahmed Maouche Edouard Curran Anne-Sophie Goupil Elisabeth Sambroni Johanna Bellaiche Florence Le Gac Jean-Jacques Lareyre 《Fish physiology and biochemistry》2018,44(6):1599-1616
The present study aimed to investigate whether the Gfra1/Gdnf and/or Kit/Kitlg regulatory pathways could be involved in the regulation of spermatogonial cell proliferation and/or differentiation in fish. Homologs of the mammalian gfra1, gdnf, kitr, and kitlg genes were identified in gnathostomes and reliable orthologous relationships were established using phylogenetic reconstructions and analyses of syntenic chromosomal fragments. Gene duplications and losses occurred specifically in teleost fish and members of the Salmoninae family including rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). Some duplicated genes exhibited distinct spatiotemporal expression profiles and were differently regulated by hormones in rainbow trout. Undifferentiated type A spermatogonia expressed higher levels of kitrb and kitra2 making them possible target cells for the gonadal kitlgb and somatic kitlga before the onset of spermatogenesis. Interestingly, gdnfa and gdnfb ohnologous genes were poorly expressed before the onset of spermatogenesis. The expression level of gdnfb was correlated with that of the vasa gene suggesting that the late increased abundance of gdnfb during spermatogenesis onset was due to the increased number of spermatogonial cells. gfra1a2 was expressed in undifferentiated type A spermatogonia whereas gfra1a1 was mainly detected in somatic cells. These observations indicate that the germinal gdnfb ligand could exert autocrine and paracrine functions on spermatogonia and on testicular somatic cells, respectively. Fsh and androgens inhibited gfra1a2 and gdnfb whereas gfra1a1 was stimulated by Fsh, androgens, and 17α, 20β progesterone. Finally, our data provide evidences that the molecular identity of the male germ stem cells changes during ontogenesis prior to spermatogenesis onset. 相似文献
120.
Florence Hiu Yan Lui Yoko Kurokochi Hiroe Narita Yukie Saito Masatoshi Sato 《Journal of Wood Science》2018,64(3):246-255
Binderless boards are composite boards that rely on self-bonding mechanisms for inter-fibre bonding. Quercus acutissima and Quercus serrata logs degraded by Lentinula edodes (shiitake fungi) were used in this study to investigate whether physical and chemical changes induced by shiitake fungi can enhance board mechanical properties. Binderless boards were manufactured with 0.8 g/cm3 target density, 220 °C pressing temperature, 5 MPa pressure, and pressing duration of 10 min. Boards made from logs degraded for ≥?26 months were stronger than control boards and met modulus of rupture (MOR) and internal bonding (IB) requirements for fibreboards. Chemical composition and particle size distribution of the wood powder used to make the boards were determined to elucidate the drivers of board mechanical properties. The proportion of small particles (<?150 µm) showed a strong positive correlation with MOR for both species and hot water extractives showed a strong positive correlation with IB for Q. acutissima boards. Introduction of shiitake fungi pre-treatment to the production process may enhance the mechanical strength of binderless boards. 相似文献