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81.
Summary In a world lentil collection the distribution of variation amongst accessions from 13 major lentil-producing countries was examined on the basis of nine quantitative morphological characters by discriminant analysis and canonical analysis. Stepwise discriminant analysis revealed major differences between accessions from different countries. Three major regional groups were apparent: 1) a levantine group (Egypt, Jordan, Lebanon and Syria, 2) a more northern group composed of Greece, Iran, Turkey, and USSR, and 3) accessions from India and Ethiopia with strikingly similar quantitative morphological characters. Misclassifications of individuals within groups were frequent. Characters useful in discriminating between accessions from different countries were in descending order of importance: time to maturity, lowest pod height and 100-seed weight. The regional grouping indicates the importance of local adaptation through clusters of associated characters with phenological adaptation to the ecological environment as the major evolutionary force in the species. 相似文献
82.
R. Lágler G. Gyulai M. Humphreys Z. Szabó L. Horváth A. Bittsánszky J. Kiss L. Holly L. Heszky 《Euphytica》2005,146(1-2):77-85
Summary Morphological characterization of 20 common millet (Panicum miliaceum L., 2n = 4x = 36) cultivars and landraces revealed four distinct clusters which were apparently consistent with the grain colors of black,
black and brown, red, yellow, and white. Seed remains of medieval millet, recovered from a 15th century layer (King's Palace,
Budapest, Hungary), showed reddish yellow grain color after rehydrating on tissue culture medium that was close to grain color
of modern cultivar Omszkoje. aDNA of medieval commom millet was extracted successfully, analyzed and compared to modern common millets by ISSR, SSR,
CAP and mtDNA. Analyses of fragments and sequences revealed polymorphism at seven ISSR loci (15 alleles) and at the 5S-18S
rDNA locus of mtDNA. CAP analysis of the 5S-18S rDNA fragment revealed no SNPs in the restriction sites of six endonucleases
TaqI, BsuRI, HinfI, MboI, AluI and RsaI. Sequence alignments of the restriction fragments RsaI also revealed consensus sequence in the medieval sample compared to a modern variety. An attempted phenotype reconstruction
indicated that medieval common millet showed the closest morphological similarity to modern millet cultivar Omszkoje. 相似文献
83.
H. Holly Wang Hao Zhang 《Journal of Agricultural, Biological & Environmental Statistics》2002,7(1):107-127
A model-based clustering method for cross-sectional time series data is proposed and applied to crop insurance programs. To
design an effective grouprisk plan, an important step is to group together the farms that resemble each other and decide the
number of clusters, both of which can be achieved via the model-based clustering. The mixture maximum likelihood is employed
for inferences. However, with the presence of correlation and missing values, the exact maximum likelihood estimators (MLEs)
are difficult to obtain. An approach for obtaining approximate MLEs is proposed and evaluated through simulation studies.
A bootstrapping method is used to choose the number of components in the mixture model. 相似文献
84.
Summary The history of collecting Hungarian land-races and their present preservation techniques and system are briefly summarized in this paper.
Die Erhaltung ungarischer Landsorten als genetische Ressourcen
Zusammenfassung Die Geschichte der Sammlung ungarischer Landsorten und die gegenwärtige Technik ihrer Erhaltung wird kurz zusammengefaßt dargestellt.
.相似文献
85.
86.
Holly L. Stewart Jeffery H. Siewerdsen Brad B. Nelson Christopher E. Kawcak 《Equine veterinary journal》2021,53(5):872-885
Access to volumetric imaging modalities, such as magnetic resonance imaging (MRI) and computed tomography (CT), has increased over the past decade and has revolutionised the way clinicians evaluate equine anatomy. More recent advancements have resulted in the development of multiple commercially available cone-beam CT (CBCT) scanners for equine use. CBCT scanners modify the traditional fan-shaped beam of ionising radiation into a three-dimensional pyramidal- or cone-shaped beam of radiation. This modification enables the scanner to acquire sufficient data to create diagnostic images of a region of interest after a single rotation of the gantry. The rapid acquisition of data and divergent X-ray beam causes some artifacts to be more prominent on CBCT images—as well as the unique cone-beam artifact—resulting in decreased contrast resolution. While the use of CT for evaluation of the equine musculoskeletal anatomy is not new, there is a paucity of literature and scientific studies on the capabilities of CBCT for equine imaging. CBCT units do not require a specialised table for imaging and in some cases are portable for imaging in the standing or anaesthetised patient. This review article summarises the basic physics of CT technology, including how CBCT imaging differs, and provides objective information about the strengths and limitations of this modality. Finally, potential future applications and techniques for imaging with CT which will need to be explored in order to fully consider the capabilities of CT imaging in the horse are discussed. 相似文献
87.
88.
Yates AC Stewart AA Byron CR Pondenis HC Kaufmann KM Constable PD 《American journal of veterinary research》2006,67(12):1980-1986
OBJECTIVE: To determine the effects of sodium hyaluronate (HA) in combination with methylprednisolone acetate (MPA) on interleukin-1 (IL-1)-induced inflammation in equine articular cartilage pellets. Sample POPULATION: Chondrocytes collected from 7 horses euthanatized for problems unrelated to the musculoskeletal system. PROCEDURES: Chondrocyte pellets were treated with medium (negative control); medium containing IL-1 (positive control); or medium containing IL-1 with MPA only (0.05 or 0.5 mg/mL), HA only (0.2 or 2 mg/mL), or MPA (0.05 or 0.5 mg/mL) and HA (0.2 or 2 mg/mL) in combination. Proteoglycan (PG) synthesis was determined by incorporation of sulfur 35-labeled sodium sulfate into PGs. Glycosaminoglycan (GAG) content of the media and the pellets and total pellet DNA content were determined. RESULTS: Methylprednisolone acetate at 0.5 mg/mL caused an increase in PG synthesis, whereas HA had no effect alone. The combination of MPA, both 0.05 mg/mL and 0.5 mg/mL, with HA at 2 mg/mL increased PG synthesis, compared with IL-1-treated control. All treatment groups containing the high concentration of MPA (0.5 mg/mL) and the high concentration of HA (2.0 mg/mL) had pellets with increased GAG content. The addition of HA caused an increase in total GAG content in the media, regardless of MPA treatment. Cyclooxygenase-2 mRNA and aggrecan mRNA expression was significantly reduced with MPA treatment. Total pellet DNA content was unchanged by any treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Our results indicate that MPA in combination with HA has beneficial effects on PG metabolism of IL-1-treated equine chondrocytes. 相似文献
89.
Jeffrey R. Bloomquist Holly J. Ferguson Eric D. Cox M. Sreenivasa Reddy James M. Cook 《Pest management science》1997,51(1):1-6
Little information is available on the actions of β-carboline convulsants on insect GABA receptors or their potential as insecticides. Accordingly, two compounds (3-ethoxy-β-carboline, 3-EBC; dimethoxy-β-carboline-3-methyl ester, DMCM) were studied for their effects on Drosophila melanogaster larval neuron discharge and also in lethality bioassays on adult female D. melanogaster and adult male Blattella germanica. Recordings of nerve spiking in the isolated larval central nervous system showed that 3-EBC and DMCM inhibited nerve discharge, and this inhibitory effect was not additive with that of GABA, confirming that the inhibition was expressed through an action on the GABA receptor. Nerve blockage induced by β-carbolines could not be reversed by picrotoxinin, indicating that there may exist some overlap or negative allosteric coupling between the picrotoxinin and β-carboline binding sites. DMCM and 3-EBC effectively antagonized the effects of exogenously applied GABA in nerve preparations from insecticide-susceptible larvae. In contrast, preparations from the rdl strain of D. melanogaster, which possesses a GABA receptor that is highly resistant to cyclodienes and related convulsants, were less sensitive to the GABA antagonist effect of DMCM. Neither of the β-carbolines produced any appreciable mortality in insects, even when synergized with piperonyl butoxide or S,S,S-tributyl phosphorotrithioate, The toxicity of the β-carbolines is probably limited by their relatively weak effects on the GABA receptor and perhaps also by pharmacokinetic factors. These considerations, coupled with the cross-resistance observed in cyclodiene-resistant insects, suggest that the currently available β-carbolines are not viable as lead compounds for insecticide screening efforts. © 1997 SCI. 相似文献
90.