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31.
Capelli G Nardelli S di Regalbono AF Scala A Pietrobelli M 《Veterinary parasitology》2004,123(3-4):143-148
Risk factors associated with Neospora caninum seroprevalence in north-eastern Italy in healthy dogs were assessed. Antibodies to N. caninum were found in 10.9% of 707 kennel and owned dogs by a commercial competitive ELISA (VMRD Inc.). All dogs were negative for Leishmania infantum by indirect fluorescent antibody test indicating no cross reactivity or association between the two protozoa in this area. Seroprevalence association with breed and age of dogs and other factors are discussed. 相似文献
32.
Ziniu Deng Stefano La Malfa Yuming Xie Xingyao Xiong Alessandra Gentile 《Scientia Horticulturae》2007
A cpDNA fragment of 34 genotypes belonging to Citrus and four related genera was amplified and sequenced. Chloroplast microsatellites were revealed with the length of repeats ranging from 25 to 44 bases. Other than the normal uninucleotide poly(A) repeats, a trinucleotide poly(TAA) motif was also found, the first report of such repeats in a plant chloroplast genome. According to SSR structure variations, 18 Chloroplast SSR Types (CST) were identified. The CST sequences were informative for better understanding the genetic relationships of chloroplast genomes among the analyzed genotypes and confirmed some previous hypotheses about the female parent of several hybrid accessions. 相似文献
33.
Fingerprinting of alfalfa meiotic mutants using RAPD markers 总被引:5,自引:0,他引:5
Summary A calendar of female sporogenesis and gametogenesis was made for both apomictic tetraploid (2n=4x=36) Brachiaria brizantha and Brachiaria decumbens and their apomictic F1 hybrids with sexual tetraploid (2n=4x=36) Brachiaria ruziziensis. Microgametogenesis was used as a reference. Apospory was facultative in both species and hybrids. Environmental conditions had variable effects on the level of apomixis according to each genotype. Ratios of segregation into sexuals and apomicts in the interspecific hybrids suggest an oligogenic determinism with dominant apomixis in the genus Brachiaria. Highly apomictic and partially male fertile hybrids were identified and will be used in an improvement program to transfer genes for apomixis into the sexual species B. ruziziensis. 相似文献
34.
Levels of genetic similarity characterizing 20 grasspea (Lathyrus sativus L.) populations collected in central Italy (17 populations in the Marche region and three populations in the Abruzzo region) were analysed with amplified fragment length polymorphism (AFLP) molecular markers. Two main clusters were found: one included large‐seeded populations from farms that were not market‐oriented (named Household populations) and the second, small‐seeded populations, cultivated in market‐oriented farms (named Commercial populations). Relationships among populations collected in different regions were found, although one population of the Abruzzo region was placed between the two main clusters, suggesting a possible further genetic differentiation within this grasspea germplasm collection. Principal component analysis based on AFLP marker frequency was effective in identifying polymorphic markers showing high discriminating ability between clusters H and C. In particular, seven markers showing high positive and three markers with low negative PC1 scores showed an almost cluster‐specific distribution. These results will be useful for enhancing Italian grasspea germplasm use in plant‐breeding programmes and for extending grasspea cultivation within the sustainable agricultural systems of central Italy. 相似文献
35.
Corrigendum
Phenotypic recurrent selection for 2n pollen and 2n egg production in diploid alfalfa 相似文献36.
The rheological properties of tomato juice containing 1.5% soy germ were compared to plain tomato juice with and without soy protein isolate. This novel product was developed to provide a delivery system of carotenoids, soy protein, and significant isoflavone content without compromising the perceived juice characteristics of tomato product. Rheological tests depicted physical gel characteristics for all three products. Dynamic tests as a function of temperature showed that the stability and the compatibility between tomato juice and soy germ were higher as compared to soy protein isolate. The hydrophobic and electrostatic interactions between pectin and protein in the tomato soy protein isolate system were weakened as the temperature was increased. In the case of tomato juice with soy germ, the viscosity did not change during heating. The addition of soy germ increased the viscosity of tomato juice reinforcing the entire system without major qualitative effects on the rheological properties of plain tomato juice. 相似文献
37.
Prof. Enrico Porceddu Dr. Stefano Vannella Dr. Pietro Perrino 《Genetic Resources and Crop Evolution》1981,29(1):251-266
Summary A study was undertaken using 48 characters observed in plants, spikes and seeds in order to determine the amount of information of different characters and their taxonomic importance in tetraploid wheat samples from Sicily. A classification of the material was also attempted using similarity indices.The most important characters appear: leaf pubescence, glume colour and length, and seed colour. Using all characters, similarity indices among samples were computed and a classification was worked out. This classification, which is very similar to those proposed by various scientists, produces hierarchical groups, showing different levels of merging, and offers very interesting hypotheses on the evolution of the Siciliandurum wheats.
Merkmalsanalyse und numerische Klassifikation an einer Weizen-Kollektion aus Sizilien
Zusammenfassung Untersucht wurden 48 Pflanzen-, Ähren- und Kornmerkmale an Proben tetraploider Weizen aus Sizilien, um den Informationsgehalt unterschiedlicher Merkmale und ihren taxonomischen Wert zu erfassen. Anhand von Ähnlichkeitsindices wurde auch eine Klassifikation des Materials vorgenommen.Als bedeutsamste Merkmale erscheinen: Blattpubeszenz, Spelzenfarbe und-länge und Kornfarbe. Auf der Grundlage aller Merkmale wurden Ähnlichkeitsindices zwischen den Proben errechnet und eine Klassifikation ausgearbeitet. Diese ist den Klassifikationen anderer Wissenschaftler sehr ähnlich, ergibt hierarchische Gruppen mit unterschiedlichem Ähnlichkeitsniveau und ermöglicht die Aufstellung einer interessanten Hypothese zur Evolution der sizilianischendurum- Weizen.
48 , . . : , , . . , .相似文献
38.
Zosima absinthifolia (ZA) extracts and the coumarins (+)-columbianadin and (-)-deltoin were evaluated for their potential hepatoprotective and antiinflamatory effects in a CCl(4)-induced hepatotoxicity assay in rats and by the inhibition of TNF-α production on LPS-stimulated THP-1 macrophages, respectively. Both the ZA extracts and the coumarins showed hepatoprotective activity confirmed by monitoring the ALT/AST levels and by histopathological examination. The antiinflamatory activity, proved by the inhibition of TNF-α production, was found to be higher for the n-hexane root extract than for coumarins, suggesting synergic potential of the extract. The concentration of (-)-deltoin and (+)-columbianadin in extracts was determined by HPLC analysis. 相似文献
39.
Amer Ibrahim Basha Stefano Padulosi Kamel Chabane Adnan Hadj-Hassan Ehsan Dulloo Mario Augusto Pagnotta Enrico Porceddu 《Genetic Resources and Crop Evolution》2007,54(8):1807-1816
Pistachio (Pistacia vera L.) is a strategic nut tree species in the Middle East which holds comparative advantage over other fruit trees in view of
its hardiness, income generation opportunities and benefits for the ecosystem. Yet pistachio cultivation depends on a very
narrow genetic base, in spite of the existence of many varieties still marginally exploited. Syria is an important center
of diversity for pistachio. A country wide ecogeographic survey in this country was carried out to determine the extent of
pistachio genetic diversity and its use. As a whole, 114 accessions were collected from 37 farms to assess diversity at morphological
and molecular level. Molecular evaluation was carried out using Amplified Fragment Length Polymorphism (AFLP) technique and
performed using seven primer pair combinations. Results from the studies allowed the identification of 25 pistachio female
varieties in Syria, some of which unique and described for the first time. Three groups of pistachio diversity were identified
by cluster analysis which provides useful information about the distribution of genetic diversity in Syria for enhanced use
and sustainable conservation. 相似文献
40.
Früh-Green GL Kelley DS Bernasconi SM Karson JA Ludwig KA Butterfield DA Boschi C Proskurowski G 《Science (New York, N.Y.)》2003,301(5632):495-498
Strontium, carbon, and oxygen isotope data and radiocarbon ages document at least 30,000 years of hydrothermal activity driven by serpentinization reactions at Lost City. Serpentinization beneath this off-axis field is estimated to occur at a minimum rate of 1.2 x 10(-4) cubic kilometers per year. The access of seawater to relatively cool, fresh peridotite, coupled with faulting, volumetric expansion, and mass wasting processes, are crucial to sustain such systems. The amount of heat produced by serpentinization of peridotite massifs, typical of slow and ultraslow spreading environments, has the potential to drive Lost City-type systems for hundreds of thousands, possibly millions, of years. 相似文献