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201.
F. Calle J. C. Perez W. Gaitán N. Morante H. Ceballos G. Llano E. Alvarez 《Euphytica》2005,144(1-2):177-186
There is a limited knowledge on the inheritance of traits with agronomic relevance in cassava. A diallel study among 10 parental
clones was conducted in the acid-soils environment in the eastern savannas of Colombia. Thirty clones were obtained for each
F1 cross. Each clone was represented by six plants, which were distributed in three replications at two locations. Therefore,
the same 30 genotypes of each F1 cross were planted in the three replications at the two locations. Analysis of variance suggested
significant effects for five of the six variables analyzed (harvest index, dry matter content, height of first branching,
reaction to super elongation disease, and plant type scores). Fresh root yield showed strong genotype × environment interaction
and differences between crosses reached statistical significance in only one of the two environments analyzed. General and
specific combining ability effects and their interaction with the environment were significant for most of the variables as
well. Results suggested that dominance plays an important role particularly in the cases of fresh root yield and harvest index. 相似文献
202.
Gerardo Della Sala Thomas Hochmuth Roberta Teta Valeria Costantino Alfonso Mangoni 《Marine drugs》2014,12(11):5425-5440
Sponge-associated microorganisms are able to assemble the complex machinery for the production of secondary metabolites such as polyketides, the most important class of marine natural products from a drug discovery perspective. A comprehensive overview of polyketide biosynthetic genes of the sponge Plakortis halichondrioides and its symbionts was obtained in the present study by massively parallel 454 pyrosequencing of complex and heterogeneous PCR (Polymerase Chain Reaction) products amplified from the metagenomic DNA of a specimen of P. halichondrioides collected in the Caribbean Sea. This was accompanied by a survey of the bacterial diversity within the sponge. In line with previous studies, sequences belonging to supA and swfA, two widespread sponge-specific groups of polyketide synthase (PKS) genes were dominant. While they have been previously reported as belonging to Poribacteria (a novel bacterial phylum found exclusively in sponges), re-examination of current genomic sequencing data showed supA and swfA not to be present in the poribacterial genome. Several non-supA, non-swfA type-I PKS fragments were also identified. A significant portion of these fragments resembled type-I PKSs from protists, suggesting that bacteria may not be the only source of polyketides from P. halichondrioides, and that protistan PKSs should receive further investigation as a source of novel polyketides. 相似文献
203.
Gerardo A. Belandria Michael M. Pavletic James P. Boulay Dominique G. Penninck Leslie A. Schwarz 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(7):733-740
Surgical stapling equipment was used to create a gastropexy in 20 dogs undergoing
emergency surgery for gastric dilatation and volvulus (GDV). The technique
involved creation of a tunnel between the seromuscular layer and the submucosa
of the pyloric antrum, and a matching tunnel beneath the right m. transversus
abdominis. The arms of a gastrointestinal anastomosis stapling device were
introduced into the tunnels, and the device was fired to create the gastropexy.
One dog died of systemic sequelae of GDV during the early postoperative period.
None of the remaining 19 dogs developed a recurrence of GDV during follow-up
periods ranging from 5 to 43 months. In 11 dogs, the integrity of the gastropexy
was evaluated by abdominal ultrasonography and either negative contrast
gastrography or double contrast gastrography; in these dogs, the radiographic
and/or the ultrasonographic findings were suggestive of an intact gastropexy.
There were no complications involving the gastropexy staple line. The results of
this study indicate that an effective and consistent permanent gastropexy can be
created, using surgical stapling equipment. 相似文献
204.
The absolute quantities and the stereoisomeric ratios of R, S-2-hydroxybutanone and R, R-, S, S-, R, S ( meso)-2,3-butanediol were determined in batteries of traditional balsamic vinegar (TBV) by gas chromatography-mass spectrometry (GC-MS), using a chiral capillary column, to evaluate if such parameters could be used to differentiate TBV differently aged and from different producers. Results showed that the initial amounts of 2-hydroxybutanone and 2,3-butanediol were quite variable, as a function of the producer of the vinegar; moreover, the 2-hydroxybutanone amount decreased during aging while 2,3-butanediol increased. Initially, the R-2-hydroxybutanone form prevails, and then the R/ S ratio decreased regularly during aging with some exceptions attributed to the addition of new barrels during the battery management. With regard to the 2,3-butanediol isomers, the most abundant was the R, R form, slowly transformed into the R, S and S, S isomers during aging. The GC-MS method used is easy and fast and could allow for a quick control of the maturation level of the vinegar. 相似文献