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41.
M Alonso N Alonso Rodriguez C Garzelli M Martínez Lirola M Herranz S Samper MJ Ruiz Serrano E Bouza D García de Viedma 《BMC microbiology》2010,10(1):151
Background
The Beijing lineage of Mycobacterium tuberculosis is causing concern due to its global distribution and its involvement in severe outbreaks. Studies focused on this lineage are mainly restricted to geographical settings where its prevalence is high, whereas those in other areas are scarce. In this study, we analyze Beijing isolates in the Mediterranean area, where this lineage is not prevalent and is mainly associated with immigrant cases. 相似文献42.
43.
Khan NA Githiri SM Benitez ER Abe J Kawasaki S Hayashi T Takahashi R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,117(4):479-487
Early-maturing cultivars of soybean [Glycine max (L.) Merr.] native to the shores of the Sea of Okhotsk (Sakhalin and Kuril Islands) and eastern Hokkaido (northern Japan) have a strong tendency to produce cleistogamous flowers throughout their blooming period. A previous study revealed that cleistogamy is controlled by a minimum of two genes with epistatic interaction, one of which is associated with a maturity gene responsible for insensitivity to incandescent long daylength (ILD). This study was conducted to determine the genetic basis of cleistogamy in more detail by QTL mapping. F(2) to F(4) progenies derived from a cross between a cleistogamous cv. Karafuto-1 and a chasmogamous cv. Toyosuzu were used. A molecular linkage map spanning 2,180 cM comprising 500 markers was constructed using 89 F(2) plants. The markers were distributed in 25 linkage groups. An interval mapping method to analyze categorical traits identified four QTLs for cleistogamy, cl1, cl2, cl3 and cl4, in molecular linkage groups (MLGs) C2, D1a, I and L, respectively. Alleles derived from Karafuto-1 had additive effects to increase probability of cleistogamy at cl3 and cl4, whereas the alleles had additive effects to decrease the probablity at cl1 and cl2. Progeny test confirmed the effects of cl3, which had the highest LOD score (5.20). Composite interval mapping revealed four QTLs for flowering date, fd5-fd8. Judging from relative location with markers and association with ILD responses, fd7 and fd8 may correspond to maturity genes E4 and E3, respectively. cl3 and cl4 were located at similar positions as fd7 and fd8, suggesting that the two maturity genes may control cleistogamy by either pleiotropy or close linkage. 相似文献
44.
F. J. Benitez J. Beltran-Heredia F. J. Real J. L. Acero 《Bioprocess and biosystems engineering》1999,21(5):459-464
The decomposition of the organic substrate present in wine distillery wastewaters (WDW) is studied in batch reactors, by an ozonation process, by an aerobic degradation and by another ozonation of the aerobically pretreated wastewaters. In the ozonation process, the effects on the substrate removal obtained of the temperature, pH and the presence of H2O2 and UV radiation are established, and an approximate kinetic study is conducted which leads to the evaluation of the apparent kinetic constants for the substrate reduction. In the aerobic degradation treatment, the evolution of the substrate, biomass and total phenolic compounds are followed during the process, and a kinetic study is performed by using the Contois model, which applied to the experimental data provides the specific kinetic parameters qmax and K1. Finally, in the ozonation of the pretreated wastewaters, the?influence of the operating variables is established, and the effect of this aerobic pretreatment on the substrate removal and kinetic constants obtained in the ozonation stage is also discussed. 相似文献
45.
F. J. Benitez J. Beltran-Heredia J. Torregrosa J. R. Dominguez 《Bioprocess and biosystems engineering》1999,21(4):355-361
The reduction of the pollutant organic matter present in wastewaters generated in the black olive production process is studied by an aerobic degradation, and by the combination of two successive steps: an ozonation pretreatment followed by an aerobic degradation. In the single aerobic process, in addition to the biomass evolution which is followed during each experiment, the removal of the pollutant load is evaluated by means of global parameters which are directly related with the organic matter, as the chemical oxygen demand and the total phenolic compounds content. A kinetic study is performed by using the Monod model, which applied to the experimental data, provides the specific kinetic parameters of this model: the kinetic constant for the substrate decomposition rate, the cellular yield coefficient and the kinetic constant for the biomass decrease during the death phase of microorganisms. In the combined process, an ozonation pretreatment is conducted with experiments where the ozone partial pressure is varied, and an important reduction in the phenolic compounds is achieved. The kinetic parameters of the following aerobic degradation stage are also evaluated, and the effect of the chemical oxidation pretreatment on this biological stage is discussed. 相似文献
46.
Marmoset phylogenetics, conservation perspectives, and evolution of the mtDNA control region 总被引:2,自引:1,他引:2
Tagliaro CH; Schneider MP; Schneider H; Sampaio IC; Stanhope MJ 《Molecular biology and evolution》1997,14(6):674-684
Marmosets (genus Callithrix) are a diverse group of platyrrhine primates
with 13-15 purported taxa, many of them considered endangered.
Morphological analyses constitute most of the basis for recognition of
these forms as distinct taxa. The purpose of this study was to provide a
molecular view, based on mitochondrial control region sequences, of the
evolutionary history of the marmosets, concomitant with a molecular
phylogenetic perspective on species diversity within the group. An
additional purpose was to provide the first comparative examination of a
complete New World monkey control region sequence with those of other
mammals. The phylogenetic analyses provide convincing support for a split
between the Atlantic forest and Amazonian marmosets, with the inclusion of
the pygmy marmoset (Cebuella pygmaea) at the base of the Amazonian clade.
The earliest branch of the Atlantic forest group was C. aurita. In the
Amazonian group, the analyses do not support the recognition of C.
humeralifer and the recently described C mauesi as distinct taxa. They do,
however, support a clear distinction between C. argentata and a strongly
supported mixed clade of C. humeralifer and C. mauesi. In the Atlantic
forest group, the phylogenetic tree suggests mixing between C. penicillata,
C. kuhli, and possibly C. jacchus. Most of the sequence features
characteristic of other mammal control regions were also evident in
marmosets, with the exception that conserved sequence blocks (CSBs) 2 and 3
were not clearly identifiable. Tandem repeat units often associated with
heteroplasmy in a variety of other mammals were not evident in the marmoset
sequences.
相似文献
47.
48.
49.
Bakker MF Verstappen SM Welsing PM Jacobs JW Jahangier ZN van der Veen MJ Bijlsma JW Lafeber FP;Utrecht Arthritis Cohort study group 《Arthritis research & therapy》2011,13(3):R70
Introduction
The aim of this study was to investigate whether serum biomarker levels of C2C, C1,2C, CS846, and CPII can predict the long-term course of disease activity and radiographic progression early in the disease course of rheumatoid arthritis (RA). 相似文献50.