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31.
Mapping of resistance to the potato cyst nematode Globodera rostochiensis from the wild potato species Solanum vernei 总被引:1,自引:0,他引:1
Jeanne M. E. Jacobs Herman J. van Eck Karin Horsman Paul F. P. Arens Brigitte Verkerk-Bakker Evert Jacobsen Andy Pereira Willem J. Stiekema 《Molecular breeding : new strategies in plant improvement》1996,2(1):51-60
A population of diploid potato (Solanum tuberosum) was used for the genetic analysis and mapping of a locus for resistance to the potato cyst nematode Globodera rostochiensis, introgressed from the wild potato species Solanum vernei. Resistance tests of 108 genotypes of a F1 population revealed the presence of a single locus with a dominant allele for resistance to G. rostochiensis pathotype Ro1. This locus, designated GroV1, was located on chromosome 5 with RFLP markers. Fine-mapping was performed with RAPD and SCAR markers. The GroV1 locus was found in the same region of the potato genome as the S. tuberosum ssp. andigena H1 nematode resistance locus. Both resistance loci could not excluded to be allelic. The identification of markers flanking the GroV1 locus offers a valuable strategy for marker-assisted selection for introgression of this nematode resistance.Abbreviations BSA
bulked segregant analysis
- RAPD
random-amplified polymorphic DNA
- RFLP
restriction fragment length polymorphism
- SCAR
sequence-characterized amplified region 相似文献
32.
José A. A. Sant''Ana Pereira Arnold De Haan Andy Wessels Antoon F. M. Moorman Anthony J. Sargeant 《The Histochemical journal》1995,27(9):715-722
Summary In the present study we report a novel histochemical method which, by sequential pre-incubations in alkaline and acidic media,
selectively differentiates muscle fibres expressing myosin heavy chain IIX, on the basis of a specific profile for myofibrillar
actomyosin ATPase (mATPase) activity. The enzyme reactions were tested for specificity by means of anti-myosin heavy chain
monoclonal antibodies, which were characterized on Western blots of muscle homogenates. Enzyme histochemical reactions with
the traditional pH buffers were compared to those of the new method and, in conjunction with the immunoreactions, used to
confirm the relationship between MyHC expression and the distinct profiles for mATPase. Imrnunohistochemical reactions demonstrated
that the new method only differentiates those fibres expressing myosin heavy chain IIX. The method revealed a continuum in
which the intermediate staining intensities corresponded to hybrid fibres expressing myosin heavy chain IIX in combination
with either the IIA or IIB forms. Quantitative histochemistry and immunohistochemistry (by image analysis), used to examine
the relationship between staining intensities for mATPase and amounts of myosin heavy chain IIX expression, revealed that
the new method discriminates well between hybrid fibres expressing variable amounts of the IIX isoform (r2 = 0.93). 相似文献
33.
Thomas L. German Scott Adkins Andy Witherell Kathryn E. Richmond William R. Knaack David K. Willis 《Plant Molecular Biology Reporter》1995,13(2):110-117
Mechanical inoculation ofArabidopsis thaliana ecotype Columbia with tomato spotted wilt virus led to viral replication and spread as determined by dot blot and ELISA analysis.
Severe symptoms were observed three to four weeks post-inoculation. Early symptoms were manifested as chlorotic spots on uninoculated
leaves. Later in the infection process, some plants showed complete chlorosis and wilting prior to bolting. Bolts that were
developed by infected plants were chlorotic and deformed. These preliminary results suggest thatA. thaliana could become a model system for the genetic analysis of host factors required for the replication of viruses in the family
Bunyaviridae, which includes viruses that cause important diseases of both plants and animals. 相似文献
34.
Summary In an effort to establish the reasons for the limitations in the final ethanol concentration of Zymomonas mobilis fermentation, the effects of CO2 and ethanol on the fermentation were investigated using continuous and fed-batch cultivation systems. The nucleation and
stripping out of CO2 from the fermenter using diatomaceous earth or nitrogen gas or both exhibited a profound effect on the glucose uptake rate
during the early stages of fed-batch fermentation, but did not improve final ethanol yields. The addition of ethanol together
with above mentioned experiments confirmed conclusively that ethanol inhibition is responsible for the final ethanol concentration
obtainable during Zymomonas mobilis fermentation. The final concentration lies between 90 and 110 gl−1 or approximately 12–15% (v/v) ethanol. 相似文献
35.
A Semimechanistic mathematical model is developed which describes the growth of Rhizopus oligosporus in a model solid-state fermentation system. Equations are presented for the release of glucoamylase, the diffusion of glucoamylase, the hydrolysis of starch, the generation and diffusion of glucose, and the uptake of glucose and conversion into new biomass. Good agreement of the model with the experimental data was obtained only after the glucoamylase diffusivity and the maximum specific glucose uptake rate were altered from their originally determined values. The model recognizes the distributed nature of the solid-state fermentation and therefore is able to predict the concentration profiles of the system components within the substrate. The model provides an insight into the possible rate-limiting steps in solid-state fermentation-the generation of glucose within the substrate and the resulting availability of glucose at the surface. 相似文献
36.
Sidney M. Greenfield 《Culture, medicine and psychiatry》1992,16(1):23-51
This paper examines the treatment of patients by a group of Spiritist healers in southern Brazil. After describing and analyzing a healing session, the practices are shown to be deviant from conventional Spiritism in two directions: (1) they employ a technique, called apometry, that they claim makes possible the transportation of a part of the patient's body to the astral world where it is treated by disincarnate doctors who do past life regressions; and (2) although a conventional Spiritist disobsession is performed, the healers invoke rival Afro-Brazilian spirits who often are shown to have caused the patient's symptoms.Building on the work of Csordas (1983), 1 hypothesize that the discourse employed by the healers moves the patient to a new reality or phenomenological world in which s/he is healed not in the sense of being restored to the state in which s/he existed prior to the onset of illness, but in the sense of being rhetorically moved into a state dissimilar from both pre-illness and illness reality... (Csordas 1983:346). The new state, in this case, is the world of Spiritism. Unlike the Catholic Pentecostals Csordas studied who already were members of a primary group of believers, however, the patients treated by the Brazilian healers are mostly unaffiliated individuals who face the increasing uncertainty and insecurity of life in disorganized, anomic, urban Brazil. By encompassing modern science on the one hand, and aspects of the Afro-Brazilian traditions on the other, this healing group appeals to the often distraught white middle and lower-middle classes, providing them with therapeutic meaning that in many cases leads to healing, conversion, and the sense of security and safety that often accompanies identifying with and belonging to a religious group. 相似文献
37.
Graham N. Stone Andy Purvis 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1992,162(3):284-295
Summary This study examines the relationship between warm-up rate, body mass, metabolic rate, thermal conductance and normothermic body temperature in heterothermic mammals during arousal from torpor. Predictions based on the assumption that the energetic cost of arousal has been minimised are tested using data for 35 species. The observation that across-species warm-up rate correlates negatively with body mass is confirmed using a comparative technique which removes confounding effects due to the non-independence of species data due to shared common ancestry. Mean warm-up rate during arousal correlates negatively with basal metabolic rate and positively with the temperature difference through which the animal warms, having controlled for other factors. These results suggest that selection has operated to minimise the overall energetic, cost of warm-up. In contrast, peak warm-up rate during arousal correlates positively with peak metabolic rate during arousal, and negatively with thermal conductance, when body mass has been taken into account. These results suggest that peak warm-up rate is more sensitive to the fundamental processes of heat generation and loss. Although heterothermic marsupials have lower normothermic body temperatures and basal metabolic rates, marsupials and heterothermic eutherian mammals do not differ systematically in warm-up rate. Pre-flight warm-up rates in one group of endothermic insects, the bees, are significantly higher than predictions based on rates of arousal of a mammal of the same body mass.Abbreviations BMR
basal metabolic rate
- ICM
independent comparisons method
- MWR
mean warm-up rate
- PMR
peak metabolic rate
- PWR
peak·warm-up rate
-
Tbactivity
body temperature during activity
-
Tbtorpor
body temperature during torpor
- T
arousal
increase in body temperature during arousal 相似文献
38.
Summary We report here an improved method for nuclei counting utilizing Triton-X 100 to reduce the size of cell debris, thereby allowing the use of a particle sizer/counter. Furthermore, nuclei are completely released within 30 seconds, as compared to 1 hour using hypotonic solution. The method is accurate above 0.3 × 106 cells/mL. 相似文献
39.
The araC regulatory gene mRNA contains a leader sequence 总被引:6,自引:0,他引:6
Laura G. Cass Arnold H. Horwitz C. Garrett Miyada Lawrence Greenfield Gary Wilcox 《Molecular & general genetics : MGG》1980,180(1):219-226
Summary An estimation of the size of the araC gene in Escherichia coli B/r was made by sub-cloning restriction fragments of the araC-containing hybrid plasmid pTB1 into the plasmid pBR322. Plasmids which contained a functional araC gene were identified by genetic complementation tests. DNA sequence analysis of the promoter-proximal region of the araC gene revealed that araC mRNA contains a 150 nucleotide leader. 相似文献
40.
Martin Poe Myra N. Williams Norma J. Greenfield Karst Hoogsteen 《Biochemical and biophysical research communications》1975,67(1):240-247
Proton magnetic resonance studies of 1:1 complexes of E. coli dihydrofolate reductase with folate and methotrexate were performed. A resonance at 1850 Hz in 1:1 enzyme-folate was assigned as the C-7 proton of bound folate by comparison with the spectra of enzyme complexed with folate specifically deuterated at C-7. The first order rate constant for folate dissociation was calculated to be less than 110 sec?1. Four of the five histidine residues exhibited the same pK's and chemical shifts in the two complexes with pK values of 8.0, 7.3, 6.5 and ~5. However, one histidine increased its pK by 0.7 units (6.25→6.95) and its C-2 proton resonance shifted upfield 50 Hz when folate was substituted for methotrexate. Comparison of these results with those of chemical modification and ultraviolet difference spectroscopy experiments suggests that this histidine may be in the folate binding site — possibly near the pteridine portion of that site. 相似文献