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81.
82.
Sang-Nag Ahn Yeon-Kyu Kim Ha-Cheol Hong Seong-Sook Han Soo-Jin Kwon Hae-Chune Choi Huhn-Pal Moon Susan R. McCouch 《Euphytica》2000,116(1):17-22
A single dominant blast resistance gene conferring resistance to a Korean rice blast isolate was identified in rice variety
`Suweon 365'. We report the chromosomal localization and molecular mapping of this blast resistance gene designated as Pi-18, which confers resistance to Korean isolate `KI-313' of the blast pathogen. To know whether there is a relationship among
genes conditioning resistance to location-specific isolates of the blast pathogen and thereby to identify linked markers to
resistance gene for isolate KI-313 collected in Korea, RFLP markers previously reported to be linked to major blast resistance
genes in different rice germplasm and other markers mapped to nearby regions were surveyed for polymorphism between a resistant
(`Suweon 365') and a susceptible (`Chucheongbyeo') parent. Linkage associations of the RFLP markers with the resistance gene
were verified using an F2 and F3 segregating population of known blast reaction. RFLP analysis showed that Pi-18 was located near the end of chromosome 11, linked to a single copy clone RZ536 at a distance of 5.4 centiMorgans (cM) and
that this gene was different from Pi-1(t). An allelism test revealed that this gene was also different from Pi-k. Currently, a combination of RAPD and microsatellite primers is being employed to find additional markers in this region.
Tightly linked DNA markers will facilitate selection for resistant genotypes in breeding programs and provide the basis for
map based cloning of this new blast resistance gene.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
83.
84.
L J Smith P F Moon V M Lukasik H N Erb 《American journal of veterinary research》1999,60(9):1047-1050
OBJECTIVE: To describe onset and duration of neuromuscular blockade induced by mivacurium chloride and its associated hemodynamic effects at 3 dosages in healthy dogs. ANIMALS: 7 Labrador Retrievers. PROCEDURE: Anesthesia was induced with thiopental and maintained with halothane in oxygen, and dogs were mechanically ventilated to end-tidal P(CO)2 between 35 and 40 mm Hg. Core temperature, end-tidal P(CO)2, and halothane concentration were kept constant throughout the experiment. Neuromuscular function was assessed by evaluation of the train-of-four response to a supramaximal electrical stimulus of 2 Hz applied to the ulnar nerve every 10 seconds. Blood for determination of plasma cholinesterase activity was obtained prior to administration of mivacurium, a bolus of which was administered IV, using a randomized Latin-square design for dosages of 0.01, 0.02, and 0.05 mg/kg of body weight. RESULTS: All dogs had typical plasma cholinesterase activity. After administration of mivacurium, differences were not evident between groups in heart rate, systolic, mean, or diastolic blood pressure, change at any time in heart rate, systolic, mean, or diastolic blood pressure, or pH. Interval from onset to 100% neuromuscular blockade was 3.92+/-1.70, 2.42+/-0.53, and 1.63+/-0.25 minutes at dosages of 0.01, 0.02, and 0.05 mg/kg, respectively. Duration of measurable neuromuscular blockade was 33.72+/-12.73, 65.38+/-12.82, and 151.0+/-38.50 minutes, respectively. Time of onset and duration of effect differed significantly among dosages. CONCLUSIONS AND CLINICAL RELEVANCE: Mivacurium provides good hemodynamic stability at the dosages tested. In dogs, this drug has a rapid onset and long duration of effect. 相似文献
85.
Identification of a RAPD marker linked to a brown planthopper resistance gene in rice 总被引:12,自引:0,他引:12
We report the tagging of a brown planthopper (BPH) resistance gene (Bph–1) in rice using RAPD and RFLP markers. The Korean
rice variety ‘Gayabyeo’ has dominant duplicate genes including Bph–1 conferring resistance to biotype 1 of BPH. Bulked segregant
RAPD analysis was employed for rapid identification of DNA markers linked to resistance genes. For tagging these two genes,
an F2F3 population from a ‘Gayabyeo’ × ‘Nagdongbyeo’ cross was developed and evaluated for BPH resistance. Three bulked DNAs
from two groups of homozygous BPH resistant (each for Bph–1 and the other unknown gene) and homozygous susceptible F2 plants
were analyzed by RAPD using 140 random oligomers. One primer, OPD–7 yielded a 700-bp fragment that was present in Gayabyeo
and resistant F2 plants (homozygous for Bph-1 locus) but absent in Nagdongbyeo and susceptible F2 plants. Cosegregation of
this marker with Bph-1 was verified using an F2 population segregating for Bph-1. Chromosomal regions surrounding the Bph-1
were examined with additional RFLP and microsatellite markers on chromosome 12 to define the location of the RAPD marker and
Bph-1. Use of this RAPD marker could facilitate early selection of resistant lines for BPH.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
86.
Ji Hoon Moon Dong Hwa Chung Cheol-Ho Pan 《Journal Of Aquatic Food Product Technology》2017,26(10):1221-1232
Principal component analysis (PCA) and multiple linear regression (MLR) were conducted to characterize the drying of sea cucumber (SC). Far infrared radiation drying (FIRD) and hot air drying (AD) were used to dehydrate SC. Thirteen variables—including the morphological, color, and textural properties of dried SC—were selected for statistical analysis. The analysis of these 13 variables yielded three principal components showing significant correlations. PCA showed that the first three components represented 86.2% of the total variation. The first principal component was primarily related to the morphological properties of SC. The principal components determined by the PCA were more strongly influenced by the morphological variables than by the drying method. Of the morphological variables, the weight of SC had the strongest influence on the drying time and rehydration ratio of FIRD and AD. 相似文献
87.
Mung bean starch gels (8% solids) were prepared after annealing at 45–60°C for 1–24 hr, and the relationship between the physical properties of gels and the swelling power (SP) and solubility of starch was investigated. The SP and solubility decreased with increasing annealing temperature and time, mostly in the first 6 hr. The solubles were mainly composed of amylose. Gel hardness at a 5 mm depth of annealed starch was larger than that of native starch, and gel hardness increased as SP decreased (r = ‐0.94). Upon continued compression, the yield force of gel showed a different function. Above SP of ≈12.5, the yield force of annealed starch gels decreased, but at <12.5 the yield force increased with increasing SP. Both granular rigidity and extent of packing appeared to determine the yield force. Although annealing increased the gel hardness, α‐amylase digestibility of gel was not affected. Pasting analysis in the Rapid Visco Analyser (RVA) revealed that annealing increased pasting temperature. A pasting peak was found only in 45 and 50°C annealed starches. Overall paste viscosities of the starches annealed at >55°C were lower than that of the control starch. Final viscosities in RVA were correlated with the yield force of gel (r = 0.99). 相似文献
88.
Effect of cross-linking agent structure on the shape memory property of polyurethane block copolymer
Effect of cross-linking agent on the shape memory and mechanical property of polyurethane (PU) block copolymer is comprehensively
investigated. The selected chemical cross-linking agents are glycerol, 1,2,6-trihydroxyhexane, and 2,4,6-trihydroxybenzaldehyde
that are differentiated from each other in having remote hydroxyl group and aromatic ring. Significant increase in maximum
stress was observed for all of the cross-linked PUs, although the cross-linker structure was different. Structural change
of PU after cross-linking as evidenced by differential scanning calorimetry and infrared spectra was not detected, suggesting
that interaction between PU chains remained intact. Shape recovery went to as high as 95 % after cross-linking for all of
the cross-linking agents, and shape retention did not improve even if cross-linker was used. The remarkable increase in shape
recovery and maximum stress definitely originated from the employment of a cross-linking agent, and the effect of different
cross-linker structure on shape memory and mechanical property is discussed. 相似文献
89.
We attempted to determine whether weaning is required for induction of diarrhea in pigs with postweaning enterotoxigenic Escherichia coli infection. Three-week-old newly weaned pigs and their suckling littermates were inoculated with the K88+ enterotoxigenic E coli strain M1823B. Fourteen of 21 weaned and 12 of 20 suckling pigs were genetically resistant to intestinal adhesion by the K88+ strain of E coli; they remained healthy, and gained weight at similar rates. Both groups of K88-resistant pigs gained weight faster, and shed fewer bacteria of strain M1823B in their feces, than did their K88-susceptible counterparts. Diarrhea developed in K88-susceptible pigs in the weaned (6 of 7 pigs) and suckling (4 of 8 pigs) groups, and 1 of the 4 affected suckling pigs died from complications resulting from diarrhea. The incidences of diarrhea, weight gain rates, and the numbers of strain M1823B shed in feces of susceptible weaned and suckling pigs were not significantly (P greater than 0.05) different. Diarrhea scores of susceptible weaned pigs were significantly (P less than 0.02) higher than those of susceptible suckling pigs on the second day after inoculation. In this experimental model, it was concluded that weaning is not required for induction of diarrhea, but may modestly increase its severity. 相似文献
90.
Primigravid swine were vaccinated orally with a live enterotoxigenic Escherichia coli (ETEC) strain that produces pilus antigen K99. The titers of K99 antibody in colostrum and milk of vaccinates remained higher than those of nonvaccinated controls through the first lactation after vaccination (4 weeks). Some control swine had low titers of K99 antibody in colostrum or developed low titers of K99 antibody in milk during lactation. Lacteal K99 antibody titers of vaccinates dropped to control levels during the second lactation, 6 months after vaccination. Pigs suckling vaccinates and controls were equally susceptible to challenge exposure to K99+ ETEC during the second lactation. Orally vaccinated swine given a parenteral booster vaccination (with killed K99+ ETEC) during their second gestation had K99 antibody in milk through their second lactation. During the second lactation, these orally vaccinated parenterally revaccinated swine had higher titers of K99 antibody in postcolostral milk than did nonvaccinated controls, controls given only the parenteral booster injection, or controls vaccinated parenterally during both gestations. 相似文献