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91.
The genotypes of photoperiod response genes Ppd-B1 and Ppd-D1 in Japanese wheat cultivars were determined by a PCR-based method, and heading times were compared among genotypes. Most of the Japanese wheat cultivars, except those from the Hokkaido region, carried the photoperiod-insensitive allele Ppd-D1a, and heading was accelerated 10.3 days compared with the Ppd-D1b genotype. Early cultivars with Ppd-D1a may have been selected to avoid damage from preharvest rain. In the Hokkaido region, Ppd-D1a frequency was lower and heading date was late regardless of Ppd-D1 genotype, suggesting another genetic mechanism for late heading in Hokkaido cultivars. In this study, only 11 cultivars proved to carry Ppd-B1a, and all of them carried another photoperiod-insensitive allele, Ppd-D1a. The Ppd-B1a/Ppd-D1a genotype headed 6.7 days earlier than the Ppd-B1b/Ppd-D1a genotype, indicating a significant effect of Ppd-B1a in the genetic background with Ppd-D1a. Early-maturity breeding in Japan is believed to be accelerated by the introduction of the Ppd-B1a allele into medium-heading cultivars carrying Ppd-D1a. Pedigree analysis showed that Ppd-B1a in three extra-early commercial cultivars was inherited from ‘Shiroboro 21’ by early-heading Chugoku lines bred at the Chugoku Agriculture Experimental Station.  相似文献   
92.
Colletotrichum orbiculare (syn. C. lagenarium) is the causal agent of anthracnose disease on cucurbit plants. This fungus forms dome-shaped, melanized appressoria as a host invasion structure. Strain 104-T (MAFF240422) of C. orbiculare, which was originally isolated from a cucumber plant in 1951 by Dr. Yasumori, Kyoto University, has proven to be an excellent experimental model for the study of fungal pathogenesis and morphogenesis because of its stable pathogenicity and synchronous infection-related morphogenesis. This review considers the discoveries made during 60 years of study on C. orbiculare. In particular, we focus on advances made in the last two decades, which have provided a basis for the molecular analysis not only of fungal morphogenesis, but also of plant–microbe interactions, including plant immunity to adapted and nonadapted Colletotrichum fungi. This substantial body of innovative research was originated by the Phytopathological Society of Japan and represents a major contribution to the international research communities working on plant pathology, plant–microbe interactions, and fungal molecular genetics. This review deals with the past achievements and future prospects in the study of Colletotrichum biology, focusing on the molecular genetics of C. orbiculare with regard to four aspects: (1) metabolic and functional development of infection structures, (2) signaling pathways required for fungal pathogenesis, (3) pathogen-associated molecular patterns (PAMPs) and host basal resistance, and (4) establishment of host specificity.  相似文献   
93.
Rheological experiments on fine-grained water ice II at low strain rates reveal a creep mechanism that dominates at conditions of low stress. Using cryogenic scanning electron microscopy, we observed that a change in stress exponent from 5 to 2.5 correlates strongly with a decrease in grain size from about 40 to 6 micrometers. The grain size-sensitive creep of ice II demonstrated here plausibly dominates plastic strain at the low-stress conditions in the interior of medium- to large-sized icy moons of the outer solar system.  相似文献   
94.
SUMMARY: Atka mackerel (Am) and Japanese common squid (Sq) meats were cured in 0.5–1.5 M sorbitol solutions (pH 7.0) and dried at 30°C (relative humidity, 60%), and the effect of sorbitol on the moisture transportation and textural change during the curing and drying processes was investigated. With an increase in sorbitol permeated through samples, the moisture contents decreased by 52% (Am) and 42% (Sq) by curing in 1.5 M sorbitol solution. When the cured meats were dried, slow moisture vaporization occurred at the initial drying period, and the critical moisture content significantly decreased with an increase in the sorbitol content of the cured meats. Further, the hardening of the dried products was effectively suppressed by sorbitol curing. These effects of sorbitol would contribute to the reduction of drying time and particularly the elimination of the excess hardening of dried fish products.  相似文献   
95.
A series of alkyl 3,4-dihydroxybenzoates (protocatechuates) was synthesized, and their fungicidal activity against Saccharomyces cerevisiae was assayed using a 2-fold serial broth dilution method. Nonyl and octyl 3,4-dihydroxybenzoate were noted to be the most effective against this yeast with the minimum fungicidal concentration of 12.5 microg/mL each. The activity was found to correlate with the hydrophobic alkyl chain length. The time-kill curve study showed that nonyl 3,4-dihydroxybenzoate was fungicidal against S. cerevisiae at any growth stage and this activity was not influenced by pH values. The fungicidal activity of alkyl 3,4-dihydroxybenzoates was noted in combination with their ability to disrupt the native membrane-associated function nonspecifically as surface-active agents (surfactants) and to inhibit the respiratory electron transport. However, the primary fungicidal activity of nonyl 3,4-dihydroxybenzoate likely comes from its ability to act as a surfactant.  相似文献   
96.
The objectives of this study were to establish and characterize a homologous immunoassay for bovine chromogranin A (bCgA) and to profile plasma bCgA concentrations during early pregnancies. We synthesized oligopeptide corresponding to the amino acid sequence 341–355 of bCgA for immunizing rabbits and peptide corresponding to the amino acid sequence 336–365 of bCgA for both a biotinylated tracer and reference standards. Recombinant bCgA protein was also generated in Escherichia coli lysate. Dose-dependent displacement curves were obtained from 1 to 1,000 nM of the reference standards. The displacement curves showed a good relationship between the reference standards of the synthetic peptide and the serially diluted plasma sample or recombinant bCgA protein generated in the present study. The assay sensitivity defined as the value of two standard deviations below the zero standard was calculated as 0.46 nM. The intraassay and interassay coefficients of variation were 6.48% and 13.4%, respectively. Changes in the plasma bCgA concentrations in early pregnancies undulated in nonpregnant animals. The results of the present study suggest that assaying plasma bCgA concentrations could be utilized as measures to evaluate the physiological status of cattle.  相似文献   
97.
For obtaining the preliminary data on the pathogenesis of sudden death in calves naturally heavily infected with Strongyloides papillosus, we monitored 8 Holstein calves experimentally infected with the larvae on electrocardiographic and pneumographic changes. Six calves died suddenly on days 11 to 17 after infection. Sinus tachycardia had been recorded continuously since 1 to 6 days before death. Heart rates increased gradually until death. Since 1 or 2 days before death, various patterns of tachyarrhythmia and bradyarrhythmia had been observed among patterns of sinus tachycardia. Arrhythmias included serious ventricular premature beat, paroxysmal ventricular tachycardia, complete atrioventricular block and so on. The terminal pattern observed suddenly in all of the cases was ventricular arrhythmias consisting of serial ventricular tachycardia, flutter and fibrillation, which were followed by respiratory arrest. Abnormal pneumograms were not obtained before the terminal ventricular fibrillation. Two of 8 calves recovered from the infection, only one of which showed sinus arrest and the second degree of atrioventricular block transiently. We concluded that calves heavily infected with the larvae died due to sudden cardiac arrest.  相似文献   
98.
Anthocyanin synthesis began in the skin of ‘Olympia’ (Vitis labruscana Bailey) grape when the berry growth reached a late stage in the second sigmoid growth-curve. During berry development, shikimate NADP oxidoreductase (SORase, EC.1.1.1.25), phenylalanine ammonia-lyase (PAL, EC.4.3.1.5), and chalcone flavanone isomerase (CHFI, EC.5.5.1.6) were investigated in the skin. These enzyme activities were high during early development of the young berry, but rapidly decreased thereafter, and were activated again when rapid anthocyanin synthesis subsequently occurred. When PAL from the young berry was analyzed by isoelectricfocusing polyacrylamide gel electrophoresis (IEF-PAGE), it showed a single activity band with a pI value of approximately 5.4, whereas PAL from the ripe berry showed two activity bands with pIs of 5.4 and 6.5. Thus, SORase, PAL, and CHFI seem to be involved in anthocyanin accumulation simultaneously, and newly synthesized isozyme of PAL may play a key role in pigment formation in ‘Olympia’ skin. The function of these enzyme activities in young berry is also discussed in this text.  相似文献   
99.
Polycrystalline (Mg(0.9),Fe(0.1))SiO3 post-perovskite was plastically deformed in the diamond anvil cell between 145 and 157 gigapascals. The lattice-preferred orientations obtained in the sample suggest that slip on planes near (100) and (110) dominate plastic deformation under these conditions. Assuming similar behavior at lower mantle conditions, we simulated plastic strains and the contribution of post-perovskite to anisotropy in the D' region at the Earth core-mantle boundary using numerical convection and viscoplastic polycrystal plasticity models. We find a significant depth dependence of the anisotropy that only develops near and beyond the turning point of a downwelling slab. Our calculated anisotropies are strongly dependent on the choice of elastic moduli and remain hard to reconcile with seismic observations.  相似文献   
100.
In B6AF1 mice, T lymphocytes that use the V beta 11-positive (and not V beta 6-positive or V beta 8-positive) segment in their receptor for antigen are greatly reduced in the thymus and peripheral lymphoid tissues, most likely as a result of clonal deletion. The relative number of V beta 11-positive cells in adult lymph nodes was ten times as high in B6AF1 mice thymectomized 1 to 4 days after birth as in normal mice. Moreover, for the first 10 days of life of B6AF1 mice, mature V beta 11-positive T cells were readily detected in the thymus and spleen. Thus neonatal thymectomy results in the maintenance of the receptor repertoire of early postnatal life, and this correlates with the subsequent development of organ-specific autoimmune diseases.  相似文献   
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