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1.
William S. Bowers Gopalan C. Unnithan Jun-Ichi Fukushima Jun Toda Takeyoshi Sugiyama 《Pest management science》1995,43(1):1-11
Twenty-one synthetic compounds, containing one or more furan rings, were demonstrated to possess anti-juvenile hormone (AJH) activity as evidenced by their induction of premature metamorphosis in the milkweed bug, Oncopeltus fasciatus (Dallas) by contact, topical application or fumigation. The ED50 of the four most active analogs required to induce precocious metamorphosis from 3rd-instar nymphs by residue contact in a Petri dish compared favorably with that of precocene II (6,7-dimethoxy-2,2-dimethyl 2H-chromene) a naturally occurring phytochemical AJH. Precocious metamorphosis was fully reversible by co-treatment with juvenile hormone (JH III) or JH analogs, demonstrating that the observed AJH activity resulted from an induced deficiency of juvenile hormone. 相似文献
2.
Rice plants cope with flash floods using either an ‘escape strategy’ involving rapid shoot elongation or a ‘quiescence strategy’ involving survival underwater with minimal activity. To clarify the differences in the response of leaf photosynthesis properties to conditions during and after submergence, two rice cultivars were compared: a non‐shoot‐elongating cultivar IR 67520‐B‐14‐1‐3‐2‐2 (IR67520) and a shoot‐elongating cultivar IR72442‐6B‐3‐2‐1‐1 (IR72442). Twenty‐three‐day‐old seedlings were submerged in 80‐cm‐deep water for 14 days. During submergence, the chlorophyll contents of the upper fully expanded leaf (5th leaf) and newly developed leaf later (6th leaf) and the maximal quantum yield of photosystem II (Fv/Fm) of the fifth leaf decreased earlier in IR72442 than in IR67520. In the submerged sixth leaf, Fv/Fm was higher in IR72442 than in IR67520 at early measurement. Although Fv/Fm of the sixth leaf in submerged IR67520 increased substantially from 2 days post‐submergence, IR72442 decreased because of leaf chlorosis. Therefore, a non‐shoot‐elongating cultivar coped with submergence by inhibiting photodamage and maintaining high chlorophyll content in the leaves. The shoot‐elongating cultivar was able to maintain the photosynthetic capacity of the newly developed leaf during submergence by prompt reduction of chlorophyll and chlorophyll fluorescence in the leaf that developed before submergence. 相似文献
3.
Ujihara T Taniguchi F Tanaka J Hayashi N 《Journal of agricultural and food chemistry》2011,59(5):1557-1564
To develop cleaved amplified polymorphic sequence (CAPS) markers for cultivar identification of the tea leaf, 5 primer pairs designed on the basis of genes that encode proteins related to nitrogen assimilation and 26 primer pairs based on expressed sequence tag (EST) sequences of the root of tea plant were screened. From combinations of primer pair and restriction enzyme that showed polymorphism among tea plants, 16 markers were selected and applied to DNA fingerprinting of Japanese tea cultivars. Sixty-three cultivars, except for a bud sport (Kiraka) and its original cultivar (Yabukita) and a pair that was the progeny of the same crossing parent (Harumoegi and Sakimidori), were distinguished from one another. By combining the 16 markers with previously developed CAPS markers and observing the physical appearance, 67 cultivars were distinguishable. The cultivars involve approximately 95% of total tea cultivating area in Japan; therefore, about 95% of tea leaves produced in Japan can be authenticated by labeling their cultivars. 相似文献
4.
Soil weathering is recognizable through study on physico-chemical characteristics of soil. In this study, Parker, ([(Na)a / 0.35] + [(Mg)a / 0.9] + [(K)a / 0.25] + [(Ca)a / 0.7]) × 100, and Product, [SiO2 / (TiO2 + Fe2O3 + SiO2 + Al2O3)] × 100, weathering indexes, originally developed for study on rocks, were tested on Yellow Brown Forest soils from two different regions in Japan. The results showed that the contribution of the mentioned indexes can be used for study on soils weathering. In other word, in a two-dimensional coordination system where the axes are Parker and Product indexes, regarding to the chemical bases of the indexes, initial and lateral products of weathering can be tracked at the same time.
Additionally, the indexes relations with soil color were studied after exposing the samples at a high temperature. Remarkable relationships between a* / b* ratio–parameters of psychometric chromaticness of color in CIE color standard system–and these two weathering indexes demonstrated that a* / b* ratio can be applied reliably to estimate the quantities of Parker and Product indexes in Yellow Brown Forest soils. 相似文献
5.
Yukiko ITO Ryuichi TATSUMI Jun-Ichi WAKAMATSU Takanori NISHIMURA Akihito HATTORI 《Animal Science Journal》2003,74(5):417-425
Myofibrillar proteins of vertebrate skeletal muscles are insoluble in solutions of ionic strength that approximate physiological conditions. We established a method to solubilize more than 80% of chicken breast muscle myofibrillar proteins in water for the use of meat as a source of food protein. SDS‐polyacrylamide gel electrophoretic patterns of water‐soluble myofibrillar proteins demonstrated that all identified myofibrillar proteins except connectin/titin were soluble in water. A part of α‐actinin was released from myofibrils by repeated washing with 2.5 mmol/L NaCl and 5 mmol/L L‐histidine solution, and subsequent destruction of connectin/titin in washed myofibrils by ultrasonication resulted in solubilization of a large fraction of chicken breast muscle myofibrillar proteins in water. Myofibrillar proteins of chicken leg, pork loin, beef shoulder loin, and lamb were also solubilized in water using this procedure. 相似文献
6.
Suto J Sekikawa K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(9):1039-1045
Body weight quantitative trait loci (QTLs), Bwq1 and Bwq2, identified previously in C57BL/6J x KK-Ay/a F2-Ay/a mice, were further confirmed and characterized. Body weight measurement was done from 21 days after birth (Day 21) through Day 100, at 10-day intervals. Bwq1 was statistically significant only on Days 40, 50, and 60, whereas Bwq2 was statistically significant on and after Day 40. When body weight gain (WG) between two successive weight measurements was evaluated, both Bwq1 and Bwq2 were statistically significant only for WG between Days 30 and 40. The results suggest that variations in body weight among F2-Ay/a individuals in later life have been determined by variations in WG during the period shortly after weaning. The results also suggest that Bwq1 is related to increased body weight in the KK strain, because the effect of Bwq1 on the body weight is observed not only in F2-Ay/a, but also in F2-a/a. On the other hand, it is suggested that Bwq2 is related to enhanced obesity caused by Ay mutation and therefore is a genetic modifier that specifically interacts with the Ay allele, because the effect of Bwq2 is only observed in F2-A y/a. There are two candidate genes, Pparg and Hrh1, which are located near the 95% confidence interval of Bwq2, and which are expressed in the adipose tissue; however, we could not find any nucleotide differences in both cDNAs between KK and C57BL/6J strains. 相似文献
7.
Suto J 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(8):1003-1006
Growth deficit (gd) is a recessive mutation that occurs spontaneously in the inbred NC/Sgn mouse strain. Because homozygotes (gd/gd) of both sexes are sterile, they must be produced by mating putative heterozygous carriers (+/gd) whose phenotypes are essentially the same as those of wild-type +/+ mice. The objectives of this study were to develop an efficient method that distinguished a gd allele from a wild-type allele and, if possible, to identify nucleotide substitutions responsible for the gd mutation. The location of the gd locus was estimated to be at 58.3 Mbp on chromosome 4, over which Musk is located. An A-to-G base substitution, which resulted in an M826V amino acid exchange, was identified within a tyrosine kinase domain of Musk. This base substitution disrupted a recognition site for NlaIII; this allowed for discriminating the gd allele from the wild-type allele using PCR-RFLP analysis. When 130 (C57BL/6J × NC/Sgn-gd) F(2) mice were genotyped by PCR-RFLP analysis, all 32 growth-retarded F(2) mice were judged to have the gd/gd genotype. Musk mutations are known to cause congenital myasthenia, which is accompanied by growth retardation, postnatal lethality, and development of a hunchback. These were the typical phenotypes of gd/gd mutants. Although we cannot rule out the possibility that the neighboring genes around the Musk locus are related to the gd phenotype, gd could possibly be classified as a mutant allele of Musk. 相似文献
8.
Sakagami N Umeki H Nishino O Uchiyama H Ichikawa K Takeshita K Kaneko E Akiyama K Kobayashi S Tamada H 《The Journal of reproduction and development》2012,58(1):140-146
The objective of this study was to examine whether high concentrations of epidermal growth factor (EGF) and/or insulin-like growth factor I (IGF-I) would have a beneficial effect on bovine embryo development in vitro and to obtain normal calves by using an ovum pick up method and embryo culture in a chemically defined medium. When compared with controls, EGF (100 or 200 ng/ml) or IGF-I (50 or 100 ng/ml) significantly increased the rate of embryos that developed into blastocysts during an 8-day culture after the in vitro fertilization of oocytes obtained from ovaries from a slaughterhouse. IGF-I induced a dose-dependent increase in cell number in both the inner cell mass and the trophectoderm, whereas EGF stimulated proliferation only in the inner cell mass. A combination of EGF (100 ng/ml) and IGF-I (50 ng/ml) produced an additive effect, and embryos developed into blastocysts at a comparatively high rate (27.9%) compared with controls (12.0%). A similar rate of development was achieved using a combination of EGF and IGF-I in the culture of embryos following ovum pick up by ultrasound-guided transvaginal follicular aspiration and in vitro fertilization, and 5 blastocysts that developed after the culture were transferred into uteri; two embryos implanted, and normal calves were born. These results suggest that the combined use of EGF and IGF-I makes bovine embryo culture in a chemically defined medium a practical and useful procedure for producing blastocysts, and its application to embryo culture following ovum pick up and in vitro fertilization could be useful for producing normal calves. 相似文献
9.
Effects of relative shoot height and irradiance on shoot and leaf properties of Quercus serrata Thunb. saplings growing in the understory and in gaps were investigated. Photosynthetic photon flux (PPF) at the location of the shoot relative to that in the open (relative PPF; rPPF) and the height of the shoot base relative to tree height (relative height; rHeight) were measured for all current-year shoots of each sapling. Current-year shoot properties (length, leaf area, number of daughter shoots) and mortality, and leaf properties (mass per area (LMA) and nitrogen content per area (N(area))) were examined in relation to rPPF and rHeight. N(area) was used as a proxy for area-based assimilative capacity. Shoot length, leaf area per shoot and number of daughter shoots increased with increasing rHeight, especially in well-lit conditions. Shoot mortality decreased with increasing rHeight and rPPF. Both LMA and N(area) were positively correlated with rPPF, but not rHeight. 相似文献
10.
Katsuji Uetake Shigeru Morita Nobutada Sakagami Kazuaki Yamamoto Shinji Hashimura Toshio Tanaka 《Animal Science Journal》2018,89(2):494-497
We compared the hair cortisol levels of lactating dairy cows in a cold‐ and a warm‐temperate region out of four climatic zones in Japan. We simultaneously investigated the effects of calving number, lactation period and month of hair sampling. Hair of nine Holstein lactating cows chosen from each region (i.e. 18 cows per sampling) was sampled in March, June, September and December. Number of calvings (1, 2, ≥3) and lactation duration (early: <100, middle: 101–200, and late: >201 days) were balanced between regions. Cortisol was extracted from hair by methanol, and its level was determined with a cortisol immunoassay kit. A multi‐way analysis of variance revealed that the effects of month of hair sampling (P < 0.001) and its combination with region (P < 0.05) were significant. In a multiple comparison test, significant differences (P < 0.01) in hair cortisol level (pg/mg of hair) were found between June (13.0 ± 1.0) and the other 3 months, and between September (1.6 ± 0.2) and December (4.5 ± 0.3). The rise in cortisol level from March to June was more intense in the cold‐temperate region. These results demonstrate the necessity of considering seasonal variations in each climatic region when we use hair cortisol level as an indicator of stress. 相似文献