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151.
Fukanoki SI Matsumoto K Mori H Takeda R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(8):917-919
Water-in-oil emulsions containing bovine serum albumin (BSA) as a model antigen were prepared using aliphatic saturated hydrocarbons with carbon number from 12 to 18, and were tested in chickens. Straight-chain hydrocarbons induced higher antibody titers against BSA after administration than branched-chain hydrocarbons. n-C16H34 and n-C18H38 maintained high antibody titers even at 32 weeks after administration, compared with n-C12H26, n-C14H30 and n-C15H32. n-C12H26 and n-C14H30 raised concentrations of sialic acid and creatine kinase in plasma, both of which are important markers of inflammatory responses, immediately after administration. n-C16H34 and n-C18H38 did not raise the values of these markers. These results indicated that n-C16H34 and n-C18H38 induced elevated and sustained immune responses without severe adverse reactions in chickens. 相似文献
152.
GhCesA2 is a cotton (Gossypium hirsutum) homologue of the bacterial cellulose synthase gene that encodes cellulose 4--glucosyltransferase. The central catalytic region of GhCesA2 was expressed as a soluble protein in the methylotrophic yeastPichia pastoris. The molecular size of the recombinant protein was 100kDa, which decreased to 85 kDa after treatment with endoglycosidase H. The recombinant GhCesA2 catalyzed transfer of glucose from UDP-glucose into unknown products in the presence of an extract of cotton hypocotyls, but the products were not-1,4-glucan. 相似文献
153.
Allometry of shoot extension units (hereafter termed "current shoots") was analyzed in a Malaysian canopy species, Elateriospermum tapos Bl. (Euphorbiaceae). Changes in current shoot allometry with increasing tree height were related to growth and maintenance of tree crowns. Total biomass, biomass allocation ratio of non-photosynthetic to photosynthetic organs, and wood density of current shoots were unrelated to tree height. However, shoot structure changed with tree height. Compared with short trees, tall trees produced current shoots of the same mass but with thicker and shorter stems. Current shoots with thin and long stems enhanced height growth in short trees, whereas in tall trees, thick and short current shoots may reduce mechanical and hydraulic stresses. Furthermore, compared with short trees, tall trees produced current shoots with more leaves of lower dry mass, smaller area, and smaller specific leaf area (SLA). Short trees adapted to low light flux density by reducing mutual shading with large leaves having a large SLA. In contrast, tall trees reduced mutual shading within a shoot by producing more small leaves in distal than in proximal parts of the shoot stem. The production of a large number of small leaves promoted light penetration into the dense crowns of tall trees. All of these characteristics suggest that the change in current shoot structure with increasing tree height is adaptive in E. tapos, enabling short trees to maximize height growth and tall trees to maximize light capture. 相似文献
154.
Potassium,calcium, and magnesium dynamics during litter decomposition in a cool temperate forest 总被引:3,自引:0,他引:3
The dynamics of K, Ca, and Mg were investigated during the decomposition of 14 litter types over a 3-year period on the upper and lower parts of a forest slope in a cool temperate forest in Japan. Potassium dynamics were divided into initial leaching phase and late phase. Initial K concentrations for the initial phase were correlated with the rate of decrease in K concentration during the initial phase. The late phase was characterized by seasonal fluctuations in concentration: K concentration increased from April to November and decreased during the winter period. The pattern of change in Ca concentration was divided into initial increase phase and late decrease phase in some litter types, or consisted of the late phase only in other litters. Calcium concentration of the initial litter was not predictable for the pattern of change in Ca concentration nor the rate of change in Ca concentration during the initial phase. Initial Ca concentration for the late phase was correlated with the rate of change in Ca concentration during the late phase. The pattern of change in Mg concentration was divided into initial leaching phase and late immobilization phase. Initial Mg concentration for the initial phase was correlated with the rate of change in Mg concentration during the initial phase. At the lower site, initial Mg concentration for the late phase was correlated with the rate of change in Mg concentration during the late phase, while such a relationship was not observed at the upper site. Concentrations of K, Ca, and Mg showed a convergent trend at the end of the study period. The final concentration differed between the upper and lower sites. 相似文献
155.
This study quantitatively compared the sapling (height 62–289cm) architecture and growth of Castanopsis cuspidata and Quercus glauca, both of which are major components in the temperate zone of western Japan, under shaded light conditions in secondary forest. When the sapling architectures were compared at the same support mass (trunk + branch mass), C. cuspidata had a larger crown area but a smaller height gain than did Q. glauca owing to the allocation of more biomass to lateral branches in C. cuspidata. The above-ground relative growth rate (RGR) of C. cuspidata (0.442gg–1 year–1) was nearly twice that of Q. glauca (0.256gg–1year–1), primarily as a result of a greater total leaf area per above-ground biomass (LAR) in C. cuspidata (56cm2g–1) as compared to Q. glauca (33cm2g–1). Because it has a disadvantage in height gain, related to its allocation pattern of biomass, C. cuspidata realized the same height growth (RGRH) as Q. glauca, despite the large biomass production. The great potential for photosynthesis in C. cuspidata, which results from its vigorous lateral spreading, is presumed to give it a long-term advantage over Q. glauca in the shaded forest understory. Q. glauca invests preferentially in trunk biomass, possibly giving it an advantage in sunny sites as opposed to a shaded forest understory. 相似文献
156.
The suitability of a color acetate film for estimating photosynthetic photon flux density (PPFD) in a forest understory was examined. The fading ratio of the film (F), the total PPFD (PPFDtotal) to which the film was exposed, and the average daily maximum temperature during exposure (T) were obtained from measurements at multiple sampling points throughout an entire year within a natural secondary forest (n = 42). The ranges of the recorded values were as follows: F 35%–99%, PPFDtotal 1.4–28.3molm–2, and T 6°–32°C. PPFDtotal was regressed by F and T with a high r
2 (=0.94; P < 0.0001): PPFDtotal = (100 – F)/(1.085 + 0.051T). The absolute error (|estimated PPFDtotal – measured PPFDtotal|) averaged 1.3molm–2 with a maximum of 5.7molm–2, indicating a good fit. These results indicated broad applicability of the film, both spatially and temporally, for estimating forest understory PPFD. 相似文献
157.
158.
Mitsuhiro Ichinari Michio Masuko Hideyuki Takenaka Riichi Hasegawa Tsuneo Ichiba Yoshio Hayase Reiji Takeda 《Pest management science》1999,55(9):962-962
The original article to which this Correction refers was published in Pesticide Science 55 (3) 1999, 347–349. © 1999 Society of Chemical Industry 相似文献
159.
Three insect-neuroactive substances from Liquidamber styraciflua and L formosana were isolated and characterized by spectral analyses as betulonic acid, 1-methoxy-9-caryolanol and eudesm-4(14)-ene-1,6-diol, respectively. ©1999 Society of Chemical Industry 相似文献
160.
The pattern of changes in the physicochemical properties of wood, and its relationship with fungal succession during decomposition
of coarse woody debris (CWD) of beech (Fagus crenata Blume) were investigated. In total, 47 snags and 66 logs were assigned to a system of five decay classes, and were used for
analysis of the decomposition process. The decomposition process consists of two phases characterized by their dominant organic
chemical constituents. In the first phase (decay class 1–3), acid-unhydrolyzable residue (AUR) and holocellulose decreased
simultaneously. In the second phase (decay class 3–5), holocellulose decayed selectively. Fruiting bodies of ten fungal taxa
occurred frequently on decomposing logs and/or snags. These fungi were divided into early and late colonizers according to
their occurrence during CWD decomposition. The relationship between fungal community composition and the physicochemical properties
of CWD was analyzed by canonical correspondence analysis (CCA). According to the Monte Carlo permutation test, decay class,
water content, and type of CWD (log or snag) significantly affected the fungal community structure. Our results suggested
that white-rot basidiomycetes, especially Omphalotus guepiniformis, play a central role in the simultaneous decomposition of AUR and holocellulose in the first phase of decomposition. On the
other hand, fungal taxa occurring in the second phase of decomposition may not be responsible for the decomposition of holocellulose.
Three possible mechanisms of holocellulose decomposition and AUR accumulation in the second phase of decomposition are proposed
and discussed.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献