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1.
Putranto HD Kusuda S Inagaki K Kumagai G Ishii-Tamura R Uziie Y Doi O 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(5):569-571
Feces were collected from two female and one male Siberian tigers, Panthera tigris altaica. Steroid hormones were extracted from lyophilized feces and quantified by enzyme immunoassay. The fecal contents of estradiol-17beta (E(2)) and testosterone in the females and male, respectively, changed markedly throughout the year. The fecal E(2) contents of females Nos. 179 and 238 increased at 26.4 +/- 8.0 and 28.0 +/- 14.2 day intervals, respectively. However, the fecal contents of progesterone (P(4)) in the female kept alone did not change. In contrast, the other female, which was kept with a male, had increased fecal P(4) contents after copulation. The fecal progesterone levels of the pregnant female remained high during her 106-day pregnancy. 相似文献
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Takashi Masaki Shigeta Mori Takuya Kajimoto Gaku Hitsuma Satoshi Sawata Masuo Mori Katsuhiro Osumi Shobu Sakurai Takeshi Seki 《Journal of Forest Research》2006,11(4):217-225
The individual growth of tree diameter at breast height (dbh) is analyzed in an even-aged plantation of Cryptomeria japonica from stand age of 45 to 94 years, to examine how the growth of individual trees has been affected by the changes in spacing
resulting from thinning operations. At any age, a significant proportion (0.37–0.46) of the variation in dbh growth during
a 5–11-year period was explained by dbh at the beginning of the period, probably due to greater leaf mass of larger trees.
Next, either one-sided or two-sided competition was added to the model, by calculating the basal area (BA) of neighboring
trees around each tree within a given radius or BA for trees having larger dbh than the focal tree within the radius. After
preliminary analyses, a radius of 8 m was selected as the critical range for tree competition. Although both types of competition
explained a significant proportion (0.09–0.43) of growth variation, one-sided competition was not significant at ages greater
than 54 years. Based on the model at 45 years of age, the initial deviation of growth rate for each tree from the predicted
rate was calculated and added to the models as a third variable. This raised the coefficient of determination up to 0.50–0.74.
These findings have practical significance for forest plantation management, particularly for controlling the growth of standing
trees via thinning, to produce high-quality timber in the future. 相似文献
4.
Tsuboi M Etoh H Kato K Nakatugawa H Kato H Maejima Y Matsumoto G Mori H Hosokawa M Miyashita K Tokuda H Suzuki N Maoka T 《Journal of agricultural and food chemistry》2011,59(19):10572-10578
The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN). 相似文献
5.
Gaku Kanno Takahito Yamaguchi Hideki Kishimura Etsurou Yamaha Hiroki Saeki 《Fish physiology and biochemistry》2010,36(3):637-645
Trypsin from the pyloric ceca of masu salmon (Oncorhynchus masou) cultured in fresh water was purified by a series of chromatographies including Sephacryl S-200, Sephadex G-50 and diethylaminoethyl
cellulose to obtain a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS–PAGE) and native PAGE.
The molecular mass of the purified trypsin was estimated to be approximately 24,000 Da by SDS–PAGE. The enzyme activity was
strongly inhibited by phenylmethylsulfonyl fluoride, soybean trypsin inhibitor, and N
α
-p-tosyl-l-lysine chloromethyl ketone. Masu salmon trypsin was stabilized by calcium ion. The optimum pH of the masu salmon trypsin
was around pH 8.5, and the trypsin was unstable below pH 5.0. The optimum temperature of the masu salmon trypsin was around
60°C, and the trypsin was stable below 50°C, like temperate-zone and tropical-zone fish trypsins. The N-terminal 20 amino acid sequence of the masu salmon trypsin was IVGGYECKAYSQPHQVSLNS, and its charged amino acid content was
lower than those of trypsins from frigid-zone fish and similar to those of trypsins from temperate-zone and tropical-zone
fish. In the phylogenetic tree, the masu salmon trypsin was classified into the group of the temperate-zone fish trypsin. 相似文献
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Reef-building corals are sensitive to excessive nitrogenous (N) compounds. To maintain levels of inorganic nitrogenous compounds low in coral aquaria, various technologies, mechanical, chemical and biological, have been applied. As one of the biological techniques, “live rock,” which can be defined as a dead coral skeleton covered with crustose coralline algae (CCA), has long been applied for coral aquaria. Until recently, however, there has been little evidence for the effectiveness of live rock in removal of N compounds from coral aquaria. Demonstrating comparative experiments with live rocks, here we report that the live rock is capable of removing N compounds and reduces the mortality of reef-building coral. We cultured the reef-building coral Acropora digitifera with the sea cucumber Holothuria atra as a natural nitrogen producer. H. atra increased the concentration of the inorganic N compounds (NH4+, NO3− and NO2−) that resulted in high coral mortality. The presence of the live rock remarkably reduced the concentrations and sustained a high coral photosynthetic activity. We detected the functional genes amoA and nirS within the live rock, suggesting the occurrence of both nitrifying and denitrifying bacteria. These results support the idea that “live rock” is an effective biofilter that can maintain water quality suitable for reef-building corals. 相似文献
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Takuya Kajimoto Gaku Hitsuma Takashi Masaki Tatsuo Kanazashi 《Journal of Forest Research》2006,11(2):107-116
We analyzed the growth patterns of Thujopsis dolabrata var. hondai trees in an old plantation (161 years old), where no silvicultural treatments (e.g., thinning) have been conducted since
the initial planting. The analysis focused on understanding individual growth under a long-term self-thinning process, and
the stand-level stemwood production at the mature stage was evaluated. Nine canopy-layer trees and one suppressed tree were
used for the analysis of annual increments in stem diameters, heights, and stemwood volumes for a given past year using the
ring-width data. Both the diameter (at basal portion) and height of all the canopy-layer trees increased at similar rates
during the early stage (i.e., 60–70 years after planting); however, after this period, only the height growth rates declined
sharply. The annual growth rates of stemwood volume also simultaneously leveled off at the stand age of 40–60 years. Subsequently,
the patterns diverged conspicuously, e.g., the growth rates were maintained or increased in some individuals, while it gradually
decreased in the case of others until the present year. The divergence of growth pattern was likely to be triggered by intertree
competition at several decades after the onset of canopy closure. The current stemwood production of the sample trees, including
the suppressed one, was positively correlated with certain size parameters such as stem diameter at breast height and sapwood
area at a height of 4 m. Based on the diameter-base allometry, the total stand stemwood production was estimated to be about
12.8 m3 ha−1 year−1. This estimate was higher than those of some old natural T. dolabrata forests (2.0–8.6 m3 ha−1 year−1) that have been well managed by repetitive selection thinning. Furthermore, individual mean stemwood production of the study
plantation (0.03 m3 tree−1 year−1) was within the range of these natural stands (0.01–0.05 m3 tree−1 year−1). These comparisons suggested that the old T. dolabrata plantation still maintained a relatively high stemwood production potential despite the absence of artificial controls of
tree density in the past. In terms of timber production, this fact implied that a rather long rotation (>100 years) can be
applicable in the management of T. dolabrata plantations. 相似文献
8.
Journal of General Plant Pathology - In 2017 and 2018, corky root disease was observed on lettuce (Lactuca sativa L.) in Nagano Prefecture, Japan. The symptoms included corky, brittle, dark-brown... 相似文献
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Yoshida K Yokoyama H Oteki T Matsumoto G Aizawa K Inakuma T 《Journal of agricultural and food chemistry》2011,59(7):2966-2971
Although it has been reported that dietary lycopene, the main carotenoid in tomato, improved drug-induced nephropathy, there are no reports on the effect of orally administered lycopene on the in vivo renal reducing (i.e., antioxidant) ability. The radiofrequency electron paramagnetic resonance (EPR) method is a unique technique by which the in vivo reducing ability of an experimental animal can be studied. In this study, the in vivo changes in the renal reducing ability of rats orally administered lycopene were investigated using a 700 MHz EPR spectrometer equipped with a surface-coil-type resonator. Rats were fed either a control diet or a diet containing lycopene. After 2 weeks, in vivo EPR measurements were conducted. The renal reducing ability of lycopene-treated rats was significantly greater than that of the control. This is the first verification of in vivo antioxidant enhancement via dietary lycopene administration. 相似文献
10.
Ai Fujita Masaru Hojo Tetsuo Aoyagi Yoshinobu Hayashi Gaku Arakawa Gaku Tokuda Hirofumi Watanabe 《Journal of Wood Science》2010,56(3):222-226
Wood-feeding termites have evolved an efficient cellulose-decomposing system. The termite has two independent cellulose-digesting
systems: one in the midgut and the other in the hindgut. Because the digestion system in the midgut should be the sole source
of soluble sugars for the host termite, the details of the decomposition of wood particles in the midgut were clarified in
one of the most common pest species, Coptotermes formosanus. The spatial distribution of cellulase in the midgut was found by immunohistochemistry, and the amount of endogenous cellulases
and the volume of the endoperitrophic space were determined. The size of wood particles in the foregut and the midgut were
compared. The results showed that one of the characteristics of wood degradation by termites is the mechanical grinding of
food by the mandibles and the cuticular apparatus of the foregut. This process greatly increases the surface area of the substrates.
Extremely high concentrations of cellulase attack the ground-up wood in the midgut, and the glucose produced is removed quickly
through the peritrophic membrane. 相似文献