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1.
It is well known that some caspases in apoptosis is involved in determinant of terminal differentiation and maturation of various cells. Our previous study ultrastructurally clarified the differentiation into M cells from immature microvillous epithelial cells and the redifferentiation from M cells to microvillous epithelial cells in the follicle-associated epithelium (FAE) of rat Peyer's patch. In this study, the difference of epithelial apoptosis between the FAE of Peyer's patch and intestinal villi was immunohistochemically investigated in rat jejunoileum. As a result, cleaved caspase-3 was limited to several epithelial cells at the tip of FAE, whereas almost all of the epithelial cells were cleaved caspase-3 positive in intestinal villi. Cleaved caspase-9 was detected only in a few exfoliating or exfoliated epithelial cells of both FAE and intestinal villi. Nuclear DNA-fragmentation was detected only in several epithelial cells of the tip of FAE, while it was expressed from the middle regions in the intestinal villi. The DNase I expression of the epithelial cytoplasm was much weaker in FAE than in intestinal villi. Bcl-x expression was restricted in the apical cytoplasms of epithelial cells in the FAE, whereas it was restricted in whole cytoplasms in villous epithelial cells. These findings suggest that the progression of the apoptotic process in the epithelial cells of FAE is later than in the intestinal villi, so that the possibility of epithelial differentiation might be remained in the FAE, unlike in the intestinal villi.  相似文献   
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The effect of diniconazole, an inhibitor of cytochrome P450, on drought tolerance was examined in ‘Shiranui’ [(Citrus unshiu Marc. × Citrus unshiu Osbeck) × Citrus reticulate Blanco] trees. Diniconazole treatment increased abscisic acid (ABA) concentration in leaves compared with untreated controls in water-stressed conditions after 20 days of water-stress treatment. Diniconazole significantly decreased the stomatal aperture at 9 h after application compared with untreated controls in water-stressed conditions. The photosynthetic rate decreased in water-stressed conditions; however, regardless of the earlier stomatal closure induced by diniconazole application, the decrease of photosynthetic rate was delayed by the application.  相似文献   
4.
This study investigated the effect of different light intensities on feeding, growth and survival of early stage leopard coral grouper Plectropomus leopardus larvae. Four different light intensities (0, 500, 1000 and 3000 lx) were used and larvae were kept under constant light conditions from 0 day after hatching (DAH) to 5 DAH. The larvae were fed a small S-type of Thai strain rotifers at a density of 20 individuals/mL from 2 DAH. The number of rotifers in larval digestive organ and total length of larvae were examined at 3 h intervals between 04:00 and 22:00 h on 3 DAH, and thereafter at 6 h intervals until the end of the experiment (5 DAH). Four experimental trials of the larval rearing were repeated using by 60 kL mass-scale rearing tanks. The results indicate that coral grouper larvae are visual feeders and their food intake increases with increasing light intensity. Food intake of larvae reared at 3000 lx was significantly higher than those reared at 0–1000 lx on 3 DAH despite being the first-feeding day (< 0.01). On 4 DAH, total length of larvae reared at 3000 lx was significantly larger than those reared at the lower light intensities (0, 500 and 1000 lx), and thereafter light intensity significantly influenced larval feeding and growth until the end of the experiment. Survival on 5 DAH did not show a significant difference between light intensities, but survival rate at 3000 lx and 1000 lx had a tendency to be higher than those reared at the lower light intensities (0 and 500 lx). In contrast, larvae reared at 0 lx exhibited stagnant and/or negative growth. These results indicate that light intensity is significantly the factor affecting larval feeding, growth, and survival in coral grouper larvae under the rearing conditions.  相似文献   
5.
The protected structure of -oxoacteoside (tomentoside A), 2-oxo-2-(3,4-dihydroxyphenyl)ethyl 3-O-(2,3,4-tri-O-acetyl--l-rhamnopyranosyl)-4-O-caffeoyl--d-glucopyranoside 14 was synthesized in 14% overall yield in 11 steps, starting from d-glucose for biological and medicinal studies of phenylpropanoid glycosides. The first step was the preparation of a 3-O-rhamnopyranosyl disaccharide sugar core 2 from a suitably protected rhamnosyl trichloroacetimidate 10 and glucose derivative (diacetone-d-glucose 1) in 71% yield. To the glucose moiety of this sugar core, several protection/deprotection procedures were performed sequentially to obtain a fully acetylated sugar core 7 with a 4-OH group on the glucose moiety, in 57% yield in five steps. Thereafter, to the 4-OH group of the glucose moiety, selective 4-O-caffeoylation was achieved by proton-transfer esterification with 3,4-di-O-allylcaffeic acid 16 to give the caffeoyl disaccharide 11 in 97% yield. Then, it was converted to trichloroacetimidate 13 for a glycosylation donor in 90% in two steps. Finally, anomeric glycosylation was conducted with 2-oxo-2-(3,4-di-allyloxyphenyl)ethyl alcohol 19 with catalytic amounts of BF3·Et2O to give 2-oxo-2-(3,4-di-allyloxyphenyl)ethyl 2,6-di-O-acetyl-3-O-(2,3,4-tri-O-acetyl--l-rhamnopyranosyl)-4-O-(3,4-di-allyloxycaffeoyl)--d-glucopyranoside 14 in 60% yield. Deprotected intermediates of compounds 2, 11, 14, and 19 which were obtained in high yield would be useful for biological and medicinal studies of phenylpropanoid glycosides.Part of this study was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April, 2002  相似文献   
6.
ABSTRACT:   Post-release movement and diel activity patterns of hatchery-reared and wild black-spot tuskfish were examined using ultrasonic telemetry. Five hatchery-reared and four wild fish were released in the sandy bottom of Urasoko Bay, Ishigaki Island, Okinawa, Japan, and monitored using automated monitoring receivers from November 2005 to February 2006. Both hatchery-reared and wild fish tended to stay near the release site for over two weeks, before leaving the release site. Both hatchery-reared and wild tuskfish showed diurnal rhythm intermittently; signals were recorded more frequently in the daytime and less frequently in the nighttime, suggesting that the fish of both origins were active during the day and inactive during the night. These findings indicate that the one-year-old hatchery-reared tuskfish have some consistent behavioral characteristics with those of the wild.  相似文献   
7.
The environmental history of the shirauo, Salangichthys microdon, was examined in terms of strontium (Sr) and calcium (Ca) uptake in the otolith, by means of wavelength dispersive X‐ray spectrometry on an electron microprobe. Anadromous and lacustrine type of the shirauo were found to occur sympatric. Otolith Sr concentration or Sr : Ca ratios of anadromous shirauo fluctuated strongly along the life‐history transect in accordance with the migration (habitat) pattern from sea to freshwater. In contrast, the Sr concentration or the Sr : Ca ratios of lacustrine shirauo remained at consistently low levels throughout the otolith. The higher ratios in anadromous shirauo, in the otolith region from the core to 90–230 μm, corresponded to the initial sea‐going period, probably reflecting the ambient salinity or the seawater–freshwater gradient in Sr concentration. The findings clearly indicated that otolith Sr : Ca ratios reflected individual life histories, enabling these anadromous shirauo to be distinguished from lacustrine shirauo.  相似文献   
8.
Mung bean trypsin inhibitor (MBTI) of the Bowman-Birk family was purified to homogeneity with a molecular mass of approximately 9 kDa on tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and 8887.25 Da as determined by matrix-assisted laser desorption/ionization-quadrupole ion trap-time-of-flight mass spectrometry (MALDI-QIT-TOF MS). Using blue scad myofibrillar proteins as targets, it was found that, in the absence of MBTI, proteolysis of myofibrillar proteins, especially myosin heavy chain (MHC), could be identified after incubation at 55 °C for 2 h, while in the presence of MBTI, with a final concentration of 25 ng/mL, proteolysis of these proteins was greatly suppressed even after incubation for 3 h. Although cysteine proteinase inhibitor E-64 was also effective in preventing protein degradation, inhibitors for metallo- and asparatic proteinases did not reveal obvious inhibitory effects. Our present results strongly suggested that the naturally occurring legume bean seed protein MBTI can be used as an effective additive in preventing marine fish blue scad surimi gel softening, which is quite possibly caused by myofibril-bound serine proteinase (MBSP).  相似文献   
9.
Column experiments were conducted using ideal natural sands and stainless-steel beads to examine the complete dissolution behavior of an organic immiscible liquid. Trichloroethene was used as the representative organic liquid. The elution curves exhibited multi-step behavior, with multiple extended periods of relatively constant contaminant flux. These secondary steady-state stages occurred at concentrations several orders-of-magnitude below aqueous solubility for the well-sorted sands. In contrast, the secondary steady-state stages occurred within 1 log of aqueous solubility for the poorly sorted sand. The non-ideal behavior is hypothesized to result from constraints to hydraulic accessibility of the organic liquid to flowing water, which may be expected to be mediated by the pore-scale configuration of the flow field and the fluid phases.  相似文献   
10.
McLaren and Crawford's method for fractionating soil Cu was modified, and used to fractionate soil Cd, Zn, Pb, and Cu in 38 soil samples from 11 soil profiles from industrially polluted and nearby unpolluted areas. Pollutant metals, especially Cd and Zn, were more soluble than the native soil metals. On average, approximately 45% of Cd was present in the CaCl2 soluble (CA) fraction, whereas corresponding values for the other metals were below 10%. The percentages of each metal in the CA fraction followed the order Cd > Zn > Pb > Cu. The same order was observed for the acetic acid soluble (AAC) fraction. Approximately 30% of total Pb and Cu were present in the pyrophosphate soluble (PYR) fraction, and only 10% of total Cd and Zn. Approximately 20% of total Zn or Pb and 10% of Cd or Cu were present in the free oxide (OX) fraction. Only 20% of Cd and between 40–50% of the other 3 metals were present in the residual (RES) fraction. The results show that Cd is more labile than the other 3 metals.  相似文献   
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