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141.
Oyamada T Tanaka H Park CH Ueki H Komiya T Arai S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(11):1155-1161
Of 197 cases of canine oral malignant melanoma, 29 cases with myxoid, cartilage, and osteoid formation were studied pathologically and immunohistochemically. Tumor tissues were classified into spindle cell type (13 cases), epithelioid cell type (1 case), and mixed type (15 cases). Myxoid matrixes (29 tumors) were formed mainly in the tissues of spindle cell type and were positive for Alcian blue (pH 2.5). Cartilaginous matrixes (12 tumors) were formed in the myxoid tumor tissues. The morphology of atrophied neoplastic cells, which were embedded in the cartilage cavities, significantly differed from that of spindle cells proliferating in surroundings. There were reticular areas in the process of transitioning from myxoid to cartilaginous matrixes. Osteoid matrixes were not continuous with myxoid or cartilaginous matrixes, and arose as eosinophilic trabeculae in the dense collagenous connective tissues. A calcified bone trabecula was present among the osteoid trabeculae in a case. Melanin-producing melanocytes were proliferating in the collagenous matrixes, while amelanotic cells were in the osteoid matrixes. Immunohistochemistry demonstrated proliferating neoplastic cells as melanocytes. All cells in/out of these three matrixes were positive for Melan-A, S-100 protein, NSE, and vimentin. From these results, it is suggested that cartilage and osteoid matrixes are produced by dedifferentiated melanocytes. 相似文献
142.
Yuuki Kawabata Kimio Asami Masato Kobayashi Taku Sato Koichi Okuzawa Hideaki Yamada Kenzo Yoseda Nobuaki Arai 《Fisheries Science》2011,77(3):345-355
In this study, the effect of shelter acclimation on the post-release movement and putative predation mortality of hatchery-reared
black-spot tuskfish Choerodon schoenleinii was examined using acoustic telemetry. We acclimated four 1-year-old fish to shelters in cages before release and compared
their movements with six nonacclimated fish. Since it was not possible to compare the behavioral pattern between the former
and the latter fish due to the short periods the latter fish were available to be monitored, we also compared their movements
with those of large nonacclimated fish that were less likely to be preyed upon. Sixty-seven percent of the nonacclimated fish
showed atypical movements before the signals ceased to be detected, a pattern that suggested a predation event had occurred,
whereas none of the acclimated and large nonacclimated fish showed the atypical movements. In addition, the probability of
detection cessation was about 13 times lower in the acclimated than nonacclimated fish. The signal detection patterns suggest
that the acclimated fish utilized night-time shelters from the first night after release, while the large nonacclimated fish
started to utilize shelters several days after release. Therefore, it is likely that the shelter acclimation enhanced the
shelter utilization by tuskfish, possibly decreasing post-release predation mortality. 相似文献
143.
The brain nanopeptide arginine vasotocin (AVT) and its mammalian homolog arginine vasopressin are involved in the regulation
of social and reproductive behavior. We investigated the relationship between social rank formation and the brain AVT system
in the false clown anemonefish (Amphiprion ocellaris), which forms a social rank that leads to sex differentiation in higher-ranked individuals. Tanks of three sexually immature
fish were kept for 90 days and each fish’s behavior was observed once a month. The social rank of each individual was distinguishable
by behavior, but gonadosomatic index (GSI) did not differ significantly. The number of AVT neurons in the magnocellular layer
in the preoptic area (POA) increased in subordinate individuals and declined with increasing hierarchical dominance. These
results suggest that social rank formation modulates AVT production in the brain of the clown anemonefish and may influence
their later sex differentiation. 相似文献
144.
Machiko Kirikae Ryusuke Hatano Hideaki Shibata Yumiko Tanaka 《Water, air, and soil pollution》2001,130(1-4):697-702
We determined proton budgets of surface soils in a deciduous forest (Df) and a coniferous forest (Cf) of Volcanogenous Regosols in Tomakomai, Hokkaido of northern Japan. The total H+ source was 12.9 and 11.6 kmolc ha?1 y?1 at Df and Cf respectively, and the external H+ was 1% at Df and 2% at Cf. The primary H+ sources were vegetation uptake of base cations and nitrification, while the major H+ sinks were release of base cations and NO3 + uptake by vegetation. Leaching incubation experiments using A horizon soils including Df and Cf with NH4 + solutions (5.3, 15.9 mg N L?1) showed that H+ from nitrification was generally higher in the Df soil than Cf soil, and nitrification of Tomakomai Df soil was the highest in both treatments. Results of multiple regression analyses suggested that pHkCl and exchangeable Ca2+ contributed to the H+ generation via nitrification. Leaching experiments with dilute HCl (pH 3.3) revealed that cation release (mainly Ca2+) occurred, and the proportion of release by decrease of exchangeable cations was higher than that by mineral weathering. Mineral weathering in the Tomakomai soil was higher than the other soils. 相似文献
145.
Yuichi?YamaokaEmail author Hayato?Masuya Nobuaki?Ohtaka Hideaki?Goto Shigeru?Kaneko Yoshio?Kuroda 《Journal of Forest Research》2004,9(1):67-74
Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied. 相似文献
146.
玉米自交系对低钾胁迫耐性的差异 总被引:27,自引:1,他引:26
采用耐低钾的玉米自交系T和一般的自交系C,以4水平钾浓度的水培方法进行对照研究。结果表明,在高钾情况下,两自交系干重几乎相同,随着钾浓度的下降,自交系T的干重明显大于自交系C:;随钾浓度的下降,自交系C缺钾症状加重,而自交系T除一K处理外均无缺钾症状;缺乏钾素。自交系C的主根伸长增加及冠/根比下降程度比自交系T明 相似文献
147.
ABSTRACT: In this study, the site of spawning ground and the relationship between oceanographic conditions and gonadal development and emaciation of the Japanese common squid Todarodes pacificus were examined based on data from research cruises. The research cruises were conducted in the south-western part of the Sea of Japan and the East China Sea in the winter of 1999. Sea surface temperature (SST) ranged 12.7–23.2°C in the survey area. Mature females concentrated on the continental shelf of the East China Sea, suggesting a major spawning ground was formed in this area. Gonadal development of the collected squid was examined using ovary somatic index (OSI) and oviduct somatic index (ODSI) in females, and emaciation was examined using mantle muscle somatic index (MI) and hepatosomatic index (HSI). Mean OSI and ODSI increased with SST at the stations where SST was greater than 15°C, particularly where SST ranged between 15 and 18°C. In contrast, mean MI and HSI decreased with increase in SST at the stations where SST was above 15°C. These results indicate that female gonads develop rapidly at SST above 15°C, and at the same time adult squids tend to be emaciated at this temperature condition. 相似文献
148.
ABSTRACT: Acoustic survey and a geographic information system (GIS) were used conjointly to estimate the significance of bottom substrate to explain fish abundance distribution in the complex topography context of a marine hill. The survey was conducted in the Hachirigase hill, off south-western Honshu Island in the Sea of Japan. Analysis of acoustic data focused on a 10-m thick layer beginning at the bottom, assuming that bottom influence does not exceed this distance. Area backscattering strength ( S a ) values were rescaled in order to reflect real differences before being analyzed. Results show that the influence of the different parameters taken into account (bottom depth, bottom substrate and water temperature) varies widely from one place to another. Bottom substrate is above all important in the zone located to the west of the peak. The kriging and stratification methods were applied to the S a distribution for estimating the total S a in the hill. Differences between results are discussed. Conjoint use of acoustic survey and GIS is an effective method for analyzing and estimating fish abundance distribution in a marine hill. 相似文献
149.
Spatiotemporal changes in growth patterns of chum salmon Oncorhynchus keta that returned to the Ishikari (Japan) and Namdae (Korea) rivers in 1984–1998 were investigated using scale analysis. Juvenile
chum salmon from both populations left coastal marine areas after spring at a size of over 8 cm fork length (FL). In summer,
juvenile salmon from the Namdae River entered the Okhotsk Sea at a larger FL than did Ishikari River juveniles. There were
no significant differences in annual growth between populations of 1-, 2-, and 4-year-old fish. For 3-year-old fish, however,
Namdae River salmon had significantly higher synchronous and sympatric growth than did Ishikari River salmon. Mean FL of adults
was also larger in Namdae River salmon than in Ishikari River salmon. Analysis of covariance (ANCOVA) results showed (1) negative
linear relations between FL and catch, (2) homogeneous slopes of those relations at regional and species levels, and (3) nonhomogeneous
slopes at the population level, indicating that density-dependent effects on growth were most significant at this level. We
concluded that growth of chum salmon was concurrently influenced by stronger effects of intrapopulation competition and weaker
effects of inter- and intraspecific interactions in the Bering Sea. 相似文献
150.
Haiyun Wu Hitoshi Ohnuki Kyoko Hibi Huifeng Ren Hideaki Endo 《Fish physiology and biochemistry》2016,42(1):19-27
Fishes display a wide variation in their physiological responses to stress, which is clearly evident in the plasma corticosteroid changes, chiefly cortisol levels in fish. In the present study, we describe a novel label-free immunosensor for detecting plasma cortisol levels. The method is based on immunologic reactions and amperometric measurement using cyclic voltammetry. For the immobilization of the antibody on the surface of sensing electrode, we used a self-assembled monolayer of thiol-containing compounds. Using this electrode, we detect the CV signal change caused by the generation of antigen–antibody complex. The immunosensor showed a response to cortisol levels, and the anodic peak value linearly decreased with a correlation coefficient of 0.990 in diluted plasma. The specificity of the label-free immunosensor system was investigated using other steroid hormones, such as 17α, 20β-dihydroxy-4-pregnen-3-one, progesterone, estriol, estradiol, and testosterone. The specific detection of cortisol was suggested by a minimal change from ?0.32 to 0.51 μA in the anodic peak value of the other steroid hormones. The sensor system was used to determine the plasma cortisol levels in Nile tilapia (Oreochromis niloticus), and the results were compared with those of the same samples determined using the conventional method (ELISA). A good correlation was obtained between values determined using both methods (correlation coefficient 0.993). These findings suggest that the proposed label-free immunosensor could be useful for rapid and convenient analysis of cortisol levels in fish plasma samples. 相似文献