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511.
Mariko Nagatani Kayoko Kudo Seiki Yamakawa Toko Ohira Yuko Yamaguchi Shinichiro Ikezaki Isamu Suzuki Tsubasa Saito Toru Hoshiya Kazutoshi Tamura Kazuyuki Uchida 《Journal of toxicologic pathology》2013,26(3):263-273
In order to accurately assess the carcinogenicity of chemicals with regard to rare
tumors such as rat CNS tumors, sufficient information about spontaneous tumors are very
important. This paper presents the data on the type, incidence and detected age of CNS
tumors in F344/DuCrlCrlj (a total of 1363 males and 1363 females) and Crl:CD(SD) rats (a
total of 1650 males and 1705 females) collected from in-house background data-collection
studies and control groups of carcinogenicity studies at our laboratory, together with
those previously reported in F344 and SD rats. The present data on F344/DuCrlCrlj rats
(F344 rats) and Crl:CD(SD) rats (SD rats) clarified the following. (1) The incidences of
all CNS tumors observed in F344 rats were less than 1%. (2) The incidences of malignant
astrocytoma and granular cell tumor were higher in male SD rats than in female SD rats.
(3) The incidences of astrocytoma and granular cell tumor were higher in SD rats than in
F344 rats. (4) Among astrocytoma, oligodendroglioma and granular cell tumor,
oligodendroglioma was detected at the youngest age, followed by astrocytoma, and
ultimately, granular cell tumor developed in both strains. The incidences observed in our
study were almost consistent with those previously reported in F344 and SD rats. 相似文献
512.
Chie Kato Atsuhiko Kato Kenji Adachi Etsuko Fujii Kaori Isobe Tomochika Matsushita Takeshi Watanabe Masami Suzuki 《Journal of toxicologic pathology》2013,26(1):41-49
Some therapeutic antibodies as anticancer agents exert their effects through the host immune system, but the factors that predict their cytotoxicity, including complement-dependent cytotoxicity (CDC), are unclear. In the present study, we attempted to elucidate some of these factors in a preclinical model. CDC-related mesangiolysis caused by administration of the anti-Thy-1.1 antibody can be studied in the rat anti-Thy-1 glomerulonephritis model, so the model was used in this study. Three animals each were sacrificed at 0.5, 1, 8, 24 and 48 hours after i.v. administration of the anti-Thy-1.1 antibody at 1mg/kg. The distribution of the Thy-1.1 antigen and 2 membrane complement regulatory proteins (mCRPs), Crry and CD55, in three non-treated animals and the distribution of the injected antibody and C3 in the model was studied by immunohistochemistry. In the mesangial cells of the kidney, both expression of the antigen and distribution of the antibody with C3 deposition were observed with weak expression of mCRPs. There was also antigen and antibody distribution in the medullary cells of the adrenal gland and in the lymphocytes of the thymus but no C3 deposition, which was thought to be related to high expression of mCRPs. The antigen was observed in several other organs and tissues without distribution of the antibody. Cell death was only observed in the mesangial cells. These results clearly demonstrate that activation of CDC is regulated by several factors, such as distribution of the target molecule, antibody distribution and the balance among the molecules of the CDC cascade and mCRPs. 相似文献
513.
Kitaura R Kitagawa S Kubota Y Kobayashi TC Kindo K Mita Y Matsuo A Kobayashi M Chang HC Ozawa TC Suzuki M Sakata M Takata M 《Science (New York, N.Y.)》2002,298(5602):2358-2361
We report the direct observation of dioxygen molecules physisorbed in the nanochannels of a microporous copper coordination polymer by the MEM (maximum entropy method)/Rietveld method, using in situ high-resolution synchrotron x-ray powder diffraction measurements. The obtained MEM electron density revealed that van der Waals dimers of physisorbed O2 locate in the middle of nanochannels and form a one-dimensional ladder structure aligned to the host channel structure. The observed O-O stretching Raman band and magnetic susceptibilities are characteristic of the confined O2 molecules in one-dimensional nanochannels of CPL-1 (coordination polymer 1 with pillared layer structure). 相似文献
514.
Takeru Gonai Toru Manabe Eiichi Inoue Mikio Hayashi Toshiya Yamamoto Tateki Hayashi Fumio Sakuma Masakazu Kasumi 《Scientia Horticulturae》2006
Although there have been some attempts to obtain intergeneric hybrids between Japanese pear (Pyrus pyrifolia Nakai) and apple (Malus × domestica Borkh.) mature hybrids have not been generated due to hybrid lethality. Shoots from immature hybrid embryos were gamma irradiated and cultured at normal temperature conditions to obtain viable intergeneric plants. Gamma irradiation doses of 50 and 100 Gy cultured at 25 °C killed all shoots but there was one survivor at 150 Gy and 25 °C. Hybrid status of the shoot was confirmed by using morphology, flow cytometry and SSR markers. The intergeneric plant had similar leaf serrations to apple and similar petioles to Japanese pear. Flow cytometric analysis revealed that the intergeneric shoot had a DNA content intermediate between the parents. SSR analysis showed one allele from each parent for all 16 SSR loci investigated. These data strongly suggest that the obtained shoot is a true hybrid between Japanese pear and apple. 相似文献
515.
Yoshiki Takayama Minamo Hirahara Xin Liu Syuhei Ban Tatsuki Toda 《Aquaculture Research》2020,51(9):3741-3750
The understanding of the biological responses of copepods under crowding conditions contributes to establish their stable cultures at high densities for aquaculture industry, which are preferred live feeds for fish larvae. The present study investigated survivorship, fecundity, hatching success and respiration rate, of Acartia steueri raised under five densities, from 100 to 2,000 ind. L?1, to clarify the biological responses of the copepod under dense culture. There were no significant differences in survival, fecundity and hatching success among all density conditions, whereas the respiration rate at 2,000 ind. L?1 decreased by 80% as compared with a condition at 100 ind. L?1. The female copepods raised under a copepod density of >500 ind. L?1 probably invested a larger proportion of energy in reproduction in relation to total assimilated energy as compared with females under lower copepod densities. This change of energy allocation may allow A. steueri under high densities to maintain high fecundity. Acartia steueri might be a promising species for dense culture because its mortality and fecundity were independent of the effect of crowding, and the density‐dependent reduction in the metabolic rate might increase reproductive investment to maintain a constant rate of reproduction even under high densities. 相似文献
516.
Optimal period for the effective promotion of initial swim bladder inflation in yellowfin tuna,Thunnus albacares (Temminck and Schlegel), larvae 下载免费PDF全文
517.
Yoshio Kunimune Yasushi Mitsunaga Kazuyoshi Komeyama Masanari Matsuda Toru Kobayashi Tsutomu Takagi Takeshi Yamane 《Fisheries Science》2011,77(4):521-532
Seasonal habitat use by nigorobuna Carassius auratus grandoculis Temminck et Schlegel and gengoroubuna Carassius cuvieri (Temminck et Schlegel) in Lake Biwa was investigated using acoustic telemetry. Twenty-three nigorobuna and 11 gengoroubuna
specimens caught using set-nets in the lake’s south basin were surgically fitted with acoustic transmitters and then released.
Signals from the fishes were recorded by 23 receivers installed around the lake. Between April and June 2007, the first spawning
season after release, signals were received from all tagged fishes. Thereafter, until the second spawning season, signals
were collected from 26 and 45% of released nigorobuna and gengoroubuna individuals, respectively. Seasonal habitat preferences
for these species were studied by distance-based analysis. The analysis revealed that nigorobuna tended to stay near their
spawning area in the south basin of the lake throughout the year, whilst gengoroubuna tended to show a seasonal migration
pattern between the north and south basins. After the spawning season, the latter species migrated to the north basin where
it remained until the next spawning season, when it returned to the south basin. This is the first report of seasonal migration
of nigorobuna and gengoroubuna in Lake Biwa. 相似文献
518.
Trimethylamine-N-oxide (TMAO) degrades to dimethylamine (DMA) and formaldehyde, which cause a decline in fish quality. Suppression of DMA
formation in frozen surimi was investigated using croaker, lizardfish, and walleye pollock. The leaching process in surimi
processing was shown to reduce not only the TMAO, iron, and taurine content, but also to reduce unidentified factors that
accelerate DMA formation in lizardfish muscle; in contrast, unidentified factors that suppress DMA formation were reduced
in croaker and pollock muscle. Sucrose, used as a cryoprotectant, was shown to decrease DMA formation in vitro, likely due
to the reduction in freezing-induced concentration of solutes. The effects of pH on DMA formation were different in minced
frozen meat among the three species. DMA formation was not observed in croaker when the pH varied between 6 and 8. On the
other hand, DMA was elevated in lizardfish under acidic conditions, and DMA formation in pollock was maximal when the pH of
the meat was neutral. Thus, the suppression of TMAO degradation by surimi processing results from the removal of TMAO, iron,
and reductants from fish meat; sucrose also reduces DMA formation. Furthermore, unidentified factors in croaker, lizardfish,
and pollock meat substantially affect DMA formation. 相似文献
519.
Tetsuro Shiraishi Suvarna D. Ketkar Yoshiki Katoh Mitsuo Nyuji Akihiko Yamaguchi Michiya Matsuyama 《Fisheries Science》2009,75(3):649-655
Female Japanese chub mackerel Scomber japonicus of the Tsushima Current subpopulation were collected during the spawning season from March to May 2001. A total of 137 adult
females were caught between midnight and daybreak. A considerable number of fish displayed new postovulatory follicles (POF),
whereas there was no evidence of germinal vesicle breakdown or hydrated oocytes in any of the fish collected. This suggests
a daily spawning synchronicity toward midnight. To estimate the spawning frequency (S), the female reproductive state was classified into four criteria based on the degenerative stage of the POFs and the developmental
stage of the oocytes. To stage the POFs according to age and determine the stage duration, ovaries from S. japonicus were induced to spawn in the laboratory and were sampled 0–72 h after ovulation at appropriate intervals. The average S, which is evaluated from four different indices, was 16.9%, corresponding to the average female chub mackerel spawned every
5.9 days (8.5 times) during the 50 days. 相似文献