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31.
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
32.
AbstractWe observed carbon dioxide (CO2) flux at two experimental plots (wheat (Triticum aestivum L.) -planted and bare) for a year using an automatically controlled chamber. At each plot, two chambers were installed at six observation points by rotation. Consequently, the total installment duration at each point was one-third of the entire experimental period. Although we manually moved the chambers periodically, they hampered wheat growth and reduced the dried weight of harvested wheat by 65%. However, they did not influence the carbon (C) content ratio of harvested wheat. The rate of decrease of soil water contents after rainfall in the wheat plot was higher than that in the bare plot, especially after the canopy height reached around 30 cm. The maximum gap of soil water content at 5 cm depth between the two plots was about 5%. Wheat mitigated the increase of soil temperature in the daytime. The gap of soil temperature at 2 cm depth between the two plots sometimes exceeded 10°C. Considering the difference between dried weights of harvested wheat per unit ground area inside and outside the chamber collar, the annual net ecosystem exchange (NEE), whole ecosystem respiration and gross primary production were estimated respectively as –103 g C m?2 y?1, 831 g C m?2 y?1 and–934 g C m?2 y?1. The absolute values of each were smaller than those reported from past studies. Adding the exported carbon of harvested wheat (364 g C m?2) and subtracting the imported carbon of the seeds (3.1 g C m?2) to the NEE, net biome production across the ground surface was 259 g C m?2. It was greater than that in the bare plot (187 g C m?2). Although further improvements of measurements and more accurate estimated equations are necessary to evaluate the carbon budget correctly with chamber measurements, our chamber measurement captured the NEE variation, responding to seasonal, meteorological and biological changes. 相似文献
33.
Jun Murase Yoko Shinohara Kazunori Yokoe Risa Matsuda Susumu Asakawa Tomoyoshi Hashimoto 《Soil Science and Plant Nutrition》2013,59(6):927-933
Soil solarization is an ecologically friendly method of controlling various plant pathogens and pests, but also affects non-pathogenic members of the soil biota. Here, we studied the impact of soil solarization on the community structure of soil ciliates using a culture-independent molecular approach, namely denaturing gradient gel electrophoresis (DGGE) of targeted 18S rRNA gene fragments. Greenhouse soil with added organic fertilizers was solarized for 33 days at an average temperature of 47–48°C. Solarization caused a drastic change in the ciliate community. The variation between replicates was large, which suggested that the distribution of ciliates was spatially heterogeneous in the soil, probably due to their decreased numbers. In contrast, non-solarized soil had a stable and homogeneous ciliate community during the experimental period. In solarized soil, most of the original ciliate community recovered 76 days after solarization. Sequence analysis of DGGE fragments indicated that both r-selected and K-selected species of ciliates were affected by solarization but recovered with time after solarization. Our results demonstrated both the vulnerability and resilience of the ciliate community to soil solarization and also the utility of using molecular-based analysis of ciliate communities as bioindicators of soil stress caused by solarization. 相似文献
34.
The aim of the present study was to clarify the effect of photoperiod on nighttime secretion of growth hormone (GH) in goats. Adult female goats were kept at 20°C with an 8 h or 16 h dark photoperiod, and secretory patterns of GH for 8 h in the dark period were examined with the profile of prolactin (PRL) secretion. GH was secreted in a pulsatile manner in the dark period. There were no significant differences in pulse frequency between the 8‐ and 16‐h dark photoperiods; however, pulse amplitude tended to be greater in the group with the 16‐h dark photoperiod (P = 0.1), and mean GH concentrations were significantly greater in the same photoperiod (P < 0.05). PRL secretion increased quickly after lights off under both photoperiods. The PRL‐releasing responses were weaker in the 8‐h than 16‐h dark photoperiod. The secretory response to photoperiod was more obvious for PRL than GH. The present results show that a long dark photoperiod enhances the nighttime secretion of GH in female goats, although the response is not as obvious as that for PRL. 相似文献
35.
Yosuke Yanai Tomoyoshi Hirota Manabu Nemoto Nobuhisa Koga 《Soil biology & biochemistry》2011,43(9):1779-1786
It has been suggested that soil-thawing and snow-melting are critical triggers for vigorous emissions of nitrous oxide (N2O) from soils in cold regions. However, because soil freezing is affected by air temperature and snow cover, accurate predictions that estimate subsequent emissions of this important greenhouse gas are difficult to make. In this study, we measured in situ soil gas N2O and oxygen (O2) concentrations at two experimental sites in northern Japan over the period of a year, from November 2008 to October 2009, to clarify the factors stimulating N2O production in soil at low temperatures. The sites were N-fertilized bare arable lands with different soil frost depths and snowmelt rates, according to the snow cover management imposed. Winter-to-spring net N2O fluxes, ranging from −0.10 to 1.95 kg N2O-N ha−1, were positively correlated with the annual maximum soil frost depth (ranging from 0.03 to 0.41 m; r = 0.951***). In the plots with deeper maximum soil frost, winter-to-spring N2O fluxes represented 58% to 85% of the annual values. Soil N2O production was stimulated when the soil frost depth was greater than 0.15 m or the daily mean soil temperature at 0.05-m depth was below −2.0 °C. In the soil with the greatest frost depth, soil gas N2O concentrations at the depth of 0.10 m peaked at 46 ppm when soil gas O2 concentrations fell down to 0.12 m3 m−3 under soil temperature below 0.0 °C. Snowmelt acceleration had no stimulating effect on N2O production in the soil during the winter-to-spring period. 相似文献
36.
Hayato SAITO Tatsuru SAWADA Tomoyoshi YAEGASHI Yuki GOTO Jin JIN Ken SAWAI Tsutomu HASHIZUME 《Animal Science Journal》2012,83(6):487-492
The aims of the present study were to clarify the effect of kisspeptin‐10 (Kp10) on the secretion of luteinizing hormone (LH) and testosterone (T) in pre‐pubertal and post‐pubertal male ruminants. Four male goats (Shiba goats) were given an intravenous (i.v.) injection of Kp10 (5 µg/kg body weight (b.w.)), gonadotoropin‐releasing hormone (GnRH, 1 µg/kg b.w.), or 2 mL of saline as a control at the ages of 3 (pre‐pubertal) and 6 (post‐pubertal) months. A single i.v. injection of Kp10 significantly stimulated the release of LH and T in both groups. The area under the response curve (AUC) of LH for a 60‐min period after the i.v. injection of Kp10 was significantly greater in the pre‐pubertal goats (P < 0.05). The AUC of T for a 120 min period post‐injection did not differ between the two age groups. A single i.v. injection of GnRH also significantly stimulated the release of LH and T in both groups (P < 0.05). The secretory pattern of LH and T in response to GnRH resembled that in response to Kp10. These results show that the LH‐releasing response to Kp10 is greater in pre‐pubertal than post‐pubertal male goats. They also show that Kp10, as well as GnRH, is able to stimulate the release of T in male goats. 相似文献
37.
Komiya T Sadamasu K Kang MI Tsuboshima S Fukushi H Hirai K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(9):1047-1048
The seroprevalence of Coxiella burnetii infection among pet cats in Japan and Korea and stray cats in Japan was investigated by an indirect fluorescent antibody technique and PCR test. Forty-four (14.2%) of 310 pet cats in Japan were seropositive, as were 15 (41.7%) of 36 stray cats in Japan and 10 (8.6%) of 116 pet cats in Korea. The antibody positive rate in stray cats was significantly higher than that in pet cats, but there was no correlation between the rates in Japanese and Korean pet cats. In this study, the prevalence of C. burnetii infection among cats in different living environments was found and it is difficult to deny that stray cats would be one of the important sources of infection for human Q fever. 相似文献
38.
Hajime Goto Noriyuki Asanome Keitaro Suzuki Tomoyoshi Sano Hiroshi Saito Yohei Abe Masaru Chuba Takeshi Nishio 《Breeding Science》2014,63(5):489-494
The whiteness of cooked rice and rice cakes was evaluated using a portable spectrophotometer with a whiteness index (WI). Also, by using boiled rice for measurement of Mido values by Mido Meter, it was possible to infer the whiteness of cooked rice without rice cooking. In the analysis of varietal differences of cooked rice, ‘Tsuyahime’, ‘Koshihikari’ and ‘Koshinokaori’ showed high whiteness, while ‘Satonoyuki’ had inferior whiteness. The whiteness of rice cakes made from ‘Koyukimochi’ and ‘Dewanomochi’ was higher than the whiteness of those made from ‘Himenomochi’ and ‘Koganemochi’. While there was a significant correlation (r = 0.84) between WI values and whiteness scores of cooked rice by the sensory test, no correlation was detected between the whiteness scores and Mido values, indicating that the values obtained by a spectrophotometer differ from those obtained by a Mido Meter. Thus, a spectrophotometer may be a novel device for measurement of rice eating quality. 相似文献
39.
T. Hashizume T. Sawada T. Yaegashi H. Saito A. Ezzat Ahmed Y. Goto Y. Nakajima J. Jin E. Kasuya G.M. Nagy 《Domestic animal endocrinology》2010
The aims of the present study were to clarify the effect of salsolinol (SAL), a dopamine (DA)-derived endogenous compound, on the secretion of prolactin (PRL) in cattle. The experiments were performed from April to June using calves and cows. A single intravenous (i.v.) injection of SAL (5 mg/kg body weight [BW]) or sulpiride (a DA receptor antagonist, 0.1 mg/kg BW) significantly stimulated the release of PRL in male and female calves (P < 0.05), though the response to SAL was smaller than that to sulpiride. The secretory pattern of PRL in response to SAL or sulpiride in female calves resembled that in male calves. A single i.v. injection of SAL or sulpiride significantly stimulated the release of PRL in cows (P < 0.05). There was no significant difference in the PRL-releasing response between the SAL- and sulpiride-injected groups in cows. A single intracerebroventricular injection of SAL (10 mg/head) also significantly stimulated the release of PRL in castrated calves (P < 0.05). These results show that SAL is involved in the regulatory process for the secretion of PRL, not only in male and female calves, but also in cows. The results also suggest that the potency of the PRL-releasing response to SAL differs with the physiological status of cattle. 相似文献
40.