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排序方式: 共有832条查询结果,搜索用时 15 毫秒
121.
Katsuhiko Yoshizawa Yuichi Kinoshita Yuko Emoto Ayako Kimura Norihisa Uehara Takashi Yuri Nobuaki Shikata Airo Tsubura 《Journal of toxicologic pathology》2013,26(2):141-148
N-Methyl-N-nitrosourea (MNU)-induced renal tumors in rats and Wilms tumors in humans were compared. Renal mesenchymal tumors (RMTs) and nephroblastomas (blastemal and epithelial components) in female Lewis rats treated with a single intraperitoneal injection of 50 mg/kg MNU at birth and Wilms tumors (blastemal, epithelial and mesenchymal components) in humans were analyzed for the expression of pancytokeratin (CK), vimentin, p63, α-smooth muscle actin (SMA), desmin, S-100, CD57, CD117/c-kit, Wilms tumor 1 protein (WT1) and β-catenin. The mesenchymal components of rat RMTs and human Wilms tumors expressed vimentin, SMA and β-catenin. The blastemal components of rat nephroblastomas and human Wilms tumors expressed vimentin, CD117/c-kit and β-catenin. The epithelial components of rat nephroblastomas and human Wilms tumors expressed vimentin and β-catenin. WT1 was expressed in different cellular components of rat tumors as compared with human Wilms tumors; the expression was seen in mesenchymal tumors and blastemal components of nephroblastomas in rats and epithelial components in human Wilms tumors. CK, p63 and CD57 were not expressed in rat RMTs or nephroblastomas, while CK and WT1 were expressed in epithelial components and CD57 was expressed in blastemal and epithelial components of human Wilms tumors. Rat and human tumors were universally negative for the expression of desmin and S-100. The immunohistochemical characteristics of rat renal tumors and human Wilms tumors may provide valuable information on the differences in renal oncogenesis and biology between the two species. 相似文献
122.
123.
K Kaneko E Uematsu Y Takahashi B Tong S Takino Y Wajiki T Kimura H Yamashiro Y Kaneko H Iwaisaki T Sugiyama T Yamada S Yamagishi 《Reproduction in domestic animals》2013,48(6):1001-1005
This study aimed to develop a polymerase chain reaction (PCR)‐based sexing and effective semen collection methods for black‐headed and straw‐necked ibis species. However, most birds are not sexually dimorphic, that is, the sexes appear similar. Therefore, the gender should be determined before semen collection. DNA was extracted from the blood samples of 11 black‐headed and 4 straw‐necked ibis. The sex was determined after PCR amplification of the EE0.6 region of W‐chromosome. The PCR products were separated using gel electrophoresis. A single band indicated the presence of the EE0.6 region and that the individual was a female, while no band indicated that the individual was a male. Further, the single bands from seven specimens were amplified. Semen collection was performed by massage or a combination of massage with electro‐ejaculation and was attempted during all four seasons. The semen was successfully collected in March from male straw‐necked ibis using the massage method. Limited motility, viability and concentration of straw‐necked ibis sperm were observed. The sperm length was 180 μm and that of the nucleus was 30 μm with acrosome located at the tip of the nucleus. Thus, the PCR‐based sexing proved to be an accurate molecular sexing method for black‐headed and straw‐necked ibis. Furthermore, we successfully collected semen and observed the stained sperm nucleus and acrosome of the straw‐necked ibis sperm. We propose that the use of this PCR methodology can be applied as a routine method for sex determination and semen collection in ibis species for future ecological research. However, considering our limited success, further studies on semen collection method are required. 相似文献
124.
Mark K. Asplen Gianfranco Anfora Antonio Biondi Deuk-Soo Choi Dong Chu Kent M. Daane Patricia Gibert Andrew P. Gutierrez Kim A. Hoelmer William D. Hutchison Rufus Isaacs Zhi-Lin Jiang Zsolt Kárpáti Masahito T. Kimura Marta Pascual Christopher R. Philips Christophe Plantamp Luigi Ponti Gábor Vétek Heidrun Vogt Vaughn M. Walton Yi Yu Lucia Zappalà Nicolas Desneux 《Journal of pest science》2015,88(3):469-494
125.
Masashi?Hatamoto Takanori?Tanahashi Jun?Murase Kazuo?Matsuya Motoki?Hayashi Makoto?Kimura Susumu?AsakawaEmail author 《Biology and Fertility of Soils》2008,44(3):527-532
To estimate the succession and phylogenetic composition of the eukaryotic communities responsible for the decomposition of
rice straw compost under flooded conditions during the cultivation period of paddy rice, denaturing gradient gel electrophoresis
(DGGE) analysis targeting 18S rDNA followed by sequencing was conducted in a Japanese paddy field. The eukaryotic communities
in rice straw compost incorporated into the flooded paddy field were influenced by the mid-season drainage and mainly composed
of fungi (Ascomycota, Zygomycota, and Chytridiomycota) and protozoa (Ciliophora, Euglyphida, and Dactylopodida), most of which
existed continuously during the cultivation period of paddy rice. The results indicated that these eukaryotic members were
associated with the decomposition of rice straw compost in paddy field soil directly or indirectly. 相似文献
126.
Relationships between body size and secondary sexual characters,and sperm characters in male Dolly Varden char (Salvelinus malma)
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Toshiaki Yamamoto Noritaka Hirohashi Eiji Fujiwara Tatsuya Suzuki Hatsuna Maruta Hirotake Omiya Shigeru Kitanishi 《Ecology of Freshwater Fish》2017,26(3):397-402
In Salmonidae, subordinate males are exposed to higher risks of sperm competition than dominant males and thus are expected to improve the sperm characteristics (sperm concentrations, sperm velocity and sperm longevity). In this study, we investigated the relationships between body size and secondary sexual characters (breeding colour, hump height and snout length), and sperm characteristics of one‐year‐old (newly matured) Dolly Varden char. Small males displayed higher sperm concentrations than large males. Moreover, males with dull breeding colours, but not with lesser snout length and hump height, displayed an increased sperm velocity compared to males with bright colours, suggesting a trade‐off between sperm quantity and the investment in breeding colour. In addition, sperm longevity decreased as sperm swimming velocity increased. These findings indicate that small males with dull breeding colours improve the quantity and quality of their sperm to a great extent to enhance their chances of reproductive success. 相似文献
127.
Hypocretin/orexin is produced exclusively in the dorsal and lateral hypothalamus but its projection is widespread within the brain and plays important roles. In this paper, we review the independent discoveries of the hypocretin/orexin peptides, the neuroanatomy of this system, and the link to the sleep disorder narcolepsy that has led to the idea that this system plays a crucial role in the regulation of sleep and wakefulness. 相似文献
128.
Sugiura K Akazawa T Fujimoto M Wijewardana V Mito K Hatoya S Taketani S Komori M Inoue N Inaba T 《Veterinary immunology and immunopathology》2008,126(3-4):388-391
To construct a vector for caspase-1 independent expression of canine IL-18, the signal sequence of canine IL-12p40 was fused to the sequence of mature IL-18 on the NdeI restriction site which is located at the 3' end of the signal sequence. The resulting vector expressed coding protein from transfected mammalian cells. The expressed protein was shown to have IL-18 bioactivity in a INF-gamma-inducing assay. These results suggest that the expression vector is the desired tool for advancement of dendritic cell (DC)-based cancer therapy, provided that the vector can successfully be transfected into dendritic cells. We propose a simple and widely applicable method for providing the signal sequence. 相似文献
129.
Yuka Maeda Keiko Nishimura Kazuhiro Kurosu Hitoshi Mizuguchi Shigeru Sato Fuminori Terada Shiro Kushibiki 《Animal Science Journal》2019,90(4):523-532
This study aimed to examine the effects of feeding kraft pulp (KP) on the growth performance, feed digestibility, and rumen fermentation of Japanese Black fattening steers. Ten Japanese Black fattening steers (aged 26 months) were randomly divided into control and KP groups. The control group (n = 5) was fed concentrate feed without KP, and the KP group (n = 5) was fed concentrate feed containing 10% KP. Both the groups were provided rice straw as roughage. The experiment was conducted over a period of 12 weeks. There was no significant difference in dry matter intake, daily body weight gain, and nutrient digestibility between both groups. No difference was observed in the ruminal concentrations of volatile fatty acids among the groups. At weeks 8 and 12 after the onset of the experiment, the acetate‐to‐propionate ratio in the ruminal fluid of the KP group was significantly higher than that of the control group. The average daily pH of ruminal fluid and activity of ruminal lipopolysaccharide did not differ between the groups. Our results suggested that the growth performance and feed digestibility in the Japanese Black fattening steers were not influenced by replacing concentrate feed with KP. 相似文献
130.
Shigeru NINOMIYA Masato AOYAMA Yumiko UJIIE Ryo KUSUNOSE Atsutoshi KUWANO 《Journal of Equine Science》2008,19(3):53-56
The objective of this study was to investigate the effect of straw, sawdust, coconut husk
(husk), and coconut fiber (fiber) on the welfare of stable horses by observing their
resting behavior. Twenty horses with ages ranging from 3 to 21 years were used at the
Equine Research Institute of the Japan Racing Association, Utsunomiya, Japan. Five horses
were allocated to each bedding condition. The behavior of each horse was recorded by video
camera for 3 days and was continuously sampled from 17:00 to 05:00. The total duration,
the number of bouts, and the mean and the maximum duration of bouts in standing rest,
sternal lying, and lateral lying were calculated and analysed by the Kruskal-Wallis test
and post hoc Steel-Dwass test. There was no difference in the standing rest and the
sternal lying among beddings. Significant differences were observed in these values in the
lateral lying among the different beddings (P<0.05). The values of the means of the
total duration, the number of bouts, and the mean and the maximum duration of bout in the
lateral lying were greater when husk was used as the bedding material than when sawdust
were used (P<0.05). The results of the observations show that the new bedding materials
would be as usable as straw. However, lateral lying was observed less frequently when
sawdust were used as bedding; this indicates that use of sawdust as bedding material will
decrease the welfare of stabled horses. 相似文献