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排序方式: 共有1436条查询结果,搜索用时 15 毫秒
1.
Nakagawa Koki Murase Jun Asakawa Susumu Watanabe Takeshi 《Journal of Soils and Sediments》2020,20(11):4034-4041
Journal of Soils and Sediments - To reveal whether microaerophilic Fe(II)-oxidizing bacteria (FeOB) participate in the Fe(II) oxidation at the oxic-anoxic interface in flooded paddy field soil,... 相似文献
2.
Saitoh Kanae Yoshimura Tomohiro Sun Luchuanyang Yang Min Wang Yao Taniyama Shigeto Hara Kenji Murayama Fumihito Nikawa Takeshi Tachibana Katsuyasu Hirasaka Katsuya 《Fisheries Science》2020,86(1):187-196
Fisheries Science - Fish oil containing omega-3 polyunsaturated fatty acids (PUFA) attenuates chronic inflammation found in obesity, leading to a reduction in insulin resistance. The effect of fish... 相似文献
3.
Taisei Nagata Mamoru Sameshima Taku Uchikawa Natsumi Osafune Takeshi Kitano 《Fisheries Science》2017,83(2):273-281
Episodes of summer mortality of the Kumamoto oyster Crassostrea sikamea are a major problem for its cultivation. Expression of the heat shock protein 70 (HSP70) is induced by various environmental stresses, including heat. We cloned and sequenced hsp70 complementary DNA from C. sikamea to investigate the relationship between hsp70 expression and heat tolerance in this oyster. Quantitative real-time polymerase chain reaction was performed using gill tissue dissected from oysters before and after heat shock for 1 h. The results showed hsp70 expression was faster and greater in oysters cultured at 20–22 °C than at 10–12 °C, and survival was lower among oysters cultured at 20–22 °C than at 10–12 °C. Moreover, heat tolerance was investigated by a 1-h pre-heat treatment, followed by exposure to heat shock conditions 5 days later. Survival was higher and hsp70 expression was notably lower in oysters that received the pre-heat treatment compared with those that did not. We conclude that a pre-heat treatment of only 1 h may be useful for inducing heat tolerance in C. sikamea, and that a low level of hsp70 expression after heat shock is an important index in selecting for high heat tolerance in these oysters. 相似文献
4.
Fumitaka Kondo Takashi Ohta Toshiharu Iwai Atsushi Ido Chiemi Miura Takeshi Miura 《Fish physiology and biochemistry》2017,43(6):1543-1555
The improvement in feed efficiency is one of the most important subjects in fish culture. The development of feed, in terms of good intake, high growth performance, and high feed efficiency is needed. Squid viscera are one of the candidates for alternative material in improving feed efficiency in fish culture. In the present study, we described the dietary effect of the squid viscera hydrolysate (SVH) on the growth performance of the red sea bream. The addition of SVH to feed caused significant increases in feed intake, fork length, and body weight and produced a marked improvement in feed conversion after 4 weeks of feeding. Furthermore, the results of this feeding revealed that low dietary levels of SVH promote growth performance in the red sea bream. We physiologically analyzed digestion and appetite in fish fed diet containing SVH. SVH promoted the activity of hepatic trypsin and lipase, gene expression of stomach pepsin, hepatic lipase, and pyloric caeca trypsin, thereby improving the nutrient availability in red sea bream. Moreover, the mRNA expression of appetite regulating factor, such as brain NPY and stomach ghrelin was significantly improved by dietary SVH. Our current results indicate that dietary SVH as alternative material produced excellent effects on growth performance, which is dependent on the promoting effect on digestion and appetite in red sea bream. 相似文献
5.
Noriyuki Koizumi Atsushi Mori Takuya Mineta Eiji Sawada Keiji Watabe Takeshi Takemura 《Paddy and Water Environment》2017,15(4):723-730
Fecal DNA samples from the red-eared slider and Reeves’ pond turtle, suspected pests of lotus root paddies, were used to identify the plant species eaten by these turtles in order to develop a strategy for rural ecosystem conservation. The fecal samples were obtained from young and adult individuals (mostly female) of both species living in agricultural canals surrounding lotus root paddies in Tokushima Prefecture, Japan. The samples were screened for the presence or absence of DNA from nine plant species using PCR and plant species-specific primers for the rbcL gene of chloroplast DNA. In the red-eared slider, our analysis identified seven plant species in the fecal DNA samples of adults and three plant species in those of young individuals. In Reeves’ pond turtle, our analysis identified two plant species from adult fecal samples and one species from those of young individuals. Thus, adult red-eared sliders consume a greater range of plants than young red-eared sliders or Reeves’ pond turtles. Both turtle species, independently of age, consumed lotus plants and were likely to cause feeding damage to lotus roots. Considering the plant species detected in adult red-eared sliders and these plant habitats, we suggest that this adult turtle is likely to travel between the agricultural canals and the lotus root paddies. These findings will help the development of strategies for preventing damage to lotus roots by these turtles; furthermore, they indicate that fecal DNA analysis will be applicable to investigation of the feeding habits of other animal species. 相似文献
6.
Keita W. Suzuki Taiki Fuji Akihide Kasai Sachihiko Itoh Shingo Kimura Yoh Yamashita 《Fisheries Oceanography》2020,29(1):66-83
Northwesterly cold winds characteristic of the East Asian Winter Monsoon (EAWM) dictate winter climatic conditions over the Japanese Archipelago. Japanese temperate bass Lateolabrax japonicus is a commercially important coastal fish that spawns offshore in winter and uses shallow waters as nursery habitats. To investigate the effects of EAWM on the planktonic period of L. japonicus, eggs, larvae, and juveniles were quantitatively collected in Tango Bay on the Sea of Japan side in winter and spring from 2007 to 2017. Although eggs occurred close to the mouth of the bay, planktonic larvae occurred further inside as they developed. The horizontal distribution of planktonic larvae, combined with water velocity data obtained from mooring observations, indicated that planktonic larvae are transported south‐ to westward through Ekman current and an anticyclonic circulation, which are driven by northwesterly winds. To evaluate survival during the planktonic period in each year class, the abundance of benthic larvae/juveniles was divided by winter total landings of Lateolabrax spp. (proxy of the spawning stock size). This survival index exhibited a positive correlation with the northwesterly component of winter winds, and a negative correlation with winter air temperature (average from December to February, Spearman's correlation, p < .05). There was, however, no significant correlation with winter water temperature or winter freshwater discharge in the bay. We conclude that northwesterly cold winds of EAWM play a critical role in transporting L. japonicus eggs and larvae toward nursery habitats, specifically beaches and estuaries fringing the innermost part of Tango Bay. 相似文献
7.
Bhuminad DEVKOTA Masahiro TAKAHASHI Saori SATO Kouya SASAKI Atsushi UEKI Takeshi OSAWA Masahiro TAKAHASHI Norio YAMAGISHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):875-878
Blood samples were obtained sequentially from 10 dairy cows around the time of
parturition to assess plasma fluctuations in estradiol-17β (E2) levels in
association with those of several bone resorption markers. Plasma E2
concentration increased sharply a few days prepartum and decreased quickly after
parturition. In terms of bone resorption markers, the plasma level of tartrate-resistant
acid phosphatase isoform 5b (TRAP5b) rose significantly, commencing 1 week prepartum, and
was maintained at this level to a few days postpartum. The plasma concentration of
carboxyterminal collagen cross-links of type-I collagen (CTx) increased significantly
after parturition. These observations suggest that osteoclast-mediated bone resorption was
activated after parturition when plasma E2 concentrations decreased. 相似文献
8.
Takeshi OHTA Shuichi KIMURA Masaya HIRATA Takahisa YAMADA Toshie SUGIYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1327-1330
The Spontaneously Diabetic Torii (SDT) fatty rat, a model for obese type 2 diabetes,
shows bone quantitative abnormalities, namely low bone mineral density (BMD). The
objective of this study was to evaluate bone morphological changes, in particular
identifying the bone qualitative abnormalities, in the SDT fatty rat. Male SDT fatty rats
showed increases in total trabecular area and trabecular number and decreases in
trabecular thickness in cancellous bones of the proximal tibia, indicating trabecular
miniaturization. The SDT fatty rat is useful for investigation of pathophysiological
changes in bone quality in diabetic osteoporosis. 相似文献
9.
Masato HIYAMA Ken Takeshi KUSAKABE Ai TAKESHITA Sinji SUGI Nobue KUNIYOSHI Hiroyuki IMAI Kiyoshi KANO Yasuo KISO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):305-311
LC3 − the mammalian homolog of Atg8 − was found as autophagosome membrane binding protein
in mammals and widely used as an autophagosomal marker. LC3A, B and C show different
expression patterns in each tissue. The aim of this study was to reveal the differences of
expression patterns among LC3 families in mouse placenta under normal condition and
nutrient starving condition. LC3A and B were highly expressed in decidual cells. LC3A and
B were increased in D14 compared with D12 and D16 in mouse placenta, while LC3C was
decreased. Starvation induced increase in LC3B expression specifically.
Immunohistochemistry showed different expression patterns among LC3A, B and C. LC3A
expression in syncytiotrophoblast was vanished by starvation. The results of real time
RT-PCR suggested differences between D12 and D16 in autophagic cascade induced by
starvation. Taken together, this study suggests that autophagy could play a role in
placental invasion system and that nutrient starvation affects LC3B expression. 相似文献
10.
Asada Yohei Kimura Masaomi Azechi Issaku Iida Toshiaki Kubo Naritaka 《Paddy and Water Environment》2019,17(3):351-358
Paddy and Water Environment - Leakage of agricultural pipes has been increasingly frequent problems due to corrosion, loosening of joints, and cracks, which result in the subsidence of peripheral... 相似文献