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排序方式: 共有741条查询结果,搜索用时 15 毫秒
1.
Paddy and Water Environment - This paper revealed the irrigation rate by groundwater, evapotranspiration (ET), total water balance and yield in the experimental rice and mung bean fields in a... 相似文献
2.
As the levels of radioactivity in seafood have fallen back into the safe range, Fukushima fisheries are considering reopening. However, even if seafood from the Fukushima area were sufficiently safe to distribute to seafood markets, its value may be undermined because of the damage done to its reputation by the Fukushima disaster. We quantified consumers’ preferences for seafood from Fukushima and adjacent prefectures to examine the extent of the reputational damage to Fukushima seafood. We conducted a choice experiment to measure consumers’ willingness to pay for seafood from the Fukushima area. We also measured the impact of displaying ecolabels [Marine Stewardship Council (MSC) and Marine Eco-label Japan (MEL)] on Fukushima products. The results indicated that Fukushima products are considerably discounted compared with products displayed as domestic; even products from adjacent prefectures are substantially discounted. By contrast, consumers positively evaluated locally labeled products. We also found that demersal fish are discounted more than pelagic fish that inhabit the ocean surface off the shore of Fukushima. 相似文献
3.
Effect of monensin withdrawal on rumen fermentation,methanogenesis and microbial populations in cattle 下载免费PDF全文
Arfan Abrar Takamitsu Tsukahara Makoto Kondo Tomomi Ban‐Tokuda Wang Chao Hiroki Matsui 《Animal Science Journal》2015,86(9):849-854
This study was designed to obtain information on the residual influence of dietary monensin on ruminant fermentation, methanogenesis and bacterial population. Three ruminally cannulated crossbreed heifers (14 months old, 363 ± 11 kg) were fed Italian ryegrass straw and concentrate supplemented with monensin for 21 days before sampling. Rumen fluid samples were collected for analysis of short chain fatty acid (SCFA) profiles, monensin concentration, methanogens and rumen bacterial density. Post‐feeding rumen fluid was also collected to determine in vitro gas production. Monensin was eliminated from the rumen fluid within 3 days. The composition of SCFA varied after elimination of monensin, while total production of SCFA was 1.78 times higher than on the first day. Methane production increased 7 days after monensin administration ceased, whereas hydrogen production decreased. The methanogens and rumen bacterial copy numbers were unaffected by the withdrawal of monensin. 相似文献
4.
Analysis of genomic mutation and immunohistochemistry of platelet‐derived growth factor receptors in canine vascular tumours 下载免费PDF全文
S. Abou Asa T. Mori K. Maruo A. Khater A. El‐sawak E. Abd el‐Aziz T. Yanai H. Sakai 《Veterinary and comparative oncology》2015,13(3):237-245
We examined whether mutation of the platelet‐derived growth factor receptor protein tyrosine kinase (PDGFR)‐α and PDGFR‐β genes contributes to their overexpression in canine vascular tumours. Genomic sequences of trans‐ or juxtamembrane regions of PDGFR‐α and PDGFR‐β were analysed with immunohistochemical staining and polymerase chain reaction‐direct sequencing using DNA from paraffin‐embedded neoplastic tissues of 27 hemangiosarcomas (HSAs) and 20 hemangiomas (HAs). Immunohistochemically, 75% of the HA cases were positive for PDGFR‐α and almost most of the HA cases were negative for PDGFR‐β. Of the HSA cases, 55.6% were negative for PDGFR‐α and 63% were strongly positive for PDGFR‐β. Among the HA cases, 1 missense mutation was detected in PDGFR‐α exon 18 and 1 in PDGFR‐β exon 17. Two HSA cases had missense mutations in exon 14 and 1 in exon 17 of PDGFR‐β. Thus, genomic mutation of trans‐ or juxtamembrane regions of PDGFRs was not the main mechanism driving the activation of receptors in HSA and HA. 相似文献
5.
Weak activity of UDP-glucuronosyltransferase toward Bisphenol analogs in
mouse perinatal development
Risa YABUSAKI Hidetomo IWANO Sumito TSUSHIMA Nanako KOIKE Naoko OHTANI Kentaro TANEMURA Hiroki INOUE Hiroshi YOKOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1479-1484
Bisphenol A (BPA) is a widely used industrial chemical that disrupts endocrine function.
BPA is an endocrine disrupting chemical (EDC) that has been demonstrated to affect
reproductive organ development, brain development, metabolic disease and post-natal
behavior. Accordingly, Bisphenol analogs, Bisphenol F (BPF, bis (4-hydroxyphenyl) methane)
and Bisphenol AF (BPAF, 4,4-hexafluoroisopropylidene) diphenol) are used as replacements
for BPA. BPA is mainly metabolized by UDP-glucuronosyltransferase (UGT), UGT2B1, but this
effective metabolizing system is weak in the fetus. In the present study, we demonstrated
that hepatic UGT activity toward BPAF was very weak, in comparison with BPA and BPF, in
the fetus, pups and dams. Conversely, hepatic UGT activity toward BPF was very weak in the
fetus and newborn pups, and was increased to the same level as BPA post-partum. In
conclusion, BPAF possibly tends to accumulate in the fetus, because of weak metabolism
during the perinatal period, suggesting that the metabolism of individual Bisphenol
analogs requires assessment to properly gauge their risks. 相似文献
6.
7.
Yasushi Ohmachi Tomomi Imamura Mizuyo Ikeda Eriko Shishikura Eunjoo Kim Osamu Kurihara Kazuo Sakai 《Journal of toxicologic pathology》2015,28(2):65-71
To evaluate the effectiveness of sodium bicarbonate (SB) in removing uranium and protecting animals from uranium toxicity, we intramuscularly administered 1 mg/kg of uranyl nitrate to 8-wk-old male SD rats, and 20 min after administration of uranyl nitrate, the animals were given a single oral administration of SB at 0.1, 0.3 or 1 g/kg. The SB treatment at a dose of 0.3 g/kg or more raised the pH of the rats’ urine until 4 h after treatment, and it significantly reduced the uranium amounts in the kidneys at 1 day after treatment. In another experiment, rats were intramuscularly administered 1 mg/kg of uranyl nitrate, and 20 min later, the animals were treated with sodium bicarbonate (0.1 or 1 g/kg). The rats were autopsied at 1, 3 and 7 days after uranium treatment. High-dose SB resulted in a significant increase in urinary uranium excretion in the first 24 h and a reduction of uranium deposition in the kidneys and femurs, and it also significantly suppressed uranium-induced renal toxicity, as shown by both histopathology and clinical chemistry at 3 days after uranium treatment. Low-dose SB did not show such marked effects. Our findings demonstrated that the uranium decorporation effect of sodium bicarbonate was observed at the dosage showing urine alkalinization in rats and that decorporation effect of sodium bicarbonate might be beneficial if it is administered immediately after incorporation of soluble uranium. 相似文献
8.
9.
Mei Lin Neo Kah Kheng Lim Sung‐Yin Yang Giun Yee Soong Giovanni D. Masucci Piera Biondi Hin Boo Wee Hiroki Kise James D. Reimer 《水产资源保护:海洋与淡水生态系统》2019,29(6):1002-1011
- Giant clams provide and support valuable functions to coral reefs, as well as represent a sustainable resource for traditional fisheries throughout the Indo‐Pacific region. The Ryukyu Archipelago (southern Japan) is known to be the northern latitudinal limits of giant clam distribution, but there is only limited information in the literature regarding species diversity, status, and distribution in this region.
- In this study, we report findings from a rapid survey in 2016, the first of its kind for the Ryukyu Islands, to determine species distribution and abundance of giant clams (tridacnines) around Okinawa‐jima Island.
- Results indicate the presence of four species with an overall density of 5.03 per 100 m2, from most to least abundant: Tridacna crocea, Tridacna maxima, Tridacna squamosa, and Tridacna noae. The previously reported species Tridacna gigas and Hippopus hippopus were both absent from the surveys. The densities and distributions of tridacnines varied among species and sites, which are likely attributable to efforts in replenishing and protecting stocks of selected species.
- The most abundant species, T. crocea, is an important fishery species in Okinawa, and has been widely cultured and restocked to augment depleted populations. In comparison, restocking efforts for less popular species, such as T. squamosa, have been limited, and their current sizes and numbers suggest recruitment constraints.
- Given the importance of the giant clam fishery in this region and the current declines of various species (except T. crocea), further regulations should focus on the protection of larger and mature clams that function as broodstock necessary to maintain spawning and natural recruitment.
10.
Masaru Sakai Shin‐ichi Suda Taichi Okeda Ryosuke Nomura Izumi Washitani 《水产资源保护:海洋与淡水生态系统》2019,29(5):682-692
- Glossy, broad‐leaved, evergreen (lucidophyllous) forests are found mainly in humid subtropical regions of East Asia and are recognized as a biodiverse biome harbouring numerous endemic species. To date, however, few studies have considered the conservation importance of rivers draining these unique environments. In this study, lotic Odonata were used as indicators to examine factors affecting riparian forest–stream linkages in a lucidophyllous forest in south‐western Japan.
- Lotic odonates of 10 species, including seven endemic species, and their habitats were studied along 30 stream reaches with varying environmental characteristics.
- Odonate species richness was greatest in shadier reaches as well as in heterogeneous locations in larger streams. In contrast, larger streams modified by channel enlargement for flood control had few or no odonate species.
- Protecting larger streams with less human impact and streams in dense riparian forest are the best options for conserving lotic odonates and their habitats in this globally unique forest type.