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1.
Daisuke Shiode Yasuzumi Fujimori Fuxiang Hu Susumu Shimizu Teisuke Miura 《Fisheries Science》2001,67(1):110-117
SUMMARY: Flume-tank experiments were performed to examine the depth response of a new type of depth-controlled gillnet. Variations of net depth were investigated as the warp was paid out and wound up for different changes of warp length, main sinker weights, and winch speeds. In most experiments, when the warp finished paying out, the net continued to descend and then ascended slightly to an equilibrium depth (overshoot phenomenon). The overshoot distance was nearly constant when the warp was wound up and increased linearly with increasing winch speed when the warp was paid out. An increase in winch speed reduced net settling time, which converged on a constant value for both paying out and winding up. 相似文献
2.
M P Yang R Goitsuka H Tsujimoto M Onuma A Hasegawa 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(4):757-761
The association of tumor-associated antigen (TAA) on the proliferation of BLV-infected lymphoblastoid B-cell lines (BL2M3 and BL312) was investigated. Flow cytometric analysis of the expression of TAA with monoclonal antibody (mAb) c143 showed high expression of TAA on the surfaces of BL2M3 and BL312 cells. A large amount of TAA was found in the culture supernatant of BL2M3 and BL312 cells as well as in the lysates of BL2M3 and BL312 cells. Culture supernatant but not lysates of BL2M3 and BL312 cells promoted the growth of either BL2M3 cells or BL312 cells. Furthermore, this growth promoting activity in culture supernatants of BL2M3 and BL312 cells was inhibited in a dose-dependent manner when cultured with mAb c143. These results suggested that TAA may be involved in the growth factor-mediated cell growth of bovine B-lymphoblastoid cell lines expressing TAA on their cell surface. 相似文献
3.
Powdery Mildew of Prairie Gentian: Characteristics,Molecular Phylogeny and Pathogenicity 总被引:3,自引:0,他引:3
OKAMOTO Jun LIMKAISANG Saranya NOJIMA Hidenobu TAKAMATSU Susumu 《Journal of General Plant Pathology》2002,68(3):200-207
In March 1999, we found prairie gentian (Eustoma grandiflorum) infected with powdery mildew in a greenhouse in Oita Prefecture, Japan. Morphological observation revealed that the causal
fungus belongs to the mitosporic genus Oidium subgenus Pseudoidium [teleomorph: Erysiphe sensu Braun and Takamatsu (2000)]. Precise taxonomic position of the fungus, however, is uncertain due to lack of the perfect stage.
We determined the nucleotide sequence of the rDNA ITS region of the fungus. Comparison of the sequence with those obtained
from DNA databases of this fungal group revealed that the sequence is identical to those of powdery mildews from garden four-o'clock
(Mirabilis jalapa) and broad bean (Vicia faba). Inoculation of an isolate from garden four-o'clock caused mildew on prairie gentian and broad bean, suggesting that the
prairie gentian mildew originates from garden four-o'clock or broad bean. Molecular phylogenetic analysis indicated a close
relationship of this fungus to Erysiphe baeumleri on Vicia spp. and E. trifolii on Trifolium pratense. From these results, we propose that prairie gentian mildew diverged from a Fabaceae-parasitic ancestor.
Received 14 March 2002/ Accepted in revised form 28 May 2002 相似文献
4.
Jutamart KONGKAPAN Saranya POAPOLATHEP Supaporn ISARIYODOM Susumu KUMAGAI Amnart POAPOLATHEP 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):259-264
Mycotoxins are secondary fungal metabolites that are typically present in grain and feed ingredients used for
animal feeds. An analytical method using LC-ESI-MS/MS was developed to quantify nine mycotoxins, consisting of
aflatoxin B1 (AFB1), AFB2, AFG1, AFG2, T-2 toxin,
deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEA) and ochratoxin A (OTA) in broiler feeds. In total,
100 samples of broiler feeds were collected from poultry farms in Central Thailand. The survey found that
AFB1 and ZEA were the most prevalent mycotoxins in the feed samples at percentages of 93% and
63%, respectively. The limit of detections (LODs) of investigated mycotoxins was 0.20–0.78
ng/g. AFB2, DON, AFG1, NIV and T-2 toxin were also detectable at low
contamination levels with percentages of 20%, 9%, 7%, 5% and 1%, respectively, whereas OTA and AFG2
were not detected in any of the feed samples. These results suggest that there is a very low level of risk of
the exposure to mycotoxins in feeds obtained from broiler farms in Central Thailand. 相似文献
5.
6.
Ohmori K Masuda K Kawarai S Yasuda N Sakaguchi M Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(8):865-867
IgE-reactive beef components were examined by an immunoblot analysis using a serum from a dog with food hypersensitivity against beef. The immunoblot analysis revealed a distinct band at approximately 66 kDa and a faint band at approximately 50 kDa. The immunoblot analysis for serum IgE reactivity to bovine serum albumin (BSA) also revealed a positive band at 66 kDa. Serum IgE reactivity to the 66-kDa protein of beef was diminished by pre-incubating the serum sample with BSA. Furthermore, a positive reaction to BSA was detected in intradermal testing in the dog. These results clearly indicated that BSA was an IgE-reactive beef component in the dog with food hypersensitivity against beef. 相似文献
7.
Enhancement of antigen-specific immunoglobulin G production in mice by co-administration of L-cystine and L-theanine 总被引:2,自引:0,他引:2
Kurihara S Shibahara S Arisaka H Akiyama Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(12):1263-1270
Supplementation with both cystine and glutamic acid increases the synthesis of glutathione (GSH), which has a marked effect on immune cell function, as compared with supplementation with either amino acid alone in human macrophages in vitro. As dietary glutamic acid is metabolized during intestinal transport, oral administration of L-theanine (gamma-glutamylethylamide), which is metabolized to glutamic acid mainly in the liver, may act as a glutamic acid donor in vivo. The present study was performed to investigate the effects of oral administration of L-cystine and/or L-theanine on GSH levels and immune responses. Co-administration of L-cystine (200 mg/kg) and L-theanine (80 mg/kg) for 11 days before immunization significantly increased the levels of total GSH in the liver 6 hr after immunization as compared with the levels in control mice. To examine the effects of administration of L-cystine and/or L-theanine on the balance of T helper (Th) 1/Th2 cell responses, the serum ratios of the Th1 cytokine, interferon (IFN)-gamma, and the Th2 cytokine, interleukin IL-10, were investigated. At 24 hr after immunization, co-administration significantly increased the IL-10/IFN-gamma ratio compared with the ratios of the control and single-administration mice. Furthermore, co-administration before primary immunization significantly enhanced serum antigen-specific IgG levels. Taken together, these findings suggest that co-administration of L-cystine and L-theanine enhances antigen-specific IgG production partly through augmentation of GSH levels and Th2-mediated responses. 相似文献
8.
Valensi Kautsar Keitaro Tawaraya Susumu Yamada Kazunobu Toriyama Kazuhiko Kobayashi 《Soil Science and Plant Nutrition》2020,66(1):144-151
ABSTRACT This study aimed at understanding whether and how long-term organic rice farming affects soil carbon (C) and nitrogen (N) stocks and their mineralization potentials in submerged rice paddies in Tochigi, Japan. An incubation experiment was carried out to assess the impacts of internal nutrient cycling after organic farming (OF) for 4–5 years (4OF), 8–9 years (8OF), and 12 years (12OF), compared with a conventional rice field (CF). Soil samples were collected at 0–15 cm and 15–20 cm in flooded rice fields after harvest in October 2013. pH and bulk density at 0–15 cm were significantly lower in 12OF fields than in CF fields (by 0.22 unit pH and 17.5%, respectively). Compared with CF, 12OF fields showed significant differences in soil organic carbon (SOC) and total nitrogen (TN), but 4OF and 8OF fields did not. In 8OF fields, the C decomposition (Co) and N mineralization (No) potentials were significantly higher (by 34.0% and 35.6%, respectively, at 0–15 cm, and by 67.1% and 24.5% at 15–20 cm) than in CF fields. Similarly, in 8OF fields at 0–15 cm, the Co:SOC and No:TN ratios were 19.8% and 23.2% higher, respectively, than in CF fields. Co, No, Co:SOC, and No:TN in 12OF fields were higher than those in CF fields, demonstrating the effects of prolonged organic rice farming. Additionally, in 12OF fields, C and N stocks were significantly higher (by 15.5% and 17.2%, respectively, at 0–15 cm, and by 4.8% and 12.1% at 15–20 cm) than in CF fields. Our findings suggest that long-term organic rice farming increases soil C and N stocks as well as C and N mineralization in Japanese Andosols. 相似文献
9.
Sakamaki K Ishizaki S Ohkubo Y Tateno Y Fujita A 《Journal of agricultural and food chemistry》2011,59(12):6667-6671
A test apple beverage made up of apple juice (20%), high-fructose corn syrup (11.5%), citric acid (0.43%), trisodium citrate (0.02%), apple-odor flavor (0.1%), and ascorbic acid (0.02%) was stored at 40 °C and then analyzed for the change of odor in the beverage. Although no thermoacidophilic bacteria (TAB) were detected, a medicinal off-flavor was perceived after the 8 weeks of storage. Model experiments on the ingredients of the test apple beverage revealed that the off-flavor compound had been formed by ascorbic acid and (E)-hex-2-enal. Synthesis and NMR (1H, 13C, HMQC, and HMBC) analyses identified the compound as 6-propylbenzofuran-7-ol. The odor quality, retention index (RI), and mass spectrum of synthetic 6-propylbenzofuran-7-ol were identical with those of the medicinal odor compound from the test apple beverage. Sensory evaluation revealed the recognition thresholds for medicinal odor were 31.4 ppb in water and 24.0 ppb in apple beverage, and the detection thresholds were 19.6 ppb in water and 8.6 ppb in apple beverage, respectively. The quantified concentration of 6-propylbenzofuran-7-ol formed in test apple beverage was 90 ppb, approximately. This concentration was well above the odor threshold, so it was concluded that the compound was the source of the medicinal off-flavor. 相似文献
10.
There has been less concern about soil mineralogical alteration than about soil physical, chemical and biological changes induced by termite nest-building activity. Furthermore, much less attention has been paid to free sesquioxides than to phyllosilicate minerals. In the present study, we conducted field morphological observations and selective dissolution analysis to characterize free sesquioxides in termite (Macrotermes bellicosus) mounds as compared with surrounding pedons in different toposequence positions, i.e., seasonally flooded valley bottom, hydromorphic fringe and well-drained upland sites. Distinctive redoximorphic features, such as surface yellowish layers on mound structures from the fringe site, indicate possible alteration of iron sesquioxide forms in the mounds due to the transportation of soil from reductive (aquic subsoil) to oxidative (epigeal mound) environments by the nest-building activity of M. bellicosus. On the other hand, the iron-soluble content in the dithionite-citrate-bicarbonate (DCB) system (Fed) was generally higher in the mound structures than at the adjacent sub-surface (Ap2) horizon at each toposequence position, while there was less difference in the content of acid ammonium oxalate (AAO) extractable iron (Feo) as compared to Fed. As a consequence, the iron activity index (Fed/Feo ratio) was found for the most part to be lower in the mound structures than in the neighboring Ap2 horizon. In addition, the content of Fed, AAO-soluble Al (Alo) and DCB-extractable Al (Ald) was significantly correlated with clay content in these soils. These findings suggest that M. bellicosus preferentially collects clay particles, probably from the clay-rich subsoils, such as the argillic horizon, which has been formed by the co-migration of phyllosilicate minerals and relatively crystalline sesquioxides. The species then likely incorporates them into the mounds, which induces an increase in the Fed content relative to that of Feo, resulting in a decreased iron activity index in the mound structures. 相似文献