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1.
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   
2.
Monoclonal integration of bovine leukemia virus (BLV) proviral DNA into bovine genomes was detected in peripheral blood from two clinical cases of enzootic bovine leukosis (EBL) without enlargement of superficial lymph nodes. A BLV-specific probe hybridized with 1 to 3 EcoRI and HindIII fragments in these 2 atypical EBL cattle by Southern blotting and hybridization, as well as in 3 typical EBL cattle. The probe also hybridized to a large number of EcoRI and HindIII fragments in 5 cattle with persistent leukosis. These results suggest that the detection of monoclonal integration of BLV provirus into the host genome may serve as a marker of monoclonal proliferation and malignancy in difficult to diagnose EBL cattle.  相似文献   
3.
Summary A new lignin isolation method has been developed. Wood and pulp were subjected to ball milling, swelled in an organic solvent, and then treated with a cellulase. The enzyme digestion time could be shortened to 1 day with this method. The lignin obtained has been named Swelled Enzyme Lignin (SEL). Swelling and enzyme digestion conditions and their effects on lignins were investigated. The SEL's from wood could be directly washed with water, while those from pulp had to be washed with aqueous acetic acid because they were water soluble. The purification of crude SEL's was accomplished by extracting them with dioxane-water, and then precipitating and washing with ethyl ether. Lignin yields were 24–67% based on the total amount of lignin present. The characteristics of the SEL's were further investigated by gel-permeation chromatography (GPC), infrared and 13C nuclear magnetic resonance (NMR) spectroscopy.Symbols SUKP Softwood Unbleached Kraft Pulp - BUKP Birch Unbleached Kraft Pulp - TD Todomatsu (Abies sachalinensis) wood - MWL Milled Wood Lignin - MWLS (BK, TD) Milled Wood Lignin of SUKP (BUKP, TD) - SEL-C Swelled Enzyme Lignin (crude) - SELS-C SEL-C of SUKP, other materials named in the same way - SELS-90 SEL-C of SUKP and extracted with 90% dioxane-water - SELS-96 SEL-C of SUKP and extracted with 96% dioxane-water, other materials named in the same way  相似文献   
4.
Adsorption behavior of heavy metals on biomaterials   总被引:8,自引:0,他引:8  
We have investigated adsorption of Cd(II) and Pb(II) at pH 2-6.7 onto the biomaterials chitosan, coffee, green tea, tea, yuzu, aloe, and Japanese coarse tea, and onto the inorganic adsorbents, activated carbon and zeolite. High adsorptive capabilities were observed for all of the biomaterials at pH 4 and 6.7. In the adsorption of Cd(II), blend coffee, tea, green tea, and coarse tea have comparable loading capacities to activated carbon and zeolite. Although activated carbon, zeolite, and chitosan are utilized in a variety of fields such as wastewater treatment, chemical and metallurgical engineering, and analytical chemistry, these adsorbents are costly. On the other hand, processing of the test biomaterials was inexpensive, and all the biomaterials except for chitosan were able to adsorb large amounts of Pb(II) and Cd(II) ions after a convenient pretreatment of washing with water followed by drying. The high adsorption capability of the biomaterials prepared from plant materials is promising in the development of a novel, low-cost adsorbent. From these results, it is concluded that heavy metal removal using biomaterials would be an effective method for the economic treatment of wastewater. The proposed adsorption method was applied to the determination of amounts of Cd(II) and Pb(II) in water samples.  相似文献   
5.
6.
During defense responses, plant cells produce nitric oxide (NO), which may control many physiological processes. In a previous study, we reported that nitrate reductase (NR) is responsible in part for INF1 elicitor-induced NO production in Nicotiana benthamiana, but the possibility remains that other NO-generating system(s) contribute to NO production. In mammalian cells, NO production is catalyzed by NO synthase (NOS). However, NOS-like enzyme(s) have never been identified in plants, and only the gene for Arabidopsis thaliana nitric oxide-associated 1 (AtNOA1) has been identified as a putative regulator of NOS activity in plants. In this study, we cloned NbNOA1, a homolog of AtNOA1, from N. benthamiana and investigated its involvement in NO production induced by INF1. The NbNOA1 gene was silenced by a virus-induced gene-silencing (VIGS) technique. NbNOA1-silenced plants had yellowish leaves. Silencing NbNOA1 partially decreased INF1-induced NO production, while overexpressing NbNOA1 did not affect NO production. Silencing NbNOA1 suppressed INF1-induced PR1a gene expression and increased susceptibility to Colletotrichum lagenarium. These results suggest that NbNOA1 is involved in INF1-mediated NO production and is required for defense responses. The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession number AB303300.  相似文献   
7.
Ultrapure soft water (UPSW) is water in which calcium and magnesium ions have been replaced with sodium ions using a cation‐exchange resin. We recently demonstrated that washing with soap and UPSW reduced the clinical severity of dermatitis and improved the skin barrier function in NC/NgaTnd mice, a murine model for human atopic dermatitis. The purpose of this pilot study was to evaluate the efficacy of shampoo treatment with UPSW for dogs with pruritus. Eleven dogs with pruritus were randomly assigned to two groups depending on whether they received weekly shampoo treatment with UPSW or tap water for 4 weeks. After a washout period, the treatment protocol was switched such that each dog received both treatments. The pre‐treatment and post‐treatment values of the following were compared: pruritus scores assessed by the owners; dermatitis scores recorded by an investigator; and transepidermal water loss (TEWL). Shampoo treatment with UPSW significantly decreased pruritus and dermatitis scores in the dogs, whereas shampoo treatment with tap water did not. In addition, shampoo treatment with UPSW, but not with tap water, significantly reduced TEWL in the dogs. Adverse events due to the treatment were not observed in the dogs. Furthermore, we found that topical application of UPSW for barrier‐disrupted skin caused by tape stripping in healthy dogs decreased TEWL more rapidly than topical application of tap water. Our findings suggest that shampoo treatment with UPSW promotes skin barrier recovery and thus could be considered as a possible therapeutic option in the management of pruritus and dermatitis in dogs.  相似文献   
8.
Leaf photosynthetic potential, a major determinant of yield potential in rice, is mostly explained by stomatal conductance (gs) as well as leaf N content (Rubisco protein content). Therefore, the rapid and precise evaluation of gs as well as leaf N content would be a valuable addition to rice breeding programs aimed at improved yield potential. We established a simple method based on infrared thermography to estimate varietal differences in gs. Seven rice varieties were cultivated in two-row plots in 2007, and canopy temperatures in three varieties, including a control variety, Koshihikari, were simultaneously measured to determine canopy temperature difference (CTd) between Koshihikari and the other varieties on clear days. The varieties Takanari, Habataki, and TUAT1-5-6a displayed significantly (P < 0.05) lower leaf temperature and higher gs and leaf photosynthetic rate (Pn) than Koshihikari. CTd was closely correlated with gs and Pn. These results indicate that CTd may be useful as a relative index to estimate varietal differences in gs. A significant CTd was still observed even under cloudy conditions in 2008. Takanari and TUAT1-5-6a had lower leaf temperature than Koshihikari on cloudy days as well as on clear days. Subsequent investigation of photosynthetic light response curves revealed that Takanari and TUAT1-5-6a had higher gs and Pn than Koshihikari under lower irradiance. These results suggest that infrared thermography may be a simple method of evaluating varietal differences in gs through CTd, and that it may be practicable even under cloudy conditions.  相似文献   
9.
One of the difficulties to rear Anguilla japonica larvae is the frequent occurrence of notochord deformities. We tested the effect of salinity on the occurrence of the deformities, because we have been using 50 % diluted seawater (50 % SW) for glass eel production, on the basis of the fact that intermediate salinity saves energy due to lower cost for osmoregulation and contributes higher survival and growth rates. We reared 6-day-old larvae in 50 and 100 % SW for 85 days and observed their morphology. The occurrence rate of deformed larvae, including kyphosis and scoliosis, was significantly higher in 50 % SW (35.8 %) than in 100 % SW (25.4 %), while survival rate was significantly higher in 50 % SW (69.8 %) than in 100 % SW (32.3 %) and growth in 50 % SW (mean body depth: 7.9 ± 5.3 mm) was better than in 100 % SW (6.8 ± 4.6 mm). We speculate that the most of severely deformed larvae could not survive in the tougher condition of 100 % SW, showing the lower occurrence of deformed larvae. Eventually, the yield of normal larvae after 85 days rearing was 1.9-fold higher in 50 % SW than in 100 % SW, implying that the advantage of 50 % SW for rearing eel larvae outweighs the risk of deformities.  相似文献   
10.
ABSTRACT:   Gnomefish Scombrops boops and Scombrops gilberti are commercially important fishes in Japan, but these species are often confused in the markets because of their morphological similarity. To identify these two species, we performed nucleotide sequencing and restriction fragment length polymorphism (RFLP) analysis on 16S ribosomal RNA (rRNA) gene and the control region in mitochondrial DNA. Five and 12 nucleotide substitutions were observed between species in the 777-bp 16S rRNA gene and 471-bp control region, respectively. Diagnostic restriction sites for discriminating between S. boops and S. gilberti were found in the 16S rRNA gene, but not in the control region. Polymerase chain reaction (PCR)–RFLP analysis using two enzymes, Eco NI and Mva I, clearly discriminated between S. boops and S. gilberti identified by meristic characters. The PCR–RFLP analysis identified most of the 168 Scombrops young caught in the coastal waters of the Izu and Miura peninsulas as S. boops , suggesting that S. gilberti juveniles are rare in this area.  相似文献   
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