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排序方式: 共有1664条查询结果,搜索用时 15 毫秒
1.
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
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S Agungpriyono Y Yamamoto N Kitamura J Yamada K Sigit T Yamashita 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(6):1063-1069
The stomach of the lesser mouse deer (Tragulus javanicus) was observed macroscopically. It consisted of only three compartments, rumen, reticulum and abomasum without omasum. The rumen was S-shaped with large ventral and caudoventral blind sacs and the reticulum was larger than the abomasum. Internally, the rumen was covered with numerous ruminal papillae even on the pillars and the ruminoreticular fold. These papillae were leaf- or tongue-like shaped and varied in size and density. The reticulum had honey-combed crests and the secondary crests were found rarely. The lips of the reticular groove were prominent and more developed in the aboral part than in the oral one. A sac-like transition zone, which had more prominent mucosal folds than had the floor of the reticular groove, was observed between the caudal end of the reticular groove and the abomasum. Mucosal folds of the abomasum were spiral, low but rather thick. These findings were discussed in view of comparison with other ruminants and of possible functional implications. 相似文献
4.
Takaki Waritani Yoko Okuno Yoshinori Ashida Ryo Tsuchiya Kosaku Kobayashi Takatsugu Yamada 《Veterinary immunology and immunopathology》2001,80(3-4):333-338
Canine cationic trypsin was purified by salting-out, gel filtration and affinity chromatography. Purity was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight was ca. 28 kDa by SDS-PAGE.
Thirty hybridomas were obtained which produced mAb to canine cationic trypsin by the cell fusion technique. Twenty-two of these recognized cationic trypsin only, while eight hybridomas recognized both cationic and anionic trypsin. Several of the anti-canine cationic trypsin mAb were purified by salting-out and DEAE ion-change chromatography using ascites fluid of immunized BALB/c mice. The mAb proved to have very high specificity to canine cationic trypsin as shown by immunoblotting and it may be possible to use them to develop clinical assays. 相似文献
5.
Jezie A. Acorda DVM Magr Haruo Yamada DVM DVSc Seyed Mehdi Ghamsari DVM 《Veterinary radiology & ultrasound》1994,35(3):196-200
Ultrasonography of the liver was performed in 200 Holstein-Friesian dairy cattle using a 3.5 MHz transducer with a linear array electronic scanner. Liver samples were taken, processed and examined microscopically and the fat occupying rate was calculated. The hepatic ultrasonograms were evaluated according to the presence of bright pattern, dark pattern, deep attenuation, vascular blurring and blurring of edges. Of the 200 animals, 96 had a normal liver, 63 had hydropic degeneration of the liver, 37 had fatty infiltration of the liver, 3 had liver dystrophy and I had hepatic amyloidosis, diagnosed through histopathological examination. Amyloidosis was characterized by bright pattern and blurring of edges. Liver dystrophy had higher percentages of bright pattern and blurring of edges than normal liver. Hydropic degeneration had higher percentages of dark pattern and blurring of edges than normal liver. Fatty infiltration had higher percentages of bright pattern, deep attenuation, vascular blurring and blurring of edges than normal liver. The present results suggest that different ultrasonographic patterns can be observed in various diffuse hepatocellular disorders in dairy cattle 相似文献
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8.
Takeshi SHINOGI Tomoko SUZUKI Yoshihiro NARUSAKA Pyoyun PARK 《Journal of General Plant Pathology》2002,68(1):38-45
The rapid generation of reactive oxygen species (ROS), called the oxidative burst, is one of the earliest host responses to
pathogen infection or elicitor treatments. Therefore, we looked for the induction of ROS generation in Japanese pear leaves
by the host-specific toxin, AK-toxin I using a cytochemical method for detecting H2O2. A small amount of non-specific generation of H2O2 was found in the cell walls in toxin- and water-treated susceptible and resistant leaves. Thus, the generation of H2O2 at cell walls appears to be caused by wounding stress during sampling. Specific generation of ROS, however, was found only
in the membrane fragments and extended desmotubules characteristic of modified sites of the plasma membrane in the toxin-treated
susceptible leaves. In addition, generation of H2O2 at plasma membranes was observed with higher frequency in toxin-treated susceptible leaves. This result indicates that the
H2O2 generation was associated with damaged sites in the plasmalemma after toxin treatment and perhaps with the formation of membrane
fragments from altered portions of the invaginated plasma membrane.
Received 21 September 2001/ Accepted in revised form 25 October 2001 相似文献
9.
Takeshi Shinogi Tomoko Suzuki Takayuki Kurihara Yoshihiro Narusaka Pyoyun Park 《Journal of General Plant Pathology》2003,69(1):7-16
Reactive oxygen species (ROS) generation was examined in the interaction of Alternaria alternata Japanese pear pathotype and host plants using three methods: nitro blue tetrazolium (NBT) method for microscopic detection
of O2
−, diaminobenzidine (DAB) methods for microscopic detection of H2O2, and cerium chloride methods for ultrastructural detection of H2O2. ROS generation was detected by NBT and DAB methods at appressoria on leaves of susceptible cultivars and heat-shocked leaves
of resistant cultivars but not in leaves of resistant cultivars. Ultrastructural detection by the cerium chloride method identified
ROS generation at cell walls of appressoria and penetration pegs in susceptible, resistant leaves and heat-shocked leaves.
These differences in the ultrastructural and microscopic data in resistant areas were due to the restriction of ROS generation
in limited areas, the side facing the plant surface, of appressoria and penetration pegs. Therefore, ROS generation was apparently
induced regardless of the resistance or susceptibility of the cultivar with the difference being in the volumes generated.
After evaluating the pathological role of ROS generation in fungal structures, such generation was found to be associated
with early penetration of cell walls in pear plants. Additionally, ROS generation in plants was also found in degrading pectin
layers near infected hyphae and in plasma membrane modification sites in susceptible leaves but not in resistant leaves. ROS
generation in susceptible leaves might be accompanied with plasma membrane damage, although the role of ROS generation in
the pectin layers is not clear. ROS generation in both fungal and plant cells during their interaction was likely associated
with the expression of susceptibility.
Received: June 3, 2002 / Accepted: July 31, 2002 相似文献
10.
Oriental persimmon (Diospyros kaki) originated in Eastern Asia, and many indigenous cultivars have been developed in China, Japan, and Korea. These cultivars are classified into four groups based on their natural astringency loss on the tree and seed formation: pollination-constant non-astringent (PCNA), pollination-variant non-astringent (PVNA), pollination-constant astringent (PCA), and pollination-variant astringent (PVA). PCNA is the most desirable type because the fruit can be eaten without any postharvest treatment; therefore, one of the goals of our persimmon breeding programs is to release superior PCNA cultivars. The PCNA genotype is recessive to the other three non-PCNA genotypes, and PCNA-type F1 offspring are obtained exclusively from crosses among PCNA genotypes. Moreover, the number of superior PCNA cross-parents have been limited. In the late 1980s, inbreeding depression became obvious, especially in terms of fruit size, tree vigor, and productivity. To mitigate the inbreeding, a backcross program using PCNA [(non-PCNA × PCNA) × PCNA] was started in 1990. This process, however, was inefficient because only 15% of the offspring were PCNA, and all offspring had to be grown to the fruiting stage. Therefore, molecular markers linked to the PCNA locus were developed for discriminating PCNA offspring. A molecular marker linked to Chinese PCNA has also been developed. 相似文献