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排序方式: 共有304条查询结果,搜索用时 532 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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Minimal Set of Metabolic Pathways Suggested from the Genome of Onion Yellows Phytoplasma 总被引:1,自引:0,他引:1
4.
Masaki Hiraki Wim J. Vredenberg Jack J.S. van Rensen Ko Wakabayashi 《Pesticide biochemistry and physiology》2004,80(3):183-191
Chlorophyll fluorescence induction curves of isolated thylakoids were measured in the absence and in the presence of various concentrations of photosystem II-inhibiting herbicides. A mathematical program was applied to simulate the curves. Based on these simulated curves a new method is developed to determine the concentration effect (pI50) of the herbicides. The results of the new method correspond well with reported values in the literature. The method is very convenient and time-saving. 相似文献
5.
Yokoo M Shimizu T Kimura N Tunjung WA Matsumoto H Abe H Sasada H Rodriguez-Martinez H Sato E 《The Journal of reproduction and development》2007,53(2):263-270
Previous our studies have shown that CD44, the principal receptor for hyaluronan, is present on cumulus cells during oocyte maturation. Although hyaluronan-CD44 interaction has been implicated in cumulus expansion and/or oocyte maturation, the full significance of CD44 remains unknown. The objective of the present study was to further investigate the role of CD44 in cumulus expansion and oocyte maturation in pigs. We demonstrate here in that CD44 has a key role in oocyte maturation but not in cumulus expansion. Previous studies have reported the physiological significance of cumulus expansion in oocyte maturation. However, our results suggest that cumulus expansion is a necessary condition for oocyte maturation, but that it is not sufficient on its own. Furthermore, western blot analysis demonstrated that the CD44 of the in vitro-matured cumulus-oocyte complexes (COCs) had a larger molecular weight and more terminal sialic acid, which has been proven to inhibit the hyaluronan-binding ability of the receptor, than the CD44 of the in vivo-matured COCs, indicating that the hyaluronan-CD44 interactions during in vitro maturation might be insufficient compared with those in vivo. The insufficient interactions of hyaluronan-CD44 during in vitro maturation may cause the inferior capacity of fertilization and development of oocytes matured in vitro. 相似文献
6.
Arita N Yamane I Takemura N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(2):259-261
Fluoroscopy (FS)- or transesophageal echocardiography (TEE)-guided heartworm removal was carried out using flexible alligator forceps to compare the rate of worm removal. As a result, the worm removal rates were similar between the two procedures. However, the TEE-guided procedure does not involve radiation exposure, and facilitates observation of worms in the cardiac chamber and pulmonary artery. Therefore, the TEE-guided procedure is thought to be more useful than the FS-guided procedure in clinical setting. 相似文献
7.
Nakagawa K Takemura N Machida N Kawamura M Amasaki H Hirose H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(7):619-621
A spayed female mixed cat (case 1) and its female offspring, the result of a pairing between case 1 and its male sibling, were diagnosed with hypertrophic cardiomyopathy (HCM). A pedigree survey revealed that the prevalence of HCM was at least 12.5% in the family, which was considered to be significantly higher than that in a hospital-based population (approximately 1.6%). Thus, this finding seems to support the suspected occurrence of familial HCM in this group of related cats. 相似文献
8.
Yuichi Ozaki Hiromi Okumura Yukinori Kazeto Toshitaka Ikeuchi Shigeho Ijiri Masaki Nagae Shinji Adachi and Kohei Yamauchi 《Fisheries Science》2000,66(6):1115-1122
SUMMARY: Pituitary, thyroid gland and gonads in leptocephali of Japanese eel Anguilla japonica (19.8–32.6 mm in total length), A. obscura (45.0 mm), and A. bicolor pacifica (49.5 mm) and those in glass eels of the Japanese eel were histologically and immunohistochemically examined in order to observe the developmental changes of these endocrine organs in the Anguillidae. The pituitary, consisting of adenohypophysis and neurohypophysis in Japanese eel leptocephali over 22.5 mm, did not contain thyroid stimulating hormone (TSH) immunoreactive cells. Such cells were, however, detectable in the more developed pituitaries of leptocephali of A. obscura and A. bicolor pacifica and in those of glass eels. Conversely, thyroxine (T4 )-immunoreactive thyroid follicles could be detected in all specimens, both leptocephalic and glass eel. Only in glass eels, gonads were found in the body cavity, and these gonads harbored one or two primordial germ cells (PGC) per cross-section. Our results indicate that thyroid hormones (TH) production started prior to TSH production, and that TSH and TH are both secreted during the metamorphosis from leptocephalus to glass eel. Therefore, it is plausible that the TSH–TH axis is involved in the metamorphosis from leptocephalus to glass eel, but not in the early growth from preleptocephalus to leptocephalus. 相似文献
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10.
Takashi Masaki Shigeta Mori Takuya Kajimoto Gaku Hitsuma Satoshi Sawata Masuo Mori Katsuhiro Osumi Shobu Sakurai Takeshi Seki 《Journal of Forest Research》2006,11(4):217-225
The individual growth of tree diameter at breast height (dbh) is analyzed in an even-aged plantation of Cryptomeria japonica from stand age of 45 to 94 years, to examine how the growth of individual trees has been affected by the changes in spacing
resulting from thinning operations. At any age, a significant proportion (0.37–0.46) of the variation in dbh growth during
a 5–11-year period was explained by dbh at the beginning of the period, probably due to greater leaf mass of larger trees.
Next, either one-sided or two-sided competition was added to the model, by calculating the basal area (BA) of neighboring
trees around each tree within a given radius or BA for trees having larger dbh than the focal tree within the radius. After
preliminary analyses, a radius of 8 m was selected as the critical range for tree competition. Although both types of competition
explained a significant proportion (0.09–0.43) of growth variation, one-sided competition was not significant at ages greater
than 54 years. Based on the model at 45 years of age, the initial deviation of growth rate for each tree from the predicted
rate was calculated and added to the models as a third variable. This raised the coefficient of determination up to 0.50–0.74.
These findings have practical significance for forest plantation management, particularly for controlling the growth of standing
trees via thinning, to produce high-quality timber in the future. 相似文献