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排序方式: 共有1201条查询结果,搜索用时 187 毫秒
921.
Inokuma H Makino T Kabeya H Nogami S Fujita H Asano M Inoue S Maruyama S 《Veterinary parasitology》2007,145(1-2):186-189
Numbers of feral raccoon; the possible reservoir animal of Ehrlichia and Anaplasma, are increasing in Japan. Thus serological methods were utilized to examine Ehrlichia and Anaplasma infection in raccoons from Kanagawa Prefecture, Japan. By using an indirect immunofluorescence assay, among 187 feral raccoons examined, 1 (0.5%) serologically reacted with Ehrlichia canis, 3 (1.6%) with Ehrlichia chaffeensis and 1 (0.5%) with Anaplasma phagocytophilum with the titers of 1:40 or more. Although screening PCR for Ehrlichia and Anaplasma species failed to detect the presence of ehrlichial DNA in serum samples, results of the serological tests suggested that the feral raccoons might be infected with some species of Ehrlichia and Anaplasma. 相似文献
922.
Fukuta K Orui T Tanaka K Sasaki M Endo H Ismail DB Kudo H Kimura J 《Anatomia, histologia, embryologia》2007,36(6):424-427
We examined unique erythrocyte pits of the peripheral blood and bone marrow in the lesser mouse deer, Tragulus javanicus, using scanning electron microscope (SEM) and transmission electron microscope (TEM). Under the SEM observation, the pit was observed as a hole on both mature erythrocytes of the peripheral blood and immature erythrocytes of the bone marrow. By the TEM, the mature erythrocytes had a vacuole, which showed complicated shape and occupied considerable space within the cytoplasm. The vacuole was communicated extracellularly by perforation, which corresponded to the hole on the cell surface. In the bone marrow, erythroblast and reticulocytes have a cytoplasmic vacuole. This abnormal feature of the erythrocytes is peculiar to the mouse deer, and not found in other tropical ruminants. Despite the disadvantage of volume loss from the small erythrocytes, the mouse deer were healthy and showed no signs of anaemia. 相似文献
923.
Tanaka Y Koketsu Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(12):1229-1233
The present study examined factors associated with suckling, eating and postural behaviors (standing, lying and sitting) and the relationships between sow behaviors and reproductive performance. A commercial farrowing-to-finish farm with approximately 300 female pigs was visited eight times for 3 years to record sow behaviors using time-lapse video recorders for 24 hr. The lactational and postweaning reproductive performances of each sow were recorded using a recording software system. Statistical models were built to investigate the factors associated with each behavior. Regression analyses were performed to determine the associations between behavior measurements and adjusted 21-day litter weights (A21d-Wt), weaning-to-first-mating intervals (WMI) and occurrence of >or= 2 dead piglets during lactation. The means of suckling intervals and frequency of postural changes of the 145 recorded sows were 47.5 +/- 0.59 min and 86.8 +/- 2.97, respectively. As parity increased from 1 to >or= 4, the suckling interval and total standing duration increased (P<0.05). The number of nursing piglets and observation days 4 to 21 of lactation were not associated with the suckling intervals. A longer duration of lactation was associated with a longer total standing duration and a higher frequency of postural changes (P<0.05). Shorter suckling intervals were associated with heavier A21d-Wt (P<0.05). Each change in postural behavior increased the likelihood of occurrence of >or= 2 dead piglets during lactation (P<0.05). No postural or suckling behaviors were associated with WMI. Eating behavior was not associated with any reproductive performance. In conclusion, sow behaviors during lactation were related to lactational performance but were not related to postweaning reproductive performance. 相似文献
924.
Clinical significance of circulating vascular endothelial growth factor in dogs with mammary gland tumors 总被引:2,自引:0,他引:2
Kato Y Asano K Mogi T Kutara K Teshima K Edamura K Tsumagari S Hasegawa A Tanaka S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(1):77-80
Increase in circulating vascular endothelial growth factor (VEGF) is suggested as a prognostic indicator in human patients with malignant tumors. The purpose of this study was to evaluate the clinical significance of circulating VEGF in dogs with mammary gland tumors (MGT). Both plasma and serum VEGF were significantly higher in dogs with MGT when compared with those in the healthy dogs. In dogs with MGT, the plasma and serum VEGF of the malignant group increased significantly compared with those of the benign group. Additionally, there was a significant difference between the plasma and serum VEGF in the groups with postoperative metastasis and no metastasis. Circulating VEGF is expected to be clinically available for the determination of prognosis in canine MGT. 相似文献
925.
Tsuyoshi Shimmura Yuji Maruyama Saori Fujino Eriko Kamimura Katsuji Uetake Toshio Tanaka 《Animal Science Journal》2015,86(2):214-220
We reported previously that behavioral development of chicks was promoted remarkably by the presence of a broody hen. Here we report that these effects at an early age persist after maturity. A total of 60 female chicks were randomly assigned to one of two treatment groups: six pens with five chicks (brooded group) each were reared by a broody hen and six pens with five chicks (non‐brooded group) each were provided with an infrared heating lamp. We evaluated the persistent effects of broody hens by measures of behavior, physical condition and production at 9, 16, 35 and 55 weeks of age. The numbers of threatening, aggressive pecking, fighting and severe feather pecking behaviors were higher in non‐brooded than in brooded chickens (all P < 0.05). Egg production was lower in brooded than in non‐brooded chickens (P < 0.05), while the number of brooding chickens was higher in the brooded than in the non‐brooded group (P < 0.05). In conclusion, the presence of broody hens at an early stage of chicks' lives has a persistent effect on behavior. Although brooded chickens showed more brooding and lower egg production than non‐brooded chickens, feather pecking and aggressive interaction were decreased in brooded hens. 相似文献
926.
Summary The one-electron oxidation activity of brown-rot fungi was determined by measuring ethylene production from KTBA. Ethylene
production was related to degradation of lignin, cellulose, and wood itself. Extracellular protein that catalyzed oxidation
of KTBA was isolated from wood-containing cultures. This protein required H2O2 for KTBA oxidation. It was also found to oxidize NADH, producing H2O2 via
in the presence of O2. The protein showed little phenol-oxidase activity under conditions giving high activity against KTBA. The results indicate
that partially reduced oxygen may play a role in the initial degradation of the cellulose and lignin in wood in cultures of
brown-rot fungi. 相似文献
927.
Masaru Tanaka Yasuhiro Takahata Hiroki Nakayama Masaru Yoshinaga Toru Kumagai Makoto Nakatani 《Scientia Horticulturae》2010
To develop a simple and reliable method to identify sweetpotato cultivars, we designed cleaved amplified polymorphic sequence (CAPS)-based markers and used them to perform genotyping of Japanese sweetpotato cultivars. In order to screen the CAPS-based markers, 13 primer pairs were designed from the exon sequences of 11 sweetpotato genes to amplify fragments containing an intron. By digesting the amplified products with 8 restriction enzymes having different recognition sites, a total of 27 polymorphic marker fragments were obtained. Genotyping of 60 Japanese sweetpotato cultivars using these markers suggested that the markers can effectively distinguish sweetpotato cultivars. Among the genes used for primer design, the gene encoding the dihydroflavonol 4-reductase (DFR) showed the largest degree of polymorphism. To our knowledge, this is the first report on the development of CAPS-based markers in sweetpotato. 相似文献
928.
A new eastern blotting technique has been established for ginsenoside Re (G-Re) contained in American ginseng berry pulp extracts. G-Re in American ginseng berry pulp was extracted using 100% methanol, 100% ethanol, 50% aqueous methanol, and 50% aqueous ethanol. The combined crude extracts were applied onto a polyethersulfone membrane and developed using the methanol–water–acetic acid solvent system (45:55:1 v/v). Separated components were immunostained using anti-G-Re monoclonal antibody. G-Re was first specifically detected and then quantitatively analyzed using NIH Imaging software. We also confirmed that the most suitable solvent was 50% aqueous methanol for extracting G-Re from American ginseng berry pulp. 相似文献
929.
In our efforts to find new whitening agent from natural resources, we focused on wood of Artocarpus heterophyllus which shows anti-melanogenesis activity. By activity-guided fractionation of A. heterophyllus wood extract, a new prenylated flavonoid, 3-prenyl luteolin (1) was isolated. The IC50 of mushroom tyrosinase inhibitotry activity of 1 was 76.3 µM. The results of the comparison with that of luteolin showed the prenyl substituent at C-3 position of 1 play an important role for revealing tyrosinase inhibition. In melanin formation inhibition on B16 melanoma cells, IC50 of 1 was 56.7 µM with less cytotoxicity. 相似文献
930.
Ayumi Tanaka-Oda Tanaka Kenzo Satomi Koretsune Haruto Sasaki Kenji Fukuda 《Forest Ecology and Management》2010
On the Loess Plateau, China, several planted tree species such as Populus hopeinsis and Robinia pseudoacacia suffer occasional diebacks in the top shoots, reducing growth rates after maturation. However, this does not usually occur in other species, e.g., Ulmus pumila and Zizyphus jujuba. We compared stable carbon isotope ratios (δ13C) as indicators of leaf water-use efficiency (WUE), leaf mass per unit area (LMA), and leaf area- and mass-based nitrogen content (Narea and Nmass) by tree height (1, 5, and 10 m) in P. hopeinsis, R. pseudoacacia, U. pumila, and Z. jujuba. In P. hopeinsis and R. pseudoacacia, leaf δ13C and Narea were significantly lower in 10-m trees than in 1-m saplings, indicating that leaf WUE and photosynthetic rates of both species decreased with tree height. In contrast, δ13C in Z. jujuba varied little with tree height. The δ13C of 10-m-tall U. pumila trees was significantly higher than that of 1-m plants, demonstrating an increase in WUE with tree height. Decreasing WUE, leaf Narea, and Nmass with height increases in P. hopeinsis and R. pseudoacacia may be related to water and nutrient limitations for these species in semiarid regions. In contrast, stable or increasing δ13C with tree height in U. pumila and Z. jujuba may account (to some extent) for successful production of these species under identical environmental conditions. Diameter growth rate also decreased with maturity in P. hopeinsis and R. pseudoacacia, but increased or was stable for U. pumila and Z. jujuba. The differences in leaf WUE and LMA among species with tree maturity may be related to species’ growth patterns and susceptibility to drought stress, and are likely to be important new criteria for plantation species selection on the Loess Plateau. 相似文献