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31.
Masuda K Sakaguchi M Saito S Deboer DJ Yamashita K Hasegawa A Ohno K Tsujimoto H 《Veterinary dermatology》2002,13(1):55-61
Three dogs were examined because of episodes of recurrent pruritic dermatitis in the spring, the season of Japanese cedar (Cryptomeria japonica, CJ) pollination in Japan. The dogs were shown to be sensitive to CJ pollen allergen using intradermal testing and antigen-specific IgE measurement. Fluorometric enzyme-linked immunosorbant assay (ELISA) showed increased concentrations of IgE specific to Cry j 1 and a negative result for Cry j 2 in the three dogs. The concentrations of IgE specific to Cry j 1 during the season of CJ pollination were higher than the concentrations found during the off-season in all the dogs, and the variation in the concentrations correlated with the variation in clinical signs. Peripheral blood mononuclear cells showed apparent proliferative responses to crude CJ pollen antigen and Cry j 1 during CJ pollination season. These findings indicated that Cry j 1 was the major allergen recognized by IgE and lymphocytes and resulted in the development of type I hypersensitivity to CJ pollen allergen in these atopic dogs. 相似文献
32.
Saito M Kubo M Itagaki H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(11):1209-1211
Sarcocystis sp. was detected from cattle slaughtered in Saitama Prefecture, Japan. The cysts were 3,400-4,400 x 198-238 microm in size and had the thick cyst wall which was 7 to 10 microm thick and provided with finger-like villar protrusions. The protrusions were 8-9.5 x 2-2.5 microm in size and had microtubules in the core. 相似文献
33.
Kiriko Nakamura Kiyoshi Matsubara Hitoshi Watanabe Hisashi Kokubun Yoshihiro Ueda Naomi Oyama-Okubo Masayoshi Nakayama Toshio Ando 《Scientia Horticulturae》2006
In order to identify genetic resources for breeding fragrant petunias for use as bedding plants, volatile compounds released by day from the flowers of 40 commercial Petunia hybrida cultivars were analyzed using a solid-phase micro-extraction technique coupled with GC–MS. The three cultivars with solid deep-blue flowers that accumulate malvidin in corollas with high tissue pH were found to emit abundant iso-eugenol as the principal floral fragrance. Several other cultivars that emitted considerable amounts of methylbenzoate and/or benzylbenzoate from the flower were also identified. Association between the floral fragrance and the other floral traits such as floral anthocyanin composition and corolla-tissue pH was discussed. 相似文献
34.
T Hohdatsu N Takahasi S Ide H Yamagishi H Saito Y Fujisaki H Koyama 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(3):519-526
The relation among biological properties, particularly pathogenicity for suckling mice, and plaque size was studied in four virus strains: Getah virus strain Kanagawa; two strains obtained by plaque cloning of the Kanagawa strain, Getah Kanagawa SP (G-K-SP) strain which forms small plaques (SP) only and strain G-K-LP which forms large plaques (LP) only; and strain Haruna which forms SP only. There were no marked differences among the four strains in serological properties, growth curves and sensitivity to pH, trypsin and temperature. Strain G-K-LP showed higher pathogenicity for suckling mice than strain G-K-SP. However, the pathogenicity of strain Haruna, which forms SP only, was as high as that of strain G-K-LP. Some of the clones in SP of strain Kanagawa kill all mice in 5 to 6 days after inoculation while the others required 9 to 11 days or longer before causing death. The present study showed that the pathogenicity of Getah viruses shortly after being isolated from the field, such as the Kanagawa strain, is different between large and small plaques, and even among small plaques, at least in suckling mice, and that the pathogenicity has no relation to plaque size. 相似文献
35.
This study proposes a methodology for forecasting crop yields at intermediate times in the growing season using Markov chain theory. A Markov chain is constructed, based on historical data, to provide forecast distributions of crop yield for various crop and soil moisture condition classes at selected times prior to harvest. Expected yield and the associated standard error are obtained for each condition class. The methodology is compared to a regression approach in which the independent variables are the various crop and soil moisture conditions. The Markov chain approach requires less stringent assumptions and provides more information than the regression approach. However, the potential loss of precision in the forecast using this approach requires separate evaluation for each application. A data base created by the CERES-Maize model, which simulates the growth and development of a corn crop, is used to demonstrate the development of the forecast yield distributions using the Markov chain approach. 相似文献
36.
M Suzuki K Sitizyo T Takeuchi T Saito 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(5):1077-1087
Electroencephalogram (EEG) examinations were carried out on three Japanese Black calves (1, 2 and 14 week old) affected with cerebrocortical necrosis (CCN) in order to investigate the relationship between EEG abnormalities and encephalic lesions. Some neurologic signs such as circling, astasia, convulsion and opisthotonus appeared in two of the calves (case 1 and 3). The other calf (case 2), however, showed no neurologic signs. The EEGs obtained from the two calves (case 1 and 2), in the awake state, showed constant high amplitude (50-160 microV) and slow (1-4 Hz) activity (HASA). One of these (case 1) had necrosis mainly in the right hemisphere and showed a markedly asymmetric sharp wave. On the other hand, in case 3, the EEG showed diffuse lowered activity, and almost flat in some leads. A decrease in fast activity observed in common with all three animals. These findings suggest that one of the characteristic EEG patterns of CCN patient may be HASA and decreased fast activity. Histopathologic diagnoses of the calves were CCN in various degrees. The degrees of abnormality of the EEGs seemed to accord with the seriousness of the lesions. Because the EEG obtained from the calf having no obvious neurologic signs showed an abnormal pattern, it was considered that EEG examinations in the early stages of disorders are valuable to diagnose CCN. 相似文献
37.
To clarify mechanisms underlying variation in transpiration rate among deciduous broad-leaved tree species, we measured diurnal changes in stomatal conductance (gs) and leaf water potential, and calculated the maximum transpiration rate (Emax), leaf-specific hydraulic conductance (K(s-l)) and difference between the soil water potential and the daily minimum leaf water potential (Psis - Psi(l,min)). Pressure-volume (P-V) measurements were made on leaves. Saplings of eight broad-leaved tree species that are common in Japanese cool temperate forests were studied. Maximum transpiration rate varied significantly among species. There was a statistically significant difference in Psis - Psi(l,min), but not in K(s-l). Species with large Emax also had large Psis - Psi(l,min) and gs. The results of the P-V analyses showed that species with a large Psis - Psi(l,min) maintained turgor even at low leaf water potentials. The similar daily minimum leaf pressure potentials (Psip) across all eight species indicate that Psip values below this minimum are critical. Based on these results, we suggest that the leaf cell capacity for turgor maintenance strongly affects Psis - Psi(l,min) and consequently Emax via stomatal regulation. 相似文献
38.
Seiichi Kanetani Mitsuteru Akiba Katsunori Nakamura Koichiro Gyokusen Akira Saito 《Journal of Forest Research》2001,6(4):307-310
The process of decline of an endangered tree species,Pinus armandii var.amamiana, was monitored on the southern slope of Mt. Hasa-dake in Yaku-shima Island from 1994 to 1998. There are 163 trees ofP. armandii var.amamiana over 1.3 m in height. They are distributed on steep ridges and rocks with a thin soil layer mostly consisting of friable
granite. During the monitoring period, 21 trees ofP. armandii var.amamiana died and the mortality rate was 12.9%. Dead trees were categorized into three types: standing, uprooted and landslide. The
uprooted- and landslide-typed dead trees were found only after a severe typhoon struck Yaku-shima Island. This suggests that
the combination of fragile site conditions and severe typhoons play an important role in the process of decline ofP. armandii var.amamiana. The standing-typed dead trees were presumed to have been killed by pine wilt disease, accounting for 71.4% of the dead trees.
However,Bursaphelenchus xylophilus, the cause of pine wilt disease, was not detected from any of the wood chips or branch samples from the standing-typed dead
trees ofP. armandii var.amamiana. This might indicate that some factor(s) other than pine wilt disease could be responsible for the standing-typed death ofP. armandii var.amamiana in natural habitats.
A part of this paper was presented at the 109th Meeting of the Japanese Forestry Society. 相似文献
39.
To find plus tree clones of Cryptomeria japonica that are heterozygous for a male-sterility gene (Aa), we crossed a homozygous male-sterile tree (aa) with 63 clones. Male sterility in this case is controlled by a recessive allele at a single gene locus and is expressed only in homozygotes. All F1 seedlings obtained by crossing the male-sterile mother tree and 62 out of the 63 clones produced pollen. In contrast, F1 seedlings obtained from the crossing between the male-sterile mother tree and a plus tree clone, Ohara 13, produced 64 male-sterile individuals and 52 fertile individuals. The segregation ratio fitted the expected 1 : 1 ratio according to a chi-square test. These results clearly demonstrate that the Ohara 13 clone is heterozygous for a male-sterility gene. 相似文献
40.
A carbonaceous sorbent was prepared from the wood of Japanese larch (Larix leptolepis) by dehydration with concentrated sulfuric acid in a 69% yield. The abilities of the sorbent to remove Cr(VI) from aqueous
solutions were investigated. Research parameters included the initial solution pH, temperature, and initial concentration
of Cr(VI) in solution. The removal of Cr(VI) was highly solution pH dependent and was mainly governed by physicochemical sorption
under weak acidic conditions. The equilibrium data fit well in the Langmuir isotherm model. The Langmuir constants were calculated
at different temperatures, and the sorption capacity increased with rising temperature, indicating the endothermic nature
of the Cr(VI) sorption onto the sorbent. The desorption experiments suggest that the Cr(VI) sorption is generally irreversible,
owing to strong interaction of HCrO
4
−
with the active sites of the sorbent. 相似文献