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191.
To clarify if eye fatigue is lessened when looking at wood, we carried out objective examinations using a near-point ruler and also performed sensory evaluations. Visual contact target materials were a white plastic panel, a black plastic panel or a wood panel which had Japanese ash flat grain surface. Each size of the materials was 140 × 280 mm. Test subjects were 30 undergraduate and graduate students. Each subject’s visual distance to a panel was 40–50 cm. The results showed that subjects suffered from more eye fatigue when looking at white and black plastic panels compared to looking at the wood panel in objective examinations. In sensory evaluations, almost all subjective symptom items for eyes and head progressed when subjects looked at white plastic panel or black plastic panel. However, almost no progression of subjective symptoms was noted when subjects looked at the wood panel. In both objective examinations and sensory evaluations, eye fatigue was most highly associated with the black plastic panel, followed by the white plastic panel and, finally, the wood panel. 相似文献
192.
Identification of a Plasmid‐Mediated Quinolone Resistance Gene in Salmonella Isolates from Texas Dairy Farm Environmental Samples 下载免费PDF全文
K. J. Cummings L. D. Rodriguez‐Rivera K. N. Norman N. Ohta H. M. Scott 《Zoonoses and public health》2017,64(4):305-307
A recent increase in plasmid‐mediated quinolone resistance (PMQR) has been detected among Salmonella isolated from humans in the United States, and it is necessary to determine the sources of human infection. We had previously isolated Salmonella from dairy farm environmental samples collected in Texas, and isolates were tested for anti‐microbial susceptibility. Two isolates, serotyped as Salmonella Muenster, showed the discordant pattern of nalidixic acid susceptibility and intermediate susceptibility to ciprofloxacin. For this project, whole‐genome sequencing of both isolates was performed to detect genes associated with quinolone resistance. The plasmid‐mediated qnrB19 gene and IncR plasmid type were identified in both isolates. To our knowledge, this is the first report of PMQR in Salmonella isolated from food animals or agricultural environments in the United States. 相似文献
193.
Colonization of the vegetative stage of rice plants by the false smut fungus Villosiclava virens,as revealed by a combination of species‐specific detection methods 下载免费PDF全文
E. Tanaka T. Kumagawa N. Ito A. Nakanishi Y. Ohta E. Suzuki N. Adachi A. Hamada T. Ashizawa T. Ohara M. Tsuda 《Plant pathology》2017,66(1):56-66
Rice false smut disease caused by the ascomycete fungus Villosiclava virens (Clavicipitaceae) reduces rice yield worldwide. It invades rice panicles and forms dark‐green false smut balls composed of thick‐walled conidia. Although the infection process during the booting stage is well studied, its infection route before this is unclear. It was hypothesized that the thick‐walled conidia in soil penetrate rice roots, and the fungus latently colonizes roots and tiller buds at the vegetative stage. This hypothesis was tested using species‐specific detection methods. First, real‐time PCR with species‐specific primers and probe was used to estimate thick‐walled conidial number in the paddy field soil. Secondly, nested PCR with species‐specific primers showed that fungal DNA was detected in roots and shoot apices of rice plants in the vegetative stage. Thirdly, colourimetric in situ hybridization with a species‐specific oligonucleotide probe targeting 18S rRNA suggested that sparse mycelia or tightly condensed mycelia were present on the external surface of tiller buds enveloped by juvenile leaf sheaths at the vegetative stage. Thin hyphae were found around leaf axils at the surface of elongated stems at the heading stage, and the fungal hyphae grew in the rice root tissues. In addition, it was demonstrated that eGFP‐tagged transformants of the fungus invaded rice roots and colonized the surface of roots and leaf sheaths under artificial conditions. 相似文献
194.
Mizue Tsuji Kouki Ohta Kouta Tanaka Yuichi Takikawa 《Journal of General Plant Pathology》2017,83(3):152-161
Olive knot disease in Japan was first reported in Shizuoka Prefecture in 2014, and the causal agent was identified as Pseudomonas savastanoi pv. savastanoi. Subsequently, olive trees having knots were also found in Aichi and Kanagawa Prefectures in 2015, and the isolates from knots were also suspected to be P. savastanoi pv. savastanoi through preliminary examinations. Therefore, the Aichi and Kanagawa isolates were identified through comparison of isolates from three prefectures. Phylogenic analysis based on 16S rDNA and housekeeping genes (gyrB, rpoD, gltA and gap1) revealed that the isolates belonged to the same cluster as the pathotype strain, ICMP4352PT. The iaaM, H and L genes, which are involved in promotion of symptoms, and the ina gene coding the ice nucleation protein, were detected by PCR from all the isolates. In rep-PCR (ERIC and REP) analyses, the isolates yielded DNA fragment-banding patterns that were nearly identical to that of ICMP4352PT, but slight variations in banding patterns were observed among them. In a pathogenicity test, the isolates formed distinct knots on olive and pink jasmine. Phenotypic properties of the isolates were almost identical to those of ICMP4352PT, with the exception of d-sorbitol utilization. Consequently, Aichi and Kanagawa isolates from olive were identified as P. savastanoi pv. savastanoi, and several genetic diversities in terms of rep-PCR were found in the Japanese population of P. savastanoi pv. savastanoi, indicating their heterogeneity. 相似文献
195.
Washout Ratio in the Hepatic Vein Measured by Contrast‐Enhanced Ultrasonography to Distinguish Between Inflammatory and Noninflammatory Hepatic Disorders in Dogs 下载免费PDF全文
196.
The effects of microtopographical characteristics of the thick accumulation of ash and pumice, which were produced from 1977–78 eruptions, on seedling emergence and survival were monitored on the volcano Usu, northern Japan, 10 years after the eruptions. The characteristics included microtopography, texture of volcanic deposits on ground surface, volcanic‐deposit movements, water content on ground surface and chemical nature of volcanic deposits (ignition loss, P, K and pH). Polygonum sachalinense showed a higher seed germination percentage on finer‐particle ground surface under lab conditions, and Petasites japonicus var. giganteus germinated well on the ground surface with any particle sizes. However, in the field, the seedling densities of those two species and Anaphalis margaritacea var. angustior (three dominant species in this region) were higher on the sites with coarse particles and/or the rill inside the crater basin. The seedling germination timing and space overlapped among these species in the field. Those facts suggested that the seedling colonisation pattern was influenced more by the topographical characteristics of ground surface rather than the germination abilities. The amount of organic matter in the volcanic deposits was very low, even 11 years after the eruptions, and was not related to microtopography, suggesting that the effects of organic matter on seedling emergence did not differ along microtopographical characteristics. Inside of rills, higher water content seemed to be more advantageous for seed germination of those species. Volcanic deposits were physically stable in summer, but were heavily eroded after winter due to snowmelt. Most seedlings did not overwinter in the inside of rills with pumice where the volcanic deposits eroded intensively, indicating that the patterns of land degradation by melting snow should be mentioned carefully even with narrow scale. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
197.
Osawa T Morishige D Ohta D Kimura Y Miyake Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(4):459-464
To investigate the viability of timed artificial insemination (TAI) protocols in grazing Japanese Black cattle with long open period, ovarian status and progesterone and estradiol-17 beta profiles of the animals during the protocol were monitored. In 1998, prosta-glandin F(2a) (PG) was administered to 36 animals seven days after GnRH injection. Three out of the 36 animals were inseminated after detection of estrus and did not receive further treatment. The second GnRH was injected to the remaining 33 animals 48 hr after the PG injection and TAI was performed 24 hr later. In 1999, PG was injected to 25 animals six days after GnRH, the second GnRH was injected to 22 animals 48 hr after PG, and TAI was performed 16 hr later (The other three animals were inseminated before the time of TAI). The percentage of the animals with at least one functional corpus luteum and one follicle equal to or greater than 10 mm in diameter at PG injection was similar between the groups in 1998 and 1999. Likewise, the hormonal profiles were similar between the two groups. Pregnancy rates (PR) after the TAI protocols and natural mating in 1998 and 1999 were 75.0% and 88.0%, respectively. These figures were comparable to the PR obtained by conventional estrus synchronization protocols using PG (in 1995; 69.4%) or CIDR (in 1996; 59.1%). In conclusion, the TAI protocol can be applicable into grazing Japanese Black cattle with long open period. 相似文献
198.
OBJECTIVE: To characterize the expression and distribution of the Kit receptor in bovine bone marrow cells (BMC) and to define the function of its ligand, stem cell factor (SCF). ANIMALS: Six 7- to 70-day-old healthy male Holstein-Friesian calves. PROCEDURES: Expression and distribution of the Kit receptor were assessed by use of flow cytometry with monoclonal antibodies (mAb) against the bovine Kit protein. Using Giemsa-stained centrifuged preparations, the histologic appearance of Kit receptor positive (Kit+) BMC were evaluated. Semisolid cultures supplemented with granulocyte colony-stimulating factor (G-CSF) and SCF were used to measure the colony formation capacity of Kit+ BMC. RESULTS: The Kit receptor was expressed on approximately 18% of total BMC. Most of Kit+ BMC did not coexpress lineage markers, but a small subset of this population did coexpress CD3. The Kit+CD3- BMC were a heterogeneous cell population comprising blast-like cells such as myeloblasts, promyelocytes, rubriblasts, and prorubricytes. Conversely, Kit+CD3+ BMC had a lymphocyte-like appearance. Kit+ BMC formed colonies in semisolid culture with G-CSF, whereas Kit- BMC failed to grow. Addition of SCF to G-CSF resulted in superadditive enhancement in colony numbers and size. CONCLUSIONS: The Kit receptor is expressed primarily on immature blood cells in bovine bone marrow, and Kit+ BMC contain hematopoietic progenitor cells that are reactive to G-CSF. In addition, SCF synergizes with G-CSF to stimulate colony formation by these cells. Our results suggest that the Kit receptor and its ligand, SCF, are involved in early stages of granulopoiesis in calves. 相似文献
199.
Atopic NC/Nga mice as a model for allergic asthma: severe allergic responses by single intranasal challenge with protein antigen 总被引:1,自引:0,他引:1
Iwasaki T Tanaka A Itakura A Yamashita N Ohta K Matsuda H Onuma M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):413-419
Since certain characters of allergic asthma are common with other allergic disorders like atopic dermatitis, the possible relationship in etiology is expected. Herein, we investigated whether NC/Nga mice, an inherent animal model for human atopic dermatitis, are inclined to allergic asthma. A single intranasal challenge of NC/Nga mice immunized with ovalbumin (OVA) resulted in an increase in plasma levels of OVA-specific IgE, and typical pathological aspects of allergic asthma characterized by infiltration of numerous eosinophils, mucus hyper production of bronchial epithelial cells. Moreover, airway hyperresponsiveness to inhaled acetylcholine and marked enhancement of airway resistance after the challenge were observed as compared to control BALB/c mice. Delayed expression of mRNA of eosinophil active chemokines, interleukin-5, eotaxin, macrophage inflammatory protein-1alpha in concert with eosinophilia was determined in the lung of NC/Nga mice. These results suggest that asthmatic responses developed in NC/Nga mice challenged with OVA are very similar to human allergic asthma, and that NC/Nga mice are a useful model to elucidate various aspects of allergic asthma. 相似文献
200.
Kai K Komine Y Komine K Asai K Kuroishi T Kozutsumi T Itagaki M Ohta M Kumagai K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(10):873-878
To evaluate the clinical effects of bovine lactoferrin on staphylococcal mastitis in Holstein cows during the early non-lactating period, 41 mammary quarters were selected randomly from 36 cows on 3 dairy farms. Twelve quarters were infused intramammarily with bovine lactoferrin. Twenty-nine quarters were infused with antibiotic as a control. In the bovine lactoferrin-infused group, 91.7% of mastitic quarters were cured at 7 days after calving, compared with 48.3% in the control group. Furthermore, the changes in mammary secretion induced by the infusion of bovine lactoferrin were investigated. Mean numbers of staphylococci in mammary gland secretions were significantly decreased in both 5 bovine lactoferrin-infused quarters and 5 antibiotic-infused control quarters (p<0.05). Unlike in the control quarters, the mean total cell concentration in the mammary gland secretions increased in bovine lactoferrin-infused quarters. Similar results were obtained in 6 healthy quarters which were infused with bovine lactoferrin. In these quarters, the cell population contained mainly phagocytes such as polymorphonuclear leukocytes and cells positive for CD11b which is known as a complement receptor. The mean concentration of C3 in mammary gland secretions was significantly increased in 5 mastitic quarters infused with bovine lactoferrin (p<0.05), but showed no significant change in 5 mastitic control quarters. These results suggested that bovine lactoferrin treatment for staphylococcal mastitis in the early non-lactating period might increase the rate of cure through the induction of innate immunity in the host. 相似文献