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1.
2.
Denitrification is an important part of the nitrogen cycle in the environment, and diverse bacteria, archaea, and fungi are known to have denitrifying ability. Rice paddy field soils have been known to have strong denitrifying activity, but the microbes responsible for denitrification in rice paddy field soils are not well known. Present study analyzed the diversity and quantity of the nitrite reductase genes (nirS and nirK) in a rice paddy field soil, sampled four times in one rice-growing season. Clone library analyses suggested that the denitrifier community composition varied over sampling time. Although many clones were distantly related to the known NirS or NirK, some clones were related to the NirS from Burkholderiales and Rhodocyclales bacteria, and some were related to the NirK from Rhizobiales bacteria. These denitrifiers may play an important role in denitrification in the rice paddy field soil. The quantitative PCR results showed that nirK was more abundant than nirS in all soil samples, but the nirK/nirS ratio decreased after water logging. These results suggest that both diversity and quantity changed over time in the rice paddy field soil, in response to the soil condition.  相似文献   
3.
Severe adverse reactions in cats after vaccination were examined from 316 cases reported to the Ministry of Agriculture, Forestry and Fisheries (MAFF) in Japan during 15-year period from April 2004 to March 2019. We found that 130 (41%) showed anaphylaxis, and 99 (76%) of the 130 cases of anaphylaxis resulted in death. Veterinarians should be well prepared to deal with vaccine-associated anaphylaxis in cats. Bovine serum albumin (BSA) as indicator of purification was detected at high levels in commercially available feline vaccines. BSA might derive from fetal calf serum in culture media. This study provides useful information about anaphylaxis including critical details of the potential clinical signs associated with adverse events to feline vaccination.  相似文献   
4.
Variability in catch-per-unit-effort (CPUE) was examined for the autumn cohort of Ommastrephes bartramii collected with research driftnets during 1979–1998 along five longitudinal transects passing through the Subarctic, Transitional and Subtropical Domains in the North Pacific. CPUE was generally low during the period of intensive commercial driftnet fishing (1980–1992) and increased following the 1992 moratorium on the use of large-scale driftnets. However, CPUE levels were low for the cohorts hatched in 1992 and 1996 (captured in subsequent years owing to a one-year life of O. bartramii ) that experienced low sea surface temperatures from hatching to recruitment. Among similar-aged squid collected from 180° and 179°30'W in June, mantle lengths were significantly greater in 1997 than during 1995–96. These findings suggest that the driftnet fishery and sea surface temperatures from hatching to recruitment strongly affected stock abundance and possibly growth.  相似文献   
5.
The ELISA we developed was able to determine the antigen content and was suitable for a potency test, and we described a relative potency assay method which determines the potency of test vaccines by comparing the ELISA value of a test vaccine to that of a reference vaccine. In the present study, we standardized the reference vaccine used for determining the potencies of test vaccines, and established a potency test by ELISA. We evaluated the proposed reference vaccine by the neutralizing antibody responses in dogs after vaccination, by the challenge protection test in guinea pigs (GP potency test), which is the earlier official potency test used in Japan, and by the NIH potency test, which is widely used throughout the world. The results showed that a 4-fold dilution of the proposed reference vaccine induced sufficient immunity in dogs. A 3-fold dilution of the proposed reference vaccine passed the GP potency test. The international units (IU) calibrated by the NIH potency test were 3.7 IU/dose. From the results and the WHO recommendation that veterinary rabies vaccines should have a potency of at least 1.0 IU/dose, we determined to dilute the proposed reference vaccine by 3 fold and regarded it as the reference vaccine. Finally, we confirmed that there is a good agreement between the results of the potency test by ELISA and the results of the GP potency test. The establishment of the potency test by ELISA has made it possible to monitor the potency in the production process and has contributed to the stable production of the vaccine.  相似文献   
6.
Wild rodents (58 Apodemus speciosus, 29 A. argenteus and 7 Microtus montebelli) were surveyed for endoparasites in Iwate Prefecture, Japan, from October to December 1995 and from April to October 1996. Two trematodes (Echinostoma macrorchis, Plagiorchis muris), 4 or more cestodes (Hymenolepis diminuta, Raillietina coreensis, Cladothyridium spp., Cysticercus fasciolaris), 12 nematodes (Carolinensis minutus, Eucoleus sp., Heligmosomoides kurilensis, H. protobullosus, H. speciosus, Heterakis spumosa, Rhabditis (Pelodera) orbitalis, Rictularia cristata, Syphacia emileromani, S. frederici, S. montana, Trichuris sp.) and 3 protozoans (Giardia sp., Trichomonas sp., Trypanosoma sp.) were identified. The two species of Apodemus were similar to each other, but they were extremely different from M. montebelli in parasite fauna.  相似文献   
7.
Abstract This study describes 26 cats with mosquito bite hypersensitivity. Most were short-haired, free-roaming cats. Typical clinical features were seasonal (summer), symmetric miliary dermatitis on the pinnae. Mosquito bite exposure with Aedes albopictus was performed on the pinnae and the lateral thorax in five cases and three healthy cats. All sites showed weals within 20 min. Papules, which revealed eosinophilic dermatitis, were recognized during a 12–48-h period. The control cats showed only slight and transient erythema after being bitten. Intradermal skin tests with an extract of A. albopictus were performed in three cases, and Prausnitz-Küstner tests under A. albopictus bites were performed in three cases. Both tests showed weals in all cases studied, although papules were not observed. Intradermal skin tests with the control cats, and Prausnitz-Küstner tests with saline and healthy cat serum failed to produce any positive reactions. The findings indicate that mosquito bite hypersensitivity in cats is triggered by a type I hypersensitivity reaction to mosquito antigens. Certain other factors may be involved in the formation of delayed papular reactions. Whether this is a normal or abnormal reaction to mosquito bites is also discussed. Résumé— Cette étude a été réalisée sur 26 chats atteints d'hypersensibilité aux piqûres de moustiques. La plupart des chats sont des chats à poils courts vivant à l'extérieur. Les lésions cliniques sont caractérisées par une dermatite miliaire symétrique sur les pavilions auriculaires survenant l'été. Une exposition aux piqûres de moustique (Aedes albopictus) a été réalisée sur les pavilions auriculaires et sur la face latérale du thorax de 5 chats atteints et de 3 chats sains. Tous les sites d'exposition montrent des reactions à 20 minutes. Ces papules qui traduisent une dermite éosinophilique, persistent pendant 12 à 48 heures. Les chats sains ne montrent qu'un érythème transitoire après la piqûre, des tests d'intradermoréaction avec un extrait d'A. albopictus ont été réalisés dans 3 cas, des tests de Prausnitz-Küstner spécifiques dans 3 cas. Les deux tests montrent des reactions dans tous les cas étudiés bien que des papules ne soient pas observées. Ces tests réalisés sur les chats témoins, ne montrent aucune reaction, positive ou significative. Ces résultats suggèrent que l'hypersensibilité aux piqûres de moustiques chez le chat est regie par une hypersensibilité de type I à divers antigènes de moustique. D'autres facteurs doivent intervenir dans la formation des reactions papuleuses retardées. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Réactivité cutanée aux piqûres de moustiques et à leurs antigènes chez le chat.) Veterinary Dermatology 1997; 8 : 19–26.] Résumén Este estudio describe 26 gatos con hipersensibilidad a la picadura de mosquito. La mayoria eran gatos en régimen abierto de pelo corto. Las caracteristicas clinicas tipicas fueron dermatitis miliar simétrica estacional (verano) en pabellones auriculares. Se llevó a cabo una exposición a la picadura del mosquito Aedes albopictus en los pabellones y en el tórax lateral en 5 casos y 3 gatos sanos. Todas las zonas mostraron ronchas a los 20 minutos. Aparecieron pápulas con dermatitis eosinofilica a las 12 a 48 horas. Los gatos control mostraron solamente eritema leve y transitorio tras la picadura. Se realizaron pruebas cutáneas intradérmicas con extracto de A. albopictus en 3 casos y pruebas de Prausnitz-Küstner bajo picaduras de A. albopictus en 3 casos. Ambas pruebas mostraron ronchas en todos los casos estudíados, aunque no se observaron pápulas. Las pruebas intracutáneas con los gatos control y las pruebas de Prausnitz-Küstner con suero salino y suero de gatos sanos no causaron reacción positiva. Estos hallazgos indican que la hipersensibilidad a la picadura de mosquito se inicia por una hipersensibilidad de tipo I a antigenos del mosquito. Otros factores pueden estar implicados en la formación de reacciones papulares retardadas. Se discute si esta es una reacción normal o anormal a la picadura de mosquito. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Reactividad cutanea a las picaduras de mosquito y sus antigenos en el gato.) Veterinary Dermatology 1997; 8 : 19–26.] Zusammenfassung— Diese Studie beschreibt 26 Katzen mit Mückenstichhypersensibilität. Die meisten der Tiere waren kurzhaarig und hatten Freilauf. Die typischen klinischen Bilder bestanden in säsonaler (Sommer), symmetrischer miliarer Dermatitis an den Ohrmuschein. Es wurde eine Exposition auf Mückenstiche mit Aedes albopictus an den Ohrmischein und am lateralen Thorax bei 5 Patienten und 3 gesunden Katzen durchgeführt. Alle Stellen zeigten Quaddeln innerhalb von 20 Minuten. Papeln, die eine eosinophile Dermatitis enthüllten, wurden nach einer Zeitspanne von 12 bis 48 Stunden gesehen. Die Kontrollkatzen zeigten ein nur leichtes und transientes Erythem nach dem Biß. Intradermale Hauttests mit einem Extrakt von A. albopictus wurden in 3 Fallen durchgeführt und Prausnitz-Küstner-Tests unter A. albopictus-Bissen wurden in 3 Fallen durchgeführt. Beide Tests zeigten Quaddeln in alien untersuchten Fallen, obwohl Papeln nicht beobachtet wurden. In den intradermalen Hauttests bei den Kontrollkatzen und Prausnitz-Küstner-Tests mit Kochsalz-Lösung und Serum gesunder Katzen gelang es nicht, irgendweiche positiven Reaktionen zu erzeugen. Diese Befunde zeigen, daß Mückenstichhypersensibilität bei Katzen durch eine Typ 1-Hypersensibilitätsreaktion auf Mückenantigene ausgelöst wird. Bestimmte andere Faktoren können in die Bildung von verzögerten papulären Reaktionen miteinbezogen sein. Ob dies eine normale oder unnormale Reaktion auf Mückenstiche ist, wird ebenfalls diskutiert. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Hautreaktivität auf Mückenstiche und Antigene bei der Katze.) Veterinary Dermatology 1997; 8 : 19–26.]  相似文献   
8.
As a new use of bamboo, bamboo cubes may be useful as a shot-blast material for surface treatments. However, a suitable processing technique for bamboo cubes has not been established. In this study, to obtain basic knowledge regarding the processing technology for bamboo cubes, we installed shearing blades (upper and lower blades) in a universal testing machine to test cross-sectional shearing of bamboo. The shearing force generated in this shearing was composed of a vertical component (F v), a forward component (F f), and a side component (F s). This shearing force (F v, F f, and F s) and the machining accuracy were investigated under various processing conditions. The shearing force became larger as the thickness of bamboo increased. In particular, F v showed a tendency to increase rapidly. Changes in the shear angle of the upper blade had a remarkable influence on F v. This result suggests that the shearing force could be greatly decreased by adjusting the shear angle. The shearing force within bamboo of 3mm in thickness was almost unaffected by the blade angle, and the change of shearing force with increasing clearance was almost indiscernible. It was clearly demonstrated that a large number of bamboo cubes could be made when the shear angle was large and cross-sectional shearing was performed from the bark side. However, a consequence of a large shear angle is that burr area increases. Part of this article was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, March 2003  相似文献   
9.
Trunk rot, caused by Fomitiporia torreyae, is one of the most economically important sap rot diseases on Cryptomeria japonica, especially on a cutting cultivar ‘Sanbu-sugi’. This disease had been reported only from Chiba and Ibaraki prefectures in Japan; however, a similar trunk rot on Japanese cedars was found recently in Kyoto prefecture. We identified the causal agent of the trunk rot on Japanese cedars in Kyoto prefecture, clarified the genotype of ‘Sanbu-sugi’ (sensu stricto) using microsatellite markers, and then investigated the relatedness of these infected cedars with ‘Sanbu-sugi’. The pathogen was identified as F. torreyae by its DNA sequences and morphological characteristics of the fruiting body. The 25 ramets of ‘Sanbu-sugi’ had only one genotype based on eight microsatellite loci. Infected Japanese cedars in Kyoto were comprised of different genotypes and showed no close relatedness to ‘Sanbu-sugi’. This is the first report of trunk rot caused by F. torreyae on cultivars of Japanese cedar with no relatedness to ‘Sanbu-sugi’ outside of Chiba and Ibaraki prefectures and showed the potential for expansion of this disease to Japanese cedar plantations in other areas.  相似文献   
10.
Erythrocyte pyruvate kinase (PK) deficiency is an inherited glycolytic erythroenzymopathy caused by mutations of the PKLR gene. A causative mutation of the feline PKLR gene was originally identified in Abyssinian and Somali cats in the U.S.A. In the present study, a TaqMan probe-based real-time PCR genotyping assay was developed and evaluated for rapid genotyping and large-scale screening for this mutation. Furthermore, a genotyping survey was carried out in a population of four popular purebred cats in Japan to determine the current mutant allele frequency. The assay clearly displayed all genotypes of feline PK deficiency, indicating its suitability for large-scale survey as well as diagnosis. The survey demonstrated that the mutant allele frequency in Abyssinian and Somali cats was high enough to warrant measures to control and prevent the disease. The mutant allele frequency was relatively low in Bengal and American Shorthair cats; however, the testing should still be carried out to prevent the spread of the disease. In addition, PK deficiency should always be considered in the differential diagnosis of anemia in purebred cats in Japan as well as worldwide.  相似文献   
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