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21.
Yusuke Kudo Kosuke Noborio Naoto Shimoozono Ryuki Kurihara Hayato Minami 《Paddy and Water Environment》2017,15(1):217-220
Many papers on measurements of greenhouse gases (GHGs) emission in rice paddies during a rice cropping season have been published. During a non-cropping season between Nov. and Apr., we investigated direct and indirect GHGs emissions in rice paddies. The indirect GHGs emission was evaluated as the amount of dissolved gases leaching from the paddy fields. Water management practices for the experiment were (1) continuous flooding (CF) and (2) non-flooding (NF). Although the direct CO2 emission in the CF treatment was remained nearly zero during the non-cropping period, direct CO2 emission in the NF treatment was continuously observed throughout the non-cropping period. The concentration of dissolved N2O in the NF treatment was below the detection limit of the instrument during the non-cropping period except immediately after the flooding and before the drainage. The concentration of dissolved N2O kept approximately 2 µg L?1 during the non-cropping period in the CF treatment. The direct CH4 emission and dissolved CH4 were not observed during the non-cropping period. Total gas emission in the NF treatment was 10 times as large as that in the CF treatment. Direct CO2 emission accounted for more than 90 % of the total emission in both treatments. 相似文献
22.
Nomura N Sakoda Y Soda K Okamatsu M Kida H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(4):441-447
H9N2 influenza viruses circulate in wild birds and poultry in Eurasian countries, and have been isolated from pigs and humans in China. H9N2 viruses isolated from birds, pigs and humans have been classified into three sublineages based on antigenic and genetic features. Chicken antisera to H9N2 viruses of the Korean sublineage reacted with viruses of different sublineages by the hemagglutination-inhibition test. A test vaccine prepared from a non-pathogenic A/duck/Hokkaido/49/1998 (H9N2) strain of the Korean sublineage, obtained from our influenza virus library, induced immunity in mice to reduce the impact of disease caused by the challenge with A/Hong Kong/1073/1999 (H9N2), which is of a different sublineage. The present results indicate that an inactivated whole virus vaccine prepared from a non-pathogenic influenza virus from the library could be used as an emergency vaccine during the early stage of a pandemic caused by H9N2 infection. 相似文献
23.
Hirao Y Shimizu M Iga K Takenouchi N 《The Journal of reproduction and development》2012,58(2):204-211
The oxygen environment in cell culture has a significant impact on the health and performance of cells. Here, we compared the effects of reduced (5%) and ambient (20%) oxygen concentrations on bovine oocyte-granulosa cell complexes, each containing a growing oocyte 90-102 μm in diameter, cultured for 14 days. Both oxygen concentrations showed some advantages and disadvantages; in 5% oxygen, the survival rate of oocytes was significantly higher than in 20% oxygen, but the resulting oocytes were significantly smaller, which was a serious disadvantage. During the first 4 days of culture, the growth and viability of oocytes were satisfactory using 5% oxygen. This observation led us to examine the effect of changing the oxygen concentration from 5% to 20% on Day 4 in order to minimize the expected disadvantages of constant 5% and 20% oxygen. The largest population of fully grown oocytes was obtained from cultures in which the oxygen concentration was changed in this way, which also led to higher oocyte viability than in constant 20% oxygen. A similar tendency was found in the frequency of oocytes becoming blastocysts after in vitro fertilization. Surviving oocytes eventually became located within an enlarged dome-like structure, and although the 5% oxygen environment may have been appropriate for oocyte growth in the early stages, 20% oxygen may have been necessary for the growth of oocytes in the dome-like structure. These results indicate an effective way of modulating oxygen concentration according to the growth of oocyte-granulosa cell complexes in vitro. 相似文献
24.
In mammalian embryo culture, the embryo:medium volume ratio can substantially affect embryo developmental performance. In the present study, we tested the possibility of improving the growth of bovine oocytes by reducing the medium volume, from a typical volume used in mouse follicle culture to a minimum possible level. A total of 282 complexes, each containing a growing oocyte 87-100 mum in diameter, were individually placed in microdrops of 2, 5, 10 or 20 microl and cultured for 13 days in a modified TCM-199 supplemented with 4% polyvinylpyrrolidone (molecular weight: 360 kDa). Oocyte diameter was measured every other day to trace the growth of each oocyte. Half the medium was replaced every other day or every day, and comparison revealed that daily replacement was more favorable for culture of these microdrops. The highest survival rate, 95%, occurred in the 20-microl microdrops, where most oocytes continued to grow throughout the culture period. In comparison, in the 5- and 10-microl microdrops, more oocytes died, and growth slowed towards the end of culture. In the 2-microl microdrops, which had the highest death rate, growth virtually ceased after 9 days. The surviving oocytes were usually accompanied by a characteristic dome-like structure of the granulosa cell mass, except in the 2-microl microdrops. In conclusion, the 20-microl microdrops allowed oocyte growth at an acceptable level, and any further reduction of the volume only had a negative impact on oocytes. 相似文献
25.
Kitai S Shimizu A Kawano J Sato E Nakano C Kitagawa H Fujio K Matsumura K Yasuda R Inamoto T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(3):269-274
A total of 444 samples of raw chicken meat (thighs, breasts, wings, livers, gizzards, hearts and ovaries) that retailed at 145 different supermarkets in 47 prefectures in Japan were examined for contamination with Staphylococcus aureus in association with its enterotoxigenicity. S. aureus was isolated from 292 (65.8%) of the samples, and from 131 of the 145 supermarkets. There was no significant difference in the detection rate of S. aureus according to the type of meat examined. About 80% of 714 isolates belonged to the poultry (57.1%) and human biotypes (22.1%). Seventy-eight (21.7%) of 360 isolates were enterotoxigenic and isolated from 78 samples in 53 supermarkets in 31 prefectures. Staphylococcal enterotoxins (SEs) produced were SEB (50 isolates), SEA (14), SEC (8), SED (2), SEA+SEB (2), and SEA+SEC (2). Most of the enterotoxigenic isolates belonged to the human and poultry biotypes, coagulase type VII, VIII or IV, and were lysed by phages of group III. Identical SE types, biotypes, coagulase types and pulsed-field gel electrophoresis (PFGE) patterns were shown in isolates from different types of meat at the same supermarket and from samples taken from different supermarkets in the same prefectures or in isolates from samples obtained from several different prefectures. Among the 50 SEB-producing isolates, 27 yielded three similar PFGE patterns that differed by only a few fragments, suggesting that they were closely related genetically. The three patterns were found in isolates of samples that retailed at 17 supermarkets in 11 prefectures, indicating that they may be disseminated among raw chicken meat in Japan. 相似文献
26.
Okada K Nakae N Kuramochi K Yin SA Ikeda M Takami S Hirata T Goryo M Numakunai S Takeshima SN Takahashi M Tajima S Konnai S Onuma M Aida Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(12):1231-1235
Sheep were inoculated with high tax coded pBLV-IF (H group, Nos.1-5) of bovine leukemia virus (BLV), wild tax coded pBLV-IF (W group, Nos. 6-11), or control plasmid (C group, Nos. 12-14). During the observation period (4 to 46 months), 5 of 5 cases in H group and 3 of 6 cases (Nos. 6, 7, 9) in W group became positive for gp 51. Only 1 case in H group became leukemic, and one case each of H and W groups developed lymphoma. In No. 3, lesions were found in multiple organs including the lymph nodes, gastrointestinal tract following abomasum, and heart. In No. 6, lesions of lymphoma were found only in the jejunum and heart. Morphologically, small to middle-sized lymphocytic neoplastic (NP) cells were found in both cases, but lymphoblastic NP cells were found only in No. 3. By immunohistochemical examination, the phenotypes of NP cells were determined as CD1-, CD4-, CD5- -, CD8alpha-, sIgM+, lambda light chain+, B-B4+, MHC class II+ in both case. The results of this study indicate that inoculation of pBLV-IF can induce lymphocytic and lymphoblastic leukemia/lymphoma in sheep. Additionally, it is suggested that the expression rate of tax gene is not associated with the development of leukemia/lymphoma in sheep experimentally inoculated with pBLV-IF. 相似文献
27.
Takahashi H Inumaru S Takahashi M Watanabe S Iga K Yokomizo Y Geshi M Okano A Okuda K 《The Journal of reproduction and development》2003,49(6):433-440
Bovine interferon (bIFN) tau, which plays a key role in maternal-fetal recognition of pregnancy, was expressed by an Autographa californica nuclear polyhedrosis virus expression system. cDNA coding bIFNtau was derived from cultured trophoblast cells. The recombinant (r) bIFNtau had high antiviral activity (1 x 10 (8) IU/mg) and the molecular weight of rbIFNtau was estimated to be 23 kDa by Western blotting analysis. We investigated the biological effect of rbIFNtau on prostaglandin (PG) F(2alpha) synthesis in cultured bovine endometrial epithelial cells in the presence or absence of oxytocin (OT, 100 nM). rbIFNtau suppressed basal and OT-induced PGF(2alpha) production in a dose-dependent manner (1-1,000 ng/ml). These results showed that biologically active rbIFNtau was produced in the baculovirus expression system, and that rbIFNtau had the ability to suppress the synthesis of PGF(2alpha) from bovine endometrial epithelial cells. 相似文献
28.
Murakami S Shibaya M Takeuchi K Skarzynski DJ Okuda K 《The Journal of reproduction and development》2003,49(6):531-538
To establish a storage system for isolated endometrial cells, we investigated the basal, oxytocin (OT)- and tumor necrosis factor (TNF) alpha-stimulated production of prostaglandin (PG) F(2alpha) in bovine-passaged and frozen-thawed endometrial cells. Stromal and epithelial cells obtained from cows in the early stage of the estrous cycle (Days 2-5) were frozen at -80 C or further cultured and/or passaged until passage 4 in DMEM/Ham's F-12 supplemented with 10% calf serum. A fresh-unfrozen primary culture and one-time passaged fresh-unfrozen cells were used as the control. When both unfrozen and frozen cells reached confluence, the culture medium was replaced with fresh medium with 0.1% BSA and the cells were stimulated with OT (100 ng/ml) or TNFalpha (1 ng/ml) for 4 h. The passage and freezing of the endometrial cells did not affect their morphology. In primary culture of frozen and unfrozen endometrial cells, OT strongly stimulated PGF(2alpha) production in epithelial cells, and TNFalpha strongly stimulated PGF(2alpha) production in stromal cells (P<0.05). The basal output of PGF(2alpha) in frozen stromal cells was similar to that in unfrozen stromal cells. However, the basal output of PGF(2alpha) in frozen epithelial cells was significantly lower than that unfrozen cells (P<0.05). On the other hand, in passaged cells, the basal level of PGF(2alpha) production was retained until passage 1 in epithelial cells, whereas it was retained until passage 4 in stromal cells. Although epithelial cells responded to OT in PGF(2alpha) production until passage 2 (P<0.05), the stromal cells showed a significant response to TNFalpha until passage 4 (P<0.05). These results suggest that stored cells could be used for studying the physiology of bovine endometrium in vitro until passage 1 in endometrial epithelial cells, and until passage 4 in stromal cells. 相似文献
29.
Kuwano A Katayama Y Kasashima Y Okada K Reilly JD 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(10):893-900
In horses with chronic laminitis, an abnormal horny structure called lamellar wedge, is generated between the hoof wall and the laminar epidermis. To be able to manage horses with chronic laminitis correctly, more information about the pathological state of this abnormal horn is required. The aim of this study was to collect and analyze objective morphological data about the abnormal horn in order to understand its morphology and development. In the study, the abnormal horn was grossly visible on the sagittal hoof section from approximately 20 days after the onset of disease. In the histological observations, the structural characteristics of this abnormal horn were similar to the white line tissue, suggesting it is an ectopic white line. Mean value of the cross-sectional area of the abnormal horn against the distal phalanx section area (A/D) was 0.29 cm(2) SD +/- 0.14 and it finally showed an eight-fold increase over the mean value of normal white line section area against the distal phalanx section area. In conclusion, a large amount of the ectopic white line is thought to be finally able to inhibit normal hoof wall growth, so that it should be resected at the optimum time when would be after one month from the onset of the disease. 相似文献
30.
Leok CS Inoue I Sato T Haritani M Tanimura N Okada K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(12):1129-1131
Prosthogonimus ovatus infection was detected in 5 of 130 chickens in the oviduct and 4 chickens in the bursa of Fabricius. Scanning electron microscopy (SEM) revealed that the spines of the P. ovatus were densely distributed on the cuticula of the entire dorsal surface of body, but on the ventral surface, they were densely present to the level of ventral sucker but gradually decreased in density posteriorly, and they could not be seen in the posterior 1/3 area. The spines were finger-shaped and denticulate at the tip. Histopathological examination showed that polypous elevations, degeneration and exfoliation of the mucosal epithelium were detected in the bursa of Fabricius possibly by the suction of flukes, in addition to the stratification of the mucosal epithelium, and interstitial cell infiltration. 相似文献