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81.
82.
Kahori Arita Kiyoshi Isowa Takashi Ishikawa Hideo Aoki Hiromi Ohta 《Fisheries Science》2012,78(3):625-630
The post-thaw motility and fertility of Japanese pearl oyster sperm show large variances, even among sperm samples obtained
from the same individuals. This study aimed to clarify the factors that cause such differences. Spermatozoa were diluted 50
times with diluent comprising 10 % methanol, 18 % fetal bovine serum, and 72 % seawater, and dispensed into 0.25 ml straws.
A total of 59 straws were cooled, one by one, at 11 different heights from the surface of liquid nitrogen (LN) to −50 °C,
and then immediately immersed in LN. After thawing the straws, the relationships between the cooling rate and the post-thaw
motility and post-thaw fertility of the spermatozoa were examined. Both the post-thaw motility and the post-thaw fertility
showed a sharp peak when the straws were cooled at around −20 °C/min. There was a strong correlation between post-thaw motility
and fertility (P < 0.001). There was a large difference in the cooling rates and the post-thaw motilities and fertilities of the spermatozoa,
even between straws cooled at the same height. These results indicate that the optimum range for the cooling rate of oyster
spermatozoa is quite narrow, and the method of cooling straws at a fixed distance from the LN surface is unsuitable for the
cryopreservation of Japanese pearl oyster spermatozoa. 相似文献
83.
Naoya Yamaguchi Takashi Sayama Hiroyuki Yamazaki Tomoaki Miyoshi Masao Ishimoto Hideyuki Funatsuki 《Breeding Science》2014,64(4):300-308
Lodging tolerance (LT) is an important trait for high yield and combine-harvesting efficiency in soybean [Glycine max (L.) Merr.]. Many previous studies have investigated quantitative trait loci (QTLs) for lodging score (LS) in soybean. Most of the investigated QTLs were located in the proximal region of maturity or growth habit loci. The aim of this study was to identify genetic factors for LT not associated with maturity or growth habit. QTL analysis was performed using a recombinant inbred line (RIL) population derived from a cross between ‘Toyoharuka’ (TH), a lodging-tolerant cultivar, and ‘Toyomusume’ (TM). The genotypes of TH and TM were estimated as both e1e2E3E4 and dt1. The average LS over 4 years was used for QTL analysis, identifying a major and stable QTL, qLS19-1, on chromosome 19. The LS of the near-isogenic line (NIL) with the TH allele at Sat_099, the nearest marker to qLS19-1, was significantly lower than the NIL with the TM allele at that position. The TH allele at Sat_099 rarely had a negative influence on seed yield or other agronomic traits in both NILs and the TM-backcrossed lines. Our results suggest that marker-assisted selection for qLS19-1 is effective for improving LT in breeding programs. 相似文献
84.
Kiyoshi Sakuragi Chiaki Hori Kiyohiko Igarashi Masahiro Samejima 《Journal of Wood Science》2018,64(6):845-853
Ammonia pretreatment is a promising technique for enhancing enzymatic saccharification of lignocellulosic biomass. However, an enzymatic cocktail suitable for the breakdown of pretreated biomass samples is still being developed. The basidiomycete Phanerochaete chrysosporium is a well-studied fungus with regard to bioconversion of lignocellulosic biomass. In the present work, we analyzed proteins secreted by P. chrysosporium grown on untreated and ammonia-treated birch wood meal. Fungal growth, xylanase activity, and extracellular protease activity increased in the media containing the ammonia-treated biomass; however, cellulase production decreased compared to that observed in the untreated biomass. Secreted extracellular proteins were separated by two-dimensional electrophoresis and identified by liquid chromatography ion–trap mass spectrometry. Fifty-five spots corresponding to secreted proteins were chosen for further analysis. In the culture with ammonia-treated biomass, the relative concentration of a xylanase belonging to glycoside hydrolase (GH) family 11 increased, while acetyl xylan esterases belonging to carbohydrate esterase family 1 decreased. Moreover, GH family 10 xylanases were promoted proteolysis in the culture of ammonia-treated biomass, leading to the loss of family 1 carbohydrate-binding modules. These results indicated that P. chrysosporium produced enzymes related to the recognition of structural changes on xylan with de-acetylation and introduction of nitrogen by ammonia pretreatment of birch wood meal. 相似文献
85.
86.
Tropical Animal Health and Production - We evaluated the relationship between the temperature–humidity index (THI) and health and growth performance in Japanese black calves in Japan. Data... 相似文献
87.
An experiment is made to detect the land-cover change in the area located to the south of Aksu in the northern Taklimakan desert through analyses of satellite data pixel by pixel basis. The analyzed data are those observed in the late summer and early autumn of 1973, 1977, 1993 and 1995. As a parameter of land-cover, SAVI (Soil Adjusted Vegetation Index) derived from the data of Landsat MSS and JERS-1 OPS (Optical Sensor) is used. The result indicates the increase of vegetation in the oasis areas, confluent area of the Yarkant and Kashgar Rivers and around reservoirs while little change occurs in the desert area. The 1973 satellite image shows the abundant flow in the Yarkant River while the river is almost dried up in the satellite images of later years. The trend of the decrease in the Hotan River flow is recognized although not so dramatic as that of the Yarkant River. 相似文献
88.
The uncertainty in pesticide residue levels (UPRL) associated with sampling size was estimated using individual acetamiprid and cypermethrin residue data from preharvested apple, broccoli, cabbage, grape, and sweet pepper samples. The relative standard deviation from the mean of each sampling size (n = 2(x), where x = 1-6) of randomly selected samples was defined as the UPRL for each sampling size. The estimated UPRLs, which were calculated on the basis of the regulatory sampling size recommended by the OECD Guidelines on Crop Field Trials (weights from 1 to 5 kg, and commodity unit numbers from 12 to 24), ranged from 2.1% for cypermethrin in sweet peppers to 14.6% for cypermethrin in cabbage samples. The percentages of commodity exceeding the maximum residue limits (MRLs) specified by the Japanese Food Sanitation Law may be predicted from the equation derived from this study, which was based on samples of various size ranges with mean residue levels below the MRL. The estimated UPRLs have confirmed that sufficient sampling weight and numbers are required for analysis and/or re-examination of subsamples to provide accurate values of pesticide residue levels for the enforcement of MRLs. The equation derived from the present study would aid the estimation of more accurate residue levels even from small sampling sizes. 相似文献
89.
Uno Y Matsuno K Nakamura C Utoh M Yamazaki H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):487-490
Cytochrome P450 (CYP) is important for metabolism of not only xenobiotics such as drugs, but also endogenous compounds including arachidonic acids. CYP4A11, CYP4F3v2, CYP4F11, and CYP4F45 have been identified in cynomolgus macaque, an animal species widely used for investigation of drug metabolism due to its evolutionary closeness to human. However, their metabolic functions have not been investigated. In this study, proteins were heterologously expressed in Escherichia coli and characterized by metabolic assays using arachidonic acids as substrates that are metabolized by CYP4 isoforms in human. The results showed that all four CYPs metabolized arachidonic acids. Therefore, cynomolgus macaque CYP4A11, CYP4F3v2, CYP4F11, and CYP4F45 are functional enzymes. 相似文献
90.
Hashimoto S Yamazaki K Obi T Takase K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(3):293-297
The prevalence of footpad dermatitis (FPD) in broiler chickens in Japan was investigated. In the first examination at slaughterhouses, lesions were commonly observed on the footpads of a total of 8,985 broiler chickens from 45 flocks on 36 farms. In 3 flocks, all the birds examined had lesions. In the other 42 flocks, the incidence of FPD ranged from 31.9% (81/254) to 99.5% (1/222). The footpad lesions were classified into 4 categories according to the severity of dermatitis as follows; score 0, 1,181 birds (13.1%); score 1, 2,992 birds (33.3%); score 2, 3,000 birds (33.4%); and score 3, 1,812 birds (20.2%). The mean scores of the flocks varied widely from 0.31 to 2.69. Males had higher mean scores than females. No significant differences were found between the mean scores of birds reared in windowless houses and those in open-sided houses. On 4 farms, the investigation was carried out in different seasons, and 3 of them showed higher mean scores in winter than in summer. Next, observation of 2,255 birds from 15 flocks on 5 farms during a 4-week rearing period revealed that FPD was already produced at 7 days of age and worsened with age. 相似文献