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排序方式: 共有213条查询结果,搜索用时 15 毫秒
131.
Yoshinobu UEMOTO Takashi KIKUCHI Hikaru NAKANO Shuji SATO Tomoya SHIBATA Hiroshi KADOWAKI Kazuo KATOH Eiji KOBAYASHI Keiichi SUZUKI 《Animal Science Journal》2012,83(5):375-385
The leptin receptor (LEPR) gene is considered a candidate gene for fatness traits. It is located on SSC 6 in a region in which quantitative trait loci (QTLs) for backfat thickness (BF), fat area ratios, and serum leptin concentration (LEPC) have previously been detected in a Duroc purebred population. The objectives of the present study were to identify porcine LEPR polymorphisms and examine the effects of LEPR polymorphisms on fatness traits in this same population. The Duroc pigs (226 to 953 pigs) were evaluated for BF, fat area ratios using image analysis, and LEPC. A total of seven single nucleotide polymorphisms (SNPs) in the full‐length LEPR coding region were identified in pigs from the base population. Four non‐synonymous SNPs of the LEPR gene and 15 microsatellite markers on SSC 6 were then genotyped in all pigs. During candidate gene analysis, we detected significant effects of the non‐synonymous SNP c.2002C>T in exon 14 on all traits. In fine mapping analysis, significant QTLs for BF, fat area ratios, and LEPC were detected near the LEPR gene in the same region. These results indicated that the c.2002C>T SNP of LEPR has a strong effect on BF, fat area ratios and LEPC. 相似文献
132.
Tetsushi ONO Keiichi HISAEDA Yoichi INOUE Yutaka YAMADA Kenichi SHIBANO Ikki MITSUI Chizuka HENMI Yumi UNE Hideaki HAYASHI Sanggun ROH Masakatsu NOHARA Eiji UCHIDA Hajime NAGAHATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):220
This study reports findings from the pathological examination of the forestomach of an 11-month-old Japanese Black steer with severely retarded growth (41% of expected weight) and chronic ruminal tympany. The ruminal papillae were weakly formed (0.3–0.5 cm long) and unevenly distributed. The cellulae and cristae reticuli were underdeveloped; the cristae were 0.4–0.7 cm in height and milky white. The keratinized layer in the stratified squamous epithelium was thickened. Ruminal pH was 5.25, and ruminal volatile fatty acid concentration was 11.7 mM. The steer’s severely retarded growth was considered to be caused by malnutrition due to developmental and functional failure of the forestomach. 相似文献
133.
Ferulic acid (FA) and p-coumaric acid (CA) are absorbed by the monocarboxylic acid transporter (MCT) in Caco-2 cells, although gallic acid (GA) is not. Therefore, the MCT is selective for certain phenolic acids. Absorption of orally administered CA and GA in rats was studied to obtain serum pharmacokinetic profiles and to investigate their intestinal absorption characteristics in vivo. Rats were administered 100 micromol/kg body weight of CA and GA, and blood was collected from the portal vein and abdominal artery after administration. CA, GA, and their metabolites were quantified with a highly selective and sensitive coulometric detection method using high-performance liquid chromatography-electrochemical detection. Ingested CA was rapidly absorbed in the gastrointestinal tract in an intact form. The serum concentration of intact CA in the portal vein peaked 10 min after dosing (C(max) was 165.7 micromol/L). In contrast, GA was slowly absorbed, with a t(max) for intact GA of 60 min and a C(max) of 0.71 micromol/L. The area under the curve for intact CA and GA was calculated from the serum concentration profile in the portal vein to be 2991.3 and 42.6 micromol min L(-)(1), respectively. The relative bioavailability of CA against GA was about 70. This is the first demonstration that absorption efficiency of CA is much higher than that of GA in vivo. The absorption characteristics of CA are clearly different from those of GA. These findings are in good agreement with the results obtained in vitro using a Caco-2 cell system. 相似文献
134.
While studying water quality in the Tatara river, we realized that the river has various hydraulic and topographic characteristics
when flowing through different regions. Because of these specific characteristics, the application of the existing models
for simulation of its water quality may not be appropriate due to limitations in the models themselves. Therefore, we developed
a mathematical model that is suitable for short-term simulations of water quality in rivers with characteristics similar to
the Tatara river. The main foundation of the model is the one-dimensional transport equation established on the basis of the
mass conservation law. To solve this equation numerically, it was discretized by the method of finite-difference approximations,
and an algorithm has been programmed in Fortran 90. To verify the model, the Tatara river was chosen as a case study. Water
temperature, dissolved oxygen, hydraulic parameters in four typical blocks of the river, and meteorological data of the study
area, have been observed and used to test the model. By calibrating the model with different series of data collected from
the designated blocks, all results have shown a good fit between simulated data and the observed one. Therefore, the model
could be a reliable tool for simulating water quality in medium- and small-sized rivers over a short-term period. This research
has also indicated the changing tendencies of water temperature and dissolved oxygen in Tatara river in response to different
meteorological patterns over a daily 24-h period. Besides, the model could be improved to simulate other water quality variables,
which would be studied further. 相似文献
135.
Wu H Kanatous SB Thurmond FA Gallardo T Isotani E Bassel-Duby R Williams RS 《Science (New York, N.Y.)》2002,296(5566):349-352
Endurance exercise training promotes mitochondrial biogenesis in skeletal muscle and enhances muscle oxidative capacity, but the signaling mechanisms involved are poorly understood. To investigate this adaptive process, we generated transgenic mice that selectively express in skeletal muscle a constitutively active form of calcium/calmodulin-dependent protein kinase IV (CaMKIV*). Skeletal muscles from these mice showed augmented mitochondrial DNA replication and mitochondrial biogenesis, up-regulation of mitochondrial enzymes involved in fatty acid metabolism and electron transport, and reduced susceptibility to fatigue during repetitive contractions. CaMK induced expression of peroxisome proliferator-activated receptor gamma coactivator 1 (PGC-1), a master regulator of mitochondrial biogenesis in vivo, and activated the PGC-1 gene promoter in cultured myocytes. Thus, a calcium-regulated signaling pathway controls mitochondrial biogenesis in mammalian cells. 相似文献
136.
Autonomous navigation using global positioning system (GPS) or geomagnetic direction sensor (GDS) to detect absolute position is widely used. An alternative system that detects boundary lines and intersections information can be achieved using machine vision based navigation systems. The objectives of this research are the development of the intersection detection method using machine vision and the approaching/turning at the intersection using dead reckoning method. Intersection guidance markers (IGM) were installed on farm road intersections. The method of intersection recognition involved the search to detect the IGM instead of the actual intersection, which would be difficult because the latter changes appearance through the season. Hough Transform and coordinate transformation was used for this purpose. A dead reckoning system for approaching and turning on the intersection was developed. Rotary encoders installed on both sides of the crawler sprocket are used as guidance sensors. RTK-DGPS and fiber optic gyroscope (FOG) were used for evaluating the track of autonomous traveling. The result of field tests (the speed was 0.8 m/s) showed the rms of intersection detection error and the dead reckoning error were 0.12 m at 8.64 Hz processing speed and 0.063 m respectively. 相似文献
137.
138.
Liquefaction of beech wood in various supercritical alcohols 总被引:1,自引:0,他引:1
The liquefaction of Japanese beech (Fagus crenata Blume) was studied with various straight-chain alcohols in subcritical and supercritical states using a batch-type reaction
vessel to obtain liquid fuel from lignocellulosics. Under the reaction condition of 270°C, beech wood was liquefied to some
extent in all alcohols with about 50%–65% insoluble residue left after treatment for 30min. Under the condition of 350°C,
however, more than 90% of wood was decomposed and liquefied in all alcohols. Alcohols with longer alkyl chains liquefied lignocellulosics
in shorter reaction times. Because many kinds of alcohols, such as methanol and ethanol, can be produced from biomass, 100%
biomass-based liquid fuel can be prepared by supercritical alcohol technology when using such bioalcohols.
This study was presented in part at the 55th Annual Meeting of the Japan Wood Research Society, Kyoto, Japan, March 16–18,
2005 相似文献
139.
Structure and species diversity of subtropical evergreen broad-leaved forest in northern Okinawa Island, Japan 总被引:4,自引:0,他引:4
Xiaoniu Xu Eiji Hirata Yoshihiro Tokashiki Takeo Shinohara 《Journal of Forest Research》2001,6(3):203-210
The structure and tree species diversity of a subtropical evergreen broad-leaved forest in northern Okinawa Island, Japan,
were studied. Enumeration of the six sampling plots revealed an average density of 5,580 individuals with DBH≧3.0 cm/ha, having
an average basal area of 55 m2. The large-size trees of DBH≧20 cm contributed 10% of the total individuals, and 49% of the total basal area. The forest
showed a high diversity of tree species, which is comparable to some tropical rain forests. A total of 54 over-story species
of 24 families and a total of 63 understory species of 26 families were identified in the six sampling plots. Fagaceae and
Theaceae were the most important families;Castanopsis sieboldii, Schima wallichii andDistylium racemosum were the most important species. The diversity index and equitability index of species were 4.15 and 0.72 for the overstory
plots, and 4.72 and 0.79 for the understory subplots, respectively. The diversity index for the overstory was significantly
correlated to the total basal area of trees over 20 cm DBH (p<0.05) and the importance value ofC. sieboldii (p<0.001), while for understory, the diversity index was not correlated to the structural parameters (allp>0.16). The size distribution pattern and age structure indicated differences in regeneration strategies for canopy dominants.
In population dynamics of the succession process,C. sieboldii andD. racemosum were self-maintaining types, andS. wallichii was a gap- or opening-dependent type.
This study was made possible by support from the Japanese Ministry of Education, Sciences, Sports and Culture, which provided
a Monbusho scholarship to X.N. Xu. 相似文献
140.