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131.
Dendritic cells (DCs) are specialized antigen presenting cells specializing in antigen uptake and processing, and play an important role in the innate and adaptive immune response. A subset of bovine peripheral blood DCs was identified as CD172a+/CD11c+/MHC (major histocompatibility complex) class II+ cells. Although DCs are identified at 0.1%–0.7% of peripheral blood mononuclear cells (PBMC), the phenotype and function of DCs remain poorly understood with regard to maintaining tolerance during the pregnancy. All cattle used in this study were 1 month before parturition. We have established a novel method for the purification of DCs from PBMC using magnetic‐activated cell sorting, and purified the CD172a+/CD11c+ DCs, with high expression of MHC class II and CD40, at 84.8% purity. There were individual differences in the expressions of CD205 and co‐stimulatory molecules CD80 and CD86 on DCs. There were positive correlations between expression of cytokine and co‐stimulatory molecules in DCs, and the DCs maintained their immune tolerance, evidenced by their low expressions of the co‐stimulatory molecules and cytokine production. These results suggest that before parturition a half of DCs may be immature and tend to maintain tolerance based on the low cytokine production, and the other DCs with high co‐stimulatory molecules may already have the ability of modulating the T‐cell linage.  相似文献   
132.
Airag, (Fermented horse milk) is a traditional milk product in Mongolia. Herders separate foals from their dams and tie them at a milking site during the daytime to produce airag. To evaluate the effects of horse management on the movement of dams, we tracked three dams in a herd in camp 1 during summer and camp 2 during autumn of 2013 and analyzed their movements during the milking (daytime) and non‐milking (nighttime) periods in an area famous for its high‐quality airag. Dams were gathered every 1.7 ± 0.0 h between 07.46 and 15.47 hours at the milking sites and milked 4.6 ± 0.2 times/day during the study period (86 days). Daily cumulative and maximum linear distances from the milking sites were longer (< 0.01) during the non‐milking period than during the milking period. Daily home ranges were 91 and 26 times greater during the non‐milking period (< 0.001) in camps 1 and 2, respectively. The greater range during the non‐milking period would reflect the spatial distributions of water, salt and forage. The dams initially used similar areas and gradually shifted their daily home ranges after several days. This shift suggests that the dams grazed farther afield as forage availability declined around the milking site. For better airag production and sustainable pasture use, our results provide insights useful for evaluating the effects of milking management on vegetation and soil in those pastures, for selecting the appropriate milking times and frequency, and for choosing the right timing to shift milking sites.  相似文献   
133.
An R664X nonsense mutant AE1 is responsible for dominant hereditary spherocytosis in cattle and is degraded by the proteasomal endoplasmic reticulum-associated degradation. The present study demonstrated that R664X AE1 translated in vitro had the trypsin-sensitve site identical to that of the wild-type AE1. The P661S/R664X mutant containing a possible N-glycosylation site at Asn660 showed an increase in size by 3 kDa both in the cell-free translation system and in transfected HEK293 cells. Moreover, steady state levels of R664X and P661S/R664X in HEK293 cells were markedly increased in the presence of a proteasome inhibitior. These findings indicate that the truncated C-terminal region of R664X AE1 has lumenal localization in the endoplasmic reticulum and is not accessible to proteasomal machineries in the cytosol.  相似文献   
134.
A boron-containing pectic polysaccharide was isolated from Driselase digests of akamatsu (Pinus densiflora) cell wall. The boron-containing polysaccharide was purified by successive column chromatography of Cosmosil C18 OPN, DEAE Sepharose FF, and Superdex 75. The complex had 0.12% (w/w) boron (B) and11B-NMR spectroscopy showed the complex to be the tetrahedral diester form of boron. The sugar composition and glycosyl linkage analyses showed that the sugar portion of the complex was rhamnogalacturonan-II (RG-11). The boron-attached glycosyl residue was identified to be 2-O-Me-xylose-containing apiosyl side chain in RG-II. These results established that the location of borate in the cell wall is conserved among dicots, gramineous monocots, and coniferous gymnosperm.Part of this study was presented at the 8th Cell Wall Symposium, Norwich, September 3, 1998  相似文献   
135.
Anionic emulsion sizes consisting of rosin triglyceride esters and partly fortified rosin acids (i.e., rosin-ester sizes), have recently been used as internal sizes for alkaline papermaking. In this study, handsheets were prepared from pulp suspensions with alum and a rosin-ester size under various conditions, and sizing degree and size and aluminum contents of the handsheets were determined. Aluminum compounds originating from alum added to the pulp suspensions behave as retention aids of the rosin-ester size even in alkaline papermaking under limited conditions. Carboxyl groups in pulp are the primary retention sites of aluminum compounds in pulp suspensions. They form cationic sites on pulp fibers, and thus the anionic size emulsion particles are adsorbed on pulp fibers by electrostatic interactions. However, the cationic charges of aluminum compounds on pulp fibers decrease and finally disappear completely with the lapse of time after the alum addition by forming ionic bonds between the cationic sites and OH ions. Thus, pH values of the pulp suspensions and timing of the size addition strongly influence the retention values of the rosin-ester size and the resultant sizing features.This research was presented in part at the 1995 autumn meetings of the Society of Fiber Science and Technology Japan in Hamamatsu, October 1995  相似文献   
136.
Four Missouri stalagmites yield consistent overlapping records of oxygen and carbon isotopic changes and provide a climate and vegetation history with submillennial resolution from 75 to 25 thousand years ago (ka). The thorium-230-dated records reveal that between 75 and 55 ka, the midcontinental climate oscillated on millennial time scales between cold and warm, and vegetation alternated among forest, savanna, and prairie. Temperatures were highest and prairie vegetation peaked between 59 and 55 ka. Climate cooled and forest replaced grassland at 55 ka, when global ice sheets began to build during the early part of Marine Oxygen Isotope Stage 3.  相似文献   
137.
The rheological properties of cooked white salted noodles made from eight wheat cultivars with varied amylose content were analyzed at small and large deformation. Their dynamic shear viscoelasticity was measured using a rheometer with parallel plate geometry. Compressive force and creep‐recovery curves were measured using various probes and sample shapes. Noodles with lower amylose content showed a lower storage shear modulus (G′) and a higher frequency dependence of G′. The G′ values of noodles were highly correlated with amylose content in wheat flour and with G′ values of 30 and 40% starch gels. Remarkable differences in the characteristics of creep‐recovery curves were observed between cultivars. The difference in amylose content in wheat flour reflected the creep‐recovery properties of noodles. A negative correlation was demonstrated between amylose content and both maximum creep and recovery compliance. The compressive force required for 20, 50, 80, and 95% strains was compared. At 20 and 50% strain, noodles made from lower amylose wheat flour showed lower compressive force. Noodles of waxy wheat had a higher compressive force than nonwaxy noodles when the strain was >80%, indicating the waxy wheat noodles are soft but difficult to completely cut through.  相似文献   
138.
To investigate the structure of porcine genes involved in the beta-oxidation of fatty acid, we isolated the short-chain acyl-CoA dehydrogenase (SCAD), medium-chain acyl-CoA dehydrogenase (MCAD), and long-chain acyl-CoA dehydrogenase (LCAD) genes from the pig. The cDNA of SCAD, MCAD and LCAD genes were 1899 bp, 1835 bp 1835 bp and 1704 bp long and coded for 413-aa, 422-aa and 430-aa precursor proteins, respectively. Three genes, SCAD, MCAD and LCAD were mapped to 14p16.2-23.2, 6q32.4-33, and 15q24.2-26.3, respectively.  相似文献   
139.
The effects of feed restriction, cold exposure, and the initiation of feeding on blood glucose metabolism, other blood metabolites, hormones, and tissue responsiveness and sensitivity to insulin were measured in sheep. The sheep consumed orchardgrass hay ad libitum (AL) or were restricted to 82% of the ME requirement for maintenance (RE) and were exposed to a thermoneutral (20 degrees C) or a cold environment (2 degrees C). An isotope dilution method and a glucose clamp approach were applied to determine blood glucose metabolism and insulin action, respectively. Plasma NEFA and insulin concentrations were influenced by feed restriction. Concentrations of plasma glucose, NEFA, insulin, and glucagon were influenced by cold exposure. Plasma NEFA concentration for RE decreased after the initiation of feeding and plasma insulin concentration increased transiently for all treatments. [U-13C]Glucose was continuously infused for 8 or 7 h after a priming injection starting 3 h before the initiation of either feeding or insulin infusion, respectively. When responses to feeding were studied, blood glucose turnover rate was less (P < .001) for RE than for AL, and it was greater (P < .001) during cold exposure than in the thermoneutral environment. The rate changed little after the initiation of feeding. For the glucose clamp approach, insulin was infused over four sequential 1-h periods at rates from .64 to 10 mU x kg BW(-1) x min(-1), with concomitant glucose infusion to maintain preinfusion plasma glucose concentrations. The rates of glucose infusion and blood glucose turnover increased (P < .001) dose-dependently with insulin infusion rate. The maximal glucose infusion rate was greater (P < .05) for RE than for AL and was greater (P < .001) during cold exposure than in the thermoneutral environment. The plasma insulin concentration at half-maximal glucose infusion rate was lower (P < .1) during cold exposure. Blood glucose turnover rate tended to be greater (P = .10) for RE than for AL, and it was greater (P < .001) during cold exposure than in the thermoneutral environment. The ratio of endogenous production to utilization of glucose was suppressed by insulin infusion. In sheep fed a roughage diet, blood glucose turnover rate seems to be influenced by both intake level and environmental temperature, but not by the act of feeding. Moreover, the action of insulin on glucose metabolism is enhanced during cold exposure, and the effect of feed restriction is somewhat enhanced.  相似文献   
140.
This study was carried out to investigate whether expensive enzyme-treated fish meal (EFM) can be partially replaced by soybean meal (SM) or enzyme-treated SM (ESM) without compromising the growth of captive-raised Pacific bluefin tuna (PBT) juveniles. Five fish diets were tested: EFM (control) and EFM in which 10 or 20% of the EFM was replaced with either ESM or SM (ESM10, ESM20, SM10 and SM20, respectively). The respective diets were provided to 28-day-old PBT juveniles (mean body weight approx. 0.38 g) stocked randomly in 15-m3 tanks (276 juveniles per tank; two tanks per treatment) for 12 days. The final mean body weight of PBT juveniles on diets EFM, SM10, and SM20 was significantly higher than that of juveniles on diet ESM20. Although daily feeding rate was significantly higher in the ESM and SM groups, feed efficiency (FE) was significantly higher in the EFM group; there was no significant difference between juveniles fed diets EFM and SM10. Protein and phosphorus retention efficiency were significantly lower in the ESM20, and ESM20 and EFM groups, respectively. Phosphorus discharge was significantly lower in the SM groups. The results demonstrate that 10% SM (11% EFM replacement) can be included in EFM without compromising the growth performance of PBT juveniles.  相似文献   
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