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41.
42.
In vitro anti-rotavirus activity of Alpinia katsumadai (AK) extracts were evaluated against bovine G8P[7] and porcine G5P[7] rotaviruses in two different assay strategies, a mixed treatment assay and a post treatment assay. In the mixed treatment assay, six AK extracts [AK-1 (EtOH extract), AK-3 (H(2)O layer), AK-5 (40% methanol fraction), and AK-9-11 (H(2)O extract, polysaccharide fraction, supernatant fraction)] exhibited inhibitory activities against G5P[7] rotavirus with the EC(50) values ranging from 0.7±0.4 to 33.7±6.5 μg/mL. Extracts AK-1, AK-3, and AK-5 inhibited rotavirus infection against G8P[7] rotavirus, the with EC(50) values of 8.4±2.2 μg/mL, 6.5±0.8 μg/mL and 8.4±5.0 μg/mL, respectively. By hemagglutination inhibition (HI) assay, six AK extracts completely inhibited viral adsorption onto human RBCs in both strains of rotaviruses at less than 11 μg/mL. However, in the post treatment assay, there was no anti activity shown against both strains of rotaviruses. As a result, six AK extracts were attributed mainly to having a strong interaction with hemagglutinin protein on the outer surface of rotavirus, resulting to blockage of viral adsorption.  相似文献   
43.
Adrenomedullin (AM), a peptide identified to have vasodilating and natriuretic effects, is involved in the regulation of the cardiovascular system. To evaluate plasma AM concentration in dogs with myxomatous mitral valvular disease (MMVD), and to investigate the associations between the concentrations of plasma AM and natriuretic peptides and the echocardiographic data, we evaluated plasma AM concentrations in 31 healthy control dogs and 57 dogs with MMVD. Plasma AM concentrations in dogs with MMVD were higher than that in the control subjects. The plasma AM concentration increased in conjunction with the severity of heart failure according to the International Small Animal Cardiac Health Council (ISACHC). The AM concentrations were 25.1 ± 5.0 fmol/ml (ISACHC class Ia), 29.9 ± 11.0 fmol/ml (ISACHC class Ib), 43.4 ± 19.8 fmol/ml (ISACHC class II) and 73.5 ± 21.7 fmol/ml (ISACHC class III) and 7.5 ± 5.1 fmol/ml (control group), respectively. The receiver operating characteristic curve indicated an area of 0.93 (95% CI, 0.8801-0.9889; <0.0001), a cutoff value of 30.5 fmol/ml, a sensitivity of 87.1%, and a specificity of 82.5% for the determination of congestive heart failure. Plasma AM concentrations correlated with atrial natriuretic peptide concentrations, LA/Ao ratio, and left ventricular diameter. In conclusion, AM may be a potential diagnostic marker for canine MMVD and possibly plays a pathophysiological role in collaboration with the other neurohumoral factors such as natriuretic peptides.  相似文献   
44.
The present study investigated the effect of inclusion of multi-microbe probiotic product on growth performance, apparent digestibility of nutrients, cecal microbiota and small intestinal morphology in broilers. Four hundred days-old Ross chicks were randomly allotted to five treatments on the basis of body weight (BW). Each treatment had four replicates of 20 chicks in each. Experimental diets were fed in two phases, starter (day 0-21) and finisher (day 22-35). Dietary treatments were; basal diet without any antimicrobial (NC), basal diet added with 20 mg Avilamycin/kg of diet (PC), 10(7) cfu multi-microbe probiotic/kg of diet (P1), 10(8) cfu multi-microbe probiotic/kg of diet (P2), and 10(9) cfu multi-microbe probiotic/kg of diet (P3). Overall BW gain and feed conversion ratio were better (p < 0.05) for treatments PC, P2 and P3 compared with NC and P1, with P1 being better (p < 0.05) than NC. Overall feed intake in treatments PC, P1, P2 and P3 were greater (p < 0.05) than NC. Apparent digestibility of dry matter and crude protein were greater (p < 0.05) in treatments PC, P2 and P3 compared with NC, with P1 being intermediate and not different form NC, PC, P2 and P3. At d 21 and 35, treatments PC, P1, P2 and P3 showed lower (p < 0.05) cecal Clostridium and Coliforms count in relation to NC. Moreover, cecal Clostridium (d 21) and Coliforms (d 21 and 35) count were lower (p < 0.05) in treatment PC in relation to P1; with P2 and P3 being intermediate and not different from PC. However, there was no effect of dietary treatments on cecal total anaerobic bacteria and Bifidobacterium spp. count. The villus height of duodenum in treatment PC was greater (p < 0.05) than NC, with P1, P2 and P3 being intermediate. Villus height of ileum in treatment PC was greater (p < 0.05) than in treatments P1 and NC, whereas it remained comparable among treatments PC, P2 and P3. Villus height to crypt depth ratio of ileum was greater (p < 0.05) for treatment PC, P2 and P3 compared with that in P1 and NC. It is concluded that multi-microbe probiotic inclusion at 10(8) and 10(9) cfu/kg diet had beneficial effects on broilers growth performance, apparent digestibility of nutrients and intestinal morphology and can be used as replacement to antibiotics growth promoter in broiler nutrition.  相似文献   
45.
Alternative sources of mesenchymal stem cells (MSCs) for replacing bone marrow (BM) have been extensively investigated in the field of bone tissue engineering. The purpose of this study was to compare the osteogenic potential of canine MSCs derived from adipose tissue (AT), BM, umbilical cord blood (UCB), and Wharton''s jelly (WJ) using in vitro culture techniques and in vivo orthotopic implantation assays. After canine MSCs were isolated from various tissues, the proliferation and osteogenic potential along with vascular endothelial growth factor (VEGF) production were measured and compared in vitro. For the in vivo assay, MSCs derived from each type of tissue were mixed with β-tricalcium phosphate and implanted into segmental bone defects in dogs. Among the different types of MSCs, AT-MSCs had a higher proliferation potential and BM-MSCs produced the most VEGF. AT-MSCs and UCB-MSCs showed greater in vitro osteogenic potential compared to the other cells. Radiographic and histological analyses showed that all tested MSCs had similar osteogenic capacities, and the level of new bone formation was much higher with implants containing MSCs than cell-free implants. These results indicate that AT-MSCs, UCB-MSCs, and WJ-MSCs can potentially be used in place of BM-MSCs for clinical bone engineering procedures.  相似文献   
46.
This study was conducted to evaluate the growth characteristics and fatty acid composition among 15 kenaf mutants derived from the kenaf germplasm C14 and 15 kenaf accessions originating from Russia, India, China, Iran, and Italy. The overall growth performance (plant height, stem diameter, flowering date, leaf, and flower size) of the stem color mutant lines derived from C14 are similar to those of the original variety. However, the flower color mutant lines derived from C14 showed flowering to occur 10 days later when compared with the original variety and showed smaller leaf sizes than the original variety. Late-ripened kenaf accessions (Jinju, Auxu, and Jnagdae) can yield more bio-mass compared with early or medium-maturing germplasm. The late maturity kenaf (Auxu, Jinju, and Jangdae) has a higher oil percentage than the early maturity germplasm. Linoleic, oleic, and palmitic acids were the predominant fatty acids in all kenaf seeds. The stem color mutant lines significantly surpassed the parental means of all saturated fatty acids. In addition, the flower color mutant lines showed broad ranges of variation in oleic acid. The 15 accessions showed a wide range of fatty acid compositions, spanning from 29.75 to 38.30% saturated fatty acids and 61.70 to 70.24% total unsaturated fatty acids, and the late maturity kenaf has a higher linoleic acid percentage than the early maturity germplasm. The flowering period was highly positively (P ≤ 0.01) correlated with the plant height, stem diameter, oil percent, and linolenic acid (C18:3), and it was significantly negatively (P ≤ 0.01) correlated with stearic acid (C18:0). These results will provide valuable information to assist the parental selection of kenaf breeding.  相似文献   
47.
ABSTRACT

The sugar-accumulating potential of global and local sweet and grain sorghum varieties were tested under the local conditions. The basis for this study was the dependency of sugar accumulation on temperature and photoperiod. Thus, the efficacy of cultivars as a bioenergy source would need to be determined based on their performance under the local environmental conditions. A strong correlation of sucrose content with brix was observed, enabling large-scale screening of varieties for high sucrose content. The morphological characteristics inherent in sweet sorghum, such as tall stems, greater number of leaves and a longer vegetative period, were found to correlate with the total stem sugar content. Assessment of sugars along the stem revealed maximum sugar accumulation in the upper intermediate to upper internodes in most of the varieties tested. The maximum theoretical ethanol yield (MTEY), a function of brix and juice yield, was determined as a better indicator of testing the performance of a variety as a potential source of bioethanol, mainly due to a negative correlation of stem juiciness and sucrose content in the varieties tested. Further, the relative expression of vacuolar invertase genes, SbINV1 and SbINV2, was studied, and a strong negative correlation of SbINV2 to stem sucrose content was observed. This reveals a possibility of involvement of vacuolar invertase gene, SbINV2, in sugar accumulation in sweet sorghum stems, and as a key candidate for molecular breeding studies for higher stem sugar content.  相似文献   
48.
The microvasculature of the eyes of 5 rabbits was investigated using scanning electron microscopy on corrosion casts. The study revealed that the pars plana vessels draining blood from the iris and ciliary body coursed directly into the anterior vortex venous system constituting the scleral venous plexus (the venous circle of Hovius). The episcleral vasculature was found to possess a specialized morphology, with channels draining the aqueous humor. The capillaries of the third palpebral, bulbar and palpebral conjunctiva formed a single-layered capillary network approximately parallel to the epithelium and formed a well-developed venous plexus in the stroma. The retina was found to be merangiotic, meaning that vessels were present only in a small part of the retina, extending in a horizontal direction to form bands on either side of the optic disc. Channels representing the aqueous veins that drained blood mixed with aqueous humor were found to derive directly from the suprachoroidal space and communicate with the scleral venous plexus via the anterior vortex veins. The functional significance of the microvasculature of the iris, cilia, retina and choroid is discussed in this report as well. The elaborate microvasculature of the conjunctiva may be a prerequisite for the exchange of nutrients and gasses between the cornea and the vessels across the conjunctival epithelium when the eyelids are shut during sleep, and possibly for the dynamics of eye drop delivery. The scleral venous plexus in rabbits may be analogous to the scleral venous sinus (Schlemm's canal) in rats, primates and humans.  相似文献   
49.
A demand system analysis was conducted to examine the substitute relationships between tuna and skipjack tuna in the Japanese market. Data from the Annual Report on Family Income and Expenditure Survey from 1965 to 2006 were used for the analysis using the almost ideal demand system (AIDS). Results suggest that skipjack tuna can be a strong substitute for tuna, while other fish groups are not a clear substitute. Our analysis of substitute relationships among fish species in a market indicates that this is a factor that should be considered for better fisheries resource management. For instance, even under a situation where one fish species is underexploited, proper attention to its fishery management is necessary if the fish is a strong substitute for another popular fish species in the market.  相似文献   
50.
The new benzenesulfonylurea K-11451, an α-hydroxy-β-fluoropropyl- compound, applied at 3–9 g ha −1, controlled annual and perennial weeds grown in submerged paddy soil under greenhouse conditions. It effectively controlled barnyardgrass at growth stages varying from pre-emergence to the five-leaf stage. The compound inhibited acetolactate synthase, I50 values for the enzyme isolated from barnyardgrass and rice being 56 and 67 nM , respectively. K-11451 inhibited the growth of rice when it was transplanted at a shallow depth (0–1 cm) and water leaching from the paddy soil was high (3–5 cm per day). With a water depth of 3 cm, the compound appeared to move readily down into the paddy soil and had the relatively short half-life of 15.2 days under submerged paddy conditions. A mixture of K-11451 + mefenecet + daimuron (9 + 250 + 250 g ha−1) controlled almost all weeds in the paddy field without injury to rice, so that the combination could be used as a ‘one-shot’ herbicide in rice culture.  相似文献   
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