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61.
A comparative analysis of the elasticity, microstructure and thermal stability of fibres (thickness ranging from 43.4 to 189.4 µm) isolated from pineapple leaves (PALF), coconut coir (COIR), banana leaf-stem (BAN) and oil palm empty fruit bunch (OPEFB) reported in this study. Statistical analysis of the mechanical properties derived from tensile test to rupture reveals significant differences (P<0.05) in the fibre strength (σ), stiffness (E) and extensibility (parameterized by the strain to rupture, ?). It is observed that COIR fibres yield the smallest strength, σ (=99.8±22.5 MPa), and stiffness, E (= 0.5±0.1 GPa), while PALF fibres yield the largest σ (=639.5±301.6 MPa) and E (=7.1±3.1 GPa); PALF fibres exhibit the smallest ? (=0.11±0.03) but OPEFB fibres yield the largest ? (=2.0±1.3). From scanning electron micrographs, it is observed that cellulose fibril rupture predominates in OPEFB, COIR and BAN fibres; a large proportion of the cellulose fibrils fail by pullout in PALF fibres. Thermogravimetric analysis reveals that all fibres are thermally stable up to 250 °C; the fibre residue ranges from 30 to 80 wt% after heating to 500 °C. In particular, BAN experiences the highest weight loss and PALF experiences the lowest weight loss. The findings lend to a simple approach for determining the performance of the composites by assessing the type of natural fibres for reinforcing polymeric matrices.  相似文献   
62.
Inflammatory colorectal polyps (ICRPs) in miniature dachshunds are recently recognized as a major cause of large bowel diarrhea in this dog breed in Japan. ICRPs are characterized by the formation of multiple small polyps and a space-occupying large polyp in the colorectal area, and are thought to be a novel form of inflammatory bowel disease (IBD). In humans, specific cytokine patterns attributed to T helper (Th)1, Th17 and regulatory T cells have important roles in the pathogenesis of IBD. Thus, the aim of the present study was to assess the gene expression of cytokines of T cell subsets in the colorectal mucosa from dogs with ICRPs. Colorectal mucosal specimens from 10 dogs with ICRPs and 14 control dogs were used in this study. Interferon (IFN)-γ, interleukin (IL)-4, IL-17A and IL-10 mRNA expression was assessed using quantitative real-time PCR. IL-17A mRNA expression was significantly increased in large polyps compared to small polyps and controls. IFN-γ and IL-10 mRNA expression in large polyps were significantly higher than in controls. There was no significant difference in IL-4 mRNA expression among the three groups. IL-17A is thought to play important roles in the pathogenesis of ICRPs. IL-10 up-regulation could oppose the proinflammatory function of IL-17A.  相似文献   
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Mistletoes are parasite plants growing on various tree species,taking nutrients from the host.Beneficial compounds of mistletoe were used in medicine and these mistletoes were commonly collected from oak species that were not well identified.We analyzed the nutritional value by measuring proximate and mineral components of Korean mistletoe(Viscum album var.coloratum)from various host trees.Carbohydrate was the most proximate component in both leaves and twigs followed crude protein,crude fiber,crude ash and crude fat.While the contents of the proximate components and minerals varied among hosts and between plant parts,leaves contained higher crude protein and ash,and more minerals except for magnesium than twigs,although no significant difference was found inmistletoe grown on Prunus mandshurica.There were significant differences of proximate and mineral contents depending on the host species.Mistletoe grown on Chaenomeles sinensis contained higher levels of carbohydrates,crude fat,crude ash,magnesium,calcium,sodium,iron,and zinc than mistletoe grown on other species.Mistletoe grown on P.mandshurica contained high mineral levels of potassium,copper and phosphorous.The nutritional value of mistletoes were greatly influenced by the host species but among the hosts,specific nutrients accumulated in leaves more than in twigs,and vice versa.Based on the analysis,Korean mistletoe contains relatively good quality of nutrients and has high potential for dietary supplements as well as for medicinal compounds.  相似文献   
65.
Plant Foods for Human Nutrition - Cancer is a preventable and treatable disease, however, the incidence rates are on the rise. Classical treatment modalities for cancer include surgery,...  相似文献   
66.
Paddy and Water Environment - This study examines the effects of future climate changes on watershed hydroecology, including runoff, evapotranspiration, soil moisture content, gross primary...  相似文献   
67.
A 12‐week feeding trial was designed to assess the probiotic potential of indigenous Bacillus amyloliquefaciens and/or Bacillus subtilis singly or in combination with Bacillus licheniformis in an extruded feed for olive flounder (Paralichthys olivaceus) juveniles. A high fish meal (FM) diet (control) and a low‐FM diet containing an alternative protein blend (30% FM replacement, FM30) were formulated. Three other experimental diets were prepared by inclusion of B. amyloliquefaciens (BA), B. subtilis (BS), or a mixture of B. amyloliquefaciens, B. subtilis, and B. licheniformis (BASL) into FM30 diet, with a final concentration of 106 CFU/g diet. Results indicated that the FM30 diet was well tolerated by flounder, and the overall performance was not affected by dietary treatments. Lysozyme activity and total immunoglobulin level were significantly reduced in flounders when fed with the FM30 diet compared with the BASL and BA diets, respectively. The Bacillus additives neither enriched the relative abundance of the corresponding Bacillus spp. in the relevant gut microbiota of olive flounder nor modulated the presumptive gene functions of the gut microbiome. Despite the absence of growth‐promoting effect, the tested probiotics could still be economically viable for use as immunostimulants in commercial flounder diets with partial FM replacement.  相似文献   
68.
Disease has become an increasingly important issue for wildlife management over the past two decades. Adequate surveillance is fundamental for disease prevention and control, thus there is an increasing need for diagnostic assays for wildlife management. The objective of this study was to evaluate the performance of a field-portable biosensor adapted for rapid detection of specific antibodies in tortoise plasma that reflect a history of exposure to Mycoplasma agassizii, which is an agent of tortoise upper respiratory tract disease. Banked plasma samples were tested in two blinded trials, and the parameters that define the reliability of a diagnostic test were estimated based on externally validated tortoise plasma controls. The mean sensitivity of the biosensor (ability to identify exposed tortoises in the group of all exposed individuals) was 78%; the mean specificity (unexposed individuals with negative test result, out of all unexposed individuals tested) was 73%; the mean positive predictive value (exposed individuals with positive test, out of all individuals with positive test) was 82%; the mean negative predictive value (unexposed individuals with negative test, out of all individuals with negative test) was 68%. In a 15-min field-portable format, the biosensor was able to discriminate between true seropositive (n=34) and true seronegative (n=23) tortoise plasma with overall accuracy of 84%. The goals established for the tortoise population can help managers decide whether potential diagnostic errors should impact management decision-making, and whether the benefits of the field-portable format of the biosensor assay outweigh any potential disadvantages.  相似文献   
69.
Enrofloxacin, a fluoroquinolone antibiotic has been used widely in humans and domestic animals, including dogs, because of its broad-spectrum activity and relative safety. The side effects of fluoroquinolone, induced tendinopathy, tendonitis, spontaneous tendon rupture and cartilage damage, remain incompletely understood. In the present study, we investigated the in vitro effects of enrofloxacin on cell proliferation and induction of apoptosis in canine Achilles tendon cells and chondrocytes. Cell growth and proliferation after treating with enrofloxacin for 2–6 days was quantified by a colorimetric 2,3-bis{2-methoxy-4-nitro-5-sulfophenyl}-2H-tetrazolium-5-carboxyanilide inner salt (XTT) assay. The results showed that enrofloxacin could inhibit the proliferation of canine tendon cells and chondrocytes at increasing concentrations (10–200 μg/ml). The inhibition of proliferation of canine tendon cells and chondrocytes after exposure to enrofloxacin were associated with induction of apoptosis, as evidenced by the typical nuclear apoptotic condensed nuclei found using Hoechst 33258 staining. It was demonstrated that canine tendon cells and chondrocytes treated with 200 μg/ml enrofloxacin for 4 days exhibited apoptotic features and fragmentation of DNA. Enrofloxacin also increased the apoptosis of canine tendon cells and chondrocytes in a dose and time-dependent manner. The results indicate that enrofloxacin inhibits cell proliferation, induces apoptosis and DNA fragmentation, which might explain enrofloxacin-induced tendinopathy and cartilage damage.  相似文献   
70.
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