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71.
The effect of instant cooked rice made from giant embryo mutant or ordinary normal rice on the glucose metabolism and antioxidative defense system in mice under a high‐fat (HF) diet condition was investigated. The animals were randomly divided and given experimental diets for seven weeks: normal control diet, HF diet, and HF diet supplemented with instant normal white, normal brown, giant embryonic white, or giant embryonic brown rice. At the end of the experimental period, the HF mice showed a marked increase in the blood glucose level, insulin concentration, and plasma and erythrocyte lipid peroxidation and a significant decrease in the glycogen level relative to the control group. However, diet supplementation with instant cooked giant embryonic and normal brown rice counteracted this high‐fat‐induced hyperglycemia and oxidative stress through regulation of the glucose‐regulating and antioxidant enzyme activities. The giant embryonic brown rice was the most effective in improving the glucose metabolism and antioxidant defense status in mice under the HF diet condition. The results demonstrate that the giant embryo rice mutant may be useful in the development of instant cooked rice with strong hypoglycemic and antioxidative properties.  相似文献   
72.
A vital staining technique with fluorescein diacetate (FDA) and propidium iodide (PI) was used for determination of viability of myxosporean stage spores of Myxobolus artus and actinosporean stage spores of M. cultus . Viable spores stained green with FDA and non-viable spores stained red with PI were clearly distinguishable in M. artus myxosporean spores released from live infected fish, while the spores collected from pseudocysts were not well stained with FDA. Immediately after release from the oligochaete, Branchiura sowerbyi , actinosporean spores of M. cultus , stained bright green in the sporoplasms and red in the spore processes. In vitro survivability tests revealed that the longevity of M. artus spores was 5 months at 25°C and 15 months at 18°C. Drying and ultraviolet irradiation (36 000 mW s cm–2 for M. artus myxosporean spores, 600 mW s cm–2 for M. cultus actinosporean spores) were most effective as sporicidal treatments.  相似文献   
73.
The enhanced effect of cytokine combinations has been assessed empirically, based on their immunobiological mechanisms. However, far less is known of the enhanced protection of practical cytokine combinations against viral infection in the livestock industry, due to cost and production issues associated with mass administration. This study demonstrates the enhanced protection of oral co-administration of swine interferon-α (swIFN-α) and interleukin-18 (swIL-18) against infection with transmissible gastroenteritis virus (TGEV) in piglets using attenuated Salmonella enterica serovar Typhimurium as carrier of cytokine proteins. A single oral co-administration of S. enterica serovar Typhimurium expressing swIFN-α and swIL-18 induced enhanced alleviation of the severity of diarrhea caused by TGEV infection, compared to piglets administered S. enterica serovar Typhimurium expressing swIFN-α or swIL-18 alone. This enhancement was further observed by the reduction of TGEV shedding and replication, and the expression of IFN-stimulated gene products in the intestinal tract. The results suggest that the combined administration of the swIFN-α and swIL-18 cytokines using attenuated S. enterica serovar Typhimurium as an oral carrier provides enhanced protection against intestinal tract infection with TGEV.  相似文献   
74.
Because pigs have respiratory epitheliums which express both α2-3 and α2-6 linked sialic acid as receptors to influenza A viruses, they are regarded as mixing vessel for the generation of pandemic influenza viruses through genetic reassortment. A H7N2 influenza virus (A/swine/KU/16/2001) was isolated from pig lungs collected from the slaughterhouse. All eight genes of the influenza virus were sequenced and phylogenetic analysis indicated that A/swine/KU/16/2001 originated in Hong Kong and genetic reassortment had occurred between the avian H7N2 and H5N3 influenza viruses. The first isolation of H7 influenza virus in pigs provides the opportunity for genetic reassortment of influenza viruses with pandemic potential and emphasizes the importance of surveillance for atypical swine influenza viruses.  相似文献   
75.
Exposure of females to the male pheromone induces pulsatile release of gonadotropin-releasing hormone (GnRH) in goats. Recently, kisspeptin neurons in the arcuate nucleus (ARC) have been suggested to represent the proximate source of the GnRH pulse generator. In this study, we examined the effects of the pheromone on multiple-unit activity (MUA) in female goats fitted with recording electrodes aimed at the ARC kisspeptin neurons. In all eight goats, periodic bursts in MUA (MUA volleys), which were considered to be electrophysiological manifestations of the GnRH pulse generator, were observed. The mean intervolley interval (T) during the control period was calculated in each goat that was then exposed to the male pheromone for 1 sec at timings of 1/4 T, 1/2 T or 3/4 T after one regularly occurring MUA volley. An instantaneous rise in MUA was observed immediately after the exposure regardless of timing. Exposure at a timing of 3/4 T resulted in an MUA volley within 60 sec following the instantaneous rise in all goats. In contrast, an MUA volley was induced in only 2 goats by exposure at 1/2 T, while exposure at 1/4 T failed to induce an MUA volley in any goats. These results suggest that transmission of the pheromone signal to the ARC, represented by an instantaneous rise, activates the GnRH pulse generator. Moreover, the timing-dependent pheromone action in inducing an MUA volley indicates that the GnRH pulse generator has a refractory period for the pheromone signal after the burst.  相似文献   
76.
1. Chronic administration of a glycoprotein fraction from chicken pituitary using an ALZET osmotic pump at 12.5 micrograms/h for 2 weeks induced growth of ovarian follicles to a mature size in the ovary and deposition of yolk in sexually immature 6-week-old Japanese quail females which were kept under 8L:16D short-day conditions. However, no ovulation was induced in these birds. 2. Injection of 500 micrograms of the glycoprotein into other immature short-day females was performed following the above chronic administration, 12 or 14 and 15 d after implantation of the osmotic pump. About 24 h after injection, 3 of 14 females laid one or two eggs. Ovulation was confirmed in 4 females by autopsy. A total of 5 of 14 females ovulated 6 eggs, and significant development of the oviduct and the cloacal opening were observed in all of the treated females. 3. Thus, complete ovarian function could be induced in sexually immature female Japanese quail by administration of avian gonadotrophin using a combination of an osmotic pump and an injection.  相似文献   
77.
This study evaluated the suitability of using a chitosan formulation as an adjuvant to enhance both the mucosal and systemic immune responses against recombinant transferrin-binding protein B (rTbp B) of Actinobacillus pleuropneumoniae via direct tracheal administration. The chitosan formulation was found to enhance mucosal immune response, as measured by the secretory IgA level in lung lavage fluid and lung homogenate extracts, and systemic immune response, as measured by the serum IgG level.  相似文献   
78.
In this study, we examined the effects of a dextran-modified silk fibroin nanofibrous mat (D-SFNM) on wound healing. To increase the hydrophilicity of silk fibroin (SF), the SF nanofibrous mat (SFNM) was modified with oxidized dextran. The D-SFNM absorbed water faster than the SFNM, and the swelling ratio was increased by approximately 80 % compared with the SFNM. An in vitro cell (NIH3T3) test revealed that fewer cells attached to the D-SFNM than the SFNM, but the proliferation of cells was not significantly affected by the presence of dextran. An in vivo wound healing test with mice indicated that the D-SFNM resulted in a good wound recovery effect similar to a commercial wound dressing material. The increased hydrophilicity of the D-SFNM might balance the moist environment at the wound site, which improves the wound healing compared with the SFNM.  相似文献   
79.
A suspension copolymerization in the presence of aqueous radiopaque nanoparticles was used to prepare poly(vinyl pivalate/vinyl acetate) (P(VPi/VAc)) nanocomposite microspheres for embolic materials. To generate nanocomposite microspheres with radiopacity, various radiopaque nanoparticles (TiO2, Ti, Ag, Au and Pt) were added to P(VPi/VAc) copolymer. The P(VPi/VAc)/nanoparticles microspheres with radiopacity were then saponified in alkali solution, leading to syndiotactic poly(vinyl alcohol) (s-PVA)/nanoparticles microspheres with radiopacity of which degree of saponification (DS) was up to 99.8 %. The saponification time of P(VPi/VAc)/nanoparticles microspheres decreased with increasing the amount of nanoparticles. Computed tomography (CT) analysis revealed that s-PVA/TiO2 and s-PVA/Ti microspheres had good radiopacity.  相似文献   
80.
Poly(vinyl alcohol) (PVA)/Ag-zeolite nanocomposite hydrogels were prepared by UV irradiation using PVA solution mixed with Ag-zeolite nanoparticles. Physical properties and changes in morphology of the PVA/Ag-zeolite hydrogels were investigated. The PVA/Ag-zeolite hydrogels were prepared at a PVA concentration of 9 wt% with a UV irradiation distance of 15 cm, where gel fraction and swelling ratio were optimized. Hardness of the PVA/Ag-zeolite hydrogels decreased with increasing amounts of Ag-zeolite, reaching that of soft elastomer when the amount of Ag-zeolite was 5 % by weight. The PVA/Ag-zeolite hydrogels showed strong antimicrobial activities against Staphylococcus aureus and Klebsiella pneumoniae, inducing a reduction of bacteria of over 99.9 % at a Ag-zeolite content of 3 wt%.  相似文献   
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