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11.
From a nutritional perspective, rice flour is one of the most valuable flours and it is suitable for preparing food for people suffering from wheat allergy. However, bread made from rice flour is very difficult to bake because it lacks gluten. We found that pre-fermenting of rice flour using Aspergillus oryzae facilitated a better formulation of gluten-free rice bread. Bread swelling was remarkably improved with a longer pre-fermenting period at 55 °C. The specific loaf volume (SLV) without polymeric thickeners after a 12 h fermentation was approximately 2.2-fold (2.98 ml/g) higher than that after 0 h (1.36 ml/g). An enzymatic assay of the batter indicated that protease activity during the pre-fermentation period increased from 0.38 to 1.44 U/ml and this activity correlated with bread swelling. Furthermore, a commercial protease from A. oryzae also produced similar results with an adequate SLV of 3.03 ml/g. Rheological analysis showed that batter treated with protease had an increased batter viscosity and decreased flour settling behavior because of the aggregation of flour particle after partial cleavage of storage proteins. These results indicated that the improved SLV was mainly because of an A. oryzae protease, which affected the batter rheology thereby improving gas retention before baking.  相似文献   
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Porphyromonas gulae is black-pigmented anaerobic bacteria associated with canine periodontitis. There is little information available about the specific identify and relative occurrence of pigmented anaerobes in companion animals. Our aim was to clarify the factor involved in the adherence and colonization of the organism in the oral cavity. Fimbrial protein was purified from P. gulae ATCC 51700. The molecular mass of this protein was approximately 41kDa as estimated by SDS-PAGE. An antibody against 41-kDa fimbrial protein from P. gingivalis ATCC 33277 reacted with fimbrillin of P. gulae ATCC 51700. Immunogold electron microscopy revealed that the anti-41kDa fimbrial serum bound to fimbria on the cell surface of P. gulae ATCC 51700. Thus, fimbrial protein of P. gulae ATCC 51700 had the same size and antigenicity as 41-kDa fimbriae of P. gingivalis ATCC 33277. The nucleotide sequence of the fimA gene from P. gulae ATCC 51700 showed 94% homology with that of P. gingivalis ATCC 33277. Moreover, the deduced amino acid sequences have 96.8% identity. P. gulae has adherent ability to gingival epithelial cells. The properties of P. gulae fimbriae are similar to those of P. gingivalis fimbriae. We suggest that the surface structure of P. gulae may play a role in the colonization of this organism in periodontal pockets in companion animals.  相似文献   
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This study evaluated a vaccine made from crude rhoptry proteins of Toxoplasma gondii with Quil-A, which was administered to cats by the intranasal route. Eleven short-hair domestic cats were divided into four groups: G1 (n=3) received three doses (200 microg/dose) of the rhoptry vaccine with Quil-A (20 microg); G2 (n=3) received PBS with Quil-A (20 microg); G3 (n=3) and G4 (n=2) received only PBS. Treatments were administered at days 0, 21, and 42 by the intranasal route. Challenge was done to G1, G2, and G3 animals with 600 cysts of the VEG strain on day 51 (challenge day); G4 animals were unchallenged. The anti-T. gondii IgG and IgA antibody levels from sera were measured by indirect enzyme-linked immunosorbent assay (ELISA). At challenge, two animals from G1 revealed antibody levels for both IgG and IgA; oocysts were not detected in feces of these two cats. There were no differences in hematological values between groups throughout the experiment (p>0.10). Preventable fractions were 67% in G1 and 0% in G2 and G3. Comparatively, G1 animals shed 89.3% and 90.8% less oocysts than G3 and G4, respectively. Two out of three cats were protected against T. gondii oocyst shedding when the rhoptry vaccine was administered by the intranasal route. This is the first study using crude rhoptry proteins as vaccine by the intranasal route in cats to evaluate protection against oocysts shedding.  相似文献   
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The effect of feeding rotifers enriched with taurine on the growth performance and survival of larval amberjack Seriola dumerili was investigated. Rotifers were enriched with a commercial taurine supplement at four levels (0, 200, 400, and 800 mg/l). The larvae were fed the enriched rotifers in triplicate from 3 days post-hatch for 7 days under static conditions. The average taurine contents of the rotifers were 1.5, 2.7, 4.2, and 7.2 mg/g dry matter, respectively. The growth of the fish fed rotifers enriched with the taurine supplement at 800 mg/l was significantly (P < 0.05) improved compared with that of the fish fed the rotifers without taurine enrichment. The survival rate improved proportionally up to a taurine supplement level of 400 mg/l, but no significant differences in survival were observed among treatments. The fraction of the larvae with inflated swim bladders did not vary significantly between treatments. Taurine content in the whole fish body increased with the taurine level in the rotifers. These results suggest that taurine enrichment of rotifers is an effective method of enhancing the growth of amberjack larvae.  相似文献   
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The effect of docosahexaenoic acid (DHA) on the growth performance, survival and swim bladder inflation of larval Seriola dumerili during the rotifer feeding period was investigated in two feeding experiments. Amberjack larvae at 3 day post hatching were fed rotifers enriched with (1) freshwater C hlorella (Chlo), (2) a mixture (2:1, v/v) of Chlo and DHA‐enriched C hlorella (DHA‐Chlo), (3) DHA‐Chlo and (4) DHA‐Chlo and commercial DHA emulsion, in triplicate for 7 days. The average DHA contents of the rotifers were 0.0, 0.4, 1.0 and 1.9 mg g?1 DM respectively. The survival rate was improved by the enrichment of rotifers with DHA‐Chlo alone, and DHA‐Chlo and emulsion. Growth and swim bladder inflation of fish fed rotifers enriched with DHA‐Chlo were significantly (< 0.05) improved, however, with increased levels of DHA further improvement was not found. DHA content in the larval whole body proportionally increased with the DHA level in the rotifers. These results suggest that DHA enrichment of rotifers is effective to improve the growth, survival rate and swim bladder inflation of amberjack larvae. The DHA requirement of amberjack larvae is estimated to be 1.5 mg g?1 on a dry matter basis of rotifers.  相似文献   
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This study was conducted to evaluate the effects of iron glycine chelate (Fe‐Gly) on laying performance, antioxidant enzyme activities, serum biochemical indices and iron concentrations in laying hens. A total of 810 laying hens (Hy‐Line Variety White, 26 weeks old) were randomly assigned to six groups with five replicates of 27 layers. Hens in the control group received diet supplemented with 60 mg Fe/kg as FeSO4, while hens in other five groups received the diet supplemented with 0, 20, 40, 60 and 80 mg Fe/kg from Fe‐Gly respectively. The results showed that dietary Fe‐Gly treatments significantly influenced (p < 0.01) the laying rate and egg weight of layers, compared with the control group. Concerning to CuZn‐superoxide dismutase (CuZn‐SOD) and total superoxide dismutase (T‐SOD) activity, Fe‐Gly groups (60, 80 mg Fe/kg) were promoted significantly (p < 0.01) compared with 0 mg Fe/kg group. The concentrations of Fe in serum, liver, kidney, spleen and ovary were increased significantly with the level dietary Fe‐Gly raised where Fe‐Gly groups (60, 80 mg Fe/kg) had observably higher Fe concentration than the control (p < 0.01) in serum, kidney and spleen. There was a trend that transferrin mRNA expression was decreased with the increase of Fe as Fe‐Gly in diets, and compared with the control, the expression was lower in the group fed diet with 60 mg/kg Fe as Fe‐Gly. In conclusion, Fe‐Gly (60 mg Fe/kg) had improved laying rate, egg weight, SOD enzyme activity, Fe absorption and protein synthesis in body and promoted iron metabolism in laying hens. Moreover, Fe‐Gly (40 mg/kg Fe) had the similar effect with control group. It revealed that FeSO4 could be substituted by lower concentration of Fe‐Gly and Fe‐Gly may be superior to FeSO4 for iron fortification to laying hens.  相似文献   
20.
High linear energy transfer (LET) heavy charged particles have previously been applied clinically to human cancer radiotherapy because of their excellent physical properties of selective dose distribution and higher relative biological effectiveness (RBE) for human; however, such an approach has yet to be applied to cat patients. The present study investigates the biological effectiveness of low-LET gamma-rays (0.2 keV/micro m) compared to high-LET carbon ions (114 keV/micro m) in feline T- lymphocyte FeT-J cells. Clonogenic survival analysis revealed that the RBE value of carbon ions was 2.98 relative to a 10% survival dose (D(10)) by gamma-rays, and that the inactivation cross-section in cells exposed to gamma-rays and carbon ions was 0.023 and 38.9 micro m(2), respectively. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) analysis revealed that TUNEL-positive frequency in carbon-irradiation cells is higher than for gamma-irradiated cells against exposure to the same physical doses, but that very little difference in TUNEL-positive frequency is observed between cells exposed to the respective D(10) dose of gamma-rays. Our data thus indicate that carbon ions are more effective for cell killing than gamma-rays at the same physical doses, but kill cells to an extent that is comparable to gamma-rays at the same biological doses. Carbon ion radiotherapy is therefore a promising modality for cat patients.  相似文献   
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