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21.
Breads baked from wheat flours (protein contents 14.1–16.5% at 14.0% mb) that were pretreated with 2–3 mL of gaseous acetic acid per kg of wheat flour, showed maximum bread height and specific volume (cm3/g). Flour-water suspension and the crumb pH values were gradually decreased with increased amounts of acetic acid. Gas generation and dough expansion tests with bread dough showed that the addition of the same amount of acetic acid, which achieved maximum specific volume, also showed the highest rate of gas generation and dough expansion. However, increasing acetic acid decreased these values. Scanning electron microscope (Cryo-SEM) observation showed that the bread dough made from the same acetic acid-treated flour indicated continuum and no cracks in the dough matrix. Evaluation of mixograms showed the decrease of mixing stability with increased acetic acid levels. Viscosity and water binding capacity of flour-water suspensions were sharply increased by the addition of acetic acid at pH 5.0–3.5.  相似文献   
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The aim of this study was to clarify the hormonal and immunological changes in periparturient dairy cows with excessive weight loss following calving. We analyzed leukocyte populations and the peripheral blood mononuclear cell (PBMC) mRNA of IFN-gamma, IL-4, growth hormone (GH)-receptor (R) and insulin -R and measured the GH and insulin concentrations. Ten dairy cows fed in one herd were used in this study and were divided into two groups. Five cows that experienced loss of body weight following calving of over 10% comprised the Weight Loss Group, and the remaining five cows, which experienced loss of body weight of 5% or less following calving, served as the Control Group. The Weight Loss Group had high serum cholesterol and low blood urea nitrogen levels compared with the Control Group throughout the period of observation. In regard to the leukocyte populations, there were significantly fewer CD4(+)CD45R-T cells in the Weight Loss Group 1 to 2 months after calving compared with the Control Group. The percentage of IFN-gamma/IL-4 among PBMCs in the Weight Loss Group tended to be lower than in the Control Group throughout the observation period. In the Weight Loss Group, the levels of GH-R during month 2 were lower than in the Control Group. We concluded that excessive loss of body weight in dairy cows following calving is associated with depressed cellular immune function.  相似文献   
24.
The effects of mycotoxins on mitogen-stimulated proliferation of bovine peripheral blood mononuclear cells (PBMCs) were investigated. Aflatoxin B(1) (AFB(1)), deoxynivalenol (DON) and zearalenone (ZEN) were added to cultures of PBMCs, and the proliferation responses were measured using MTT bioassays. Suppression of the proliferation of calf PBMCs by AFB(1) and DON was significantly stronger than that of cow PBMCs, whereas there were no differences in suppressive effects on PBMCs from Holstein and Japanese Black calves and cows. The suppressive effect was greatest in the order of DON, AFB(1) and ZEN, and the effects of DON and AFB(1) seemed to be dose-dependent. The results suggest that some mycotoxins directly suppress proliferation of bovine PBMCs.  相似文献   
25.
To clarify the relationship between cellular immune status and nutritive condition, feeding program, blood profiles, and leukocyte populations were analyzed in two dairy herds experiencing frequent mastitis. Fourteen of the 35 lactating cows in herd A, and 18 of the 50 lactating cows in herd B scored positive on the California Mastitis Test (CMT), and 3 of the 73 lactating cows were CMT positive in herd C, which was the control. All herds were evaluated during five different milking stages, and blood was collected from five cows at each stage. With regard to feed content, the percentages of total digestible nutrients (TDN) and crude protein (CP) were found to be lower in herds A and B than in herd C. Levels of serum total cholesterol and blood urea nitrogen were lower in herds A and B than those in herd C. Neutrophil counts in herds A and B were increased compared to the neutrophil counts in herd C. On the other hand, the numbers of CD3(+) T cells and CD14-MHC class(+) cells were lower in herd A and B than in herd C. A decrease in peripheral lymphocytes and undernourishment were observed in the herds with frequent occurring mastitis.  相似文献   
26.
We examined the effects of heavy-ion bombardment on mutagenesis in sweet pepper (Capsicum annuum L.). Dose–response studies indicated that 10 Gy irradiation of 12C or 20Ne ions on dry seeds is suitable for inducing mutations in plants. From 20Ne-irradiated M1 plants, putative mutants included two dwarf plants and one plant whose pericarp was yellow were isolated. Phenotypes of their M2 progeny were similar to those of the M1 plants and did not segregate. F1 plants resulting from reciprocal crosses between the mutants and wild-type plants showed the wild-type phenotype, but phenotypes of F2 and BC1F1 segregated at 1:3 (mutant:wild) and 1:1, respectively. These crossing experiments indicate that the three mutants have monogenic recessive mutations in nuclear genes. In light of these data, we discuss the effectiveness of using heavy-ion bombardment to mutate sweet peppers.  相似文献   
27.
To plan a serial order behavior, we hold serial sensory information in our minds and convert it to a movement program. We trained monkeys to memorize a sequence of positional cues and to reproduce it by making saccades in either the original or reverse order. The order was determined in the middle of a trial on the basis of an instruction stimulus. Triggered by the instruction stimulus, single neurons in the dorsal premotor cortex became transiently active only when the order needed to be determined. These transient neurons, together with nearby sustained neurons that hold information on cue or movement sequences, appear to mediate the generation of a motor program from the maintained information.  相似文献   
28.
House dust mite (HDM) allergens are the most common allergens for induction of IgE-mediated hypersensitivity. Recently, epicutaneous sensitization with HDM allergens has been emphasized in the development of atopic dermatitis (AD) by producing various soluble factors in keratinocytes. Among the soluble factors, GM-CSF is a key molecule that activates Langerhans cells, antigen-presenting cells in the epidermis. In the present study, we investigated the effects of Dermatophagoides farinae (Der f) on GM-CSF production in a canine keratinocyte cell line, CPEK. CPEKs were found to produce GM-CSF upon stimulation by Der f. The GM-CSF production was suppressed by addition of a cysteine protease inhibitor. The present results suggest that cysteine protease-derived Der f may be an initiator of allergic inflammation by inducing the production of GM-CSF in keratinocytes.  相似文献   
29.
To investigate morphological acclimation to differences in nutrient availability, we compared shoot and needle morphology of Picea glehnii (Friedr. Schmidt) M. T. Mast. and Picea jezoensis (Siebold & Zucc.) Carrière trees growing on nutrient-poor volcanic ash and nutrient-rich, brown forest soil. Trees of both species were shorter and had more open canopies when growing on volcanic ash than when growing on brown forest soil. Nutrient-poor conditions limited height growth less in P. glehnii than in P. jezoensis. In both species, trees growing on volcanic ash had shorter annual increments in the previous year and more needles per shoot length and, hence, a smaller shoot silhouette area (SSA) relative to needle dry mass (NDM) than trees growing on brown forest soil. Soil type had less effect on shoot projected needle area (PNA). Total needle area (TNA) of P. glehnii shoots was similar between soil types, whereas TNA of P. jezoensis was lower in trees growing on volcanic ash than in trees growing on brown forest soil. For both species, low SSA in response to nutrient-poor conditions resulted in low shoot SSA/PNA ratios, indicating high within-shoot self-shading. Shoot SSA/TNA of P. glehnii was lower in trees growing on volcanic ash than in trees growing on brown forest soil, indicating that needles were sun-acclimated. In contrast, shoot SSA/TNA of P. jezoensis was higher in trees growing on volcanic ash than in trees growing on brown forest soil. The contrasting response of TNA to low nutrient availability was associated with species-specific differences in needle morphology. Needles of P. glehnii growing on volcanic ash were slightly shorter, wider, thicker and heavier than those of trees growing on brown forest soil, indicating morphological acclimation to high irradiance. Needles of P. jezoensis growing on volcanic ash were shorter than those of trees growing on brown forest soil, but did not show morphological acclimation to high irradiance in width, thickness or mass. For both species, nutrient-poor conditions decreased maximum photosynthetic rate (Amax) per NDM. However, when expressed per PNA, the decrease in Amax was reduced, and when expressed per SSA, Amax was higher in trees growing on volcanic ash than in trees growing on brown forest soil. On volcanic ash, Amax per NDM was lower for P. glehnii than for P. jezoensis. However, morphological changes at the shoot and needle levels reversed this trend when Amax was expressed per SSA or per PNA. The species-specific differences in morphological response to differences in soil nutrient availability suggest that P. glehnii is more tolerant of nutrient-poor conditions, whereas P. jezoensis is better at exploiting nutrient-rich soils.  相似文献   
30.
Karkade (Hibiscus sabdariffa) was blended with wheat flour to make bread. When 0.5% Karkade was blended with wheat flour, maximum bread height and specific volume (cm3/g) were obtained (pH 4.8–5.0); these properties gradually deteriorated with increased Karkade. The pH of the bread crumb decreased with increased Karkade, reaching pH 3.35 when blended with 10% Karkade. The pH of Karkade alone was 2.5, which was adjusted to ≈5.0 by the addition of alkali just before blending with wheat flour and making bread. Control of the Karkade pH resulted in bread height and specific volume recovering to the original optimal levels. In addition, the deep reddish purple color (513 nm) of the bread crumb changed to a brownish color crumb. The Fe content was 0.14 mg of Fe/gram of dry crumb, or 6.22 mg of Fe/60 g of fresh bread when 5% Karkade was blended with wheat flour.  相似文献   
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