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The seasonal change in petal color and pigmentation of 29 commercial Eustoma cultivars was studied. The flowers are basically divided into four groups according to the major anthocyanidin phenotype in association with petal coloration, i.e., delphinidin (Dp)-based (purple flower), cyanidin (Cy)-based (reddish purple flower), pelargonidin (Pg)-based (pink flower), and none (white flower) groups. The constitution of petal anthocyanidins was not changed by forcing treatment in most of the flowers. Lightness (L*) and chroma (C*, color saturation) showed a change along with the increase/decrease of hue angle difference (ΔH*), thus simultaneously the chromatic tonalities tended to move to redder and bluer, respectively. Floral pigment clustering described two flower groups in a dendrogram, based on anthocyanidin constitutions as phenetic markers, which are apparently the Dp- and Pg-based phenotypes of anthocyanidin syntheses. The Cy-based flowers made a subcluster with the Pg-based flowers, indicating a close relationship in the biosynthesis of the two anthocyanidins, and suggesting the Dp- and Pg-syntheses complement one another.  相似文献   
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The rumen microbiota comprises a vast range of bacterial taxa, which may affect the production of high-quality meat in Japanese Black cattle. The aim of this study was to identify core rumen microbiota in rumen fluid samples collected from 74 Japanese Black cattle raised under different dietary conditions using 16S rRNA gene amplicon sequencing. In the rumen of fattening Japanese Black cattle, 10 bacterial taxa, showing >1% average relative abundance and >95% prevalence, irrespective of the dietary conditions and the fattening periods, were identified as the core rumen bacterial taxa, which accounted for approximately 80% of the rumen microbiota in Japanese Black cattle. Additionally, population dynamics of the core rumen bacterial taxa revealed two distinct patterns: Prevotella spp. and unclassified Bacteroidales decreased in the mid-fattening period, whereas unclassified Clostridiales, unclassified Ruminococcaceae, Ruminococcus spp., and unclassified Christensenellaceae increased during the same period. Therefore, the present study reports the wide distribution of the core rumen bacterial taxa in Japanese Black cattle, and the complementary nature of the population dynamics of these core taxa, which may ensure stable rumen fermentation during the fattening period.  相似文献   
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Forest management and climate change may have a substantial impact on future soil organic carbon (SOC) stocks at the country scale. Potential SOC in Japanese forest soils was regionally estimated under nine forest managements and a climate change scenario using the CENTURY ecosystem model. Three rotations (30, 50, 100 yr) and three thinning regimes were tested: no‐thinning; 30% of the trees cut in the middle of the rotation (e.g. 15 year in a 30‐yr rotation) and thinned trees all left as litter or slash (ThinLef) and the trees from thinning removed from the forest (ThinRem). A climate change scenario was tested (ca. 3 °C increase in air temperature and 9% increase in precipitation). The model was run at 1 km resolution using climate, vegetation and soil databases. The estimated SOC stock ranged from 1600 to 1830 TgC (from 6800 to 7800 gC/m2), and the SOC stock was largest with the longest rotation and was largest under ThinLef with all three rotations. Despite an increase in net primary production, the SOC stock decreased by 5% under the climate change scenario.  相似文献   
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OBJECTIVE: To determine characteristics of power spectral analysis of heart rate variability (HRV) during a 24-hour period in dogs and to evaluate the effects of vagal and sympathetic tone on HRV ANIMALS: 16 healthy adult Beagles. PROCEDURE: Power spectral analysis of HRV was conducted, using 24-hour ambulatory ECG recordings. Circadian rhythms were evaluated in terms of absolute units of low-frequency (LF) and high-frequency (HF) powers, their ratio (LF:HF), and their adjusted (normalized) units (LF[norm] and HF[norm]). Three or 4 dogs were used for simultaneous measurement of heart rate and respiratory waveform as well as to evaluate treatment (propranolol, atropine, or both) administered to cause blockade of the autonomic nervous system. RESULTS: Values for LF and HF powers, LF:HF, LF(norm), and HF(norm) had obvious rhythmicity in clinically normal dogs. The HF power of HRV in dogs was extremely high, compared with that of other species, and HF peaks corresponded to peaks obtained from respiratory waveforms. Blockade of the autonomic nervous system documented that HRV in dogs was mostly attributable to vagal activity. CONCLUSION AND CLINICAL RELEVANCE: We determined characteristics of power spectral analysis of HRV in dogs, including circadian rhythm of the autonomic nervous system. Power spectral analysis of HRV may provide a useful noninvasive technique for assessing the effect of drugs on activity of the autonomic nervous system in dogs.  相似文献   
6.
Chromogranin A (CgA) is an acidic glycoprotein that is co-stored with hormones or neurotransmitters in granular components of endocrine cells and neurons, and released together with them in response to adequate stimulation. In addition to acting as a packaging protein, CgA functions as a precursor molecule that yields several bioactive peptides by proteolytic cleavage. The purpose of this study is to elucidate how different the processing of CgA is among endocrine tissues by immunostaining using multiple region-specific antisera, and to evaluate the availability of region-specific antisera. When various endocrine organs of rats were immunostained with four region-specific antisera against rat CgA (CgA 1-28, 94-130, 296-314, and 359-389), all amine/peptide-secreting endocrine tissues except the pineal body were stained positively. The adrenal medulla and gastric endocrine cells were equally intensely immunoreactive to all four antisera, while the other endocrine tissues, represented by pancreatic islets, showed different staining patterns depending on the antiserum. These results suggest that the processing of CgA differs from tissue to tissue. An antiserum against horse CgA 335-365, corresponding to rat CgA 359-389 which shows the highest concentration in the plasma and urine of the rat, again stained all endocrine tissues of the horse except the pineal body. Therefore, the anti-horse CgA 335-365 serum is useful for immunohistochemical survey of horse CgA, and may make possible the establishment of a CgA assay system for the measurement of CgA in the plasma, urine and saliva.  相似文献   
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The sensitivity to 18 antimicrobial drugs was examined for 66 strains of Ureaplasma sp isolated from respiratory tracts of calves suffering from enzootic pneumonia, urinary tracts of bulls and eyes of cows suffering from infectious bovine kerato-conjunctivitis. Furamizole, tiamulin fumarate, erythromycin lactobionate, malidomycin C, doxycycline hydrochloride, kitasamycin tartrate, tylosin tartrate, T-2636C, tetracycline hydrochloride, oxytetracycline hydrochloride, chlortetracycline hydrochloride, oleandomycin phosphate, furazolidone, spiramycin adipate, chloramphenicol and thiophenicol showed strong inhibiting activity on all the test strains. Among them, furamizole, tiamulin fumarate and erythromycin lactobionate were most active. Kanamycin sulphate showed weak activity on all the strains tested. The differences in origin of the test strains did not affect their sensitivity to any of the drugs.  相似文献   
10.
The effects of the medium (TCM 199 or SOFaa) and temperature (20 or 39 C) during meiotic arrest by cycloheximide (CHX) under air on the developmental competence of bovine oocytes after in vitro maturation (IVM) and fertilization (IVF) were investigated. Oocytes were maintained in meiotic arrest by 10 microg/ml CHX in a 50-microl droplet of 25-mM HEPES-buffered TCM 199 (H199) at 39 C or synthetic oviduct fluid (HSOFaa) at 20 or 39 C in air for 24 h. After release from the arrest, the oocytes was matured and fertilized in vitro and their developmental competence was examined. The developmental rate of oocytes arrested in HSOFaa at 20 C to the blastocyst stage was similar to that of non-arrested oocytes but was significantly higher (P<0.05) than that of oocytes arrested at 39 C in H199 or in HSOFaa. In consideration of oocyte transport conditions, we also investigated the meiotic arrest of oocytes maintained in a 0.25-ml straw by CHX individually with 10 microl HSOFaa or as a group (40-50 oocytes) with 170-200 microl HSOFaa at 20 C in air for 24 h. After release from meiotic arrest, the developmental competence of these oocytes was assessed similarly. The developmental rate of oocytes treated with CHX individually was similar to that of those treated with CHX in 50-microl droplet of HSOFaa at 20 C. However, the developmental rate of oocytes treated with CHX as a group was lower than that of oocytes treated with CHX in a 50-microl droplet. Five blastocysts developed from oocytes maintained in meiotic arrest in a plastic straw were transferred to five recipient heifers. Consequently, three recipients became pregnant and 2 calves were delivered. The results of the present study indicate that bovine oocytes treated with CHX in HSOFaa at 20 C under air retain the same developmental competence as non-arrested oocytes.  相似文献   
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