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71.
Soil and water pollution caused by organic waste is a concern for livestock-breeding areas. Nitrogen balance in a paddy-field water-purifying system in which cattle feces were applied was studied for 4 years to assess the suitability of the system for a subtropical area, Japan. Three successive harvestings using ratoon of forage rice following one rice transplanting were conducted with chemical fertilizer and high and low rates of cattle-feces application. Nitrogen load was 81.3–495.0 kg N ha?1 year?1, while nitrogen uptake was highly dependent on the yield of the first harvesting. Annual variation of forage rice yields was large, ranging from 15.5 to 26.8 Mg ha?1 owing to fluctuation in the yield at second and later harvestings. On average, nitrogen was lost by leaching at a rate of 2.3–3.4 kg N ha?1 year?1. The nitrogen content in soil at a depth of 0–5 cm increased up to 12.2 kg N ha?1 over the 4-year period compared with that before the field experiment. However, continuous application of cattle feces could slightly increase the nitrogen content in soil at a depth greater than 35 cm. Our results showed the ability of flooded forage rice to remove nitrogen at up to 320.1 kg ha?1 year?1 for a field to which cattle feces were applied. Further investigation is needed to produce a high and stable yield at second harvesting each year, to prevent the accumulation of soil nitrogen, and to assess gaseous nitrogen loss.  相似文献   
72.
The aim of the present study was to establish a simple method to monitor ovarian activity and non-invasively diagnose pregnancy in okapi (Okapia johnstoni). The feces of a female okapi were collected daily or every 3 days for 28 months. Steroids in lyophilized feces were extracted with 80% methanol, and the fecal levels of immunoreactive progestagens (progesterone and pregnanediol-glucuronide), androgen (testosterone), and estrogens (estradiol-17beta and estrone) were determined by enzyme immunoassays with commercially available antisera. Using the progesterone profiles, the durations of the luteal phase, follicular phase, and estrous cycle were determined to be 11.1 +/- 0.4, 5.3 +/- 0.6, and 16.5 +/- 0.7 days (n=22), respectively. Fecal levels of immunoreactive progesterone, pregnanediol glucuronide, and testosterone gradually increased from early pregnancy and peaked several months before parturition. More pregnanediol glucuronide was excreted in feces than progesterone during late pregnancy, but not during the estrous cycle. Although the fecal concentrations of immunoreactive estradiol-17beta and estrone change a little throughout pregnancy and non-pregnancy, they rose sharply and temporarily on the day following parturition. The present study indicates that fecal assays with commercial antisera for progesterone and pregnanediol glucuronide are useful for evaluating luteal activity and diagnosing pregnancy and indicates that estrogens might have some role as a trigger of parturition.  相似文献   
73.
Erect panicle rice cultivars utilize solar energy effectively and have improved ecological growing conditions. Among such cultivars, Shennong265 has been grown successfully throughout Northern China. Nevertheless, no studies have yet examined the relationships between crop dry matter productivity, weather conditions, and nitrogen uptake of the erect panicle type rice cultivar in Japan. The objective of our study was to evaluate the productivity of erect panicle rice Shennong265 in Western Japan under varied conditions. Three rice cultivars, Shennong265, Nipponbare, and Takanari were grown in the field under different fertilizer and plant density conditions in Western Japan; using this information, we compared yield and growth characteristics of Shennong265 with those of Nipponbare and Takanari. Although Shennong265 had radiation use efficiency similar to that of the high yielding cultivar (Takanari) and much higher leaf nitrogen content than Takanari and Nipponbare, the average grain yield of Shennong265 grown under normal fertilizer and plant density conditions was approximately 6.9 t ha?1 as against 6.2 t ha?1 for Nipponbare and 9.6 t ha?1 for Takanari. These results suggest that, while Shennong265 has a high yield potential, the environmental conditions including climate, fertilizer, and planting period provided in this study were not suitable for achieving its maximum yield. The reduced performance of Shennong265 may be caused by insufficient fertilizer after heading and by shorter growth periods, as well as by the climate of Western Japan. Additional fertilizer application during the heading stage and earlier transplanting may be needed to obtain higher Shennong265 yields in Western Japan.  相似文献   
74.
Paddy and Water Environment - Projection of future changes in agricultural water demand and supply through numerical model simulations can be one of the reference materials used for long-term rural...  相似文献   
75.
Paddy and Water Environment - We measured nutrient inflows and outflows on reclaimed land (157 km2, including 100 km2 of paddy fields) in Lake Hachiro. The net effluent loads...  相似文献   
76.
ObjectiveTo describe the hypnotic effects of a single bolus dose of propofol in Japanese macaques, and to develop a pharmacokinetic model.Study designProspective experimental trial.AnimalsFour male macaques (5-6 years old, 8.0-11.2 kg).MethodsThe macaque was restrained and 8 mg kg?1 of propofol was administrated intravenously at 6 mg kg?1 minute?1. Behavioural changes without stimuli (first experiment) then responses to external stimuli (the second experiment) were assessed every 2 minutes for 20 minutes. Venous blood samples were collected before and at 1, 5, 15, 30, 60, 120 and 210 minutes after drug administration, and plasma concentrations of propofol were measured (third experiment). Pharmacokinetic modelling was performed using NONMEM VI.ResultsMacaques were recumbent without voluntary movement for a mean 14.0 ± 2.7 SD (range 10.5-16.2) or 10.0 ± 3.4 (7.2-14.5) minutes and recovered to behave as pre-administration by 25.1 ± 3.6 (22.1-30.1) or 22.2 ± 1.5 (21.1-24.3) minutes after the end of propofol administration without or with stimuli, respectively. Respiratory and heart rates were stable throughout the experiments (28-68 breaths minute?1 and 72-144 beats minute?1, respectively). Our final pharmacokinetic model included three compartments and well described the plasma concentration of propofol. The population pharmacokinetic parameters were: V1 = 10.4 L, V2=8.38 L, V3=72.7 L, CL1= 0.442 L minute?1, CL2= 1.14 L minute?1, CL3= 0.313 L minute?1, (the volumes of distribution and the clearances for the central, rapid and slow peripheral compartments, respectively).ConclusionsIntravenous administration of propofol (8 mg kg?1) at 6 mg kg?1 minute?1 to Japanese macaques had a hypnotic effect lasting more than 7 minutes. A three-compartment model described propofol plasma concentrations over more than 3 hours.Clinical relevanceThe developed pharmacokinetic parameters may enable simulations of administration protocols to maintain adequate plasma concentration of propofol.  相似文献   
77.
The aim of this study was to identify factors that regulate ruminal epithelial insulin‐like growth factor‐binding protein (IGFBP) expression and determine its role in rumen epithelial cell proliferation. Primary bovine rumen epithelial cells (BREC) were incubated with short‐chain fatty acids (SCFAs) at pH 7.4 or 5.6, lactate, lipopolysaccharide (LPS), insulin‐like growth factor‐I (IGF‐I), ‐II (IGF‐II), or recombinant bovine IGFBP2 (rbIGFBP2). The mRNA expression levels of IGFBP in BREC were analyzed using quantitative real‐time polymerase chain reaction (qRT‐PCR). The proliferation rate of BREC was analyzed using a WST‐1 assay. IGFBP2 gene expression tended to be lower with SCFA treatment (p < .1), and IGFBP6 gene expression was significantly lower with SCFA treatment (p < .05). IGFBP3 and IGFBP6 gene expression tended to be higher with d ‐Lactate treatment (p < .1). IGFBP3 gene expression was significantly higher (p < .05) with LPS treatment. BREC treated with IGF‐I grew more rapidly than vehicle control‐treated cells (p < .01); however, recombinant bovine rbIGFBP2 inhibited IGF‐I‐induced proliferation. IGF‐II and/or rbIGFBP2 did not affect BREC proliferation. Taken together, SCFA treatment decreased IGFBP2 and IGFBP6 expression in rumen epithelial cells, and lower expression of these IGFBP might promote rumen epithelial cell proliferation by facilitating IGF‐I.  相似文献   
78.
The number of patients with chronic kidney disease (CKD) is growing continuously globally. In order to study pathogenesis and mechanisms, many animal models have been developed, including spontaneous, genetic, and induced models. Although each type of CKD shows disease-specific tissue changes in the early stages, tubular disorder and interstitial fibrosis histologically occur in the course of progression to end-stage renal failure. Therefore, the quantification of tubular disorder and interstitial fibrosis in CKD research using animal models is essential for measuring the degree of CKD severity and, thus, efficacy of therapeutic agents. Several strategies have been used to quantify interstitial fibrosis. Among scoring factors, renal tubular flattening can be quantitatively evaluated easily and inexpensively. However, the diagnostic value of renal tubular flattening evaluation has not been investigated previously. Therefore, in this study, we investigated the correlation between renal tubular flattening and interstitial fibrosis or renal tubular injury markers. We observed a strong correlation between the degree of tubular injury/interstitial fibrosis and renal tubular flattening in three types of mouse renal disease model. This is advantageous because rapidly advancing technologies such as artificial intelligence and image processing can be easily applied; hence, a more precise, objective, and quantitative diagnosis should be possible in the future.  相似文献   
79.
Cultivar tests under tropical environments could be an approach to explore soybean productivity under high temperature. Twenty-nine soybean cultivars divided into five groups with temperate origin (Japanese and US) and tropical origin (Indonesian-old, Indonesian-modern and other tropical) were grown for two years in a tropical environment at Banten, Indonesia, with minimal season-to-season variation in air temperature and day-length. Temperate cultivars were earlier in flowering and shorter in duration from R1 to R5. Temperate cultivars had a seed yield of 157 g m?2 (mean temperate cultivars) compared to 249 g m?2 (tropical cultivars), which was due to having lower values of pods, seed number and TDW. In addition, the occurrence of shriveling and smaller seed size compared to plants grown in their region of origin was considerably evident in Japanese cultivars. To account for the difference of growth duration, a maturity-corrected index for yield and relevant variables was calculated to consider the amount of incident solar radiation. The yield index for all tested cultivars ranged from .49 to 1.48, and Japanese cultivars showed the lowest yield index (.67), followed by US cultivars (.87), whereas tropical cultivars had index means from 1.05 to 1.20. Although they were both of temperate origin, Japanese cultivars tended to show a lower index than US cultivars. The tendency was similar for TDW and node number. The poor performance of temperate cultivars even after correction suggests that there is a genetic variation of adaptation to a tropical environment independent of growth duration. Additionally, there was considerable performance variation within temperate cultivars.  相似文献   
80.
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