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171.
In June 2005, an outbreak of avian influenza (AI) caused by a low pathogenic H5N2 virus was identified in Japan. A serological surveillance was conducted because the infected chickens did not show any clinical signs. The Markov Chain Monte Carlo Method was used to evaluate the performances of serological HI and AGP tests because there was not enough time when the surveillance was initiated to conduct a test evaluation. The sensitivity of the AGP test (0.67) was lower than that of the HI test (0.99), while the specificities were high for both tests (0.96 for AGP and 0.90 for HI). Based on the low sensitivity of the AGP test, the HI test was used for primary screening in later stages of the epidemic.  相似文献   
172.
An 8-month-old thoroughbred colt presented with sudden onset right forelimb lameness. A radiographic series of the right carpus was performed, and it revealed a slab fracture of the fourth carpal bone and fracture of the proximal part of the third metacarpal bone. Arthroscopically guided repair of the slab fracture of the fourth carpal bone with a 3.5 mm cortex screw and lag screw fixation of the fracture of the proximal part of the third metacarpal bone were performed. The horse started to race at 32 months old and started in 65 races over three years without any trouble associated with the right carpus.  相似文献   
173.
We examined rodent dispersal of Dioscorea japonica bulbils. Bulbils dispersed by rodents may travel farther from their parent plants than those dispersed by gravity alone. To confirm the presence of secondary dispersal and the types of vector, we used an automatic camera to photograph animals that approached bulbils. To clarify secondary dispersal distance, we set marked bulbils at eight sites and searched for the bulbils once they were removed from their original locations by a disperser. We took photographs of mice (Apodemus speciosus) approaching the bulbils. In June, 10 of 333 bulbils that were moved germinated. We also measured the primary dispersal distance at four sites by dropping bulbils from heights of 0.5, 3.0, and 12.0 m. We then compared primary and secondary dispersal distances. The mean secondary dispersal distance was significantly greater than the primary dispersal distance for dispersal heights of 0.5 and 3.0 m, but less than that for a 12.0-m dispersal height. This indicates that rodents may disperse bulbils farther than gravity alone when bulbils drop from lower heights but they contribute little to dispersal for bulbils that drop from greater heights (e.g., from the top of the canopy). Thus, we confirmed the occurrence of rodent dispersal of bulbils and rodents might to some extent contribute to the dispersal and establishment of bulbils.  相似文献   
174.
We describe an automated gas sampling system for monitoring trace gas fluxes from soils. The sampling system allows automated collection of gas samples in glass vials using a syringe pump connected to an automated static chamber installed in the field. The gas samples are transferred to a laboratory and then analyzed using a gas chromatography system. Comparisons between manual and automated sampling of standard gases showed good agreement ( r 2 = 0.99996 for N2O, r 2 = 0.999 for CH4 and r 2 = 0.998 for CO2). In a field test, replicated flux measurements using two chambers generally showed good agreement. The sampling system allows frequent and long-term monitoring of fluxes under a wide range of weather conditions (tested temperatures ranged from –6.5 to 40°C; 127 mm day−1 max precipitation). The major advantages of the system are its increased portability, ease of operation and cost effectiveness compared with on-line automated sampling/analytical systems.  相似文献   
175.
Abstract

Phytoextraction using indica rice plants (Indian Rice Oryza ssp.) is a promising technique for remediating cadmium (Cd)-polluted paddy fields. Because this technique has only been established for paddy fields, we decided to examine phytoextraction in upland fields that have been converted from paddy fields. Although “CHOKOUKOKU” shows a shattering habit and lodging, its Cd uptake was significantly higher than that of other indica rice varieties. On the other hand, “IR8”, which was able to accumulate only moderate levels of Cd in its shoots, has a lodging tolerance, making it an optimal variety for southwest Japan, which experiences several typhoons each year. Therefore, both “CHOKOUKOKU” and “IR8” were useful in estimating practical phytoextraction in upland fields. A practical phytoextraction examination showed that the total Cd uptake of “CHOKOUKOKU” and “IR8” was 822 and 545 g ha?1, respectively, after a 4-year period. After phytoextraction by planting high Cd-accumulating rice plants, the Cd concentration of the plot soil decreased by approximately 35%, compared to the initial Cd concentration. To evaluate phytoextraction efficiency in the upland field, wheat (Triticum aestivum) was subsequently grown in the remediation field. The Cd concentration in the grains of “SHIROGANEKOMUGI” grown in the phytoextraction plot was lower than that grown in a non-phytoextraction plot; regrettably, it exceeded the Codex Alimentarius Commission standard, whereas the grain Cd concentrations of “CHUGOKU165” planted in phytoextraction plots complied with the Codex standard for wheat grain. These results suggest that phytoextraction using high Cd-accumulating rice varieties is a practical remediation system for low Cd-polluted upland fields. Moreover, we determined the end point of the phytoextraction process, which occurs when the soil Cd concentration of the phytoextraction fields is less than 0.6 mg kg?1 if “CHUGOKU165” is cultivated in this area.  相似文献   
176.
The c.1326T>G single nucleotide polymorphism (SNP) in the NCAPG gene, which leads to an amino acid change of Ile442 to Met442, was previously identified as a candidate causative variation for a bovine carcass weight quantitative trait loci (QTL) on chromosome 6, which was associated with linear skeletal measurement gains and daily body weight gain at puberty. Recently, we identified the stature quantitative trait nucleotides (QTNs) in the PLAG1‐CHCHD7 intergenic region as the causative variations for another carcass weight QTL on chromosome 14. This study aimed to compare the effects of the two QTL on growth and carcass traits using 768 Japanese Black steers from a progeny testing program and to determine whether a genetic interaction was present between them. The FJX_250879 SNP representing the stature QTL was associated with linear skeletal measurements and average daily body weight gain at early and late periods during adolescence. A genetic interaction between FJX_250879 and NCAPG c.1326T>G was detected only for body and rump lengths. Both were associated with increased carcass weight and Longissimus muscle area, and NCAPG c.1326T>G was also associated with reduced subcutaneous fat thickness and increased carcass yield estimate. These results will provide useful information to improve carcass weight in Japanese Black cattle.  相似文献   
177.
We collected fecal samples of white‐headed langurs from 3 of the 4 remaining habitat fragments (Fa, Fb and CZ) located in southwestern Guangxi, China in Nov 2005, and used 5 microsatellite loci and the SRY gene to assess the relatedness between 46 langurs within and between groups. We observed 2 forms of group structure: one‐male/multi‐female groups (OMGs) and all‐male groups (AMGs). One AMG in Fa was composed of 2 generations, included a father, 2 sons and 1 unrelated male, and all OMGs in all 3 habitats included 1 resident male, several adult females and offspring. Of the 21 identified father‐offspring cases, the resident male fathered 20 (95%) and the non‐resident male sired 1 (5%), suggesting that adult males had overwhelming priority of access to females as the resident male in an OMG, while the non‐resident male may also have the opportunity to adopt surreptitious mating strategies.  相似文献   
178.
ABSTRACT:   Carbon and nitrogen isotopic ratios in tissue of the bivalve corbicula ( Corbicula japonica ) and particulate organic matter (POM) were measured along a salinity gradient in the Kushida Estuary, Japan. The bivalve exhibited a gradual isotopic enrichment from the uppermost estuarine site (δ13C = −24.8‰ and δ15N = 8.6‰) to the marine site (δ13C = −16.1‰ and δ15N = 11.8‰). Using the concentration-weighted mixing model, the bivalves' food source is estimated from the isotope values for the bivalves and POM from terrestrial plants, marine phytoplankton and benthic microalgae. The results indicated that the contributions of benthic micro algae and phytoplankton were small, while terrestrial particulate matter is significantly important for the corbicula diet, although the contribution varies among sampling sites.  相似文献   
179.
To evaluate morphologic alterations in the thyroid gland in the second generation in cynomolgus monkeys, pregnant dams were exposed to high doses of thiamazole. In Experiment A, dams received thiamazole intragastrically via a nasogastric catheter from gestation day (GD) 50 to GD 150 or on the day before delivery. Initially, the dose level was 20 mg/kg/day (10 mg/kg twice daily); however, the dose level was subsequently decreased to 5 mg/kg/day (2.5 mg/kg twice daily), since deteriorated general conditions were observed in two dams. Six out of seven neonates died on the day of birth. The cause of neonatal death was tracheal compression and suffocation from goiter. The transplacental exposure to thiamazole affected the fetal thyroid glands and induced goiter in all neonates. The surviving neonate was necropsied 767 days after discontinuation of thiamazole exposure and showed reversibility of the induced changes. In Experiment B, dams were intragastrically administered thiamazole at 5 mg/kg/day (2.5 mg/kg twice daily) for treatment periods from GDs 51 to 70, 71 to 90, 91 to 110, 111 to 130 and 131 to 150. All fetuses showed enlarged thyroid glands but were viable. Histopathologically, hypertrophy and/or hyperplastic appearance of the follicular epithelium of the thyroid gland was observed at the end of each treatment period. The most active appearance of the follicular epithelium, consisting of crowded pedunculated structure, was demonstrated at end of the treatment period from GD 131 to 150. This is the first report on the morphology of fetal and neonatal goiter in the cynomolgus monkey.  相似文献   
180.
To clarify the morphological characteristics of the cynomolgus monkey immune system, we analyzed quantitative data on their lymphoid organs. Spleens, major lymph nodes and Peyer's patches were sampled from cynomolgus monkeys, and the lymphoid follicle and germinal center areas and percentages of CD3- and CD20-positive areas were calculated. All the organs analyzed showed large interindividual variations in the sizes of lymphoid follicles and germinal centers. Lymphoid follicle in the spleen, submandibular lymph nodes and Peyer's patches showed no marked difference in size. Germinal center size in the mesenteric lymph nodes and Peyer's patches were significantly smaller than those in the spleen. Areas containing T cells were largest in the lymph nodes, while those containing B cells were largest in the spleen and Peyer's patches. The mean size of the splenic lymphoid follicle in cynomolgus monkeys is larger than that in rats and similar to that in humans. Based on the large individual variation and the characteristics of lymphoid organs, it is important to use cynomolgus monkeys in standard toxicity studies. Taking advantage of the characteristics of each species enables reliable evaluation of the immunologic system in standard toxicity studies.  相似文献   
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