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71.
72.
To preserve Jeju black cattle (JBC; endangered native Korean cattle), a pair of cattle, namely a post-death cloned JBC bull and cow, were produced by somatic cell nuclear transfer (SCNT) in a previous study. In the present study, we examined the in vitro fertilization and reproductive potentials of these post-death cloned animals. Sperm motility, in vitro fertilization and developmental capacity were examined in a post-death cloned bull (Heuk Oll Dolee) and an extinct nuclear donor bull (BK94-13). We assessed reproductive ability in another post-death cloned cow (Heuk Woo Sunee) using cloned sperm for artificial insemination (AI). There were no differences in sperm motility or developmental potential of in vitro fertilized embryos between the post-death cloned bull and its extinct nuclear donor bull; however, the embryo development ratio was slightly higher in the cloned sperm group than in the nuclear donor sperm group. After one attempt at AI, the post-death cloned JBC cow became pregnant, and gestation proceeded normally until day 287. From this post-death cloned sire and dam, a JBC male calf (Heuk Woo Dolee) was delivered naturally (weight, 25 kg). The genetic paternity/maternity of the cloned JBC bull and cow with regard to their offspring was confirmed using International Society for Animal Genetics standard microsatellite markers. Presently, Heuk Woo Dolee is 5 months of age and growing normally. In addition, there were no significant differences in blood chemistry among the post-death cloned JBC bull, the cow, their offspring and cattle bred by AI. This is the first report showing that a pair of cattle, namely, a post-death cloned JBC bull and cow, had normal fertility. Therefore, SCNT can be used effectively to increase the population of endangered JBC.  相似文献   
73.
Due to global climate change, Korea is facing severe droughts that affect the planting and early vegetative periods of upland crops. Soybean and adzuki bean are important legume crops in Korea, so it is critical to understand their adaptations to water stress. This study investigated the changes in root morphological properties in soybean and adzuki bean and quantified the findings using fractal analysis. The experiment was performed at the National Institute of Crop Science in Miryang, Korea. Soybeans and adzuki beans were planted in test boxes and grown for 30 days. The boxes were filled with bed soil with various soil moisture treatments. Root images were obtained and scanned every two days, and the root properties were characterized by root length, depth and surface area, number of roots, and fractal parameters(fractal dimension and lacunarity). Root depth, length and surface area and the number of roots increased in both crops as the soil moisture content increased. The fractal dimension and lacunarity values increased as the soil moisture content increased. These results indicated that the greater the soil moisture, the more heterogeneous the root structure. Correlation analysis of the morphological properties and fractal parameters indicated that soybean and adzuki bean had different root structure developments. Both soybean and adzuki bean were sensitive to the amount of soil moisture in the early vegetative stage. Soybean required a soil moisture content greater than 70% of the field capacity to develop a full root structure, while adzuki bean required 100% of the field capacity. These results would be useful in understanding the responses of soybean and adzuki bean to water stress and managing irrigation during cultivation.  相似文献   
74.
Sericite is mica-based natural clay that is annealed at 800 ℃ for 4 h, followed by acid activation using 3.0 mol L-1HCl at 100℃. The interaction of cesium(I), Cs(I), with sericite could provide useful data for the study of soil erosion or mass water movement utilizing the natural radioactive Cs. In this study sericite and activated sericite were used to assess their suitability in the attenuation of Cs from the aquatic environment under both batch and column experiments. The surface morphological studies indicated that a disordered and heterogeneous surface structure was exhibited by the activated sericite, whereas the native sericite exhibited a compact and layered structure. The Brunauer-Emmett-Teller(BET) specific surface area results indicated a significant increase in the surface area due to the activation of sericite. The batch reactor data collected for various parametric studies revealed that an increase in p H(from 2.0 to 8.0) and sorbate concentration(from 10.0 to 100.0 mg L-1) apparently favored the attenuation of Cs(I). The timedependent sorption data revealed that Cs(I) uptake was very rapid, and it achieved its saturation value within just 50 min of contact.The kinetic modeling studies indicated that the uptake of Cs(I) followed a pseudo-second-order rate equation; hence, the attenuation capacity of these solids for Cs(I) was estimated to be 0.858 and 4.353 mg g-1for sericite and activated sericite solids, respectively.The adsorption isotherm modeling data showed a reasonably good applicability of the Freundlich model than the Langmuir model.The effect of background electrolyte concentrations(0.001 to 0.1 mol L-1) of Mg(NO3)2indicated that the presence of this electrolyte could not significantly affect the percent removal of Cs(I) by activated sericite. Furthermore, the fixed-bed column reactor operations were performed to obtain the breakthrough data, which were fitted well to the Thomas non-linear equation. Therefore, the loading capacity of Cs(I) was estimated to be 1.585 mg g-1at the initial influent Cs(I) concentration of 30.0 mg L-1at p H 5.0.  相似文献   
75.
A true diaphragmatic hernia is a congenital diaphragmatic malformation that can appear identical to a peritoneopericardial diaphragmatic hernia (PPDH). True diaphragmatic hernias are rare in dogs. Herein we describe the use of positive contrast peritoneography for diagnosis of a true diaphragmatic hernia in two dogs.  相似文献   
76.
Abstract. Treatment of rainbow trout macrophages with glycyrrhizin (GL), an aqueous extract of licorice, Glycyrrhiza glabra , enhanced their respiratory burst activity. Maximal effects were seen using concentrations of 10–100 μml−1. GL also modulated trout lymphocytes, increasing proliferation responses to the mitogen phytohaemagglutinin some two-fold over a range of GL concentrations. In addition, GL elicited the release of a macrophage activating factor (MAF) from head kidney leucocytes, as assessed by the ability of generated supernatants to increase respiratory burst activity of target macrophages. MAF activity was most apparent using 100 μg ml−1 GL to induce MAF release and a 48-h incubation period with the target macrophages. Finally, GL was shown to enhance the release of MAF in response to the mitogen concanavalin A. The possible use of GL as a stimulant of fish innate defences is discussed.  相似文献   
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