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91.
A study was conducted to investigate whether ovulation in gilts could be synchronized for embryo collection by the administration of estradiol benzoate (EB) or estradiol dipropionate (EDP) to induce pseudopregnancy, followed by the treatment with prostaglandin F (PGF) on 10 days after. Ten gilts each received a total of 20 mg of EB or EDP on Day 10 or EB on Day 10 and 14 to induce pseudopregnancy (Day 0 = onset of estrus). Donors received PGF 10 or 15 days (as a control) after the first administration of estrogens and subsequently eCG and hCG, and were then inseminated artificially. The embryos were collected 7 days after the administration of hCG, and assessed for embryo yield and their developmental stages. All protocols resulted in good embryo yield (9.8–13.2 embryos in average), and the embryos showed average ability to develop to the expanded blastocyst stage (3.29–4.03 as developmental scores) without any significant differences among the protocols. These results suggest that the administration of PGF 10 days after the treatment of gilts with EB or EDP would allow synchronization of ovulation and embryo collection, as well as shortening the period from estrus detection to embryo collection, thus improving embryo collection efficiency.  相似文献   
92.
Male pronucleus (MPN) formation is a very important physiological event during fertilization, which affects in vitro production of transferrable embryos. The aim of this study was to find out the correlation between the number of penetrated sperm and the occurrence of failure of MPN formation in porcine oocytes. In vitro matured porcine oocytes were fertilized in vitro with frozen epididymal sperm. Two different frozen sperm lots were tested in this study, which were different in terms of polyspermy rates. The numbers and the status of penetrated sperm in oocytes were evaluated 10 h after insemination. Under high polyspermy condition, the polyspermy rate was 83.5% with an average mean of 3.5 sperms per penetrated oocyte, whereas the percentage of polyspermy was 65.5% with an average mean of 2.4 sperms per penetrated oocyte under moderate polyspermic condition. Correlation analysis revealed a negative correlation between the number of penetrated sperm and their MPN formation percentage both in the sperm lot of high polyspermy (R = −0.560, p < 0.05) and in the sperm lot of moderate polyspermy (R = −0.405, p < 0.05) which suggests that penetration of excessive spermatozoa disables the oocyte cytoplasm to promote MPN formation.  相似文献   
93.
We isolated a novel Arabidopsis thaliana mutant line that requires high levels of boron (B) for normal growth. Line 8–21 was identified from ethyl methanesulfonate-mutagenized M2 population. When grown in medium containing 3 μm or less B in the form of boric acid, the fresh weights of aerial portions of the mutant were about a half of those of the wild type, but in that containing 300 μm B, the growth appeared normal. The mutant plants did not shown any difference in root growth from the wild-type plants in the range of B concentrations tested. When grown with 30 μm B, the B concentration in shoots of the line 8–21 was similar to that in the wild-type, suggesting that the mutant could not utilize B efficiently. Line 8–21 was not allelic to bor1-1 (Noguchi et al., Plant Physiol., 115, 901–906, 1997). A significant portion of F2 plants from the crosses between the wild-type and the mutant grew poorly on a low B media, suggesting segregation of the mutation.  相似文献   
94.
Absorption and metabolism of a natural compound, 6-O-caffeoylsophorose (CS) from acylated anthocyanins in a red vinegar fermented with purple sweet potato, were clarified. The absorption of CS and conjugated CS in blood from orally administrated Sprague-Dawley rats at a dose of 400 mg/kg was investigated by electrochemical detection-high performance liquid chromatography. As a result, CS was successfully detected in rat plasma (AUC(0-6h), 108.6 ± 8.1 nmol h/mL) and was found to be an intact absorbable polyphenol. In addition, half of the absorbed CS was detected as its conjugates (AUC(0-6h), 50.7 ± 5.7 nmol h/mL) as well as caffeic and ferulic acids from CS. By a time-of-flight-mass spectrometric analysis of CS-administered plasma sample, glucuronide and methylated conjugates of CS were identified, in addition to glucuronide, methylated, or sulfate conjugates of caffeic and ferulic acids. Consequently, CS was absorbed in intact form into rat blood and partly degraded to caffeic and ferulic acids or metabolized by glucuronidation, methylation, or sulfatation.  相似文献   
95.
Heterogeneity in the expression of tumor-associated antigens, as defined by the binding of monoclonal antibodies, is a characteristic common to most, if not all, human carcinoma cell populations. Antigen-negative cells within the population can escape detection and therapy by their failure to bind the appropriate antibody. Therefore, the extent of antigenic heterogeneity is an important consideration when designing protocols for the management of cancer by administration of monoclonal antibodies. One approach to counteracting the effect of antigenic heterogeneity is the use of clone A of recombinant human leukocyte interferon (Hu-IFN-alpha A). Administration of Hu-IFN-alpha A in vivo effectively increased the amount of tumor antigen expressed by a human colon xenograft in situ and augmented the localization of a radiolabeled monoclonal antibody to the tumor site. Concomitant administration of Hu-IFN-alpha A and monoclonal antibody may thus be effective in overcoming the antigenic heterogeneity of carcinoma cell populations and in enhancing the efficacy of monoclonal antibodies in the detection and treatment of carcinoma lesions.  相似文献   
96.
High-resolution electron microscopy and lithium-7 nuclear magnetic resonance measurements were carried out for a disordered carbon material, prepared by heat treatment of polyphenylene, in which lithium was stored electrochemically. The nuclear magnetic resonance spectrum suggests the existence of Li(2) covalent molecules in the carbon material. This extra covalent site of lithium storage promises extraordinarily high energy density for secondary batteries.  相似文献   
97.
Journal of Soils and Sediments - To restore the disaster resilience of coastal forests in tsunami-prone areas, growing bases have been artificially constructed with embanking before afforestation...  相似文献   
98.
We have many studies (1, 2) on the growing process of sugar beets. The results 3) of the examinations in the past have hown that among the three clements nitrogen tas the greatest influence on the growth and ield. Therefore many studies (4, 5) of nutrient metabolism arc carried out laying tress on nitrogen.  相似文献   
99.
Collection efficacy and in vitro embryo developmental ability of oocytes obtained from Duroc‐breed ovary donors at different stages of the estrous cycle (days 6, 12 and 16 after estrus) were performed. The numbers of collected oocytes did not differ significantly among the different estrous cycle groups (total 72–90 oocytes per gilt). However, the blastocyst rates of oocytes collected on days 12 and 16 (9.2% and 19.4%, respectively) were significantly higher than those on day 6 (1.1%). More oocytes were obtained on day 16 from small follicles (<2 mm in diameter; 85.3 oocytes per gilt) than from medium‐sized (≥2–<6 mm) and large (≥6 mm) follicles (17.5 and 12.8 oocytes, respectively). The blastocyst rates in both the medium‐sized and large follicle groups (20.0% and 19.2%, respectively) were significantly higher than that in the small follicle group (6.3%). The blastocyst cell numbers in both the medium‐sized and large follicle groups (39.4 and 43.3 cells, respectively) were significantly higher than that in the small follicle group (30.6 cells). The results suggest that oocyte collection from cycling Duroc pigs can be carried out efficiently from the late luteal to follicular stage. Those oocytes collected from medium‐sized and large follicles show better embryo development.  相似文献   
100.
This paper describes an attempt to estimate the mass budget of irrigation ponds within a watershed and the possibilities to control the effluent load of nutrients from the watershed located in the Kyotanabe area. The paddy field lots were irrigated by the ponds and several mountain streams. In the study watershed, there were two ponds located on the upper and lower sides of a paddy area. Water could be pumped up from the lower pond to the upper pond as necessary. At the ponds, the total amount of nitrogen and phosphorus in the inflow loads including the sediment release was larger than those in the outflow loads. In SS, the effect of load reduction in the ponds was high. It is assumed that organic load reduction was not expected in the ponds. The study result indicates that it is possible to remove the nutrients in the ponds when a larger amount of water is pumped up than when the ponds are only in irrigation use. Moreover, the removal capacities of the nutrients could probably be increased in both ponds by controlling the amount of sediment releases. Electronic Publication  相似文献   
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