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1.
An electrofusion methodology for transferring meiosis-II chromosomes (M-II-t) has not been completely established. The present study compared the use of two temperatures (fusion at 37 C for Group A and 25 C for Group B) during an electrofusion procedure for mouse oocyte M-II-t and investigated the cytogenetic normality and developmental competence of embryos derived from in vitro fertilization using oocytes reconstructed by M-II-t. The M-II-t oocytes were fertilized in vitro and cultured to the blastocyst stage; the resultant embryos were analyzed cytogenetically. Subsequently, chromosomal normality of the resultant embryos at the prometaphase stage of first cleavage division and the integrity of the meiosis-II spindles of the reconstructed oocytes were analyzed. The success rate of electrofusion in Group B was 92.1%, which was significantly different from that in Group A (49.2%) (P<0.05). The fertilization rates (A, 80.7%; B, 77.2%) and development rates (A, 70.9%; B, 65.5%) in the M-II-t groups were significantly lower than those in the control group (95.0 and 92.2%, respectively) (P<0.05). The incidence of chromosomal abnormalities in the Group A embryos (20.5%) at the blastocyst stage was significantly higher than that in the control group embryos (8.5%) (P<0.05), but the incidence of chromosomal abnormalities in Group B (12.5%) was not significantly different compared with the other groups. A temperature of 25 C during the electrofusion procedure for M-II-t resulted in a good fusion rate, good development rate, and efficient production of chromosomally normal blastocysts. Furthermore, the incidence of chromosomal abnormalities in the first cleavage embryos at the prometaphase stage in Group B (9.6%) did not differ significantly from that in the control group (6.6%). The spindle morphology of the M-II-t oocytes in Group B was normal. 相似文献
2.
3.
Nitrous oxide (N2O) emission from flooded rice paddy fields was continuously measured by the closed chamber method at an experimental plot
in Thailand for a whole cultivation period. To characterize the N2O emission with regard to the denitrification N loss, the C2H2 inhibition method was applied. Flood water on the soil greatly suppressed the N2O emission. The N2O emission was mitigated considerably by even a thin film of the flood water. The overall average N2O emissions under flood conditions for one crop season (83 days) at the control site and the C2H2 treated site were 10.3 and 11.8 μg N m−2 h−1, respectively. The N2O emission from the C2H2 treated site was consistently higher than that from the control site and the N2O emission from both sites followed the same diurnal and seasonal variation pattern, indicating the effect of denitrification
inhibition by the supplied C2H2. The N2O emission enhanced along with temperature increase when NO3–N concentration in the soil water was above 0.4 mg N l−1 and soil temperature was above 24°C, suggesting specific temperature influence over the emission. The increase in NO3–N concentration and temperature in the soil affected only the N2O emission while the difference in the emission at the C2H2 treated site and the control site was not so much affected. It was suggested that most of the actively produced N2O under higher NO3–N concentration and temperature would likely to quickly emit to the atmosphere rather than to undergo further reduction to
N2. 相似文献
4.
We have evaluated four commercially available mold starters (SP-01, NY, M1, and “for kome miso”) for fermented fish pastes with the aim of determining the effect of different koji molds on the nutritional and sensory characteristics of the fermented product. Comparative studies among different fermented
fish and bean pastes were also conducted. Protein contents were considerably higher in the fermented fish pastes (22.7–24.1%)
than the fermented bean pastes (8.2–12.8%). Free amino acids, oligopeptides, organic acids, mineral content, and sensory scores
of the fermented fish pastes were superior to those of the bean pastes in terms of nutritional aspects. Sensory evaluation
of fermented fish and bean pastes clearly indicated that different koji molds used as starters had little effect on the taste of the fermented fish pastes. However, in terms of nutritional and
sensory characteristics, fermented fish pastes from trash fishes were found to be both commercially valuable and a potential
gain to food processing firms among the many new generic fermented food products becoming available. 相似文献
5.
Katsuya Obara Chizuka Obara Mitsuru Naito Ikki Mitsui Yumi Une Atsushi Asano Atsushi Tajima 《The Journal of Poultry Science》2022,59(2):168
This study examined the effects of calcium lactate on the development of chicken embryos in a shell-less culture system (cSLCS) up to the seventeenth day of incubation. In the presence of calcium lactate, a significant reduction in embryo viability was observed during the first week of incubation in cSLCS. On day 17 of embryo development, no significant difference was observed in the blood plasma calcium concentration or tibia bone density between cSLCS and intact control embryos, whereas the tibia length was significantly shorter in cSLCS embryos than in the intact control. These results suggest that calcium lactate supplementation in cSLCS supports bone formation in developing chicken embryos, but has adverse effects on the viability of embryos, particularly during the first week of embryo development. 相似文献
6.
Shingo Mitsui Sueo Aso Kiyoshi Tensho Kikuo Kumazawa 《Soil Science and Plant Nutrition》2013,59(1):17-18
The Foliar Uptake by Squash Plant The radioactive ash for experimental use, hereafter referred to as “Bikini ash”, was prepared by igniting the heavily contaminated substances on board No. 5 Fukuryu Maru at about 650°C, followed by sifting through a 100 mesh sieve. On ignition some parts of the fission products, particularly iodine, ruthenium and tellurium would have possibly been lost to the air. 相似文献
7.
Matsunaga T Harada T Mitsui T Inokuma M Hashimoto M Miyauchi M Murano H Shibutani Y 《American journal of veterinary research》2001,62(1):37-42
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
8.
lori INOUE Toshiaki OHARA Fumio NAMIKI Takashi TSUGE 《Journal of General Plant Pathology》2001,67(3):191-199
Restriction enzyme-mediated integration (REMI) mutagenesis was used to isolate mutants of Fusarium oxysporum f. sp. melonis impaired in pathogenicity. The race 2 strain Mel02010 was transformed with linearized pSH75, conferring resistance to hygromycin
B, with or without the enzyme used to linearize the plasmid. Addition of restriction enzymes did not affect the transformation
frequency. A total of 2929 REMI transformants were tested for pathogenicity to three melon cultivars, Amus, Ogon 9 and Ohi.
The race 2 strains are pathogenic to Amus and Ogon 9, but not to Ohi. Of 43 transformants with reduced pathogenicity on susceptible
melon cultivars, 12 mutants were examined in detail for pathogenicity, vegetative growth and integrative mode of pSH75. The
levels of pathogenicity varied among these mutants. Two mutants (B48 and B137) almost completely lost pathogenicity to both
susceptible cultivars, and the others had reduced pathogenicity. Mutants B48, B241, B886 and X36 were also impaired in vegetative
growth. Mutant B809 was a biotin auxotroph. By DNA gel blot analysis, nine mutants were found to contain a single copy of
the transformation vector. These mutants may thus be useful in isolating genes involved in pathogenicity.
Received 22 December 2000/ Accepted in revised form 16 April 2001 相似文献
9.
Sakai H Nakano H Yamaguchi R Yonemaru K Yanai T Masegi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(6):731-735
A new canine cell line, named CCT, was established from the cutaneous malignant histiocytosis in a 4-year-old male Borzoi. CCT proliferated with loose adherence and doubling time was approximately 30 hr. When co-cultured with latex beads, CCT phagocytized beads vigorously. Lysozyme and vimentin were positive by immunostaining, and non-specific esterase and acid phosphatase were positive by cytochemical staining. These features indicated the cells had a histiocytic nature. Furthermore, by subcutaneous injection to nude mice CCT could successfully form tumors with the morphological and immunohistochemical features similar to the original tumor. 相似文献
10.
Sawada Y Yanai T Nakagawa H Tsukamoto Y Tamagawa Y Yokoi S Yanagi M Toya T Sugizaki H Kato Y Shirakura H Watanabe T Yajima Y Kodama S Masui A 《Pest management science》2003,59(1):49-57
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species. 相似文献