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71.
Michiko NAKAI Manabu OZAWA Naoki MAEDOMARI Junko NOGUCHI Hiroyuki KANEKO Junya ITO Akira ONISHI Naomi KASHIWAZAKI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2014,60(3):256-259
In pigs, the embryonic developmental ability after intracytoplasmic sperm injection (ICSI) is inferior to that resulting from
in vitro fertilization (IVF). We evaluated the timing of cell division up to blastocyst formation on
embryonic development after ICSI using either whole sperm (w-ICSI) or the sperm head alone (h-ICSI) and IVF as a control. At
10 h after ICSI or IVF, we selected only zygotes, and each of the zygotes/embryos was evaluated for cleavage every 24 h until
168 h. We then observed a delay in the 1st and 2nd cleavages of h-ICSI embryos and also in blastocoele formation by w-ICSI
embryos in comparison with IVF embryos. The rate of blastocyst formation and the quality of blastocysts in both ICSI groups
were inferior to those in the IVF group. In conclusion, the delay in cleavage of porcine ICSI embryos shows poorer embryonic
development. 相似文献
72.
Yuri Hirayama Rie Takishita Hiroyasu Misawa Kazuhiro Kikuchi Koji Misumi Sachiko Egawa Sawako Motoyama Yasunobu Hasuta Yoshiyuki Nakamura Yutaka Hashiyada 《Animal Science Journal》2020,91(1)
This study aimed to compare the efficiency of non‐surgical embryo transfer (ET) using a newly developed catheter, which enables transferring embryos into a proximal site of the uterus (mostly uterine body), and surgical ET of vitrified porcine embryos. In Experiment 1, the catheter was inserted into 12 gilts, with each half of the group allocated to skilled or novice operators. The time required for insertion into the uterus did not differ between skilled and novice operators (4 min 9 s and 4 min 6 s, respectively). In Experiment 2, 12 gilts were used as recipients for non‐surgical and surgical ET with vitrified embryos (n = 6, each). There was no significant difference in the rate of piglet production based on the number of transferred embryos between surgical and non‐surgical ET (25.8% vs. 15.4%, p = .098). The results suggest that non‐surgical ET catheter allowed for easy insertion and transfer of embryos without special training. Although the catheter is effective for deposition of embryos into the proximal site of uterus, the efficiency of piglet production is not enhanced compared with surgical ET. The ET method using this catheter, being labor‐saving and less‐invasive, may contribute to the improvement of ET in pigs. 相似文献
73.
74.
Jozsef RáTKY Istvan EGERSZEGI Peter TOTH Soukanh KEONUCHAN Takashi NAGAI Kazuhiro KIKUCHI Noboru MANABE Klaus-Peter BRüSSOW 《The Journal of reproduction and development》2013,59(5):437-441
Worldwide, only a few “fatty” pig breeds exist with different and/or regional
utilization. Using the Hungarian Mangalica, which almost went extinct in Europe and the
Lao Moo Lat pig, which still has a large population in South-East Asia as exemples, we
wanted to demonstrate that indigenous (fatty) pig breeds may represent both national value
and tremendous economic potential. Since these less prolific and less productive breeds
cannot contribute to mass production, new market roles and methods should be established
for them in the premium segment of pork trading. Thus their preservation and propagation
needs the comprehensive collaboration of commercial, governmental actors and researchers.
Briefly summarizing the history, we report the current results of reproductive physiology
research. The commercial renaissance of Mangalica pigs is indebted to the enthusiastic
efforts of basic scientists, pig breeding experts and dedicated Mangalica producers.
Scientific achievements were applied to practical breeding and production of delicious
pork and processed products, which ultimately made the economic success in the Mangalica
sector possible. Both, research on and utilization of endangered (pig) breeds maintain not
only breed diversities, but also may improve the livelihood of farmers worldwide. 相似文献
75.
To investigate the role of polyamines in pre- and post-harvest fruit development of 'Akatsuki' peach (Prunus persica (L.) Batsch.) we measured polyamine concentrations, activities of polyamine biosynthetic enzymes and expression of genes encoding these enzymes. Concentrations of the free polyamines, putrescine (Put), spermidine (Spd) and spermine (Spm) in pre-harvest fruit peaked 16 days after full bloom (DAF) and then progressively decreased until harvest with the exception of Put, which showed a second peak at 94 DAF, just before the onset of ethylene production. In post-harvest fruit, minor changes in concentrations of Spd and Spm were observed, whereas Put concentration peaked on the harvest day, followed by an abrupt decrease and a subsequent 2-fold increase, which was opposite to the fluctuating pattern of ethylene production. Activities of arginine decarboxylase (ADC) and ornithine decarboxylase (ODC) peaked during the first stage of fruit development and then decreased until 80 DAF, after which the activities were below detection limits, suggesting that Put is synthesized during the early stage of fruit development. Activity of S-adenosylmethionine decarboxylase (SAMDC) decreased progressively until the end of S2. Expression levels of five putative polyamine biosynthetic genes, ADC, ODC, SAMDC, spermidine synthase (SPDS) and spermine synthase (SPMS), in pre-harvest and post-harvest fruit did not coincide precisely with the observed changes in enzymatic activities and polyamine concentrations. The possible role of polyamines during peach fruit development and the relationship between polyamines and ethylene biosynthesis are discussed. 相似文献
76.
Masayuki YAMAMOTO Hiroyasu MAKINO Tetsushi KAGAWA Osamu TOMINAGA 《Fisheries Science》2004,70(6):1089-1097
ABSTRACT: The occurrence and distribution of larval and juvenile Japanese flounder Paralichthys olivaceus and major demersal fish from May to September were examined at seven sandy beaches at the central Seto Inland Sea. The flounder appeared from late May to August and were mainly collected at a depth of 2–5 m. Settlement of larval flounder was seen from late May to late June. A total of 6412 individuals of 17 species representing 12 families were collected in the study area. The dominant fish species were Favonigobius gymnauchen (56.0%), Tarphops oligolepis (8.1%), Rudarius ercodes (7.8%), P. olivaceus (7.3%), Repomucenus spp. (7.0%) and Heteromycteris japonica (3.3%). The catches of flounder differed among beaches and months. The number of flounder in June at Ohama Beach, where the most flounder were collected, was 22.6 individuals per haul (400 m2 ). The density of the flounder correlated negatively to that of F. gymnauchen . 相似文献
77.
Hidetoshi Minamiyama Masafumi Shimizu Hitoshi Kunoh Tamotsu Furumai Yasuhiro Igarashi Hiroyasu Onaka Ryuji Yoshida 《Journal of General Plant Pathology》2003,69(1):65-70
An endophytic actinomycete, isolate R-5 of Streptomyces galbus Frommer, that has promising potential as a biocontrol agent was originally isolated from field-grown rhododendron. In this
study, the mode of entry of R-5 into leaves of tissue-cultured seedlings of rhododendron was investigated in connection with
its production of cell wall-degrading enzymes. Light and scanning electron microscopy (SEM) revealed that R-5 grew on leaf
surfaces and entered leaf tissues via stomata and that the internal mycelia grew out of stomata after colonization in host
tissues. Micromanipulation at the SEM level demonstrated a prominent depression in the host surface at the interfaces with
the mycelia, suggesting that such a depression could be caused by degradation of cell wall components by hydrolytic enzymes
secreted from R-5 mycelia. In subsequent plate assays, R-5 produced cellulase, pectinase, xylanase, and nonspecific esterase
when cultured in liquid medium. Moreover, R-5 multiplied in mineral medium containing cellulose, pectin, or xylan as a single
carbon source. Thus, R-5 mycelia could degrade host cell walls at contact sites and probably utilize the degradation products
as carbon sources.
Received: May 16, 2002 / Accepted: July 9, 2002 相似文献
78.
79.
Takayuki Kobayashi Hiroyasu Taguchi Mikiji Shigematsu Mitsuhiko Tanahashi 《Journal of Wood Science》2005,51(6):607-614
The consumption rates of three monolignols (p-coumaryl, coniferyl, and sinapyl alcohols) and eight analogues using horseradish peroxidase (HRP)–H2O2 as an oxidant were measured and compared with the anodic peak potentials thereof measured with cyclic voltammetry. 3-Monosubstituted
p-coumaryl alcohols, i.e., 3-methoxy-, 3-ethoxy-, 3-n-propoxy-, and 3-n-butoxy-p-coumaryl alcohols, had faster reaction rates than p-coumaryl alcohol. This is most probably due to the electron-donating effect of alkoxyl groups. However, the reaction rates
gradually decreased with an increase in the molecular weight of the alkoxyl groups. Furthermore, t-butoxyl group, which is a very bulky substituent, caused an extreme reduction in the reaction rate, even though its electron-donating
effect was almost the same as that of other alkoxyl groups. The reaction rates of 3,5-disubstituted p-coumaryl alcohols, especially 3,5-dimethyl-p-coumaryl alcohol, were very low compared with 3-monosubstituted p-coumaryl alcohols. These results suggest that there are three main factors of hindrance during the approach of monolignols
to the active site of HRP. First, from the results of 3-monoalkoxy-p-coumaryl alcohols, it was suggested that the volume of substituents could decrease their oxidation rates. Second, from the
results of 3,5-disubstituted p-coumaryl alcohols, it was suggested that local steric hindrance by the amino residues quite near the heme decreased the oxidation
rates. Third, from the results of the substrates with hydrophobic substituents at their 3,5-positions, we suggested that hydrophilicity
near heme would decrease their oxidation rates. 相似文献
80.
Mitsuo Matsumoto Hiroyasu Oka Yasushi Mitsuda Shoji Hashimoto Chihiro Kayo Yuko Tsunetsugu Mario Tonosaki 《Journal of Forest Research》2016,21(5):211-222
By considering trade-offs and complementarity between carbon removal from the atmosphere by forests and emission reduction by wood use, we developed a forest-sector carbon integrated model for Japan. We discuss mitigation measures for Japan based on model projections. The integrated model included the forest model and the wood use model. Based on three scenarios (baseline, moderate increase, and rapid increase) of harvesting and wood use, the integrated model projected mitigation effects including carbon removal by forests and emission reduction through the wider use of wood, until 2050. Results indicate that forests will not become a source of net carbon emissions under the three scenarios considered. The baseline scenario is most effective for mitigating climate change, for most periods. However, the sum total of carbon removal in forests and carbon emission reductions by wood use under the rapid increase scenario exceeded the one of the moderate increase scenario after 2043. This was because of strong mitigation activities: promoting replanting, using new high-yield varieties, and wood use. The results also indicated that increases in emission reduction due to greater wood use compensated for 67.9 % of the decrease of carbon removal in 2050, for the rapid increase scenario. The results show that carbon removal in forests is most important in the short term because of the relative youth of the planted forests in Japan, and that mitigation effects by material and energy substitution may become greater over the longer term. 相似文献