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排序方式: 共有1925条查询结果,搜索用时 93 毫秒
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Masahiro Sato Miyu Koriyama Satoshi Watanabe Masato Ohtsuka Takayuki Sakurai Emi Inada Issei Saitoh Shingo Nakamura Kazuchika Miyoshi 《International journal of molecular sciences》2015,16(8):17838-17856
Some reports demonstrated successful genome editing in pigs by one-step zygote microinjection of mRNA of CRISPR/Cas9-related components. Given the relatively long gestation periods and the high cost of housing, the establishment of a single blastocyst-based assay for rapid optimization of the above system is required. As a proof-of-concept, we attempted to disrupt a gene (GGTA1) encoding the α-1,3-galactosyltransferase that synthesizes the α-Gal epitope using parthenogenetically activated porcine oocytes. The lack of α-Gal epitope expression can be monitored by staining with fluorescently labeled isolectin BS-I-B4 (IB4), which binds specifically to the α-Gal epitope. When oocytes were injected with guide RNA specific to GGTA1 together with enhanced green fluorescent protein (EGFP) and human Cas9 mRNAs, 65% (24/37) of the developing blastocysts exhibited green fluorescence, although almost all (96%, 23/24) showed a mosaic fluorescent pattern. Staining with IB4 revealed that the green fluorescent area often had a reduced binding activity to IB4. Of the 16 samples tested, six (five fluorescent and one non-fluorescent blastocysts) had indel mutations, suggesting a correlation between EGFP expression and mutation induction. Furthermore, it is suggested that zygote microinjection of mRNAs might lead to the production of piglets with cells harboring various mutation types. 相似文献
3.
Tomoya Suzuki Kento Shiota Yu-ichiro Izato Masahiro Komori Koichi Sato Yasuyuki Takai Takayuki Ninomiya Atsumi Miyake 《International Journal of Hydrogen Energy》2021,46(11):8329-8343
Although hydrogen refueling stations (HRSs) are becoming widespread across Japan and are essential for the operation of fuel cell vehicles, they present potential hazards. A large number of accidents such as explosions or fires have been reported, rendering it necessary to conduct a number of qualitative and quantitative risk assessments for HRSs. Current safety codes and technical standards related to Japanese HRSs have been established based on the results of a qualitative risk assessment and quantitative effectiveness validation of safety measures over ten years ago. In the last decade, there has been much development in the technologies of the components or facilities used in domestic HRSs and much operational experience as well as knowledge to use hydrogen in HRSs safely have been gained through years of commercial operation. The purpose of the present study is to conduct a quantitative risk assessment (QRA) of the latest HRS model representing Japanese HRSs with the most current information and to identify the most significant scenarios that pose the greatest risks to the physical surroundings in the HRS model. The results of the QRA show that the risk contours of 10?3 and 10?4 per year were confined within the HRS boundaries, whereas the risk contours of 10?5 and 10?6 per year are still present outside the HRS. Comparing the breakdown of the individual risks (IRs) at the risk ranking points, we conclude that the risk of jet fire demonstrates the highest contribution to the risks at all of the risk ranking points and outside the station. To reduce these risks and confine the risk contour of 10?6 per year within the HRS boundaries, it is necessary to consider risk mitigation measures for jet fires. 相似文献
4.
Kawai S. Iwatsuki K. Suzuki K. Nishi S. Saruwatari M. Sato K. Wakita K. 《Electronics letters》1994,30(3):251-252
The authors demonstrate 10 Gbit/s optical soliton transmission in a recirculating loop through the use of a monolithically integrated MQW-DFB-LD/MQW-EA modulator light source. The timing jitter due to the Gordon-Haus effect is successfully reduced by the optical bandpass filters conventionally used in the cascaded EDFAs to avoid the accumulation of amplified spontaneous emission. The transmission distance of 7200 km is achieved at a bit error rate of 10-9 相似文献
5.
Takayuki Honma Yuichiro Kuroki Tomoichiro Okamoto Masasuke Takata Yukihiro Kanechika Masanobu Azuma Hitofumi Taniguchi 《Ceramics International》2008,34(4):943-946
Aluminum nitride ceramics were prepared by sintering with 0–4.8 mass% of Ca3Al2O6 (C3A) as a sintering additive. The transmittance in the range of 260–550 nm increased with increasing amount of C3A. The cathodoluminescence intensity attributed to oxygen-induced defects decreased with increasing amount of C3A. From the results, the increase of the transmittance in the range of 260–550 nm was considered to be related to the decrease of the oxygen-induced defect density. 相似文献
6.
Cell death was analyzed in neurulating mouse embryos after in vivo doses of 2-methoxyethanol (2-ME) that produce anterior neural tube defects. Characterization of 2-ME-induced cell death was performed by evaluating: (1) vital fluorochrome staining in whole embryos applying confocal laser scanning microscopy; (2) characteristics of cell debris in conventional histological sections revealed by light microscopy; and (3) Apoptag in situ immunohistochemical staining for apoptosis using light microscopy. Methods for quantification of cell death identified by these three techniques were explored using computerized image analysis. Physiological cell death in control embryos primarily occurred in the neural crest region during neural fold elevation. Embryos exposed to 2-ME had expanded areas of cell death in the neural crest and also new areas of cell death in medial regions of the anterior neural tube. Both physiological and 2-ME-induced embryonic cell death had morphological, immunohistochemical, and fluorochrome staining characteristics of apoptosis. When fluorescence data from confocal microscopic analysis of vital fluorochrome-stained embryos were analyzed, a dose-dependent increase was found in embryos exposed to 2-ME. Similar results were obtained when cell death was analyzed in either conventional histological sections or sections prepared for immunohistochemical detection of apoptosis. The cell death data obtained in this study correlate with previously observed near-term malformation rates, suggesting that a quantitative relationship exists between 2-ME-induced embryonic cell death and neural tube defects. 相似文献
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9.
T Hiroshima A Higashi T Imamoto S Kusumoto K Itakura K Nishijima K Nishi 《Canadian Metallurgical Quarterly》1996,116(12):951-960
We investigated whether a chemical assay by high-performance liquid chromatography (HPLC) as an alternative to the complicated and time-consuming bioassay for CS23 mutein of recombinant human basic fibroblast growth factor (rhbFGF-CS23) using the fetal bovine heart endothelial cell line ATCC CRL 1395. Physically, chemically or enzymatically denatured rhbFGF-CS23 was subjected to heparin affinity (HA)-HPLC and the bioassay. Good agreement was observed between the results obtained by these two methods. Moreover, HA-HPLC gave much more reproducible results (RSD = 1.9%, n = 6) than the bioassay (RSD = 7.4%, n = 18). HA-HPLC is therefore a simple, accurate and reproducible alternative to the bioassay for quality control and stability studies for rhbFGF-CS23 preparations. HA-HPLC is also considered to be applicable to assays for FGFs which have heparin affinity and biological activity similar to those of the CS23 mutein. 相似文献
10.
Fatemeh Niyati-Shirkhodaee Takayuki Shibamoto 《Journal of the American Oil Chemists' Society》1992,69(12):1254-1256
Formaldehyde, acrolein, malonaldehyde (MA), acetaldehyde and propanal produced from cod liver oil upon ultraviolet irradiation
(λmax=300 nm) were derivatized into nitrogenor sulfur-containing compounds and then analyzed by capillary gas chromatography with
a nitrogen-phosphorus detector or a flame photometric detector. Acrolein and MA were formed at levels of 10.9±3.06 and 190.2±38.4
nmol/mg of fish oil, respectively. Maximum levels of formaldehyde, acetaldehyde and propanal formed were 7.0±0.90, 49.1±4.5
and 35.8±4.0 nmol/mg of oil, respectively. Formation of propanal in large quantities corresponded to the high content of ɛ-3
fatty acids in cod liver oil. 相似文献