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排序方式: 共有988条查询结果,搜索用时 15 毫秒
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985.
Hidetoshi Ishibashi Hideyuki H. Motohashi Mami Kumon Kazuhiro Yamamoto Hironori Okada Takashi Okada Kazuhiko Seki 《Reproductive biology》2013,13(2):139-144
Experimental primate embryology has been hampered by limited access to embryos. In addition to surgical techniques, the less stressful non-surgical technique of uterine flushing has been developed but has had only limitedly used in recovering pre-implantation embryos from marmoset monkeys. In this study, we introduce the use of ultrasonography during marmoset non-surgical uterine flushing to make the cannulation easier, to further reduce stress, and to ensure thorough uterine flushing. We were able to cannulate in 99% of the transcervical cannulation attempts, repeat the flushing up to 17 times with the same animal, and recover up to 90% of the ovulation products. We also found that 8-cell or earlier stage embryos could be frequently obtained by non-surgical uterine flushing at 4 or 5 days after ovulation. The easiness and effectiveness of this novel ultrasound-guided technique will enable more research groups to study marmoset embryology and facilitate progress in this field. 相似文献
986.
Kohtaro Kirimura Satoshi Fukuda Hidetoshi Abe Shinji Kanayama Shoji Usami 《FEMS microbiology letters》1992,90(3):235-238
Abstract The mitochondrial DNA was isolated from Aspergillus niger WU-2223L, a citric acid-production strain, and characterized by restriction-endonuclease mapping. Cloned fragments which covered the total range of the mitochondrial DNA were assembled and utilized to construct the restriction-endonuclease map for nine restriction enzymes. This map showed that the mitochondrial DNA was a circular molecule of 32.6 kb. 相似文献
987.
Noboru Oriuchi Naoyuki Watanabe Hidetoshi Kanda Makoto Hashimoto Sumio Sugiyama Seiichi Takenoshita Kyouichi Imai Ryuzou Ueda K. Endo 《Cancer immunology, immunotherapy : CII》1998,46(6):311-317
The study was designed to clarify the difference in pharmacokinetics of monoclonal antibodies (mAb) in animal models and
humans, and to elucidate the applicability of animal models. 99mTc-labeled murine mAb – against carcinoembryonic antigen (designated BW431/26), and neural cell adhesion molecule (NE150)
– and one chimeric mouse/human mAb against nonspecific cross-reacting antigen (chNCA) were administered i.v. to normal mice
and athymic mice (370 kBq, 400 ng) xenografted with human cancer cells expressing antigens, and into patients with tumor (925
MBq, 1 mg). The biodistribution of two of the three mAb (not 99mTc-BW431/26) differed clearly in mice and patients. 99mTc-NE150 showed specific uptake in xenografted tumor and otherwise a normal biodistribution; however, clinical examination
showed increased uptake in the liver with rapid blood clearance (mean α half-life = 31.1 min) compared with 99mTc-BW431/26 (28.4 h). 99mTc-chNCA demonstrated increased blood clearance and renal excretion in both normal and athymic mice, with accumulation in
tumors. Clinical examination showed rapid blood clearance (mean α half-life = 6.4 min) and increased uptake in the liver.
High-performance liquid chromatographic analysis of 99mTc-chNCA revealed the immune complex in blood, suggesting uptake of the complex by the reticuloendothelial cells. The biodistribution
of radiolabeled mAb in animal and human models was variable and specific for each of the three mAb. The results of animal
studies with mAb should be evaluated carefully before being extrapolated to humans, on the basis of the nature of the mAb
and interacting substances.
Received: 9 April 1997 / Accepted 3 March 1998 相似文献
988.
Preferential attachment is a stochastic process that has been proposed to explain certain topological features characteristic of complex networks from diverse domains. The systematic investigation of preferential attachment is an important area of research in network science, not only for the theoretical matter of verifying whether this hypothesized process is operative in real-world networks, but also for the practical insights that follow from knowledge of its functional form. Here we describe a maximum likelihood based estimation method for the measurement of preferential attachment in temporal complex networks. We call the method PAFit, and implement it in an R package of the same name. PAFit constitutes an advance over previous methods primarily because we based it on a nonparametric statistical framework that enables attachment kernel estimation free of any assumptions about its functional form. We show this results in PAFit outperforming the popular methods of Jeong and Newman in Monte Carlo simulations. What is more, we found that the application of PAFit to a publically available Flickr social network dataset yielded clear evidence for a deviation of the attachment kernel from the popularly assumed log-linear form. Independent of our main work, we provide a correction to a consequential error in Newman’s original method which had evidently gone unnoticed since its publication over a decade ago. 相似文献