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461.
Summary A panel of twenty independently derived clones of man-mouse somatic cell hybrids isolated from fusions involving eight different parent cell combinations simultaneously analyzed for human chromosomes, citrate synthase, and a large number of other enzyme markers firmly or tentatively assigned to individual human chromosomes have provided direct evidence for a firm assignment of the structural gene coding for citrate synthase (CS) to human chromosome 12. 相似文献
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A smart nanocomposite adhesive was created to facilitate a simple production of long-persistent photoluminescent and hydrophobic commercial products. Even after being left in the dark for up to 90 min, the created photoluminescent adhesive agent continued to generate light. A surface-specific nanocomposite adhesive agent consisting of lanthanide-activated strontium aluminate (LSA) nanoparticles (NPs; 5–14 nm) immobilized in the environmentally friendly Arabic gum (AG) was developed. A light-transmitting nanocomposite adhesive agent was manufactured by dispersing LSA nanoparticles evenly across the AG matrix without agglomeration. An excitation peak at 365 nm and an emission wavelength at 519 nm were observed for the prepared adhesives at different concentrations of LSA NPs. The emission spectra showed either fluorescence or afterglow phosphorescence, depending on the LSA ratio. The photochromic transition from colourless to green beneath an ultraviolet (UV) lamp and greenish yellow in a dark room was tracked. The LSA NPs in the Arabic gum matrix imparted enhanced hydrophobicity and scratch resistance to the LSA@AG nanocomposite. The LSA@AG nanocomposite demonstrated excellent durability and photostability. This study confirmed that the mass production of smart adhesives for applications such as smart windows, smart packaging, and safety directional signs in buildings is possible. 相似文献
464.
AC Keebaugh ME Modi CE Barrett C Jin LJ Young 《Reproductive biology and endocrinology : RB&E》2012,10(1):54
ABSTRACT: BACKGROUND: The prairie vole (Microtus ochrogaster) is an emerging animal model for biomedical research because of its rich sociobehavioral repertoire. Recently, lentiviral transgenic technology has been used to introduce the gene encoding the green fluorescent protein (GFP) into the prairie vole germline. However, the efficiency of transgenesis in this species is limited by the inability to reliably produce large numbers of fertilized embryos. Here we examined several factors that may contribute to variability in superovulation success including, age and parentage of the female, and latency to mating after being placed with the male. METHODS: Females produced from 5 genetically distinct breeder lines were treated with 100 IU of pregnant mare serum gonadotrophin (PMSG) and immediately housed with a male separated by a perforated Plexiglas divider. Ovulation was induced 72 hr later with 30IU of human chorionic gonadotropin (hCG) and 2 hrs later mating was allowed. RESULTS: Superovulation was most efficient in young females. For example, females aged 6-11 weeks produced more embryos (14 +/- 1.4 embryos) as compared to females aged 12-20 weeks (4 +/- 1.6 embryos). Females aged 4-5 weeks did not produce embryos. Further, females that mated within 15 min of male exposure produced significantly more embryos than those that did not. Interestingly, there was a significant effect of parentage. For example, 12 out of 12 females from one breeder pair superovulated (defined as producing 5 or more embryos), while only 2 out of 10 females for other lines superovulated. CONCLUSIONS: The results of this work suggest that age and genetic background of the female are the most important factors contributing to superovulation success and that latency to mating is a good predictor of the number of embryos to be recovered. Surprisingly we found that cohabitation with the male prior to mating is not necessary for the recovery of embryos but is necessary to recover oocytes. This information will dramatically reduce the number of females required to generate embryos for transgenesis in this species. 相似文献