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121.
选取超排后129S1/SvImJ品系小鼠的优质囊胚,使用辐照后冻存复苏的小鼠胚胎成纤维细胞作为饲养层,对比高浓度酶短时间消化法和低浓度酶长时间消化法,以0.25%胰酶-0.04%EDTA高浓度酶短时间消化法高效建立了4株小鼠胚胎干细胞系,建系率为36.31%.碱性磷酸酶,核型分析,体外分化和体内分化能力以及小鼠胚胎干细胞表面特异性分子标志0ct-4和Nanog的检测等表明,4个ES细胞系均为典型的小鼠胚胎干细胞系.所建立的ES细胞系为大规模培养ES细胞,进行后续的实验建立了理想的材料平台. 相似文献
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123.
Jerry Rhee Talisa Mohammad Nejad Olivier Comets Sean Flannery Eine Begum Gulsoy Philip Iannaccone Craig Foster 《Complexity》2015,20(3):22-38
Why do mouse corneal epithelial cells display spiraling patterns? We want to provide an explanation for this curious phenomenon by applying an idealized problem solving process. Specifically, we applied complementary line‐fitting methods to measure transgenic epithelial reporter expression arrangements displayed on three mature, live enucleated globes to clarify the problem. Two prominent logarithmic curves were discovered, one of which displayed the ? ratio, an indicator of an optimal configuration in phyllotactic systems. We then utilized two different computational approaches to expose our current understanding of the behavior. In one procedure, which involved an isotropic mechanics‐based finite element method, we successfully produced logarithmic spiral curves of maximum shear strain based pathlines but computed dimensions displayed pitch angles of 35° (? spiral is ~17°), which was altered when we fitted the model with published measurements of coarse collagen orientations. We then used model‐based reasoning in context of Peircean abduction to select a working hypothesis. Our work serves as a concise example of applying a scientific habit of mind and illustrates nuances of executing a common method to doing integrative science. © 2014 Wiley Periodicals, Inc. Complexity 20: 22–38, 2015 相似文献
124.
G. Mariani E. Benfenati R. Fanelli 《International journal of environmental analytical chemistry》2013,93(1-4):67-72
Abstract A mass spectrometric method in the negative ion chemical ionization mode was used to analyze α- and β-endosulfan in biological samples. The selected ion recording technique was employed, monitoring the ions at m/z 35 and 37. Biological samples of animals treated with endosulfan were analyzed. The method is selective and sensitive enough to analyze crude extracts of mouse brain and plasma directly without purification, since the chromatograms were clean 相似文献
125.
Mohammad Asadi Mehdi Ghahari Seyed A. Hassanzadeh-Tabrizi Amir M. Arabi Rozita Nasiri 《中国化学会会志》2020,67(5):720-731
Synthesis, characterization, and in vitro toxicity evaluation of upconversion luminescence NaLuF4:Yb3+/Tm3+ nanoparticles (UCLNPs) are reported in the current study. Initially, the synthesized lanthanide trifluoroacetate (Ln(OOCCF3)3) precursor was used to fabricate NaLuF4 nanoparticles doped with Yb3+ and Tm3+ metal ions. The nanoparticles were coated with calcium carbonate (CaCO3) after removing the hydrophobic species on them to enhance their biocompatibility. The in vitro methylthiazolyldiphenyl-tetrazoliumbromide (MTT) test was used to evaluate the toxicity of synthesized NaLuF4:Yb3+/Tm3+ nanoparticles (NLF-5) on L929 mouse fibroblast cell lines. The transmission electron microscopy image showed that the particle size of NaLuF4:Yb3+/Tm3+ was 32 nm. The synthesized NLF-5 nanoparticles have both α-cubic and β-hexagonal crystalline structures that provided a superb near-infrared-to-near-infrared upconversion luminescence signal when excited at 980 nm. MTT test results show that the death of L929 fibroblast cells was observed only at concentrations above 250 μg/mL of NaLuF4:Yb3+/Tm3+ nanoparticles. In addition, with an increase in patrol time of 24, 48, and 72 hr, cell toxicity increased significantly, while the coated nanoparticles did not have any toxic effects. The synthesized nanoparticles could be used as a suitable material for medical applications due to their small particle size, high photoluminescence emission intensity, and low toxicity. 相似文献
126.
Agnès Guillot Jean-Arcady Meyer 《Nonlinear dynamics, psychology, and life sciences》2000,4(4):297-309
In previous papers, we have established, through a functional analysis of the behavioral sequences recorded on laboratory mice over a twelve-hour period, the existence of two independent strategies of action selection. On the one hand, the choice of ultradian alternations of rest and activity bouts makes it possible for every mouse to maximize its net energy gain over a one-day or a one-night interval. On the other hand, the succession of acts performed within an activity bout might serve to precisely fit the metabolic needs of each animal, because the corresponding results present great inter-individual variability, with some mice increasing and others decreasing their net energy gain. To determine what kind of dynamic system could generate these successions of acts within an activity bout, we performed a nonlinear time series analysis of the energy costs related to the acts displayed by the mice during such a period. The results suggest that chaotic dynamics might be involved in action selection in mice. Thus, the variability mentioned above could be a consequence of the sensitive dependence on initial conditions associated with such dynamics, and would allow mice to rapidly adapt their metabolic needs to the ongoing situation. 相似文献
127.
The possibilities with which an optical mouse can be applied to obtain scientific measurements are currently limited by the maximum distance possible between the mouse and surface under interrogation. We demonstrate that a simply adapted optical mouse is able to operate as a recording instrument in the digital speckle correlation mode; wherein greater distances between optical mouse and translating surface are possible. Linear (R2 > 0.98) and repeatable measurements in the x and y axis were obtained with the optical mouse and translating surface separated at 300 mm. In both cases, the measurement resolution was 0.025 mm. Digital speckle correlation with an optical mouse offers the ability to obtain measurements of displacement and deformation at a fraction of the investment in time and cost of conventional setups. 相似文献
128.
本实验比较了昆明白小鼠与F_1代杂交鼠(昆明白×BALB/c)的排卵数、怀孕率、百枚卵产仔数.经统计分析,F_1代杂交鼠的平均排卵数、怀孕率、百枚卵产仔数均极显著的高于昆明白小鼠. 相似文献
129.
Yan Zhao Hui Kong Ye Sun Huibin Feng Yue Zhang Xin Su Huihua Qu Qingguo Wang 《Biomedical chromatography : BMC》2014,28(12):1864-1868
An indirect competitive enzyme‐linked immunosorbent assay (icELISA) based on monoclonal antibaodies (MAb) was recently developed. This new method displays high sensitivity and accuracy, and is especially suitable for pharmacokinetic studies in small laboratory animals. This study aimed to develop an icELISA procedure for baicalin (BAL) quantitation in blood. We successfully developed the icELISA and applied in pharmacokinetic assays of Gegen Qinlian Decoction in mice. A linear correlation was obtained for BAL concentrations in the range from 34.69 to 2220.00 µg/L. The regression equation was y = 1.5557 ? 0.4028log(C) with a correlation coefficient of 0.9936. Precision and accuracy of the icELISA method were evaluated by the variations between replicates from well to well (intra‐assay) and plate to plate (inter‐assay). The values obtained for these parameters were within the normal range (<15%). The recovery rates ranged from 98.93 to 126.78%, meeting the requirements for biological samples. Stability studies showed that BAL sample solutions were intact for 1 h, enough time for UV detection. However, long‐term storage and especially freeze–thaw procedures were detrimental to BAL. The pharmacokinetic parameters derived from mouse experiments were as follows: area under the curves from time 0 to 48 h, 1876.15 ± 1108.14 mg h/L; mean maximum blood concentrations, 101.09 ± 31.53 mg/L; time of maximum concentration, 3.58 ± 2.88 h; mean residence time, 79.30 ± 61.21 h. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
130.
《Biomedical chromatography : BMC》2017,31(7)
A sensitive and rapid LC–MS/MS method was developed and validated for the simultaneous quantitation of four HDAC inhibitors, namely belinostat (BST), panobinostat (PST), rocilinostat (RST) and vorinostat (VST), in mouse plasma as per regulatory guidelines. The analytes and internal standard were extracted from 50 μL mouse plasma by protein precipitation, followed by chromatographic separation using an Atlantis C18 column with an isocratic mobile phase comprising 0.1% formic acid–acetonitrile (25:75, v /v) at a flow rate of 0.5 mL/min within 2.5 min. Detection and quantitation were done by multiple reaction monitoring on a triple quadrupole mass spectrometer following the transitions: m/z 319 → 93, 350 → 158, 434 → 274 and 265 → 232 for BST, PST, RST and VST, respectively, in the positive ionization mode. The calibration curves were linear from 2.92 to 2921 ng/mL for BST and PST and from 1.01 to 1008 ng/mL for RST and VST with r 2 ≥ 0.99 for all of the analytes. The intra‐ and inter‐batch accuracy and precision (CV) across quality controls varied from 85.5 to 112% and from 2.30 to 12.5, respectively, for all of the analytes. Analytes were found to be stable under different stability conditions. The method was applied to an i.v. pharmacokinetic study in mice. 相似文献