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1.
<正>随着现代科技的发展,实验室自动化分析仪越来越普遍。UF-50尿沉渣分析仪检测仪是对尿液直接做荧光色素染色,利用流式细胞仪和电阻抗的原理,以激光散射强度,散射波幅度和荧光波幅度的技术。识别和计数尿中红细胞、白细胞、上 相似文献
2.
陡脉冲电场对荷瘤BALB/c小鼠癌细胞杀伤效应的实验研究 总被引:1,自引:0,他引:1
观测陡脉冲电场对荷瘤BALB/c小鼠癌细胞的杀伤效应。处理后的癌细胞在光镜下表现为细胞核固缩、核碎裂、核溶解;在电镜下表现为异染色质增加,边集,呈团块样改变,细胞质肿胀,脂滴数量增加,质膜破裂;核固缩,碎裂,线粒体肿胀。实验揭示了陡脉冲电场能有效地杀伤癌细胞,明显抑制了荷瘤小鼠恶性肿瘤的生长、增殖,有着良好的应用前景。 相似文献
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Kh. Ya. Karimov B. U. Iriskulov M. K. Ergashev 《Bulletin of experimental biology and medicine》1993,116(6):1480-1482
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N
o
12, pp. 584–585, December, 1993 相似文献
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Yoshiaki Norimatsu Ph.D. C.F.I.A.C. Hiroyuki Ohsaki Ph.D. C.F.I.A.C. Kenji Yanoh M.D. Ph.D. Namiki Kawanishi C.T. I.A.C. Tadao K. Kobayashi Ph.D. C.F.I.A.C. 《Diagnostic cytopathology》2013,41(4):303-307
It is well known that “condensed cluster of stromal cells (CCSC)” and “metaplastic clumps with irregular protrusion (MCIP)” in endometrial glandular and stromal breakdown (EGBD) cases may simulate “clumps of cancer cells (CCC)” in endometrioid adenocarcinoma grade 1 (G1), leading to difficulty in cytological interpretation. The aim of this study was undertaken to clarify the cytological immunoreactivity of nuclear findings about CCSC and MCIP which may be recognized in EGBD cases by using p53 protein and cyclin A in liquid‐based cytologic (LBC) preparations. The material consists of cytologic smears of 20 cases of EGBD and 20 cases of G1 for which histopathological diagnosis was obtained by endometrial curettage at the JA Suzuka General Hospital. The evaluation of immunoreactivity was performed by using the intensity of nuclear staining and the nuclear labeling index (N‐LI). The intensity of nuclear staining was scored as negative (0), weak (1), moderate (2), or strong (3). The N‐LI was scored as less than 10% (0), from 10 to 25% (1), from 26 to 50% (2), or greater than 50% (3). The final score was calculated of the addition of both partial scores. Results are as follows: As for the p53 protein immunoreactivity, CCC (2.4 ± 1.4) was a significantly higher value in comparison with CCSC (0) and MCIP (0.8 ± 0.4), respectively. As for the cyclin A immunoreactivity, CCC (2.8 ± 1.1) was a significantly higher value in comparison with CCSC (0) and MCIP (0.6 ± 0.5), respectively. CCSC and MCIP in EGBD are misunderstood as cellular atypia and structural atypia on occasion; but, as for results of the immunoreactivity scores of p53 protein and cyclin A in our study, it seemed that those biochemical characters proved that the biological activity level was low (or degenerative). The results of the current study demonstrated that the cytological immunoreactivity of nuclear findings by p53 and cyclin A appear to be more useful for the LBC assessment of endometrial lesions, especially for the discrimination of EGBD and G1.Diagn. Cytopathol. 2013;41:303–307. © 2011 Wiley Periodicals, Inc. 相似文献
7.
目的 建立心脏过表达人源PRKAG2 (G100S)的转基因小鼠模型,为进一步研究该人源基因点突变对小鼠心脏发育、形态和功能维持的作用奠定基础.方法 克隆人源基因PRKAG2并构建点突变质粒,将人源PRKAG2 (G100S)插入α肌球蛋白重链(α-MHC)启动子下游,构建转基因表达载体.选用C57BL/6J小鼠为遗传背景,通过显微注射法建立人源PRKAG2(G100S)转基因小鼠模型,利用特异引物PCR法鉴定转基因小鼠的基因型.采用实时荧光定量PCR(qPCR)和蛋白质印迹法检测人源PRKAG2 (G100S)的表达.结果 经过回交繁育后建立了2个品系的心脏特异表达人源PRKAG2(G100S)的转基因小鼠品系F2代,并通过qPCR、蛋白质印迹法检测,确认了转基因小鼠心脏组织中人源PRKAG2(G100S)在rmRNA和蛋白水平存在过表达,且该突变能在转基因小鼠中稳定传代.结论 本研究成功建立了心脏特异表达人源PRKAG2(G100S)转基因小鼠模型,人源PRKAG2 (Gl00S)基因在心脏组织的过度表达在小鼠心脏发育和功能维持中的作用需要进一步深入研究与探讨. 相似文献
8.
Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestational day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. 相似文献
9.
To date, breakdown voltage is an underlying risk to the epoxy-based electrical high voltage (HV) equipment. To improve the breakdown strength of epoxy resin and to explore the formation of charge traps, in this study, two types of polyhedral oligomeric silsesquioxane (POSS) fillers are doped into epoxy resin. The breakdown voltage test is performed to investigate the breakdown strength of neat epoxy and epoxy/POSS composites. Electron traps that play an important role in breakdown strength are characterized by thermally stimulated depolarized current (TSDC) measurement. A quantum chemical calculation tool identifies the source of traps. It is found that adding octa-glycidyl POSS (OG-POSS) to epoxy enhances the breakdown strength than that of neat epoxy and epoxycyclohexyl POSS (ECH-POSS) incorporated epoxy. Moreover, side groups of OG-POSS possess higher electron affinity (EA) and large electronegativity that introduces deep-level traps into epoxy resin and restrain the electron transport. In this work, the origin of traps has been investigated by the simulation method. It is revealed that the functional properties of POSS side group can tailor an extensive network of deep traps in the interfacial region with epoxy and enhance the breakdown strength of the epoxy/POSS nanocomposite. 相似文献
10.
Skourtis SS Balabin IA Kawatsu T Beratan DN 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(10):3552-3557
We compute the autocorrelation function of the donor-acceptor tunneling matrix element for six Ru-azurin derivatives. Comparison of this decay time to the decay time of the time-dependent Franck-Condon factor {computed by Rossky and coworkers [Lockwood, D. M., Cheng, Y.-K. & Rossky, P. J. (2001) Chem. Phys. Lett. 345, 159-165]} reveals the extent to which non-Condon effects influence the electron-transfer rate. is studied as a function of donor-acceptor distance, tunneling pathway structure, tunneling energy, and temperature to explore the structural and dynamical origins of non-Condon effects. For azurin, the correlation function is remarkably insensitive to tunneling pathway structure. The decay time is only slightly shorter than it is for solvent-mediated electron transfer in small organic molecules and originates, largely, from fluctuations of valence angles rather than bond lengths. 相似文献