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1.
韦常丽  吴延佳 《实用医技杂志》2007,14(23):3196-3197
<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   
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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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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   
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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   
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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   
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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   
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In this study, Escherichia coli lipopolysaccharide (LPS) dose-dependently (100–300 μg/ml) and time-dependently (10–60 min) inhibited platelet aggregation in human platelets stimulated by agonists. LPS also dose-dependently inhibited the phosphoinositide breakdown and the intracellular Ca+2 mobilization in human platelets stimulated by collagen. LPS (300 μg/ml) also significantly inhibited the thromboxane A2formation stimulated by collagen in human platelets. Moreover, LPS (100–300 μg/ml) dose-dependently decreased the fluorescence of platelet membranes tagged with diphenylhexatrience. In addition, LPS (200 and 300 μg/ml) significantly increased the formation of cyclic GMP but not cyclic AMP in platelets. LPS (200 μg/ml) also significantly increased the production of nitrate within a 30 min incubation period. Rapid phosphorylation of a platelet protein of M r 47 000, a marker of protein kinase C activation, was triggered by phorbol-12-13-dibutyrate (PDBu, 50 n M ). This phosphorylation was markedly inhibited by LPS (200 μg/ml) within a 30 min incubation period.
These results indicate that the antiplatelet activity of LPS may be involved in two important pathways. (1) LPS may induce conformational changes in the platelet membrane, leading to change in the activity of phospholipase C. (2) LPS also activated the formation of nitric oxide (NO)/cyclic GMP in human platelets, resulting in inhibition of platelet aggregation. Therefore, LPS-mediated alteration of platelet function may contribute to bleeding diathesis in septicaemic and endotoxaemic patients.  相似文献   
10.

Objectives

Constituents of dental composites can be released from dental fillings after polymerization. The aim of this study was to examine the time-related elution and breakdown of separable constituents of polymerized composites using deuterated solvents.

Method

Elution and breakdown of constituents were investigated with deuterated solvents methanol and water by gas chromatography/mass spectrometry of following composites for 180 days: Filtek™ Supreme XT, Filtek™ Supreme XT Flow, Tetric Ceram®, Tetric Flow®, Grandio®, Grandio® Flow.

Results

Within 180 days no compounds were formed as the products of breakdown. 19 compounds were identified as elution products: Bis-EMA, TEGDMA, DDDMA, EGDMA, MAA, BPA, CQ, HQME, DMABEE, CSA, BL, TEG, BHT, TINP, TPP, TPSB, DEDHTP, DCHP, ß-PHEA.The highest concentration of Bis-EMA was measured for Tetric Flow® in deuterated methanol on day 90 at 36.993 mmol/l and in deuterated water also on day 90 at 0.031 mmol/l.The highest TEGDMA concentrations were measured for Grandio® Flow in deuterated methanol on day 60 at 1.322 mmol/l and for Filtek™ Supreme XT Flow in deuterated water on day 3 at 0.689 mmol/l. The highest BPA concentration was measured for Tetric Flow® in deuterated methanol on day 90 at 1.469 mmol/l. The highest BPA concentration was measured for Grandio® in deuterated water on day 180 at 0.007 mmol/l.Significance Examination of time-related elution indicates that various elution products (e.g. Bis-EMA, BPA) were only released in small quantities during the first 90 days, but in high quantities between day 90 and day 180.  相似文献   
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