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51.
N-myc2 and insulin-like growth factor II (IGF-II) are coordinately overexpressed in the great majority of altered hepatic foci, which are the earliest precancerous lesions observed in the liver of woodchuck hepatitis virus carrier woodchucks, and these genes continue to be overexpressed in hepatocellular carcinomas (HCCs). We have investigated the function of these genes in woodchuck hepatocarcinogenesis by using a woodchuck liver epithelial cell line (WC-3). WC-3 cells react positively with a monoclonal antibody (12.8.5) against woodchuck oval cells, suggesting a lineage relationship with oval cells. Overexpression of N-myc2 in three WC-3 cell lines caused their morphological transformation and increased their growth rate and saturation density in medium containing 10% serum. Removal of serum from the medium increased cell death of the N-myc2-expressing lines, whereas cell death in control lines was minimal. The death of N-myc2-expressing WC-3 cells was accompanied by nucleosomal fragmentation of cellular DNA, and DAPI (4',6-diamidino-2-phenylindole) staining revealed condensation and fragmentation of the nuclei, suggesting that N-myc2-expressing WC-3 cells undergo apoptosis in the absence of serum. In colony regression assays, conducted in the absence of serum, control colonies were stable, while N-myc2-expressing colonies regressed to various degrees. Addition of recombinant human IGF-II to the serum-free medium blocked both cell death and colony regression in all the N-myc2-expressing lines. Therefore, coordinate overexpression of N-myc2 and IGF-II in woodchuck altered hepatic foci may allow cells which otherwise might die to survive and progress to hepatocellular carcinoma.  相似文献   
52.
Under normal physiologic conditions the level of circulating red blood cells is regulated precisely by the glycoprotein erythropoietin. In major elective surgery, patients who are participating in preoperative autologous blood donation or who are anemic may not have the capacity to manufacture sufficient red blood cells in response to increases in endogenous erythropoietin that is sufficient to avoid perioperative allogeneic blood transfusion. In these patients pharmacologic doses of recombinant human erythropoietin (Epoetin alfa) have been shown to accelerate erythropoiesis, thereby increasing preoperative red blood cell production, hematocrit level, and hemoglobin concentration and reducing exposure to allogeneic blood transfusion. In four large multicenter studies, 869 patients undergoing major elective surgery were treated with a daily regimen (300 or 100 IU/kg x 14 or 15 doses) or a weekly regimen (600 IU/kg x 4 doses) of subcutaneous Epoetin alfa beginning either 2 or 3 weeks before surgery, respectively. Although all Epoetin alfa regimens were effective at accelerating erythropoiesis and increasing red blood cell production, the weekly regimen was the most patient friendly, cost effective regimen for treating preoperative anemia and minimizing patient risk of allogeneic blood transfusion.  相似文献   
53.
In this article, a low-power and energy-efficient hybrid full adder circuit is proposed, which is implemented based on multi-threshold NAND and NOR gates and transmission gate multiplexers. In order to implement this circuit, carbon nano tube field effect transistors are utilised. For evaluating the proposed design, comprehensive simulations are performed with regard to the most important aspects power, delay and power-delay product. The results are presented and displayed the superiority of the proposed cell in different voltage levels, load conditions, temperatures and robustness against process variations.  相似文献   
54.
Faris GW  Copeland RA 《Applied optics》1997,36(12):2686-2688
We report measurements of the wavelength dependence of the 3400-cm(-1) Raman scattering cross section of liquid water for excitation wavelengths between 215 and 550 nm. Using previous measurements of the absolute Raman scattering cross section, we have determined an expression for the wavelength dependence of the absolute Raman cross section for water.  相似文献   
55.
Quantum-dot cellular automata (QCA) is the appearance of new technology and can be a suitable alternative to semiconductor transistor technology. In this paper, the new structure of the two-input XOR gate is presented, which is the modified version of the three-input XOR gate. This structure can be used to design various useful QCA circuits. By utilizing this gate, we design and implement a new full adder structure with 90-degree cells. This structure is designed in a single layer without cross-wiring. The operation of the proposed structure has been verified by QCADesigner version 2.0.3 and energy dissipation investigated by QCAPro tool. We also compared the effectiveness of our structure with the two previous structures.  相似文献   
56.
Electrolyte‐soaked Nafion is commonly used as an ionic polymer in soft actuators. Here, a multitechnique investigation was applied to correlate the electrochemical behavior of Nafion membranes with their microstructures and nanostructures as a function of electrolyte type. The influence of electrolytes of Li salts with different counteranions on the Nafion membranes was investigated in terms of hydration level, structure (using X‐ray diffraction and small angle X‐ray scattering), stress–strain characteristics, and electrochemical behavior (by cyclic voltammetery and electrochemical impedance spectroscopy). The effects of using ionic liquid (IL), as the electrolyte, addition of different supporting solvent and the addition of Li+ ions to water‐free IL‐soaked membranes on the structural and electrochemical properties of Nafion were examined. The nano‐ and microstructure of the Nafion changed considerably as a function of the identity of the electrolyte solution. The electrochemical behavior of the IL‐soaked samples was compared with that of the water‐soaked Li+‐exchanged Nafion. It was seen that the ionic conductivity of the Nafion membranes was reduced significantly when water was replaced by pure IL. Using the supporting solvents increased the conductivity of IL‐soaked Nafion membranes dramatically. The presence of a small amount of Li+ ions together with the IL ions caused a significant decrease in charge transfer resistance and increases in double layer capacitance and in ionic conductivity over that of the water‐free sample and also over water‐soaked Li+‐exchanged Nafion. These findings can be useful to improve the knowledge on Nafion's microstructure and also to improve the electromechanical behavior of Nafion‐based ionic polymer–metal composites actuators. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45239.  相似文献   
57.
58.
Abstract: Little is known about TANF recipients and leavers use of consumer credit. Using data from a 2001 North Carolina household survey of low‐income households, we analyze banking and credit behavior of current and recent welfare recipients in Charlotte, North Carolina. Other things equal, TANF families are 70% less likely than other low‐income families to have a bank account and much more likely to have participated in a credit counseling program. Except for more frequent contact with bill collectors and credit counselors, leavers are no different from other low income families struggling to make ends meet. Race also matters when it comes to accessing mainstream banking and credit systems. Targeted programs help TANF families gain greater access to the financial mainstream. When it comes to specialization programs, however, those involved in the welfare system are not very different from other poor families. However, by virtue of their formal involvement with TANF, this population can be more efficiently served than other low‐income populations. For this reason and the desire to keep families from recycling back onto welfare rolls, TANF programs should address banking and credit issues.  相似文献   
59.
A glass-forming domain is found and studied within Bi2O3–Sb2O3–TeO2 system. The glasses composition were obtained in pseudo-binary xSbO1.5, (1−x)TeO2 for 0.05 ≤ x ≤ 0.20. The constitution of glasses in the system Sb2O3–TeO2 was investigated by DSC, Raman, and Infrared spectroscopy. The influence of a gradual addition of the modifier oxides on the coordination geometry of tellurium atoms has been elucidated based Infrared and Raman studies and showed the transition of TeO4, TeO3+1, and TeO3 units with increasing Sb2O3 content. XRD results reveal the presence of three crystalline: γ-TeO2, α-TeO2, and SbTe3O8 phases during the crystallization process. The density of glasses has been measured. The investigation in the ternary system by the solid state reaction using XRD reveals the existence of a solid solution Bi1−x Sb1−x Te2x O4 isotopic to BiSbO4 with 0 ≤ x ≤ 0.1.  相似文献   
60.
Retinoids are natural and synthetic vitamin A derivatives that are effective for the prevention and the treatment of non-melanoma skin cancers (NMSC). NMSCs constitute a heterogenous group of non-melanocyte-derived skin cancers that impose substantial burdens on patients and healthcare systems. They include entities such as basal cell carcinoma and cutaneous squamous cell carcinoma (collectively called keratinocyte carcinomas), cutaneous lymphomas and Kaposi’s sarcoma among others. The retinoid signaling pathway plays influential roles in skin physiology and pathology. These compounds regulate diverse biological processes within the skin, including proliferation, differentiation, angiogenesis and immune regulation. Collectively, retinoids can suppress skin carcinogenesis. Both topical and systemic retinoids have been investigated in clinical trials as NMSC prophylactics and treatments. Desirable efficacy and tolerability in clinical trials have prompted health regulatory bodies to approve the use of retinoids for NMSC management. Acceptable off-label uses of these compounds as drugs for skin cancers are also described. This review is a comprehensive outline on the biochemistry of retinoids, their activities in the skin, their effects on cancer cells and their adoption in clinical practice.  相似文献   
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