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排序方式: 共有715条查询结果,搜索用时 15 毫秒
31.
Elisabeth M. Haberl Thomas S. Weiss Georg Peschel Kilian Weigand Nikolai Khler Josch K. Pauling Jürgen J. Wenzel Marcus Hring Sabrina Krautbauer Gerhard Liebisch Christa Buechler 《International journal of molecular sciences》2021,22(10)
Hepatocellular carcinoma (HCC) still remains a difficult to cure malignancy. In recent years, the focus has shifted to lipid metabolism for the treatment of HCC. Very little is known about hepatitis B virus (HBV) and C virus (HCV)-related hepatic lipid disturbances in non-malignant and cancer tissues. The present study showed that triacylglycerol and cholesterol concentrations were similar in tumor adjacent HBV and HCV liver, and were not induced in the HCC tissues. Higher levels of free cholesterol, polyunsaturated phospholipids and diacylglycerol species were noted in non-tumorous HBV compared to HCV liver. Moreover, polyunsaturated phospholipids and diacylglycerols, and ceramides declined in tumors of HBV infected patients. All of these lipids remained unchanged in HCV-related HCC. In HCV tumors, polyunsaturated phosphatidylinositol levels were even induced. There were no associations of these lipid classes in non-tumor tissues with hepatic inflammation and fibrosis scores. Moreover, these lipids did not correlate with tumor grade or T-stage in HCC tissues. Lipid reprogramming of the three analysed HBV/HCV related tumors mostly resembled HBV-HCC. Indeed, lipid composition of non-tumorous HCV tissue, HCV tumors, HBV tumors and HBV/HCV tumors was highly similar. The tumor suppressor protein p53 regulates lipid metabolism. The p53 and p53S392 protein levels were induced in the tumors of HBV, HCV and double infected patients, and this was significant in HBV infection. Negative correlation of tumor p53 protein with free cholesterol indicates a role of p53 in cholesterol metabolism. In summary, the current study suggests that therapeutic strategies to target lipid metabolism in chronic viral hepatitis and associated cancers have to consider disease etiology. 相似文献
32.
S. P. Yakovlev S. A. Loginov A. V. Kosul'nikov A. V. Myl'tsin 《Chemistry and Technology of Fuels and Oils》2003,39(1-2):54-59
The method is based on use of fluidics — an injection system for feed of feedstock and air. Introduction in asphalt production at Ryazan' Oil Refining Co. showed: equipping the oxidizing reactor with an injection system allowed obtaining viscous paving asphalts for which all parameters exceeded the requirements of GOST 22245–90, TU 38.1011356–91, and Neste specifications; stable operation of the reactor was attained in all output ranges; the injection feed system is distinguished by simplicity and reliability, and coking problems are totally eliminated; the investments are insignificant, the output of the oxidizing reactors is increased, and specific air consumption is reduced. 相似文献
33.
In Ukraine, average and maximum concentrations of certain pollutants in inland water bodies are unacceptably high, while the number of heavy pollution accidents (one‐out effluent discharges capable of causing health hazards) is increasing. Meanwhile, the transition from a centrally planned to a free market economy is associated with severe economic downturn and a marked industrial decline. However, no comprehensive analyses related to issues linking water pollution and socio‐economic situation during the period 1991–2003 have been done. It is considered unlikely that much can be achieved to improve water quality, at the state level, in the near future. Some improvement can be achieved through changes in the system of pollution control and in public attitude, as well as obtaining relevant expertise and funds from abroad. 相似文献
34.
V. A. Grigor’ev V. A. Kaplin T. L. Karavicheva O. V. Karavichev N. V. Kondrat’eva A. B. Kurepin A. N. Kurepin V. A. Loginov V. N. Marin A. I. Maevskaya A. I. Reshetin W. H. Trzaska 《Instruments and Experimental Techniques》2009,52(3):352-356
Measurements of the pulse heights in the T0 start trigger detector of the ALICE experiment are necessary both for time-amplitude offline correction of start signal T0 used in the time-of-flight TOF detector and for monitoring the state of the Cherenkov counters in the detector. A high amplitude resolution is not required for these tasks; what is needed is fast encoding and interfacing with the data readout system in which only time channels are available. Therefore, amplitudes are measured in the detector by pulse-height-to-time conversion using two independent methods, one of which involves quasi-logarithmic charge-to-time converter (QTC) and the other employs two—leading-edge (LED) and constant-fraction (CFD)—timing discriminators. The main characteristics of both methods and results of calibrations of the appropriate devices using a pulsed laser are presented. 相似文献
35.
N. P. Loginov 《Combustion, Explosion, and Shock Waves》2009,45(1):64-69
Decomposition of lead azide (LA), pentaerythrite tetranitrate (PETN), and a laminate system composed of these substances under vibrational loading is considered. Sensitivity of these substances to impact and vibrations is determined. Sensitivity of the LA + PETN laminate system to vibrational loading, which is characterized by the degree of decomposition, is substantially higher than that of PETN, but lower than that of LA. Specific features of the mechanism of decomposition of these substances at moderate values of vibration parameters and temperatures of specimen heating are discussed. __________ Translated from Fizika Goreniya i Vzryva, Vol. 45, No. 1, pp. 73–79, January–February, 2009. 相似文献
36.
Oleksii Parniakov Olivier Bals Viacheslav Mykhailyk Nikolai Lebovka Eugene Vorobiev 《Food and Bioprocess Technology》2016,9(2):243-251
The effects of pulsed electric fields (PEF) and osmotic impregnation in glycerol solution on the amount of unfreezable water in apple were determined by means of low-temperature differential scanning calorimetry (DSC). The obtained data were compared with behaviour of pure water–glycerol solutions (sample WG). PEF treatment was applied using a near-rectangular monopolar generator with pulse duration of 100 μs at electric field strength of 800 V/cm. The osmotic impregnation of PEF-treated apple discs was done using water–glycerol (sample AWG) and apple juice–glycerol (sample AJG) osmotic solutions at different concentration of water or juice in glycerol, W = 30–100 wt%. The data evidenced that for the PEF-treated samples the glycerol was able to penetrate successfully inside apple tissue. The state diagrams for WG, AWG and AJG samples were rather similar. It was observed that free water existed only for moisture content above some minimum value. The unfreezable water content was the largest in AJG, followed by WG and AWG. The juice concentration in glycerol W ≈ 80 wt% was found to be optimal for preservation of the texture of PEF-treated samples. 相似文献
37.
Molecular models of all known subtypes (A1, A2A, A2B, and A3) of the human adenosine receptors were built in homology with bovine rhodopsin. These models include the transmembrane domain as well as all extracellular and intracellular hydrophilic loops and terminal domains. The molecular docking of adenosine and 46 selected derivatives was performed for each receptor subtype. A binding mode common for all studied agonists was proposed, and possible explanations for differences in the ligand activities were suggested. 相似文献
38.
39.
S. A. Feshchenko V. I. Pleshkov B. N. Lizunov A. A. Lapshin K. N. Soveiko V. N. Loginov L. E. Vasil’ev 《Metallurgist》2007,51(11-12):605-611
Subjecting natural gas to multi-stage heating by passing it through the cooled cavities of certain tuyere elements instead of coolant water is technically simple to accomplish and makes it possible to heat the gas to 300°C or more, the exact temperature depending on the amount of gas used. The cost of instituting this technology is an order of magnitude lower than the savings realized by injecting heated natural gas into blast furnaces. The injection of heated natural gas into a blast furnace introduces additional heat into the furnace and makes it possible to use more natural gas in the smelting process without reducing the theoretical combustion temperature. It also increases the value of the coefficient that characterizes the replacement of coke by natural gas, since the gas undergoes more complete combustion in this case. Finally, the injection of heated natural gas results in a more uniform distribution of hydrogen across the furnace and allows fuller use of this element in the smelting operation. 相似文献
40.
A thermal analysis of clays of the Gzhel' deposit is performed and their mineral composition is established. The effect of various admixtures and minerals and the dispersity on the behavior of the clays during heating is described. 相似文献