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31.
The drugs based on platinum metals represent one of the oldest, but also one of the most effective groups of chemotherapeutic agents. Thanks to many clinical studies it is known that resistance of tumor cells to drugs is a frequent cause of chemotherapy failure. With regard to platinum based drugs, multidrug resistance can also be connected with increased expression of low-molecular weight protein metallothionein (MT). This study aimed at investigating the interactions of MT with cisplatin or carboplatin, using the adsorptive transfer technique coupled with differential pulse voltammetry Brdicka reaction (AdTS DPV Brdicka reaction), and a comparison of in vitro results with results obtained in vivo. The results obtained from the in vitro study show a strong affinity between platinum based drugs and MT. Further, we analyzed extracts of neuroblastoma cell lines treated with cisplatin or carboplatin. It is clear that neuroblastoma UKF-NB-4 cisplatin-resistant and cisplatin-sensitive cell lines unlikely respond to the presence of the platinum-based cytostatics cisplatin and carboplatin. Finally, we determined the level of MT in samples from rabbits treated with carboplatin and patients with retinoblastoma treated with the same drug.  相似文献   
32.
Silicon - We designed a new model tunnel field-effect transistor (TFET) based on Triple Heterojunction Tunnel Field Effect Transistor (THJ-TFET) is investigated and designed in this paper. This...  相似文献   
33.
ABSTRACT:  The objective was to examine the effects of potassium lactate (KL) and raw-meat blend on the shelf-life of fresh-pork-sausage patties in lighted and unlighted display. Four fresh-pork-sausage blends (70% prerigor meat, 30% fresh-pork trim; 80%/20%; 90%/10%; and 100%/0%) were formulated ( n = 3) with 0% and 3% KL, and patties were displayed for 10 d at 4 °C in lighted display or for 7 d in unlighted display followed by 3 d in lighted display. Patties with KL had lower aerobic plate counts (APC), more stable color (greater a* and chroma, less visual discoloration), and less lipid oxidation ( P < 0.05) during display than did patties without KL. Patties in the light for 10 d were more discolored and had more lipid oxidation ( P < 0.05) than those in the dark for 7 d followed by the light for 3 d. Patties with KL in the light for 10 d had similar color ( P > 0.05) to patties without KL that were in the dark for the first 7 d. Adding KL resulted in similar color stability ( P > 0.05) among patties made from 80, 90, and 100% prerigor meat and greater color stability ( P < 0.05) than similarly formulated patties without KL. By using 3% KL, fresh-pork-sausage patty color stability was maximized, APC and lipid oxidation were minimized, and formulation costs can be decreased by using less-expensive fresh-pork trim for up to 20% of the blend. Adding KL also minimized the effects of display lighting on myoglobin and lipid oxidation.  相似文献   
34.
EuQoS is the acronym for "end-to-end quality of service support over heterogeneous networks", which is a European research project aimed at building an entire QoS framework, addressing all the relevant network layers, protocols, and technologies. This framework, which includes the most common access networks (xDSL, UMTS, WiFi, and LAN) is being prototyped and tested in a multidomain scenario throughout Europe, composing what we call the EuQoS system. In this article we present the novel QoS routing mechanisms that are being developed and evaluated in the framework of this project. The preliminary performance results validate the design choices of the EuQoS system, and confirm the potential impact this project is likely to have in the near future  相似文献   
35.
Zieger P  Ruhtz T  Preusker R  Fischer J 《Applied optics》2007,46(35):8542-8552
We have designed an airborne spectrometer system for the simultaneous measurement of the direct sun irradiance and the aureole radiance in two different solid angles. The high-resolution spectral radiation measurements are used to derive vertical profiles of aerosol optical properties. Combined measurements in two solid angles provide better information about the aerosol type without additional and elaborate measuring geometries. It is even possible to discriminate between absorbing and nonabsorbing aerosol types. Furthermore, they allow to apply additional calibration methods and simplify the detection of contaminated data (e.g., by thin cirrus clouds). For the characterization of the detected aerosol type a new index is introduced that is the slope of the aerosol phase function in the forward scattering region. The instrumentation is a flexible modular setup, which has already been successfully applied in airborne and ground-based field campaigns. We describe the setup as well as the calibration of the instrument. In addition, example vertical profiles of aerosol optical properties--including the aureole measurements--are shown and discussed.  相似文献   
36.
37.
Security and privacy in mobile ad-hoc peer-to-peer environments are hard to attain, especially when working with passive objects (without own processing power, e.g. RFID tags). This paper introduces a method for integrating such objects into a peer-to-peer environment without infrastructure components while providing a high level of privacy and security for peers interacting with objects. The integration is done by associating public keys to passive objects, which can be used by peers to validate proxies (peers additionally acting on behalf of objects). To overcome the problem of limited storage capacity on small embedded objects, ECC keys are used.  相似文献   
38.
In on-line dial-a-ride problems servers are traveling in some metric space to serve requests for rides which are presented over time. Each ride is characterized by two points in the metric space, a source, the starting point of the ride, and a destination, the endpoint of the ride. Usually it is assumed that at the release of a request, complete information about the ride is known. We diverge from this by assuming that at the release of a ride, only information about the source is given. At visiting the source, the information about the destination will be made available to the servers. For many practical problems, our model is closer to reality. However, we feel that the lack of information is often a choice, rather than inherent to the problem: additional information can be obtained, but this requires investments in information systems. In this paper we give mathematical evidence that for the problem under study it pays to invest.  相似文献   
39.
Polymers are currently widely used to replace a variety of natural materials with respect to their favourable physical and chemical properties, and due to their economic advantage. One of the most important branches of application of polymers is the production of different products for medical use. In this case, it is necessary to face a significant disadvantage of polymer products due to possible and very common colonization of the surface by various microorganisms that can pose a potential danger to the patient. One of the possible solutions is to prepare polymer with antibacterial/antimicrobial properties that is resistant to bacterial colonization. The aim of this study was to contribute to the development of antimicrobial polymeric material ideal for covering vascular implants with subsequent use in transplant surgery. Therefore, the complexes of polymeric substances (hyaluronic acid and chitosan) with silver nitrate or silver phosphate nanoparticles were created, and their effects on gram-positive bacterial culture of Staphylococcus aureus were monitored. Stages of formation of complexes of silver nitrate and silver phosphate nanoparticles with polymeric compounds were characterized using electrochemical and spectrophotometric methods. Furthermore, the antimicrobial activity of complexes was determined using the methods of determination of growth curves and zones of inhibition. The results of this study revealed that the complex of chitosan, with silver phosphate nanoparticles, was the most suitable in order to have an antibacterial effect on bacterial culture of Staphylococcus aureus. Formation of this complex was under way at low concentrations of chitosan. The results of electrochemical determination corresponded with the results of spectrophotometric methods and verified good interaction and formation of the complex. The complex has an outstanding antibacterial effect and this effect was of several orders higher compared to other investigated complexes.  相似文献   
40.
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