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291.
Králová J Koivukorpi J Kejík Z Poucková P Sievänen E Kolehmainen E Král V 《Organic & biomolecular chemistry》2008,6(9):1548-1552
This paper describes the preparation and use of conjugates of porphyrins and bile acids as ligands to bind to tumor expressed saccharides. Bile acid-porphyrin conjugates were tested for recognition of saccharides that are typically present on malignant tumor cells. Fluorescence microscopy, in vitro PDT cell killing, and PDT of subcutaneous 4T1 mouse tumors is reported. High selectivity for saccharide cancer markers and cancer cells was observed. This in vivo and in vitro study demonstrated high potential use for these compounds in targeted photodynamic therapy. 相似文献
292.
The purpose of this investigation was to study voice changes during a working day. The subjects consisted of 33 female primary and secondary schoolteachers who recorded their first and last lessons during one school day. The subjects were studied both as one group and two subgroups (those with many and those with few voice complaints). Estimates of fundamental frequency (F0), sound pressure level (SPL), the standard deviations of these values (F0 SD; SPL SD) and F0 time (vibration time of vocal folds) were made. The most obvious change due to loading was the rise of F0 that was 9.7 Hz between the first and last lesson (P = 0.00). F0 increased more (12.8. Hz, P = 0.006) in the subgroup with few complaints. 相似文献
293.
** Email: Erkki.Jantunen{at}vtt.fi Tool wear monitoring is important for a number of reasons. Automaticdiagnosis of tool wear enables the unmanned use of flexiblemanufacturing systems and machine tools. Besides, a worn toolif unnoticed could cause a lot of damage, i.e. the machinedproducts could be damaged and unfit for their planned use. Assuch the machining process is very challenging to monitor dueto various reasons. Tool type and cutting parameters may varyresulting in variation of the monitored parameters. Also, therecan be a lot of noise in the measured signals. The paper dealswith the use of regression analysis techniques together withfuzzy logic in order to overcome the challenges in tool wearmonitoring. Regression analysis, based on a higher order polynomialfunction that emphasizes the most recent measured data and hasa limited number of terms, can very well follow and give prognosisof the development of the monitored parameters from such signalsas vibration, sound and acoustic emission. The use of fuzzylogic makes it possible to automatically define limits for themonitored parameters and to combine the information from a numberof signals. The proposed approach is tested with data from drillingtests. 相似文献
294.
Link M Hakala KS Wsól V Kostiainen R Ketola RA 《Journal of mass spectrometry : JMS》2006,41(9):1171-1178
We present a detailed experimental approach to detection and subsequent structural characterization of unknown metabolites of sibutramine, using liquid chromatography-mass spectrometric techniques. The full-, precursor ion, and constant neutral loss scan modes of a triple quadrupole mass spectrometer were used for screening sibutramine metabolites in human urine. The structural assessment of unknown metabolites was based on MSn ion trap mass spectrometric analysis and comparison of MSn spectra between the standards and compounds detected. Two phase-I (M1 and M2) and eight phase-II (M3-M6) metabolites of sibutramine were found in human urine. Metabolites M1 and M2, which were found as minor metabolites, originated from N-demethylation of sibutramine. Carbamoyl glucuronides formed from metabolites M1, M2, and their hydroxylated analogs were the main metabolites of sibutramine and were characterized by tandem mass spectrometric analysis and by the chemical modification of their structure. We demonstrate the usefulness of the chemical derivatization approach for estimation of the site of glucuronidation and propose the formation of hydroxylated regioisomers of metabolites M4 and M6. 相似文献
295.
296.
Vadim P. Sirkeli Dmitrii D. Nedeoglo Natalia D. Nedeoglo Ivan V. Radevici Raisa L. Sobolevskaia Konstantin D. Sushkevich Erkki Lähderanta Alexander V. Lashkul Reino Laiho Jens-Peter Biethan Oktay Yilmazoglu Dimitris Pavlidis Hans L. Hartnagel 《Physica B: Condensed Matter》2012,407(18):3802-3807
Magnetic and photoluminescent properties of manganese-doped ZnSe crystals with different impurity concentrations were investigated. The concentration of Mn2+ ions in ZnSe crystals has been varied from 0.01 to 0.3 at%. Magnetic and photoluminescent studies have confirmed the introduction of Mn in ZnSe crystals. It was established that Mn2+ ions are responsible for the emission bands with maximum at 616 nm and 633 nm, which correspond to 4T2→6A1 and 4T1→6A1 intracentre transitions of Mn2+ ions respectively. It was found that the concentration quenching of the photoluminescent bands is associated with Mn2+ ions, which are due to the formation of Mn–Mn clusters. Magnetic properties studies have shown that at high doping levels the manganese atoms form Mn–Mn clusters in ZnSe. From the temperature dependence of magnetic susceptibility of ZnSe:Mn crystals that follows the Curie–Weiss law, it was possible to estimate the Curie–Weiss temperature Θ(x) and the effective Mn–Mn antiferromagnetic exchange constant (J1). 相似文献
297.
J Hakala J Dobaczewski D Gorelov T Eronen A Jokinen A Kankainen VS Kolhinen M Kortelainen ID Moore H Penttilä S Rinta-Antila J Rissanen A Saastamoinen V Sonnenschein J Aystö 《Physical review letters》2012,109(3):032501
Atomic masses of the neutron-rich isotopes ^{121-128}Cd, ^{129,131}In, ^{130-135}Sn, ^{131-136}Sb, and ^{132-140}Te have been measured with high precision (10?ppb) using the Penning-trap mass spectrometer JYFLTRAP. Among these, the masses of four r-process nuclei ^{135}Sn, ^{136}Sb, and ^{139,140}Te were measured for the first time. An empirical neutron pairing gap expressed as the odd-even staggering of isotopic masses shows a strong quenching across N=82 for Sn, with a Z dependence that is unexplainable by the current theoretical models. 相似文献
298.
Timo V. Laine Kristian Lappalainen Jonas Liimatta Erkki Aitola Barbro Lfgren Markku Leskel 《Macromolecular rapid communications》1999,20(9):487-491
Three pyridylimine based complexes of NiII and CoII were reacted with methylaluminoxane (MAO) and tested as catalysts in ethylene polymerization. The two nickel catalysts produced mainly methyl branched polymers with good to moderate activity, while the cobalt compound showed only marginal activity. Reaction conditions strongly affect the polymer properties, such as molecular weight, melting temperature, degree of branching, and chain end unsaturation type. 相似文献