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41.
Adriamycin linked to oxidized dextran (ADM-OXD) via Schiff's base formation was compared with free adriamycin with regard to antitumor activity, acute toxicity and plasma pharmacokinetics in rats following i.v. administration. ADM-OXD showed higher activity against Walker carcinosarcoma 256 than free adriamycin. On the other hand, the acute toxicity of ADM-OXD was about three times less than that of free adriamycin. In contrast to free adriamycin, a very high plasma level of adriamycin was found after i.v. administration of ADM-OXD. The area under the plasma concentration curve with ADM-OXD was about 160-fold higher than with free adriamycin. Thus, the improvement of the therapeutic index in the case of ADM-OXD might be due to the difference in the disposition of ADM-OXD and free adriamycin in rats.  相似文献   
42.
Two-photon ionisation processes of rare-gas atoms produced by a superposition of multiple high order harmonics are studied by using a photoelectron spectroscopy technique. Second-order nonlinearity is confirmed by comparing the intensity-dependent photoelectron yields between the linear and nonlinear processes, and the cross sections of these processes are estimated. We also demonstrate the autocorrelation measurement of harmonic envelopes as a preliminary step toward characterisation of an attosecond pulse train. PACS 32.80.Fb; 32.80.Wr; 42.65.-k  相似文献   
43.
The combination of plasma discharge and adsorption was examined for oxidation of dilute benzene in air in a plasma reactor packed with a mixture of BaTiO 3 pellets and porous Al 2 O 3 pellets (i.e., an alumina hybrid reactor). The oxidative decomposition of benzene was enhanced by the benzene concentrating on the Al 2 O 3 pellets. Furthermore, there was a higher selectivity to CO 2 in the products from the hybrid than from a plasma reactor packed with BaTiO 3 pellets alone. The presence of the Al 2 O 3 pellets suppressed the formation of N 2 O.  相似文献   
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Directed lithiation of p-tolyl 1-azulenyl sulfone (1) at the 2-position of the azulenyl group was achieved by using lithium 2,2,6,6-tetramethylpiperidide (LTMP). The azulenyllithium thus generated could be efficiently trapped with various electrophiles to form 2-substituted derivatives 2 in moderate to good yields. p-Tolyl 2-trimethylsilyl-1-azulenyl sulfone (2a) was transformed into cyclic sulfone derivative 3a through the directed lithiation in the p-tolyl group and subsequent intramolecular ring closure at the 8-position. 2-(Phenylsulfanyl)-1-azulenyl p-tolyl sulfone (2b) suffered from desulfonylation to form 2-phenylsulfanylazulene (4). The Suzuki coupling reaction of 2-iodo-1-azulenyl p-tolyl sulfone (2d) with arylboronic acids followed by desulfonylation efficiently gave 2-arylazulenes 10.  相似文献   
46.
Pure elastic and inelastic scattering cross sections have been measured for the systems 58Ni +90,94Zr at energies near the Coulomb barrier where not only quasi-elastic and fusion but also deep-inelastic process come into play. Coupled channels calculations including both projectile and target inelastic excitations can successfully explain the elastic and inelastic scattering angular distributions with an energy-independent semi-empirical bare potential. The calculation reproduces also the sum of the total quasi-elastic, fusion and deep-inelastic cross sections. Received: 14 September 1998 / Revised version: 21 October 1998  相似文献   
47.
A protocol for the synthesis of pyrrolo-p-phenylene-linked porphyrin-fullerene dyads suitable as photoactive materials was developed. The sequence of aziridination – aziridine ring opening – 1,3-dipolar cycloaddition reactions enabled us to provide structural variability both to the porphyrin core and to pyrrole linker, which facilitates designing the electronic structure and morphological parameters of the dyads. The key porphyrin building blocks, nitro-porphyrins, were synthesized by a stochastic cyclocondensation of arenecarbaldehydes with p-nitrophenyl(dipyrrolyl)methane.  相似文献   
48.

Pressure response of human cells was investigated. Various proteins in the human promyelocytic cells (HL-60), compressed for 30 minutes at a pressure of 100 MPa and at a temperature of 37 °C, were detected by 2-dimensional gel electrophoresis (2-DE). The amount of f - and g -tubulin decreased appreciably immediately after decompression. It suggests that the decrease of tubulin promotes the pressure-induced apoptosis. The amount of heat shock proteins, HSP60 and HSP70 increased immediately after decompression on 2-DE. These proteins may increase to correct the pressure-induced disorder in folding of protein molecules.  相似文献   
49.
Laser-induced fluorescence spectra of Ne- and Ar -aniline complexes were observed with a resolution of 0.04 cm?1. By a simulation analysis of the rotational structures, the distances between the rare-gas atom and the aromatic ring of aniline were found to be 3.35 ± 0.04 and 3.50 ± 0.04 A in the X?1A1 state of the Ne and Ar complexes, respectively, and about 0.05 A shorter when aniline was excited to the Ã1B2 state.  相似文献   
50.
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