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991.
992.
S Nakajima H Hayashi Y Omote Y Yamazaki S Hirata T Maeda Y Kubo T Takemura Y Kakiuchi Y Shindo 《Journal of photochemistry and photobiology. B, Biology》1990,7(2-4):189-198
The tumour-localizing abilities of various kinds of porphyrin derivatives in tumour-bearing hamsters were assessed by nitrogen-pulsed laser spectrofluorometry (N2-PLS). On examination of porphine derivatives (from haemoglobin), it was found that the dimer and acetylated and amidated compounds had a high affinity for tumour tissue; the dimer and hydroxylated compound of phorbine derivatives (from chlorophyll) also showed a high affinity. Furthermore, of the metalloporphines (gallium, zinc and indium complexes), those which contained hydrophilic groups showed a high affinity for tumour tissue; of the metallophorbines (gallium, zinc and indium complexes), those which contained hydrophobic groups showed a high affinity. A correlation was found between the side-chain structure of the porphyrins and metalloporphyrins and their affinity for tumour tissue. 相似文献
993.
994.
995.
K. Kaya T. Sugioka T. Taguwa K. Hoshino A. Nakajima 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,26(Z1):201-203
Sodium doped silicon clusters (SinNam, 3n11, 1m4) were produced by two independent laser vaporization methods and their ionization potentials were measured by scanning the wavelength of the UV dye laser. The IPs of most SinNam clusters decrease monotonously with the number of Na atoms, but IPs of Si7Nam and Si10Nam clusters show an apparent even-odd alternation; odd numbers of Na atoms efficiently decrease the IP but even numbers of Na atoms never significantly decrease the IPs. In addition, the reactivity of SinNam clusters for NO molecules was investigated with a fast flow reactor, and an anti-correlation between IP and the reactivity was clearly observed; clusters having high IP show low reactivity andvice versa. 相似文献
996.
997.
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999.
T. Kambara J. Suzuki H. Yoshioka N. Nakajima 《Journal of Radioanalytical and Nuclear Chemistry》1978,43(1):139-146
Isotope dilution analysis using the redox substoichiometric principle has been applied to the determination of antimony content
in metallic zinc. As the substoichiometric reaction, the oxidation of trivalent to pentavalent antimony with potassium permanganate
was used, followed by separation of these species by the BPHA extraction of trivalent antimony. Determination of antimony
contents less than 0.5 μg was found to be possible with good accuracy, without separation of zinc ions. The antimony content
in metallic zinc was determined to be 19.7±0.8 ppm, in good agreement with the results obtained by the other analytical methods. 相似文献
1000.
Suzuki Y Sazaki G Matsui T Nakajima K Tamura K 《The journal of physical chemistry. B》2005,109(8):3222-3226
The growth and dissolution rates of glucose isomerase crystals ({1 0 1} face) were measured in situ at 0.1 and 100 MPa. From these data, we determined that the solubilities at 25 degrees C were C(e) = 3.1 +/- 0.9 and 2.6 +/- 0.5 mg mL(-1) at 0.1 and 100 MPa, respectively. At the same supersaturation of sigma = 2.5 (sigma identical with ln(C/C(e)), C = the concentration of glucose isomerase, C(e) = the solubility) and temperature (T = 25 degrees C), the growth rate under 100 MPa was 7.6 times larger than that under 0.1 MPa. This result shows, for the first time, a kinetic acceleration of the growth rates of protein crystals with increasing pressure. The growth rates vs sigma data fitted well with a two-dimensional nucleation growth model of a polynucleation type. The fitting results indicate that the acceleration is mainly due to the decrease in the molecular surface energy of the glucose isomerase crystal with pressure. 相似文献