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151.
The interpretation of scintigraphic patterns and the role of pathophysiological mechanisms in patients with primary lung cancer were investigated. To determine the relative roles of perfusion, inhalation and ventilation scintigraphy, the relationship between the count ratio of the affected side to the healthy side and the post-surgical histological lymph nodes factors were observed in this study. These scintigraphic count ratio's in patients with primary lung cancer did not reflect the pN factors except in the perfusion study in patients with hilar primary lung cancer.  相似文献   
152.
The H2O2-photosensitized emulsion copolymerization of tetrafluoroethylene with propylene was carried out at room temperature in the presence of gaseous monomers of 50 mole-% tetrafluoroethylene content. The conversion increased almost linearly with irradiation time. The rate of polymerization was proportional to the 1.0 power of H2O2 concentration up to 3.5 × 10?3M H2O2 and the 0.46 power of H2O2 concentration above 3.5 × 10?3M H2O2. The result obtained at low H2O2 concentration was almost consistent with that obtained in the radiation-induced method. The rate of polymerization was proportional to the 0.58 power of the emulsifier concentration, and the degree of polymerization was independent of the emulsifier concentration. The H2O2-photosensitized emulsion copolymerization of tetrafluoroethylene with propylene is terminated mainly by degradative chain transfer of the propagating radical to propylene at low H2O2 concentration and by the reaction of the propagating radical with OH radical from photolysis of H2O2–aqueous solution at high H2O2 concentration.  相似文献   
153.
An efficient, two-stage, continuous-flow synthesis of 1α,25-(OH)(2)-vitamin D(3) (activated vitamin D(3)) and its analogues was achieved. The developed method afforded the desired products in satisfactory yields using a high-intensity and economical light source, i.e., a high-pressure mercury lamp. In addition, our method required neither intermediate purification nor high-dilution conditions.  相似文献   
154.
An acrylic polymer/silica hybrid resist film was investigated for fabricating a microstructure by electron‐beam (EB) lithography. EB lithography on the hybrid thin film afforded a positive pattern whose depth corresponded to the EB exposure dose; this indicated that the hybrid was an analog resist and could fabricate a three‐dimensional microstructure. The resist film had high heat resistance and compatibility with the underlying quartz plate, probably because of the silica component. The acrylic polymer/(RSiO1.5)n hybrid film showed higher EB sensitivity than a film of the crosslinked acrylic polymer and an acrylic polymer/(SiO2)n hybrid. Atomic force microscopy observation of the hybrid film surface showed the homogeneous dispersion of the acrylic polymer and the silica components in the hybrid film. The acrylic polymer component was EB‐sensitive, whereas dispersing the acrylic polymer and silica components homogeneously also played an important role in increasing the EB sensitivity. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2107–2116, 2006  相似文献   
155.
Mixtures of polystyrene derivatives (PSCS) and poly(vinyl methyl ether) (PVME) were made photocrosslinkable by chemically labeling PSCS chains with photoreactive anthracene. Miscibility of these anthracene-labeled PSCS/PVME blends was examined by light scattering under several crosslinking conditions in the one-phase region via photodimerization of anthracenes. As the reaction proceeds, the coexistence curve of PSCS/PVME blends shifts toward the low temperature side. By following the changes in concentration of anthracenes with irradiation time, it was found that the crosslinking reaction of PSCS chains in the blends does not follow the mean-field kinetics. However, it can be well expressed by the Kohlrausch–Williams–Watts (KWW) relaxation mechanism, indicating that the crosslinking reaction proceeds inhomogeneously in the blends. By scaling the reaction time with the average reaction rate obtained from the KWW equation modified for the reaction kinetics, all the crosslinking data obtained in the miscible region of the reacted blends fall on a single master curve. These experimental results suggest the universal behavior of the photocrosslinking kinetics obtained under the “shallow quench” conditions in the region far away from the coexistence curve of the reacting blends. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 455–462, 1998  相似文献   
156.
157.
The 9,10-dicyanoanthracene-sensitized photooxygenation of biphenyl and its derivatives in the presence of Mg(ClO4)2 in acetonitrile brought about the oxidative cleavage of benzene nucleus to give benzoic acid and its derivatives.  相似文献   
158.
TECHNICAL NOTE     
Abstract— –The use of a proximity type 12 µm microchannel plate photomultiplier (Hamamatsu R1564U) is demonstrated for the accurate determination of picosecond lifetimes of xanthione, stiff stilbene, cryptocyanine, pinacyanol chloride, erythrosin and l, l'-diethyl-2,2'-dicarbocyanine iodide in solution at room temperature. Single curve and global analyses with reference convolution give statistically acceptable mono-exponential fits to all obtained decays. The count rate and wavelength dependence of the measured excitation pulse profile are discussed. Matching the count rates of sample and reference is recommended for reliable picosecond lifetime determinations.  相似文献   
159.
The 9,10-dicyanoanthracene (DCA)-sensitized photooxygenation of biphenyl derivatives in the presence of Mg(CIO4)2 in acetonitrile produces benzoic acid and its derivatives in high yields. In the absence of Mg(CIO4)2, the rates for the consumption of biphenyl derivatives decrease by a factor of 0.5-0.8, compared with those in the presence of Mg(CIO4)2. In these cases, however, both biphenyls and DCA are oxygenated to give benzoic acids and anthraquinone, respectively, indicating that the addition of Mg(CIO4)2 retards the photooxygenation of DCA. With 4-methylbiphenyl, the photooxygenation proceeds efficiently without added Mg(CIO4)2, and benzene rings and methyl groups are competitively oxygenated to give benzoic acid, 4-methylbenzoic acid, 4-phenylbenzoic acid, and 4-phenylbenzaldehyde. The addition of Mg(CIO4)2 facilitates the oxidation of benzene rings, giving benzoic acid and 4-methylbenzoic acid as major products. These photooxygenations are initiated by a one-electron transfer from biphenyls to the excited singlet DCA and proceed via the radical cations of biphenyls and the radical anion of DCA.  相似文献   
160.
Fundamental and clinical characteristics of 3 kinds of high-sensitivity immunoradiometric assay (IRMA) kits for thyroid stimulating hormone (TSH). i.e., RIA BEADS II (kit A), TSH kit Daiichi II (kit B) and Ab tube TSH 'Eiken' (kit C) and one conventional radioimmunoassay (RIA) kit, i.e., TSH kit Daiichi (kit D), were studied. In the recovery test and the reproducibility test, there was no significant difference between the 4 kits. The sensitivities of kits A, B and C were much higher than that of kit D, and those IRMA kits were sensitive enough to distinguish hyperthyroidism from normal samples. For low concentrations of TSH (less than 5 microU/ml), the data from kits D, B, C and A tended to show higher values in that order. The correlation between the data measured by kits B and D, and the tendency of kit A toward lower values agreed well with other reports.  相似文献   
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