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891.
Evaluation of endometrial cancer with 3D-VIBE (volume interpolated breath-hold examination) using intrauterine CO2 gas 总被引:4,自引:0,他引:4
To evaluate the myometrial infiltration of the endometrial cancer prior to aggressive treatment, dynamic MRI (magnetic resonance imaging) has attracted attention. However, it has also been found that in a number of cases, MRI exhibits inconsistent results with regards to the extent of the infiltration into this component of the uterine body. To overcome this limitation, the authors designed a method to delineate the tumor morphology more clearly by injecting CO2 gas into the uterine cavity. This procedure was combined with VIBE (volumetric interpolated breath-hold examination) to determine more precisely the depth of the tumor invasion. From our clinical results, the efficacy of the method was evaluated. On four patients with endometrial cancers (stage Ia-Ic), CO2 was injected to dilate the intra-uterine space through a catheter equipped with a balloon that had been introduced into the uterine cavity, after which VIBE was conducted. The images were interpreted by MPR (multiplanar reconstruction) and the findings from these images were compared against the histopathological findings. By employing this method, it was possible to delineate clearly the tumorous lesion in the uterine body, and three-dimensional images of the tumor invasion was acquired. The site and extent of tumor invasion in the myometrium were generally consistent with the histopathological findings. This method allows one to observe multiple planes by using thin slices. By dilating the uterine cavity, the site of involvement and the extent of invasion can be more precisely defined before treatment. It is truly a revolutionary procedure for determining-prior to surgery-the depth of invasion of a cancer located in the uterine body. 相似文献
892.
Eiji Ihara Atsushi Kurokawa Tomomichi Itoh Kenzo Inoue 《Journal of polymer science. Part A, Polymer chemistry》2007,45(16):3648-3658
As a novel synthetic strategy for copolymers of vinyl alcohol, we propose herein copolymerization of alkoxyvinylsilanes with other vinyl monomers, followed by oxidative cleavage of the alkoxysilyl groups attached to the main chain of the resulting copolymers. Radical copolymerization of di(isobutoxy)methylvinylsilane 1 with styrene afforded poly( 1 ‐ran‐styrene)s with a variety of compositions of both repeating units, although the Mn's (<9000) and yields (<35%) were rather low. The oxidative cleavage of the alkoxysilyl groups in the copolymers with m‐chloroperbenzoic acid proceeded efficiently, giving poly(vinyl alcohol‐ran‐styrene)s, which were soluble in common organic solvents. The structures of the poly(vinyl alcohol‐ran‐styrene)s were characterized by NMR, GPC, elemental analysis, and matrix‐assisted laser desorption time‐of‐flight mass spectrometry (MALDI‐TOF‐MS). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3648–3658, 2007 相似文献
893.
894.
Eiji Takahashi Fumio Sanda Takakazu Yamamoto Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2003,41(23):3828-3837
Novel N‐methylbenzothiazolium salts [N‐methyl‐2‐benzylthiobenzothiazolium, N‐methyl‐2‐(4‐nitrobenzylthio)benzothiazolium, N‐methyl‐2‐(1‐ethoxycarbonylethylthio)benzothiazolium, and N‐methyl‐2‐methylthiobenzothiazolium hexafluoroantimonates] were synthesized by the reaction of the corresponding 2‐substituted benzothiazole with dimethylsulfate, followed by anion exchange with KSbF6. These benzothiazolium salts cationically polymerized an epoxy monomer by photoirradiation. They also polymerized an acrylate monomer via a photoradical process. The use of aromatic compounds such as 2‐ethyl‐9,10‐dimethoxyanthracene as photosensitizers was effective in enhancing the polymerization. These benzothiazolium salts also served as thermal cationic initiators. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3828–3837, 2003 相似文献
895.
Katsuhiro Maeda Kazuhide Morino Eiji Yashima 《Journal of polymer science. Part A, Polymer chemistry》2003,41(22):3625-3631
Cis–transoidal poly[(4-carboxyphenyl)acetylene] (poly- 1 ) complexed with optically active amines and amino alcohols showed an induced circular dichroism (ICD) in the ultraviolet–visible region because of a predominantly one-handed helix formation in water and in dimethyl sulfoxide (DMSO). The Cotton effect signs of the poly- 1 /chiral amino alcohol complexes were inverted in the presence of water, whereas the ICD pattern of the poly- 1 /chiral amine complexes showed no change, regardless of the water content. These results demonstrated that the helix sense of poly- 1 induced by optically active amino alcohols through noncovalent acid–base interactions could be switched by changes in the solvent ratio in the DMSO–water mixtures. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3625–3631, 2003 相似文献
896.
Hiroshi Furuichi Nobuyuki FujiiYoshinori Kanno Eiji ItoHiroki Tanaka 《Journal of Non》2002,311(1):104-106
Transmission X-ray diffraction pattern taken from silicon sheared at 10 GPa revealed 8 halo rings. Their densest radii correspond to spacings of 308.4, 264.7, 187.2, 160.5, 152.8, 124.8, 104.9, and 91.5 pm, respectively. The ratios of these values correspond to those of interplanar spacings (1 1 1), (2 0 0), (2 2 0), (3 1 1), (2 2 2), (4 0 0), (3 3 1) and (4 2 0) of face-centered cubic (fcc) lattice. These facts suggest the formation of amorphous state based on fcc structure. This state remains at atmospheric pressure. 相似文献
897.
898.
899.
Tetsuji Sekitani Eiji Ikenaga Kenichiro Tanaka Kazuhiko Mase Mitsuru Nagasono Shin-ichiro Tanaka Tsuneo Urisu 《Surface science》1997,390(1-3):107-111
Auger-electron-photoion coincidence (AEPICO) studies of photon-stimulated ion desorption (PSID) for condensed acetonitrile induced by carbon core excitation have been performed to elucidate the desorption mechanism related to the Auger process. We have detected only the H+ ion in AEPICO spectra. The total ion yield spectrum divided by the total electron yield shows that the desorption efficiency is largely increased at the resonant excitation to C---H*. We have also measured the Auger electron spectrum and the AEPICO yield spectrum at the C---H* excitation. The AEPICO yield spectrum shows enhancement at 245–250 eV electron energy. This seems to be related to the spectator resonant Auger stimulated ion desorption. That is, H+ desorption is enhanced due to a two-hole-one-electron state at which the electron is in an anti-bonding C---H* orbital and the two holes can be in a 1π bonding orbital localized on the ---CH3 group. We have also measured similar spectra for other resonant excitation (π*CN, σ*CC, σ*CN). The results are discussed in connection with the bonding/anti-bonding character and localized character of the excited state. 相似文献
900.
Hideki Sakai Takahiko Kodani Atsuko Takayama Mamoru Nomura 《Journal of Polymer Science.Polymer Physics》2002,40(10):948-953
Changes in the minimum film‐formation temperature (MFFT) of 91:9 wt % vinylidene chloride (VDC)‐methyl methacrylate (MMA) latex prepared by the seeded batch process during storage at 5, 20, and 40 °C were investigated. MFFT of the latex rose the fastest at 20 °C. Infrared absorption of fresh and stored latexes and wide‐angle X‐ray diffraction of powder polymers obtained by lyophilization of fresh and stored latexes indicated a much greater increase in polymer crystallinity during latex storage at 20 °C than at 5 and 40 °C. Observed increases in MFFT during latex storage correlated with increases in polymer crystallinity. Infrared absorption of polymer stored at 5–60 °C in the dry state, such as lyophilized polymer and coating film, indicated that a polymer crystallinity increase was greater during storage at higher temperatures. These results showed that crystallization behavior of 91:9 wt% VDC‐MMA copolymer latex differed from that of VDC‐MMA copolymer in the dry state. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 948–953, 2002 相似文献