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991.
T Hirota T Nishimaki T Suzuki S Komukai S Kuwabara K Aizawa K Hatakeyama 《Canadian Metallurgical Quarterly》1998,28(11):1160-1162
We report herein the rare case of a 65-year-old man found to have esophageal intramural metastasis from cancer of the gastric cardia. Endoscopic examination initially revealed an infiltrating ulcerative tumor of the gastric cardia involving the esophagogastric junction, as well as a submucosal tumor of the lower esophagus. A total thoracic esophagogastrectomy with lower mediastinal lymphadenectomy was performed, and the resected specimen demonstrated that both the cardia and esophageal tumors were adenocarcinomas with the same cellular differentiation. As lymphatic invasion and metastases to the paracardial and mediastinal lymph nodes were observed, the esophageal submucosal tumor was considered to be an intramural metastasis from the carcinoma of the gastric cardia resulting from extensive lymphatic spread. The patient died of recurrent disease 9 months after the resection. This case report serves to demonstrate that intramural metastasis may be a local indicator of the systemic spread of disease in patients with gastric carcinoma, as it is in esophageal carcinoma. 相似文献
992.
Changes in benzodiazepine binding sites labeled by [3H]flunitrazepan (FNZ) in twenty discrete brain regions of rats made tolerant to and dependent upon pentobarbital were examined. Animals were rendered tolerant by intracerebroventricular (i.c.v.) infusion with pentobarbital (300 micrograms/ 10 microliters/ hr for six days) through pre-implanted cannulae connected to osmotic mini-pumps. The pentobarbital dependence was assessed 24 hr after abrupt withdrawal from pentobarbital. In the tolerant rats, a significant increase in [3H]FNZ binding sites was found in layer IV of frontal cortex and the molecular layer of olfactory bulb. [3H]FNZ binding sites in the pentobarbital dependent rats were significantly increased in layers I-III and V-VI of frontal cortex, caudate-putamen, olfactory tubercle, globus pallidus and ventral pallidum, in addition to those observed in the tolerant group. There was, however, no significant difference in the hippocampus and several regions in the hindbrain in either pentobarbital-treated group. Taken together with characteristics of subtypes of benzodiazepine receptors and changes in GABA-benzodiazepine receptor complexes elucidated in our previous studies, these findings suggest that both types of benzodiazepine receptors are involved in the development of pentobarbital intoxication mediated by GABAA receptors. 相似文献
993.
Ultrafine oxide particles were synthesized by introducing aqueous solutions of metal salts into a high-temperature r.f. inductively
coupled plasma (the spray-ICP technique). The particles synthesized were spherical for ZrO2, Y2O3, Sm2O3, La2O3, δ-Al2O3, TiO2 (anatase), β-Bi2O3 and CuO, plate-like for Nd3O2, Cr2O3 and Pr2O3, polyhedral for PrO2, CeO2 and γ-Fe2O3, cubical for NiO, MgO, CaO, Co3O4 and Mn3O4, bar-like for SnO2 and ZnO, and foil-like for β-PbO and MoO3. The products of the alkaline earth group except for magnesium, were hydroxides and/or carbonates, spoiled by atmospheric
H2O and/or CO2. The particle morphology suggests that particle growth is controlled predominantly by the gas-solid reaction occurring on
the surface of nuclei condensed from the gas phase. Some of the oxides revealed a particle morphology characteristic of their
crystal structures. 相似文献
994.
T Nakaoka N Kojima T Hamamoto N Kurosawa YC Lee H Kawasaki K Suzuki S Tsuji 《Canadian Metallurgical Quarterly》1993,114(4):449-452
A calcium-independent phosphatidylserine specific binding protein detected on liposome blotting analysis was purified from rat brain and revealed to be identical to myristoylated, alanine-rich C kinase substrate (MARCKS). MARCKS specifically binds to phosphatidylserine but not phosphatidylcholine. The binding of MARCKS to phosphatidylserine was abolished on protein kinase C-dependent phosphorylation. Since bacterially expressed MARCKS also specifically binds to phosphatidylserine, myristoylation of the N-terminal glycine seems not to be essential for the binding of MARCKS to phosphatidylserine. These data suggest that phosphatidylserine is a membranous target molecule of MARCKS. 相似文献
995.
Microstructure characterization of sol-gel derived PZT films 总被引:1,自引:0,他引:1
The crystallization of sol-gel derived amorphous PZT films deposited on a MgO single-crystal substrate and a SiO2 glass substrate was examined. The pyrochlore crystallites, 5 nm in size, were homogeneously nucleated in the amorphous films at 350 °C. The nucleation temperature of pyrochlore did not depend on the type of substrate. Fine pyrochlore grains were stable even during annealing at high temperatures up to 600 °C. The perovskite formation temperature was dependent on the substrate, and was about 550 °C on the MgO single-crystal substrate and about 750 °C on the SiO2 glass substrate. The perovskite was heterogeneously nucleated preferentially at the substrate-film interface. Perovskite nucleation was more difficult at the SiO2 glass-film interface than at the MgO single crystal-film interface. The ease of nucleation reflected the perovskite formation temperature. Perovskite crystals grew fairly rapidly, once they were nucleated in the films. In the multiple-coated films, the interface between successive layers of PZT films was a favourable nucleation site of perovskite, and the columnar perovskite grains passing through the interface were often developed. 相似文献
996.
Urinary trypsin inhibitor (UTI) is a physiological protease inhibitor and inter-alpha-trypsin inhibitor (ITI) is regarded as a precursor of UTI. The purpose of this study is to determine the mechanism of the UTI release from ITI. To examine this, ITI was digested by human neutrophil elastase at various concentrations, and UTI-related proteins which were of the same size as UTI were obtained. The amino acid sequence of the 15 amino acid residues at the N-terminal of UTI-related proteins, corresponded to that of UTI. The amino acid sequences of the small amount of peptides detected corresponded to those of peptides from the heavy chain1 (H1) and the heavy chain2 (H2) of ITI, suggesting that most UTI-related proteins do not combine with peptides from the H1 and H2 of ITI. It was also revealed that UTI-related proteins have several physiological activities similar to those of UTI, i.e., human trypsin inhibitory activity, human neutrophil elastase inhibitory activity, inhibition of tumor necrosis factor-alpha (TNF-alpha) production from rat macrophages and of superoxide production from rabbit leukocytes. These results demonstrated that ITI is a precursor of UTI which is digested by human neutrophil elastase to release UTI, and that its elastase inhibitory activity is derived from UTI. 相似文献
997.
998.
Determination of cyanide in whole blood by capillary gas chromatography with cryogenic oven trapping
A Ishii H Seno K Watanabe-Suzuki O Suzuki T Kumazawa 《Canadian Metallurgical Quarterly》1998,70(22):4873-4876
Cyanide, one of the most important toxic substances, has been found measurable with high sensitivity by capillary gas chromatography (GC) with cryogenic oven trapping upon injection of headspace (HS) vapor samples. The entire amount of cyanide in the HS sample could be cryogenically trapped prior to on-line GC analysis. A 0.5-mL volume of blood in the presence or absence of cyanide and propionitrile (internal standard, IS) was added to a vial containing 0.25 mL of distilled water, 0.3 g of Na2-SO4, 0.2 mL of 50% H3PO4, and 0.1 g of ascorbic acid (when needed), and the mixture was heated at 70 degrees C for 15 min. A 5-mL volume of the HS vapor was introduced into a GC capillary column in the splitless mode at -30 degrees C oven temperature that was programmed up to 160 degrees C for GC analysis with nitrogen-phosphorus detection. A sharp peak was obtained for cyanide under the present conditions, and backgrounds were very clean. The extraction efficiencies of cyanide and IS were 2.89-3.22 (100 or 500 ng/mL) and 2.42%, respectively. The calibration curve showed good linearity in the range of 25-1000 ng/mL and the detection limit was approximately 2 ng/mL. The coefficients of intraday and interday variations were 2.9 and 11.8%, respectively. The mean blood cyanide level measured for actual fire victims was 687 +/- 597 ng/mL (mean +/- SD, n = 9). Endogenous blood cyanide concentration for healthy subjects was 8.41 +/- 3.09 ng/mL (mean +/- SD, n = 6). 相似文献
999.
1000.
S Shindo A Kojima K Iyori T Ishimoto M Kobayashi O Suzuki K Kamiya Y Tada 《Canadian Metallurgical Quarterly》1998,28(5):498-502
A 6-year prospective study of 80 abdominoplasties is reported. Type and incidence of complications are presented with particular attention toward the incidence of fluid collection following abdominoplasty, such as seroma and hematoma. Ultrasound was performed in 56 patients (70%), with normal findings in 27 patients (48%). Accurate diagnosis of fluid collection in 29 patients (51.8%), seroma in 24 (42.8%), and hematoma in 5 (9%) was confirmed with the aid of ultrasound. The advantage of early radiological diagnosis alerted the surgeon for positive findings of fluid collection areas in the abdominal wall, which resulted in close observation and early intervention whenever indicated. Ultrasound of the abdominal wall following abdominoplasty provides a noninvasive, accurate, and low-cost method of diagnosing fluid collection in the abdominal wall. This method, if performed routinely postabdominoplasty, will aid the surgeon in managing potential complications such as wound-healing problems, infection, and patient discomfort. 相似文献