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661.
A case of primary small cell carcinoma of the esophagus in which extensive hormonal studies could be performed is reported. The tumor was considered as a neuroendocrine tumor because the tumor cells showed intracytoplasmic argyrophilia, neurosecretory granules, and positive stain for neuron-specific enolase with Grimelius stain, electron microscopy, and immunohistochemistry, respectively. Furthermore, the tumor was regarded as a gastrin-producing tumor because of positive stain for gastrin in the tumor cells. The present case is the first case of primary small cell carcinoma of the esophagus with ectopic gastric production.  相似文献   
662.
The interaction between the respiratory pathogen Bordetella bronchiseptica and epithelial cells was studied. After 2-3 h, B. bronchiseptica strains exerted a strong cytotoxic effect on HeLa cells which was evident by rounding of the cells and detachment from the substrate and which ultimately resulted in total disintegration of the host cell. Production of this cytotoxic activity appeared to be regulated by the BvgAS sensory transduction system, which coordinately regulates many B. bronchiseptica virulence factors, since bacteria cultured in the presence of sulfate anions, inhibitors of the BvgAS response, did not exhibit this effect. Furthermore, spontaneous phase variants of B. bronchiseptica strains adhered to HeLa cells but were not cytotoxic. The cytotoxic component is presumably not secreted because the bacterial culture supernatant was not cytotoxic for HeLa cells. Besides HeLa cells other human epithelial cell lines such as Chang cells, larynx HEp-2 cells and lung NCI-H292 cells were sensitive to the cytotoxic activity of B. bronchiseptica. These results suggest the presence of a novel BvgAS-regulated virulence factor in B. bronchiseptica.  相似文献   
663.
Mizoribine, a novel immunosuppressive agent developed in Japan, was administered as a monotherapy to a systemic lupus erythematosus (SLE) patient with the clinical symptoms and immunological abnormalities accompanying SLE showing marked improvement. The result of prolonged administration over 22 months in this case showed neither relapse nor side-effects. Reports have been made about mizoribine used concomitantly with steroids in the treatment of SLE; however, there have not been any reports of mizoribine as a monotherapy for SLE being effective. In this case, mizoribine (150 mg/day) was administered without steroids as a monotherapy on a outpatient basis since the patient's condition overall was relatively good and the serious complications of the heart, kidneys, and lungs that accompany SLE were not observed. The results of this treatment showed improvements in alopecia, arthritis, and systemic malaise from about the 4th week after the start of administration, and the clinical symptoms that accompany SLE had completely disappeared in the 8th week. Also, the immunological tests markedly improved. Four months after the start of administration the immunological abnormalities in the anti-DNA antibody, rheumatoid factor, and immune complex were completely corrected. This case showed dramatic improvement in the SLE clinical symptoms and immunological abnormalities with the mizoribine monotherapy as well as the potential for mizoribine monotherapy to maintain a state of remission over the long term.  相似文献   
664.
A protein monolayer of bovin serum albumin (BSA) was stabilized at the air- water interface using glutaraldehyde (GA). The GA-treated BSA film was transferred onto the glass surface, followed by immunochemical lamination of anti-BSA antibody. Protein A-β-galactosidase (pro A-β-gal) conjugate was then reacted with the antibody molecular layer. Biofunctional protein films can be prepared on the BSA base Langmuir-Blodgett film by intermolecular complementary affinity between the proteins concerned.  相似文献   
665.
Polyacetylene films were characterized as an electrode material in aqueous solutions. The trans polyacetylene films behaved as electrodes under reducing conditions. Oxygen gas evolution was greatly retarded under oxidizing conditions, primarily due to the high reactivity with oxygen. Visible light illumination resulted in a positive shift in electrode potential. The electrode developed photopotential reversibly in accord with illumination. The polyacetylene electrode gave cathodic photocurrent when contacted with a deoxygenated acetate buffer. The cathodic photocurrent increased with decreasing pH, ranging from 0 to 5.5 × 10?6 A/cm2. The possible use of polyacetylene electrodes for photoenergy conversion is discussed.  相似文献   
666.
In an earlier paper, we argued that Fodorian Semantics has serious difficulties. However, we suggested possible ways that one might attempt to fix this. Ted Warfield suggests that our arguments can be deflected and he does this by making the very moves that we suggested. In our current paper, we respond to Warfield's attempts to revise and defend Fodorian Semantics against our arguments that such a semantic theory is both too strong and too weak. To get around our objections, Warfield proposes a modified reading of one of Fodor's conditions and proposes adding a new condition to the theory. We show that neither the modified reading nor the additional condition saves the asymmetric causal dependency approach to naturalized semantics.  相似文献   
667.
Ultrafine aluminum carbide (Al4C3) powders with crystallite sizes of <40 nm were prepared by the pyrolyses of alkylaluminums, i.e., trimethylaluminum (Al(CH3)3: TMAL), triethylaluminum (Al(C2H5)3: TEAL), triisobutylaluminum (Al(i-C4H9)3: TIBAL) at a temperature between 950° and 1100°C. Although the pyrolysis of TMAL produced Al4C3 at 950°C, the pyrolysis temperature of TEAL to produce Al4C3 was raised up to 1100°C. The pyrolysis of TIBAL at 1100°C produced not only crystalline Al4C3 but also amorphous oxycarbide. The TEAL-derived powder had the highest true density (2.89 g.cm−3 or 97% of the theoretical density) among the three kinds of powders.  相似文献   
668.
Gas sensors generally consist of two major components: a gas recognition element which provides the specificity and selectivity of the measurement and a physical transducer which translates the gas absorption or desorption event into electronic signal. In this paper, plasma polymerized allylamine (PPAa) film is used as a gas recognition element and a surface transverse wave (STW) device is used as a physical transducer. It is confirmed that STW sensor devices coated with PPAa films provide high sensitivity for moisture. The STW sensor device with a 63 nm PPAa film provided twenty four times higher sensitivity than that of a non-coated STW device. In addition, the chemical structure of PPAa films is characterized by the FT-IR and the contact angle measurement.  相似文献   
669.
We constructed an integrated immunosensor system to combine a quartz crystal microbalance with the agglutination reaction of immunized latex beads. C-reactive protein (CRP) induced an immunoreaction due to the latex bends with anti-CRP antibody. We succeeded in determining the concentration of CRP necessary in human serum for disease diagnosis using a CRP Sensor I.  相似文献   
670.
Cotton wool-like poly(l-lactic acid) and siloxane-doped vaterite (SiV) composite scaffolds were prepared with a modified electrospinning system for bone tissue engineering applications. The effects of changing the SiV content in the materials from 10 to 30 wt% on elasticity and the ability to release calcium ions and soluble silica were evaluated. The elasticity of the cotton wool-like composites was almost the same as that of the PLLA from the results of compressibility and recovery tests. The materials released calcium ions for more than 56 days and soluble silica for 28–56 days in a tris buffer solution (pH 7.4). Mouse osteoblast-like cells (MC3T3-E1 cells) were cultured on/in the cotton wool-like materials or the fibremats out of the same composite materials as that used for the cotton wool-like materials. The cells penetrated into and proliferated inside the cotton wool-like materials, although they mainly adhered on the fibremat surface.  相似文献   
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