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51.
In a consecutive series of 146 patients with hepatocellular carcinoma (HCC), 10 patients (6.8%) were found to have one or two extrahepatic malignancies (EHM). Of these, eight had double cancers and two, triple cancers. The associated malignancies included eight cases of gastric cancer and four cases of colon cancer. Among the 12 lesions, eight were in the early stage. All the 10 patients were hepatitis B surface antigen negative. The incidence of coexisting liver cirrhosis and the retention rate of indocyanin green in 15 minutes among HCCs with EHM were significantly lower than those among HCC alone. These results suggest that the etiology of HCC with EHM is different from the etiology of HCC alone in Japan.  相似文献   
52.
What are the effects of a word's orthographic neighborhood on the word recognition process? S. Andrews (1989) reported that large neighborhoods facilitate lexical access (the neighborhood size effect). J. Grainger, J. K. O'Regan, A. M. Jacobs, & J. Segui (1989) reported that higher frequency neighbors inhibit lexical access (the "neighborhood frequency effect"). Because neighborhood size and neighborhood frequency typically covary (words with large neighborhoods will usually possess higher frequency neighbors), these findings would seem to contradict one another. In the present study, 6 experiments on the effects of neighborhood size and neighborhood frequency indicated that, at least for low-frequency words, large neighborhoods do facilitate processing. However, the existence of higher frequency neighbors seems to facilitate rather than inhibit processing. The implications of these findings for serial and parallel models of lexical access are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
Coal hydrogenation products, Athabasca tar sand bitumen, and Green River shale oil produced by retorting were analyzed by the Brown—Ladner method and the Takeya et al. method on the basis of elemental analysis and 1H-NMR data, by 13C-NMR spectroscopy and by FT-IR spectroscopy. Structural characteristics were compared.The results show that the chemical structure of oils from Green River shale oil and Athabasca tar sand bitumen, and the oils produced in the initial stage of hydrogenation of Taiheiyo coal and Clear Creek, Utah, coal is characterized as monomers consisting of units of one aromatic ring substituted highly with C3–6 aliphatic chains and heteroatom-containing functional groups. The chemical structure of asphaltenes from Green River shale oil and Athabasca tar sand bitumen is characterized by oligomers consisting of units of 1–2 aromatic rings substituted highly with C3–5 aliphatic chains and heteroatom-containing functional groups. The chemical structure of asphaltenes from coal hydrogenation is characterized by dimers and/or trimers of unit structures of 2 to 5 condensed aromatic rings, substituted moderately with C2–5 aliphatic chains and heteroatom-containing functional groups.The close agreement between fa(1H-NMR) and fa(13C-NMR) for Green River shale oil derivatives and Athabasca tar sand derivatives indicates that the assumption of 2 for the atomic H/C ratio of aliphatic structures is reasonable. For coal hydrogenation products, a value of 1.6–1.7 for the H/C ratio of aliphatic structures would be more reasonable.  相似文献   
54.
X-Prolyl dipeptidyl-aminopeptidase (no EC no. assigned) activity in normal and pathological human sera was assayed with several newly synthesized X-proline p-nitroanilides as chromogenic substrates. Normal values for 88 healthy subjects (15 to 81 years old), with glycylproline p-nitroanilide as substrate at pH 8.7, were 54.9 +/- 1.5 (SE) (range, 25.7 - 96.0) mumol/min per liter of serum at 37 degrees C. The results suggest that the enzyme activities with all X-proline p-nitroanilides were increased in patients with hepatitis and decreased in patients with gastric cancer. On Sephadex G-200 column chromatography, normal human sera showed a single peak of enzyme activity with glycylproline p-nitroanilide as the substrate, which coincided with the peak with glycylproline beta-naphthylamide but was different from the peaks with leucine beta-naphthylamide. Sera from patients with hepatitis or liver cirrhosis showed an increase in the normal peak and the appearance of another new peak with glycylproline p-nitroanilide as substrate.  相似文献   
55.
A ceramics acid, calcined at temperatures above 1000 °C, was obtained by impregnating aluminum hydroxide with aqueous ammonium metatungstate followed by calcining in air at 1000–1200 °C (1–5 wt% W); its acidity and catalytic activity for decompositions of toluene, ethylbenzene, and cumene are higher than those of silica-alumina.  相似文献   
56.
LB heterofilms of double layer consisting of arachidic acid and 2-pentadecyl-7, 7′, 8, 8′-tetracyanoquinodimethane (C15 · TCNQ) LB films were sandwiched between Al and Au thin evaporated films. Such layer structures of Al/LB heterofilm/Au were deposited on the SiO2 insulating film of silicon wafters. Resistance in the surface direction of the above layer structure was measured by the four-point probe technique. As a result, very low resistance of 10?2 ~ 10?3 Ω was obtained by the electrode system of gap 3.3 mm with width 10 mm. It was clarified in the experiments that the current flowed through the LB heterofilms of about 200 ~ 30 Å in thickness; accordingly the resistivity of LB heterofilms was calculated to be 10?8 ~ 10?9 Ω cm. Such a value of resistivity was much smaller than the metal resistivity of 10?5 Ω cm. Furthermore, the current through the LB film, increased up to 1.3A, was equivalent to the very high current density of 4.1 ~ 105 A/cm2. However, the resistance was increased suddenly by 106 times at that time and the current was decreased to 3 ~ 10?4 A. Such a switching phenomenon could be observed repeatedly. The ultraflow resistance and the very high current density observed in the LB heterofilms will be explained by the model of the potential well filled with electron gas which was generated in the LB hetero-film by the polarization of C15 · TCNQ LB film.  相似文献   
57.
Regulation of GH secretion from phytohemagglutinin (PHA)-stimulated lymphocytes was investigated in six normal subjects. Peripheral blood mononuclear cells were incubated with PHA (10 micrograms/mL) in the presence of various amounts of recombinant human GH (0-100 ng/L) and/or recombinant human insulin-like growth factor-I (0-1000 micrograms/L), and the secreted GH was measured by a highly sensitive enzyme immunoassay. PHA-stimulated lymphocytes secreted immunoreactive GH in all subjects (13.6 +/- 2.4 ng/L). Exogenous GH up-regulated the GH secretion in a dose-dependent manner, while IGF-I did not affect either basal GH secretion or the up-regulation by exogenous GH. These findings suggest a difference in the regulation of GH secretion between endocrine and immune systems.  相似文献   
58.
We and others have demonstrated that a mutation in Tsc2 is the rate-limiting step for renal carcinogenesis in the Eker rat model. Although inactivation of Tsc2 results in development of renal tumors, it is not sufficient for metastatic renal cell carcinomas (RCs) in the Eker rat. To investigate the additional genetic event(s) necessary for cancer metastasis, we have established highly metastatic S-Lk9d-SLM cell lines from a non-metastatic RC cell line (Lk9dL) by co-implantation with a foreign body (gelatin sponge). Since these cell lines were remarkably different in metastatic performance (all and none, respectively) despite having the same genetic background, they should be useful experimental tools to investigate metastasis-promoting events in renal carcinogenesis.  相似文献   
59.
Various countries have established regulations that stipulate the labeling of agricultural commodities, feed, and food products that contain or are made from genetically modified (GM) material or that contain adventitious GM material in amounts that exceed certain threshold levels. While regulations in some countries refer to GM material on a weight per weight (w/w) percentage, the currently applied detection methods do not directly measure the w/w percentage of the GM material. Depending on the particular method and the sample matrix it is applied to, the conversion of analytical results to a w/w percentage is challenging or not possible. The first rapid PCR system for GM maize detection on a single kernel basis has been developed. The equipment for the grinding of individual kernels and a silica membrane-based 96-well DNA extraction kit were both significantly revised and optimized for this particular purpose, respectively. We developed a multiplex real-time PCR method for the rapid quantification of GM DNA sequences in the obtained DNA solutions. In addition, a multiplex qualitative PCR detection method allows for the simultaneous detection of different GM maize traits in each kernel and thereby for identification of individual kernels that contain a combination of two or more GM traits. Especially for grain samples that potentially contain combined-trait GM maize kernels, the proposed methods can deliver informative results in a rapid, precise, and reliable manner.  相似文献   
60.
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