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941.
Forty-three primary mediastinal tumors or cysts were surgically treated in 41 patients during a 10-year period. These tumors consisted of 20 thymic tumors, 10 neurogenic tumors, 5 teratomas, 3 lymphoid tumors, 2 congenital cysts, 2 mediastinal thyroid tumors, and 1 chondroma. There were 16 male and 25 female patients. The mean age was 44 years with a range of 6 to 79 years. Sixteen patients (39%) were symptomatic. There were 20 thymic tumors including 13 thymomas, 5 thymic cysts, and 2 hyperplasia with myastenia. Additional radiation therapy was recommended for all but stage I thymomas. Only 1 of the 10 neurogenic tumors was malignant. Eight teratomas were all cystic and matured. Early operative intervention is mandatory in these cases.  相似文献   
942.
The phenotype of peripheral blood mononuclear cells (PBMC) was examined in 13 healthy volunteers, 26 HTLV-I carriers, and 58 ATL patients (22 smouldering, five chronic, 24 acute, and seven lymphoma type). The percentage of CD4+, CD25+, CD28+ and CD45RO+ cells in the PBMC of the chronic and acute type patients was significantly higher than that of the volunteers, whereas the percentage of CD8+ and CD45RA+ cells in these patients was significantly low. The histogram for CD45RO fluorescence intensity (FI) revealed two patterns: pattern A consisted of CD45RO+ cells with high FI (CD45ROhigh) and intermediate FI (CD45ROint). Pattern B consisted exclusively of CD45ROhigh. Pattern A was evident in all volunteers. The percentage of subjects showing pattern B was increased in an order that reflected disease progression. In the patients with pattern A, the CD45ROint cells were CD4+ and CD8-, and the FI of CD2, CD3, and Fas within the CD45ROint cells appeared to be lower than that within the CD45ROhigh cells. The acute type patients with pattern A had a significantly longer survival curve than that of these patients with pattern B. These results suggest that the presence of CD45ROint cells may be related to protection against disease progression in HTLV-I-infected individuals.  相似文献   
943.
To achieve the stabilization of greenhouse gas (GHG) concentrations in the atmosphere, the international community will need to intensify its long-term efforts. Many EU countries have released national long-term scenarios toward 2050, and their ambitious targets for CO2 emission reduction are aiming at a decrease of more than 50% of today's emission. In April 2004, Japan began a research project on its long-term climate policy. This paper discusses the long-term scenarios in other countries and the medium-term scenarios in Japan to support the development of a Japan's long-term climate stabilization scenario. In this study, CO2 emission is decomposed with an extended Kaya identity (indexes: CO2 capture and storage, carbon intensity, energy efficiency, energy intensity, economic activity) and a Reduction Balance Table is developed.  相似文献   
944.
The fatigue strength of centrifugally cast spheroidal graphite (SG) iron pipe was investigated. A parallel series of tests were carried out both on plain plate specimens which were extracted from an iron pipe, and on notched iron specimens. These results were compared with results for rolled steel beams, which were made from a steel with a tensile strength similar to the SG iron [1]. It was found that the strengths at a life of 2 × 106 cycles differed only by 20% between the SG iron pipe and the rolled steel beam, whereas those of plain plate specimens of the two materials differed by 38%. The fatigue failure in the SG iron pipe initiated from the inherent gas pores existing in the inner surface of the pipe, while the fracture in the rolled steel beams originated from external notch defects. Thus, the steel beam appeared more sensitive to the external notches than the SG iron pipe, when the notch size was smaller than 1 mm. However, it was revealed from the fatigue tests on notched plates that, as the notch became severer, the fatigue strength of SG iron became more affected by the notches than did that of the steel. A fracture mechanics analysis indicated that this was because the fatigue crack growth rate for SG iron was three times as high as that for steel.  相似文献   
945.
Detection of genetically modified organisms obtained from food samples   总被引:2,自引:0,他引:2  
Genetially modified organisms (GMOs) were explored in food samples obtained from November 2000 to March 2003 in the Tokyo area by using PCR and real-time PCR techniques. The existence of Roundup Ready Soybean (RRS) was surveyed in processed foods derived from soybeans, such as tofu, boiled soybean, kinako, nama-age, abura-age, natto, miso, soymilk and yuba. RRS was detected in 3 of 37 tofu, 2 of 3 nama-age, 2 of 3 yuba and 3 of 3 abura-age samples. The CBH351 in 70 processed corn foods, NewLeaf Plus and NewLeaf Y in 50 processed potato foods, and 55-1 papaya in 16 papayas were surveyed. These GMOs were not detected among the samples. Qualitative and quantitative analyses of RRS and genetically modified (GM) corn were performed in soybean, corn and semi-processed corn products such as corn meal, corn flour and corn grits. RRS was detected in 42 of 178 soybean samples, and the amount of RRS in RRS-positive samples was determined. The content was in the range of 0.1-1.4% in identity-preserved soybeans (non-GMO), and 49.8-78.8% in non-segregated soybeans. On the other hand, GM corns were detected in 8 of 26 samples. The amount of GM corn in GM corn-positive samples was in the range of 0.1-2.0%.  相似文献   
946.
A 63-year-old man with smoldering adult T-cell leukemia (ATL) which became acute was admitted. During chemotherapy, he experienced epigastric pain and fever due to neutropenia. The combination therapy of antimicrobials and rhG-CSF was ineffective and he died. Autopsy revealed systemic invasion of ATL cells. The stomach findings resembled those of phlegmonous gastritis, a rare form of bacterial gastritis, along with diffuse, mucosal necrosis with hemorrhage. The pathogenesis of necrotizing gastritis remains to be elucidated. The patient had also received histamine H2 antagonist for gastric ulceration, which might have influenced the gastric bacterial flora.  相似文献   
947.
The cover gas entrainment at the free surface of sodium coolant becomes one of the significant issues according to the compact sizing of reactor vessel in the latest reactor design. In the present study, some basic experiments for the gas entrainment due to the surface vortex were performed in order to obtain the fundamental knowledge about the entrained bubble size. Distributions of entrained bubble diameters in several experimental conditions were obtained from bubble images using an image processing technique. Velocity fields around vortices and surface dimple shapes (gas cores) due to surface vortices were measured to grasp those influences on bubble shapes. The result showed that mean equivalent diameters of bubbles were varied from 1.3 to 2.1 mm in the range of present experimental conditions. The bubble sizes were influenced by the thickness of gas core.  相似文献   
948.
The carbonization properties of pyrene hydrogenated by Birch reduction to a variable extent were studied at 600°C under atmospheric pressure, in order to examine the influence of partial hydrogenation on the carbonization reactivity. Pyrene, which did not yield any coke, produced coke with flow texture after partial hydrogenation. Carbon yield of partially hydrogenated pyrene sharply depended on the hydrogenation extent. The intermediate stage of the carbonization pursued by hot-stage microscopy followed the steps of nucleation, growth and coalescence of anisotropic sphere. Considerable fluidity was observed at the final stage of mesophase development prior to the complete solidification where the benzene insoluble content exceeded 90%. The carbonization mechanism was discussed from the view of the polymerization of hydrogenated pyrene in relation with its structure.  相似文献   
949.
The butylamination of 1-aminohalogenoanthraquinones was promoted by both copper and cobalt ions. In the presence of cobalt(ii) chloride the butylamination of 1-amino-4-bromo-(2b) or 1-amino-2,4-dibromo-anthraquinone(2j) proceeded smoothly even at ambient temperature to give the corresponding butylaminated products. It is proposed that the formation of a metal complex(1), in which the 1-aminoanthraquinone moiety coordinates with the metal ion, facilitates the amination.  相似文献   
950.
InP/GaInAsP buried heterostructure (BH) lasers for the 1.5 ?m region have been fabricated on semi-insulating InP substrates. The threshold current of the lasers is as low as 38 mA under CW operation at 25°C, which is nearly the same as for BH lasers fabricated on n-type InP substrates.  相似文献   
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