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81.
Engineering liver tissue constructs with sufficient cell mass for transplantation implies culturing large numbers of hepatocytes in a reduced volume; however, providing sufficient oxygen to dense cell cultures is still not feasible using only conventional culture medium. Liposome-encapsulated hemoglobin (LEH), an oxygen-carrying blood substitute originally designed for short-term perfusion, may be a good candidate as an oxygen carrier to cultured liver cells. In this study, we investigated the feasibility of maintaining long term hepatocyte cultures using LEH. Primary fetal and adult rat liver cells were directly exposed to LEH for 6 to 14 days in static culture or in a perfused flat plate bioreactor. The functions and viability of adult rat hepatocytes exposed to LEH were not adversely affected in static monolayer culture and were even improved in the bioreactor. However, some cytotoxicity of LEH was observed with fetal rat liver cells after 4 days of culture. LEH, though a suitable oxygen carrier for long-term culture of mature hepatocytes, is not suitable in its present form for perfusing fetal hepatocyte cultures in direct contact with the liposomes; either the LEH will have to be made less toxic or a more sophisticated bioreactor that prevents the direct contact between hepatocytes and perfusates will have to be designed if fetal cells are to be used for liver tissue engineering.  相似文献   
82.
The interaction of co-polymers of vinylpyrrolidone-vinylacetate with anionic surfactants, such as lithium dodecyl sulfate (LiDS), lithium perfluorooctane sulfonate (LiFOS) in aqueous solution, has been studied. When the content of vinylacetate in the co-polymers increases, reduction in the surface tension of co-polymers alone becomes significant. In mixtures of co-polymers and surfactants, co-polymer-LiFOS complexes are formed at lower surfactant concentration than that of co-polymer-LiDS. The micropolarity of the co-polymers-surfactant complexes depends on the composition of co-polymers and is higher for co-polymer-LiFOS than that for co-polymer-LiDS. Further, the solubilization behavior of α-(o-tolylazo-)-β-naphthylamine (Yellow OB) (Tokyo Kasei Co., Ltd., Tokyo, Japan) in the co-polymer-surfactant complexes is almost independent of the co-polymer composition, but different from the surfactants, where a very low solubilized amount of Yellow OB is observed for co-polymer-LiFOS.  相似文献   
83.
Novel brominated and halogen-less azaphilone (oxoisochromane) derivatives, 5-bromoochrephilone and dechloroisochromophilone IV, and known derivatives, dechloroisochromophilone III and isorotiorin, were isolated from the culture broth of a producing organism of isochromophilones I and II (azaphilones inhibiting gp120-CD4 binding), Penicillium multicolor FO-2338, fermented in a medium containing potassium bromide. Nineteen azaphilone-related compounds isolated from the above strain and from other fungi were tested for the inhibition of gp120-CD4 binding and the structure-activity relationship is discussed. Consequently, 5-bromoochrephilone is the strongest inhibitor (IC50, 2.5 microM). A halogen atom at C-5, a proton at C-8 and a diene structure in C-3 side chain of 6-oxoisochromane ring are necessary for gp120-CD4 binding.  相似文献   
84.
A 71-year-old man was admitted to our hospital with massive GI bleeding and followed by acute myocardial infarction. Severe three vessel coronary artery disease with poor left ventricular performance (EF: 40%) was demonstrated by coronary angiography. He was referred for CABG. He had also cholecystitis, which needed surgical treatment simultaneously. Combined CABG and cholecystectomy were performed without using gastroepiploic artery as a bypass graft, and through separate median sternotomy and through right upper transrectal laparotomy. Postoperative course was uneventful. This combined procedure is beneficial for the patients with acute cholecystitis and unstable angina.  相似文献   
85.
The purpose of our work is to control the interfacial bonds between PVC and NBR using the ammonium salts of triazine thiols and dithiodimorpholine (DTDM) and thereby reveal the relation between the interfacial bonds and the final mechanical properties of products. In the experimental work a two-stage process was used. At first, an NBR/PVC blend was mixed with a mono-tetra-n-butylammonium salt of triazine trithiol at a temperature of 100°C on a two-roll mill to give the branching structure of triazine thiols into PVC. In the second stage branched NBR/PVC reacted with DTDM to afford the branched PVC containing trithiomorphonyl groups. In the presence of ZnO at 160°C trithiomorphonyl groups react with NBR to form a crosslinking structure between NBR and PVC. The mechanical properties of cured NBR/PVC blends were markedly improved by the treatment process and after addition of tetramethylthiuram monosulphide also. The mechanical properties were not improved by increasing the concentration of TT-TBA (tetrabutylammonium salt of 1,3,5-triazine-2,4,6-trithiol) over 4.2 phr.  相似文献   
86.
87.
At the Japan Atomic Energy Research Institute (JAERI), research activities related to probabilistic fracture mechanics (PFM) have been conducted as a part of the research program on aging and structural integrity of LWR components. This paper describes the outline of two activities related to PFM, i.e. the development of a PFM code and a contract research on ‘Application of PFM Methodology to Reliability Assessment of Nuclear Components’ implemented by the Japan Welding Engineering Society (JWES). In the former research, a new PFM code PASCAL (PFM Analysis of Structural Components in Aging LWR) was developed. This code has some new functions in models of semi-elliptical crack extension, elastic–plastic fracture analysis based on R6 method and options for the evaluation of overlay cladding and warm pre-stress (WPS) effect. Besides, the code has the function to evaluate the effect of irradiation embrittlement recovery by thermal annealing of a reactor pressure vessel and re-irradiation embrittlement. Based on the analyses on benchmark problem conducted by USNRC/EPRI, performance and functions introduced in the code were examined. Some case studies were also carried out to investigate the influence of various parameters. On the other hand, JAERI has been sponsoring the PFM related activities in relation to the structural integrity of LWR components. These activities have been conducted at JSME and JWES. The objective of this activity has been to provide for the future need of PFM methodology.  相似文献   
88.
Fibrolamellar carcinoma of the liver (FLC), which is very rare in Japan, is reported to be frequently accompanied by lymph node metastasis in Europe and the United States. We describe a 22-year-old man with recurrent FLC in the lymph nodes after undergoing partial hepatectomy. He underwent a second operation for removal of recurrent lymph node tumors in the mediastinum and abdominal cavity one year after initial surgery. However, a third operation became necessary seven months later, because of recurrence in a lymph node in the abdominal cavity. We discuss the management of lymph node metastasis from FLC.  相似文献   
89.
90.
Abstract— The perfluorocarbons (PFCs) used as etching‐process and chamber‐cleaning gases in the manufacture of LCD devices have a high global‐warming potential and a long atmospheric lifetime. Thus, to voluntarily reduce these environmentally harmful PFCs, in 2001 the Japanese LCD association established the World LCD Industry Cooperation Committee (WLICC), together with its counterpart associations in the Republic of Korea and Taiwan. Since that time involving many discussions, the WLICC reached a consensus on reducing the aggregate absolute PFC emissions to the equivalent of less than 0.82 million metric tons of carbon by 2010. Each association has been taking whatever emission reduction steps it considers best to achieve this goal. Thanks to these measures, the PFC emissions from the Japanese LCD industry have remained at the same level, or less, than those of the year 2000, in spite of the fact that PFC purchases have continually increased. In the interim, the Japanese LCD association has been obtaining experimental data for the 2006 IPCC Inventory Guidelines, which will give the emission factors needed to estimate the PFC emissions. As a result, some data are quite different from emission factors given in the current 2000 Inventory Guidelines. All the data obtained have been submitted to the IPCC to be adopted in the new 2006 Guidelines.  相似文献   
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