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91.
Recently, corporate social responsibility (CSR) is becoming widely recognized as an issue for Japanese companies. Corporate responsibility for employees is considered important by various stakeholders, and occupational safety and health is regarded as one of these responsibilities. The present authors examined this issue from the viewpoint of corporate management by analysis of statements found in CSR-related reports. For companies listed on the First Section of the Tokyo Stock Exchange (TSE), we searched for CSR-related reports, and titles and contents, based on two established guidelines: the GRI Sustainability Reporting Guidelines 2002 as the international reference and the Environmental Reporting Guidelines of the Ministry of the Environment, Government of Japan, as the domestic reference. Corporations that published CSR reports were 26.3% (416/1,581) of the total, and large differences were recognized by type of industry. Comparing the numbers of pages for various contents, more concern was shown about the environment than about social activity, indicating the environment to be the main issue of CSR in Japan. In the items included in the guidelines, many matters about occupational accidents were mentioned, but it was found that statements regarding HIV/AIDS, which is not of such strong social concern in Japan, and statements regarding the costs of safety that are difficult to calculate were few. However, statements regarding mental health, which is of high interest socially, were many, even though this issue is not included in the two guidelines used. In revising the guidelines, these matters should be reviewed. In the future, continuance of analysis of CSR-related reports with regard to changes and comparisons with overseas reports will help improve occupational safety and health.  相似文献   
92.
The prognosis of patients with metastatic gastric cancer, particularly peritoneal carcinomatosis, remains poor despite intensive interventions. Gene therapy and hyperthermia can be promising strategies for such advanced disease. The study was conducted to explore the possible effective therapeutic approach of suicide gene therapy with herpes simplex virus thymidine kinase (HSV-tk) in combination with hyperthermia for advanced gastric cancer. The heat shock protein (hsp) 70B gene promoter-oriented HSV-tk (HSP-tk)/ganciclovir (GCV) system directed by heat shock was developed. Hsp promoter activity under the control of heating was assessed by dual luciferase assay in gastric cancer cell lines and implanted tumors of nude mice. In vitro cytotoxic assay was performed using the HSP-tk/GCV delivered by the hemagglutinating virus of Japan (HVJ) liposome, with or without heating. Mice with subcutaneously xenografted tumors and peritoneal carcinomatosis were treated with hyperthermia and gene therapy using the HVJ-liposome-carrying HSP-tk. Assessment by luciferase assay demonstrated highly inducible and tumor-specific promoter activity in vitro and in vivo. Cytotoxic assays showed that cells transfected with HSP-tk became more sensitive to GCV with heating. A synergistic effect was also observed when treated with a non-heat-inducible cytomegalovirus (CMV) promoter-mediated HSV-tk/GCV and heating, indicating bystander killing. The HVJ-liposome-carrying HSP-tk/GCV combined with hyperthermia significantly inhibited the growth of subcutaneous tumors and prolonged survival of mice with peritoneal carcinomatosis. We conclude that the combination of suicide gene therapy with hyperthermia can provide a promising treatment modality for advanced gastric cancer.  相似文献   
93.
Ferrimagnetic microspheres 20-30 microm in diameter are useful as thermoseeds for inducing hyperthermia in cancers, especially for tumors located deep inside the body. The microspheres are entrapped in the capillary bed of the tumors when they are implanted through blood vessels and heat cancers locally by their hysteresis loss when placed under an alternating magnetic field. In the present study, preparation of magnetite (Fe(3)O(4)) microspheres 20-30 microm in diameter was attempted by melting powders in high-frequency induction thermal plasma, and by precipitation from aqueous solution. The microspheres prepared by melting powders in high-frequency induction thermal plasma were composed of a large amount of Fe(3)O(4) and a small amount of wustite (FeO), and those subsequently heat treated at 600 degrees C for 1 h under 5.1 x 10(3) Pa were fully composed of Fe(3)O(4) 1 microm in size. The saturation magnetization and coercive force of the heat-treated microspheres were 92 emu g(-1) and 50 Oe, respectively. The heat generation of the heat-treated microspheres was estimated to be 10 Wg(-1), under 300 Oe and 100 kHz. The microspheres prepared by precipitation from aqueous solution consisted of beta-FeOOH, and those subsequently heat treated at 400 degrees C for 1 h in a 70% CO(2) + 30% H(2) atmosphere consisted of Fe(3)O(4) crystals 50 nm in size. The saturation magnetization and coercive force of the heat-treated microspheres were 53 emu g(-1) and 156 Oe, respectively. The heat generation of the heat-treated microspheres was estimated to be 41 Wg(-1), under 300 Oe and 100 kHz. The latter microspheres are believed to be promising thermoseeds for hyperthermic treatment of cancer.  相似文献   
94.
Pemphigus foliaceus is an autoimmune cutaneous disease with subcorneal acantholysis and pathogenic IgG4 autoantibodies directed against desmoglein 1. We present our experience with mycophenolate mofetil (MMF) in the treatment of one case of endemic pemphigus foliaceus (fogo selvagem) and two cases of the classic form. All patients had severe, refractory disease and developed marked adverse effects due to long-term corticosteroid therapy. MMF proved to be an effective corticosteroid-sparing agent at doses varying from 35 to 45 mg/kg/d. It was well tolerated, and we found no significant adverse effects from this drug.  相似文献   
95.
Craniofrontonasal syndrome (CFNS, OMIM 304110) is a distinctive genetic disorder whose main clinical manifestations include coronal synostosis, widely spaced eyes, clefting of the nasal tip and various skeletal anomalies. CFNS originally was thought to be transmitted as an autosomal dominant trait, but recent studies suggest that it is X- linked dominant, whereby all daughters of males are affected, whereas none of their sons are affected. Here we report data confirming that CFNS is X-linked, mapping to a 13 cM interval in Xp22 with a maximum two-point lod score of 3.9 (theta = 0) at DXS8022 and a multipoint lod score of 5.08 at DXS1224. Detailed phenotypic analysis shows that females are more severely affected than males, a highly unusual characteristic for an X-linked disorder. CFNS represents the first multiple congenital anomaly syndrome with this unusual phenotypic pattern of X-linked inheritance.   相似文献   
96.
We have previously found that glyceroneogenesis is very active in brown adipose tissue (BAT) and increases in fasted, diabetic and high-protein-diet-fed rats, situations of reduced thermogenic activity. To understand better the role of glyceroneogenesis in BAT glycerol-3-phosphate (G3P) generation, we investigated its activity during cold exposure (10 days at 4°C), a condition in which, in contrast to the above situations, BAT thermogenesis is markedly activated. Rates of total (from all sources) BAT fatty acid (FA) synthesis and rates of incorporation of glucose carbon into BAT glyceride-FA and -glycerol in vivo were markedly increased by cold exposure. Cold exposure induced a marked increase in BAT glyceroneogenic activity, evidenced by (1) increased rates of non-glucose carbon incorporation into glyceride-glycerol in vivo and of [1-14C]-pyruvate incorporation into glyceride-glycerol in vitro, and (2) a threefold increase in phosphoenolpyruvate carboxykinase activity. Most of the glyceride-glycerol synthesized by BAT via glyceroneogenesis or from glucose was used to esterify preformed FA. This use was markedly increased by cold exposure, in parallel with a pronounced activation of BAT lipoprotein lipase activity. In conclusion, during cold exposure BAT glyceroneogenesis is markedly activated, contributing to increase the generation of G3P, which is mostly used to esterify preformed FA.  相似文献   
97.
Bioactive titanium metal can be prepared by NaOH and heat treatments that present the metal with a graded bioactive surface layer of amorphous sodium titanate. This study used laser electrophoresis together with transmission electron microscopy (TEM) and energy-dispersive X-ray microanalysis (EDX) to relate the surface potential change of the bioactive titanium metal with its surface structural change in simulated body fluid (SBF). The surface potential of the metal was highly negative immediately after immersion in SBF. With increasing soaking time, the surface potential increased, revealing a maximum positive value, and then decreased to a constant negative value. TEM-EDX showed that immediately after immersion in SBF, the metal surface formed Ti-OH groups by exchanging Na(+) ions in the surface sodium titanate with H3O(+) ions in the fluid. Thereafter, with increasing soaking time the metal surface formed an amorphous calcium titanate, then an amorphous calcium phosphate, and, finally, apatite with bone-like composition and structure. These results indicate that the process of apatite formation on bioactive titanium metal is initiated by the formation of Ti-OH groups with negative charges that interact with calcium ions with positive charges to form calcium titanate. The calcium titanate gains a positive charge and later interacts with phosphate ions with negative charges, forming amorphous calcium phosphate. The amorphous calcium phosphate eventually transforms and stabilizes into bone-like crystalline apatite with a negative charge.  相似文献   
98.
A porcine hepatocyte based bioartificial liver (BAL) is still insufficient to replace liver transplantation. In this experiment, to strengthen the performance of a BAL, the effect of human recombinant hepatocyte growth factor (rhHGF) on the proliferation and function of xenogeneic porcine hepatocytes was studied. Isolated porcine hepatocytes were seeded at various densities (5 x 10(3) to 8 x 10(4) cells/well) on a collagen coated 96 well plate in Dulbecco's modified Eagle's medium (DMEM) with 10% FCS. After 4 hours, the medium was changed to DMEM with added insulin and dexamethasone. Subsequently, rhHGF was added at various concentrations (0, 0.625, 1.25, 2.5, 5, 10, 20, 40 ng/ml) and cultured for an additional 24, 48, and 72 hours, respectively. The proliferation of porcine hepatocytes in response to rhHGF reached a plateau at 2.5 ng/ml at 24 hours and subsequently decreased. The levels of porcine albumin vs protein present in the supernatant increased when cultured at high cell density. In conclusion, rhHGF was found to stimulate proliferation of porcine hepatocytes at low cell density and low concentration. rhHGF can also increase albumin synthesis at higher cell density, thus indicating its potential use in a more satisfactory porcine hepatocyte based BAL.  相似文献   
99.
Hydrolysis and polycondensation of triethoxysilane end-capped Poly (tetramethylene oxide) (Si-PTMO), tetraethoxysilane (TEOS), tetraisopropyltitanate (TiPT) and calcium nitrate (Ca(NO(3))(2)) gave transparent monolithics of PTMO-modified CaO-SiO(2)-TiO(2) hybrids. The samples with (TiPT)/(TEOS+TiPT) molar ratios from 0 to 0.20 under constant ratio of (Si-PTMO)/(TEOS+TiPT) of 2/3 in weight were prepared. It was found that the incorporation of TiO(2) component into a PTMO-CaO-SiO(2) hybrid results in an increase in the apatite-forming ability in a simulated body fluid: the hybrids with (TiPT)/(TEOS+TiPT) of 0.10 and 0.20 in mol formed an apatite on their surfaces within only 0.5 day. It seemed that, within the range of compositions studied, the TiO(2) content little affects the overall mechanical properties: Young's modulus were 52-55MPa, tensile strength, 7-9MPa, and strain at failure, about 30%. Thus, the organic-inorganic hybrids exhibiting both fairly high apatite-forming ability and high capability for deformation were obtained. These hybrid materials may be useful as new kind of bioactive bone-repairing materials.  相似文献   
100.
An ethylene-vinyl alcohol copolymer (EVOH) was treated with a silane coupling agent and calcium silicate solutions, and then soaked in a simulated body fluid (SBF) with ion concentrations approximately equal to those of human blood plasma. A smooth and uniform bonelike apatite layer was successfully formed on both the EVOH plate and the EVOH-knitted fibers in SBF within 2 days. Part of the structure of the resulting apatite-EVOH fiber composite was similar to that of natural bone. If this kind of composite can be fabricated into a three-dimensional structure similar to natural bone, the resultant composite is expected to exhibit both mechanical properties analogous to those of natural bone and bone-bonding ability. Hence, it has great potential as a bone substitute.  相似文献   
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