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21.
Many corporations move their manufacturing facilities or technologies from developed to developing countries. Stringent regulations have made it costly for industries to operate in developed, industrialized countries. In addition, labor costs are high in these countries, and there is increasing awareness among the general public of the health risks associated with industry. The relocation of hazardous industries to developing countries is driven by economic considerations: high unemployment, a cheaper labor force, lack of regulation, and poor enforcement of any existing regulations make certain countries attractive to business. The transfer of certain industries from Japan to Korea has also brought both documented occupational diseases and a new occupational disease caused by chemicals without established toxicities. Typical examples of documented occupational diseases are carbon disulfide poisoning in the rayon manufacturing industry, bladder cancer in the benzidine industry, and mesothelioma in the asbestos industry. A new occupational disease due to a chemical without established toxicities is 2‐bromopropane poisoning. These examples suggest that counter‐measures are needed to prevent the transfer of occupational health problems from a developed to a developing country. Corporate social responsibility should be emphasized, close inter‐governmental collaboration is necessary and cooperation among non‐governmental organizations is helpful. Am. J. Ind. Med. 52:625–632, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver.  相似文献   
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BACKGROUND AND AIMS: In South Africa diabetes makes a significant contribution to the burden of disease. Diabetic retinopathy is a leading cause of adult blindness, and screening can reduce the incidence. This project aimed to implement and evaluate a new service for retinal screening that uses a non-mydriatic mobile fundal camera in primary care. This is the first time such a service has been evaluated in an African primary care context. METHODS: The service was implemented as an operational research study at three community health centres and data were collected to evaluate the operational issues, screening, reporting and referral of patients. RESULTS: Out of 400 patients screened 84% had a significantly reduced visual acuity, 63% had retinopathy (22% severe nonproliferative, 6% proliferative and 15% maculopathy), 2% of eyes could not be screened and 14% of patients required dilatation. Referral was necessary in 27% of cases for cataracts, in 7% for laser treatment and in 4% for other specialist services. Repeat photography was needed in 8% and urgent follow-up in 12%. A SWOT analysis of the pilot project was completed and recommendations were made on how to integrate it into the district health system. CONCLUSION: Screening with a fundal camera improved the quality of care for diabetic patients and is feasible in the South African public sector, primary care setting. A single technician should be able to photograph almost 10,000 patients a year.  相似文献   
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Monoclonal antibodies directed against human, alpha-atrial natriuretic polypeptide (alpha-ANP; Human, 1-28) were obtained by somatic cell fusion between P3-X63-Ag8.653 myeloma cells and spleen cells from a BALB/c mouse immunized with human, alpha-ANP selectively coupled to keyhole limpet hemocyanin. From the analysis of polyclonal sera with respect to determinant specificity before the fusion, the strategy was primarily used to pick up monoclonal antibody specific for the N-terminal residues of human, alpha-ANP. Screening of antibodies in the hybridoma culture supernatants were performed by binding to iodinated synthetic human, alpha-ANP. Two stable clones producing anti-human, alpha-ANP antibodies, designated 13A1 and 10B1, were obtained by the limiting dilution technique. The ability of ANP(Rat, 1-28) to inhibit binding of 125I-human, alpha-ANP to these antibodies was almost equipotent to ANP(human, 1-28). However, ANP fragments (Human, 7-28) and (18-28) did not compete the binding completely. These results suggest that both 13A1 and 10B1 monoclonal antibodies can specifically recognized N-terminus of human, alpha-ANP, and may be a useful tool to investigate receptor binding of human, alpha-ANP by the antagonizing effect.  相似文献   
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Recently, we reported the production of three new monoclonal antibodies with high specificity for a Helicobacter pylori antigen suitable for diagnosis of H. pylori infection. The aim of the present study was to identify the antigen recognized by these monoclonal antibodies concerning both H. pylori and the feces of human subjects infected with H. pylori. The cellular antigen was purified from an H. pylori cell extract by immunoaffinity column chromatography with the monoclonal antibody as a ligand. The amino-terminal amino acid sequences (eight residues) of the purified antigen and H. pylori catalase were the same. The molecular weights of native and subunit, specific catalase activity, and UV and visible spectra of the purified antigen were in good agreement with those of H. pylori catalase. The human fecal antigens were purified from two fecal samples of two H. pylori-positive subjects by ammonium sulfate precipitation, CM-Sephadex C50 chromatography, and the same immunoaffinity chromatography used for the H. pylori cellular antigen. The fecal antigens had catalase activity. The amino-terminal amino acid sequences (five residues) of the human fecal antigen and H. pylori catalase were the same. The monoclonal antibodies reacted with the native cellular antigen, but did not react with the denatured antigen, human catalase, and bovine catalase. The results show that the target antigen of the monoclonal antibodies is native H. pylori catalase and that the monoclonal antibodies are able to specifically detect the antigen, which exists in an intact form, retaining the catalase activity in human feces.  相似文献   
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We investigated 361 patients with monoclonal gammopathy in whom immunoelectrophoresis was performed (1,037 tests) between 1986 and 2002 at Kagawa Prefectural Central Hospital. In this study, we identified 222 patients with monoclonal gammopathy of undetermined significance (MGUS). Malignant transformation of MGUS to multiple myeloma occurred in 15 patients (6.8%). No significant differences were observed in the means of total protein (TP), albumin (Alb), albumin/globulin ratio (A/G ratio), IgG, IgA, or IgM level in the initial examination between the patients who remained as MGUS and patients with malignant transformation of MGUS. However, the rate of progression to malignancy was high when the levels of normal immunoglobulins other than M protein were below the normal range. Since the number of MGUS cases detected and the number of protein fractionation performed were proportionate, and MGUS was found by protein fractionation in routine tests, protein fractionation is essential for detection of MGUS, and it is necessary to add serum protein fractionation to routine initial examination. In addition, long-term follow-up of patients with monoclonal gammopathy and preparation of a database of patient information are useful for monitoring the outcome.  相似文献   
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The aim of the present study was to investigate the roles of tyrosine kinase (TK) in the insulin action on cell volume in fetal rat (20-day gestational age) type II pneumocyte. Insulin (100 nmol/l) increased cell volume, and this insulin (100 nmol/l) action was completely blocked by 50 μmol/l bumetanide (BMT) and 10 μmol/l amiloride (AML). This observation indicates that 100 nmol/l insulin activates BMT-sensitive Na+/K+/2Cl? cotransporter and AML-sensitive pathways. The stimulatory action of 100 nmol/l insulin on BMT-sensitive Na+/K+/2Cl? cotransporter was completely abolished by 10 μmol/l lavendustin A (LAV-A, an inhibitor of TK), however 100 nmol/l insulin could stimulate AML-sensitive pathways even in LAV-A (10 μmol/l)-treated cells. These observations indicate that the insulin (100 nmol/l) action on the BMT-sensitive Na+/K+/2Cl? cotransporter is mediated through TK-dependent pathways, while 100 nmol/l insulin requires a TK-independent pathway to show the stimulatory action on the AML-sensitive pathways. From these observations we conclude that TK-dependent and -independent pathways are involved in the insulin (100 nmol/l) signaling in fetal rat type II pneumocyte.  相似文献   
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