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The authors studied oncologic mortality among the workers exposed to some acryl monomers. The oncologic risk was estimated for the individuals exposed to acrylonitrile, methyl methacrylate, methyl- and butyl acrylate, methacrylic acid. Occurrence of the malignancies appeared to depend on the dose of methyl methacrylate.  相似文献   
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Management of chronic pain is now not only medical but a very important social and economic problem. The approaches to its management in specialized pain control centers are discussed basing on the 20-year experience of the first such center in Russia: pain control clinic with therapeutic and diagnostic center "Integrative Medicine" at Research Center of Surgery. The problems of personnel for such pain control centers, cost-effect issues, diagnostic and therapeutic methods including an advanced technique, resonance electropuncture analgesia and therapy, are reviewed.  相似文献   
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Regardless of the primary care model used in the long-term care facility, each of the three approaches offers quality care improvement and greater consistency for residents at reduced costs. Of the three, an all licensed nursing staff model could best meet the higher acuity levels of residents and the disintegrating availability of qualified nursing assistants. If nurses are unable to "sell" this model to administration, it may be helpful to pilot the concept one one unit for a period of time and compare resident, family, and staff satisfaction with that of a similar unit. Also, it is critical to compare the financial implications, including cost per resident per day and rate of staff turnover, to weigh the model's effectiveness. This small sampling of five facilities indicates the average cost per resident per day is $10 less when using either the primary team or all licensed staff models than in facilities of comparable size. Hospitals have already passed the time when they have had to work smarter, leaner, and more efficiently. Can long-term care facilities afford not to do the same?  相似文献   
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针对胜利151海上作业浮吊船吊机的控制系统存在的问题,提出了可行的改造方案,并论述了全数字直流调速装置、PLC、PCC等新技术、新产品应用于该船吊机电力传动及控制系统改造中的技术实现方法。通过技术改造,使该船吊机的性能有了提高,可满足海洋石油工程的新要求。  相似文献   
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O6-benzylguanine (BG) is a potent, specific inactivator of the DNA repair protein O6-alkylguanine-DNA alkyltransferase (AGT), which enhances sensitivity to nitrosoureas in cells and tumor-bearing animals. BG is presently undergoing clinical trials for development as an agent to enhance the therapeutic index of alkylating agent chemotherapy. It has been reported that a polymorphism exists in the human agt gene, with about 15% of the Japanese population having arginine at codon 160 instead of glycine on the polypeptide (Y. Imai et al., Carcinogenesis, 16: 2441-2445, 1995). The resultant mutant AGT protein is equally effective against both methylated DNA as compared with wild type protein. However, this mutant AGT protein was less sensitive to inactivation by BG with a 20-fold increase in the ED50 value. This observation raised the possibility that a subpopulation of patients may be resistant to BG due to a single base change. We have demonstrated that this alteration also reduces the sensitivity to O6-benzyl-8-oxoguanine, an equally potent, yet much longer-lived human metabolite of BG. To test the possibility that this germ-line mutation of the agt gene might explain resistance to BG and O6-benzyl-8-oxoguanine of patients on our Phase I clinical trials, we evaluated the DNA from lymphocytes of 18 patients. The G160R mutation was not found in any of the 18 patients. To determine the frequency of this mutation in the United States population, DNA from 181 healthy individuals were investigated and, again, the mutation was not observed in this cohort. Therefore, if the mutation exists, it is in statistically <1.6% of the United States noncancerous population. To investigate the possibility that this mutation might be somatic, we evaluated genomic DNA samples from 94 human primary cancers of four different histological subtypes (brain, colon, esophageal, and head and neck). Again, none were found to have the G160R mutation.  相似文献   
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