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81.
Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals.  相似文献   
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The hazard of serious intoxication of agricultural field workers by organophosphate insecticide residues has led to the establishment of reentry intervals in California. In the attempt to extend this concept nationally, it has been found that there is a lack of relevant field data for setting of such standards. In an effort to expand knowledge of the relationship between foliar residue levels and occupational hazard, an examination of the persistence and transport of ethion, Zolone, and their oxygen analogs on grape foliage was conducted. Both dislodgeable and penetrated residues were followed for 28 days post-application for both insecticides while soil surface residues were followed for ethion only.A marked difference is seen in the decay rates of the dislodgeable vs. the penetrated residues of ethion, the dislodgeable residues decaying more quickly. This difference is not apparent for Zolone. Of particular significance to worker hazard is the finding that the oxones of both ethion and Zolone in the dislodgeable residues reach a plateau after approximately seven days and do not degrade further by day 28.  相似文献   
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There is a wide range in the expression of major histocompatability complex (MHC) class II HLA-DR molecules on freshly isolated human peripheral blood monocytes from one individual. This study determined whether the variability in HLA-DR expression on monocytes correlated with their oxidative burst capability after treatment with either phorbol myristate acetate (PMA) or calcium ionophore A23187. Freshly obtained cells were incubated with 2',7'-dichlorofluorescin diacetate (DCFH-DA), a dye which is utilized for the determination of cell oxidative potential by flow cytometry. Cells were stimulated, and then stained with phycoerythrin (PE)-labeled monoclonal antibodies (mAb). Two-color flow cytometry was used to determine changes in DCFH-DA (green) fluorescence which corresponded to oxidative product formation by cells which stained only with the PE-labeled mAb (monocytes). While monocytes with a high or low surface density of HLA-DR differed substantially in HLA-DR expression, only small differences in oxidative capability between "high" and "low" subsets were observed. Thus, monocytes which are very different in HLA-DR expression possess very similar oxidative burst capabilities.  相似文献   
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Hexanitrohexaazaisowurtzitane, or CL-20, is an emerging highly energetic compound currently under consideration for military applications. With the anticipated wide use of CL-20, there is the potential for soil and groundwater contamination resulting in adverse toxicologic effects on environmental receptors. Presently, there is a lack of data describing the toxic effects of CL-20 on avian species. The present study describes the effect of CL-20 on Japanese quail (Coturnix coturnix japonica) modified from standard toxicity test guidelines. First, a 14-day subacute assay was adopted using repeated gavage doses (0, 307, 964, 2439, 3475, or 5304 mg CL-20/kg body weight (BW)/d for 5 days followed by no CL-20 exposure (vehicle only) for 10 days. Second, a subchronic feeding assay (0, 11, 114, or 1085 mg CL-20/kg feed) was done for 42 days. During both studies, no overt toxicity was observed in the CL-20–treated birds. During the first 5 days of the subacute study, CL-20–exposed birds showed a dose-dependent decrease in BW gain, whereas increased liver weight, plasma sodium, and creatinine levels were observed in birds receiving the highest dose tested. For the subchronic study, embryo weights were significantly decreased in a dose-dependent manner. Embryos from CL-20–exposed birds were observed to have multiple cranial and facial deformities, beak curvatures, possible mid-brain enlargement, and classic one-sided development with micro-opthalamia (nonstatistical comparisons with control embryos). A trend toward decreased number of eggs laid per female bird was also observed. We conclude that CL-20 (or its degradation products) elicits few effects in adults but may affect avian development, although these preliminary findings should be confirmed.  相似文献   
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In this study, the effect of dietary vitamin E on the hepatic tumor-promoting activity of PCB-77 and PCB-153 in female Sprague-Dawley rats (175-200 g) was investigated. One week after diethylnitrosamine injection, rats were fed purified diets containing 10, 50, or 250 mg/kg vitamin E in the form of alpha-tocopheryl acetate. Starting 1 wk later, we injected rats i.p. with vehicle (corn oil) or PCB-77 or PCB-153 (300 mumol/kg) every 14 d for 4 injections. All rats were killed 10 d after the last PCB injection. The number and volume of placental glutathione S-transferase (PGST)-positive foci were increased by PCB-77 but not by PCB-153. Vitamin E did not affect the induction of PGST-positive foci. PCB-77, but not PCB-153, increased hepatic NF-kappaB activity. In conclusion, dietary vitamin E supplementation does not protect against the induction of altered hepatic focal lesions by PCBs.  相似文献   
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BACKGROUND: The purpose of this study is to examine the effect of various risk factors on complications in patients undergoing pedicled transverse rectus abdominis musculocutaneous (TRAM) flap breast reconstruction. METHODS: A retrospective review of 224 pedicled TRAMs in 200 patients over a 10-year period was carried out. Patients were divided into subgroups based on smoking history, weight, radiation status, and pedicle type. Complication rates were calculated and logistic regression analysis was used to identify risk factors. RESULTS: Logistic regression identified active smoking as a statistically significant risk factor for developing multiple (2 or more) flap complications (P = 0.0061) and TRAM infection (P = 0.0255), while former smoking was a risk factor for multiple flap complications (P = 0.01) and TRAM-delayed wound healing (P = 0.0433). Obesity (body mass index > or =30) was found to be a statistically significant risk factor for overall (1 or more) donor-site complications (P = 0.0281), overall flap complications (P = 0.0375), multiple flap complications (P = 0.0002), TRAM-delayed wound healing (P = 0.0334), and minor flap necrosis (P = 0.0075). CONCLUSIONS: This study identified that active or former smoking and obesity contribute to a significant complication rate, while overweight body habitus, use of double-pedicled flaps, and pre-TRAM radiation do not. This second decade "look-back" on pedicled TRAM flap breast reconstruction emphasizes the need for appropriate patient selection to achieve successful results with pedicled TRAM breast reconstruction.  相似文献   
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