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Etched track detectors are widely used for the detection of radon and its decay products. They have many desirable attributes: they are small, cheap, simple, non-toxic and non-hazardous. Etched track detectors provide adequate accuracy for most radiological protection purposes provided stringent quality assurance is maintained. The UK validation scheme provides an important component of QA but continuous monitoring of conditions and results is also needed. If these conditions are observed, these detectors provide an entirely adequate tool for large-scale use in assessing levels of radon in houses. Accurate estimates of long-term average radon levels require a measurement over several months because of the short-term fluctuations in radon concentrations.  相似文献   
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Leptospirosis is the most widespread zoonosis in the world. It is caused by pathogenic leptospira infection. This infection is also an uncommon cause of hepatorenal failure. Indeed, hemolysis, elevated liver enzyme levels and low platelet count syndrome, and acute fatty liver of pregnancy are specific to the pregnant state. Leptospirosis is rarely described in pregnancy; it might mimic puerperal sepsis or hepatorenal failure associated with pregnancy induced hypertension. We report a case of leptospirosis presenting as multiple organ failure during third trimester of pregnancy with a good outcome.  相似文献   
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Xu HX  Lu MD  Xie XY  Yin XY  Kuang M  Chen JW  Xu ZF  Liu GJ 《Clinical radiology》2005,60(9):1018-1025
AIM: To identify prognostic factors for long-term outcome for patients with hepatocellular carcinoma (HCC) after percutaneous microwave or radiofrequency ablation. MATERIALS AND METHODS: In total, 137 consecutive patients with HCC underwent microwave or radiofrequency ablation with curative intent; 16 possible prognostic factors were evaluated for their association with overall survival (OS) and disease-free survival (DFS) using univariate and multivariate analysis. RESULTS: The median OS and DFS were 27.0 months and 8.2 months, respectively. OS rates for all patients at 1, 2, 3, 4 and 5 years were 73.9%, 52.1%, 42.8%, 26.2% and 20.1%, respectively. DFS rates at 1, 2, 3 and 4 years were 38.1%, 21.9%, 18.8%, and 14.1%, respectively. Pretreatment serum alpha-fetoprotein (AFP) >200 ng/ml, pretreatment serum albumin 14 s were identified to be significant predictors for DFS by univariate analysis, and the former was the only independent predictor for DFS by multivariate analysis. CONCLUSION: Prognosis for patients with HCC after thermal ablation with curative intent was determined by treatment response to ablation, pretreatment serum AFP, and liver function reserve. Tumour response to treatment was the most predictive factor for long-term survival and was related to tumour size, thus careful selection of patients for ablation therapy is recommended.  相似文献   
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Human salivary anionic analysis using ion chromatography   总被引:1,自引:0,他引:1  
OBJECTIVE: To survey concentrations and time-variability of the major anions of human saliva using ion chromatography (IC). MATERIALS AND METHODS: Resting saliva samples after overnight fasting, obtained under standardized conditions in time-series for 10 subjects, were analysed for chloride, phosphate, nitrate, sulphate, thiocyanate, acetate and lactate. A second group of five subjects provided mixed saliva as before, and in addition a sample of parotid saliva collected immediately afterwards using a Lashley cup. Analysis was by ion chromatography (DX-100, Dionex) using 1.7 mM NaHCO3 + 1.8 mM Na2CO3 + 100 mg/L p-cyanophenol (2 mL/min) and 1.6 mM perfluorobutyric acid + 0.3 mM sodium hydroxide (0.3 mL/min) as eluents for inorganic and organic anions, respectively. RESULTS: The time-series data showed great natural variability. Analysis of the correlations showed that the concentration of nitrate was uncoupled from those of the other anions. Lactate was not detected. Parotid saliva showed marked differences from mixed saliva, most notably the absence of acetate and the presence in two instances of lactate. Bromide, nitrite and citrate were not detected. CONCLUSIONS: Acetate is a major component of the oral chemical environment. Simultaneous analyses permit the investigation of the relationships between component concentrations that otherwise might have been difficult to study.  相似文献   
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Six labdanes (1-6) and four isopimaranes (7-10), including three new natural products (7, 9, and 10), were isolated from Platycladus orientalis, and their structures determined using 1D and 2D NMR methods, ion-cyclotron resonance HRMS, and optical rotation data. Relative configurations of all chiral centers in the isopimaranes were determined using NOESY experiments at 600 and 800 MHz. Specific optical rotation data were used to correlate absolute configurations. Compounds 1-9 and aframodial (11) were tested for their in vitro antiplasmodial activity and for their ability to induce changes of erythrocyte shape in order to obtain data about possible correlation between the two effects. All compounds tested exhibited weak (IC(50) > 25 microM) in vitro antiplasmodial effects against Plasmodium falciparum strain 3D7. At the same time, the compounds caused echinocytic or stomatocytic changes of the erythrocyte membrane curvature, indicative of their incorporation into the lipid bilayer, in the concentration region where the antiplasmodial activity was observed. The antiplasmodial effect of these compounds thus appears to be an indirect effect on the erythrocyte host cell. Weak or moderate antiplasmodial activity observed with many other apolar natural products, in particular those with amphiphilic structures, is also likely to be an indirect effect.  相似文献   
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