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71.
Chefetz B 《Environmental toxicology and chemistry / SETAC》2003,22(10):2492-2498
Several studies have shown selective preservation of plant cuticular materials in soils. However, very little is known about their function as sorbents for the hydrophobic organic contaminants (HOCs) in the soil. In this study, we investigated the sorption and desorption of phenanthrene and atrazine by cuticular fractions of pepper (bulk, dewaxed, nonsaponifiable, and nonhydrolyzable) to better understand the sorptive activity of cuticular matter in soils. The bulk and dewaxed cuticles exhibited carbon-normalized distribution coefficients (Koc) for phenanthrene and atrazine in the range of that reported for soil humic substances, although both samples were rich in aliphatic structures. No hysteresis was observed in the desorption isotherms of either solute. The nonhydrolyzable residue exhibited a very high Koc value for atrazine, whereas the nonsaponifiable sample be exhibited the lowest Koc value for both sorbates. Based on solubility parameter data, it is suggested that the nonsponifiable sample be considered an intermediate between the physical and chemical mixture of pectin and cutan/lignin-like fractions, whereas the dewaxed cuticle is a chemical blending of cutin and pectin. The n-hexane-normalized sorption data suggest that the pepper cuticle can interact specifically with atrazine. This study leads to the conclusion that the contribution of aliphatic-rich plant biopolymers to the sorption of HOCs can be significant because of their preservation and accumulation in soils. 相似文献
72.
Perri F Zagari RM Uebersax JS Quitadamo M Bazzoli F;Helicobacter Pylori Sige Study Group on ¹³CO₂ Measurement Standardization Amarri S Armuzzi A Cantoni F Colombo R De Berardinis F De Pretis G Dell'Anna L Festi D Neri M Geypens B Ierardi E Johnson P Marchi S Masoero G Micunco C Palli D Russo A Palmas F Realdi G Sangaletti O Savarino V Stellaard F Vigneri S 《Alimentary pharmacology & therapeutics》2003,17(10):1291-1297
BACKGROUND: 13C breath test analysis requires accurate 13CO2 measurements. AIM:: To perform a multicentre study to evaluate the repeatability and reproducibility of breath 13CO2 analysis. METHODS: Two series of 25 paired randomly coded tubes (each consisting of 23 13CO2-enriched breath samples and two samples of standard reference pure CO2 with certified delta 13CPDB) were sent to participating centres for 13CO2 measurement. Each series of tubes was analysed 10 days apart. The repeatability and reproducibility of 13C measurements was assessed by Mandel's k and h statistics. RESULTS: Twenty-two centres participated in the study: 18 showed good inter- and intra-laboratory variability, whilst four showed abnormally high inter- or intra-laboratory variability. Breath test results were also significantly affected by the accuracy of the 13C analytical procedures. CONCLUSIONS: A low accuracy of 13C measurements may significantly affect the results of breath tests, leading to inappropriate clinical decisions. Standardization of 13C analysis is required to guarantee optimal 13C measurements and accurate 13C breath test results. 相似文献
73.
1. The present study found that, compared with mouse heart and liver, P388 ascitic tumour had significantly lower superoxide dismutase (SOD) activity and that compared with the mouse liver, the heart had significantly lower SOD and catalase activities, as well as a lower glutathione content. 2. At 7.5 mg/kg, doxorubicin (DOX), a superoxide radical inducer, induced significant lipid peroxidation only in the tumour, whereas 15.0 mg/kg DOX induced lipid peroxidation in both the tumour and heart, but not in the liver. 3. Overall, the results of the present study suggest that the differential anti-oxidant activities in P388 ascitic tumour, heart and liver in mice may explain their differential responses and, hence, susceptibility to DOX-induced lipid peroxidation. 相似文献
74.
A traditional esterolytic assay, a commercial chromogenic assay and an in-house chromogenic assay were compared for suitability in estimating C 1 esterase inhibitor (C 1 INH) activity in plasma and fractions obtained during preparation of a clinical concentrate of C 1 INH. The esterolytic and both of the chromogenic assays showed similar C 1 INH activity in unfractionated plasma samples. However, the esterolytic assay was significantly influenced by the buffer pH and concentration in fractionated plasma samples, and this often resulted in a significant overestimation of C 1 INH in some fractions. Similarly, the commercial C 1 INH assay kit did not always reliably estimate C 1 INH activity in fractions derived from plasma. A modified in-house functional assay was found to be more reliable in measuring C 1 INH in fractionated plasma samples. There was a good correlation between this activity assay and immunological assay estimates of C 1 INH in fractions derived from plasma. 相似文献
75.
76.
77.
Exchange transfusion as an adjunct to the treatment of severe falciparum malaria: case report and review 总被引:1,自引:0,他引:1
Malaria associated with complications or a fatal outcome is almost always caused by Plasmodium falciparum. The mortality due to this disease parallels the degree of parasitemia. Successful use of exchange blood transfusion as a therapeutic adjunct for this infection was first reported in 1974, although the efficacy of this procedure has not been established by randomized, controlled trials. The rationale for this form of therapy is based on: (1) rapid reduction in the parasite load by direct removal; (2) decreased risk of severe intravascular hemolysis and its consequences (disseminated intravascular coagulation and renal dysfunction); (3) improved rheology with transfused blood and reduced microcirculatory sludging; and (4) improved oxygen-carrying capacity with transfused erythrocytes. We describe a case of severe falciparum malaria and review the literature describing the use of exchange transfusion for treatment of this infection. 相似文献
78.
Alexander Albrecht Benny Levenson Klaus -Dirk Henke J. -Matthias Graf von Schulenburg Alexander Albrecht Peter Bossiljanoff Benny Levenson Rolf Mertens Matthias Redecker Rainer Schräder Hans F. Spieß Kay Thierfelder Bernhard Bohlen Gerd Kleiber Michael Lehnert Gäste Wolfgang Stark Josef Fahn Helmut Heckenstaller Ernst Thiel 《Herz》1999,24(1):89-91
Ohne Zusammenfassung 相似文献
79.
Objective To determine the effect of different mattresses on cardiopulmonary resuscitation performance and establish whether emergency deflation of an inflatable mattress improves the quality of resuscitation.Design and setting Randomised controlled cross-over trial performed in a general ICUParticipants Critical care staff from a general ICU.Interventions Cardiopulmonary resuscitation on a manikin on the floor or on a bed with a standard foam mattress and inflated and deflated pressure redistributing mattresses. Maximal compression force was measured at different bed heights.Measurements and results Compression depth, duty cycle and rate and percentage correct expired air ventilation were recorded on a manikin. Compression depth was significantly lower on the foam (35.2 mm), inflated (37.2 mm) and deflated mattress (39.1 mm) than the floor (44.2 mm). There were no clinically important differences in duty cycle or compression rate. The quality of ventilation was poor on all surfaces. Maximal compression force declined as bed height increased.Conclusions Resuscitation performance is adversely affected when performed on a bed (irrespective of mattress type) compared to the floor. There were no differences between the inflated and deflated mattresses, although the deflation process did not adversely affect performance. This study does not support the routine deflation of an inflated mattress during resuscitation and questions the potential benefits from using a backboard. The finding that bed height affects maximal compression forces, challenges the recommendation that cardiopulmonary resuscitation be performed with the bed at middle-thigh level and requires further investigation.Dr. Robert Benny was tragically killed in a road accident during the Summer of 2003. Dr. Benny was at the very start of a promising career in surgery. Our thoughts go to his family and friends.G.D.P. and M.T. have received travelling fellowships from Huntleigh Healthcare, and M.T. has previously delivered lectures for Huntleigh Healthcare. 相似文献
80.
Sigurd?H.?BervenEmail author Steven?J.?Kamper Niccole?M.?Germscheid Benny?Dahl Christopher?I.?Shaffrey Lawrence?G.?Lenke Stephen?J.?Lewis Kenneth?M.?Cheung Ahmet?Alanay Manabu?Ito David?W.?Polly Yong?Qiu Marinus?de?Kleuver AOSpine Knowledge Forum Deformity 《European spine journal》2018,27(3):585-596