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81.
Holm  P.E.  Christensen  T.H.  Lorenz  S.E.  Hamon  R.E.  Domingues  H.C.  Sequeira  E.M.  McGrath  S.P. 《Water, air, and soil pollution》1998,102(1-2):105-115
Soil water concentrations of cadmium and zinc were measured in plant pots with 15 contaminated soils which differed in origin, texture, pH (5.1 – 7.8) and concentrations of cadmium (0.2 – 17 mg Cd kg-1) and zinc (36 – 1300 mg Zn kg-1). The soil waters contained total concentrations of 0.5 to 17 µg Cd L-1 and 9 to 3600 µg Zn L-1, which were dominated by free metal ions as measured by an ion exchange-resin method. Annual leaching outflows were estimated from soil water concentrations to be 0.5 – 17 g Cd ha-1 y-1 and 9 – 3600 g Zn ha-1 y-1 per 100 mm of net percolation, corresponding to 0.1% per year of the total soil content of cadmium and zinc. The measured soil water concentrations of cadmium and zinc did not correlate linearly with the corresponding soil concentrations but correlated fairly well with concentrations measured in Ca(NO3)2 extracts of the soils and with soil water concentrations estimated from soil concentrations and pH. Such concentration estimates may be useful for estimating amounts of cadmium and zinc being leached from soils.  相似文献   
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Malignant lymphoma involving bone and heart was diagnosed in a 4-year-old Whippet, using radiography, histologic examination, nuclear scintigraphy of the skeleton and heart, and cardiac ultrasonography.  相似文献   
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Sucralose is a chlorinated carbohydrate nonnutritive sweetener of food and beverage products. The determination of sucralose in food and beverages is important to ensure consistency in product quality. Sucralose was determined in two commercial products without sample preparation using high-performance anion-exchange (HPAE) chromatography coupled with pulsed amperometric detection (PAD). Sucralose was determined with a 10 min isocratic separation. To determine sucralose and other carbohydrates (e.g., dextrose) simultaneously, a gradient separation was developed. The linear range of electrochemical response extended over 3 orders of magnitude, from 0.01 (LOD) to 40 microM (16 microg/mL; 25 microL injection). High precision, high spike recovery, and method ruggedness were observed for both samples.  相似文献   
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The quantification of slow-growing mycobacteria such as Mycobacterium tuberculosis or M. bovis from in vitro and in vivo samples is complicated by their long generation time, their ability to form aggregates, and their capacity to persist in a state of dormancy. We compared different methods for the establishment of growth curves for broth cultures of M. bovis bacille Calmette-Guérin (BCG). A quantitative TaqMan-PCR yielded results comparable with those obtained by protein quantification and measurement of the ATP content of the cultures. The quantitative TaqMan-PCR furthermore turned out to be particularly suitable for the measurement of multiplication of BCG within eukaryotic cells. Furthermore, it is a fast method allowing an estimation of the mycobacterial load in tissue long before colony counts can be obtained.  相似文献   
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Effects of a 20-h fermentation on cell wall polysaccharides from the mucilage of pulped coffee beans were examined and compared to those of unfermented beans, on alcohol insoluble residues (AIRs), their hot-water-soluble crude pectic substances (PECTs), and their hot-water-insoluble residues (RESs). Yields and compositions were very similar: AIRs, which consisted of approximately 30% highly methylated pectic substances, approximately 9% cellulose, and approximately 15% neutral noncellulosic polysaccharides, exhibited no apparent degradation. However, PECTs from fermented beans were shown to have undergone a slight reduction of their intrinsic viscosity and weight-average molecular weight by capillary viscosimetry and high-performance size-exclusion chromatography. After fermentation, hot-water-insoluble pectic substances of RES exhibited partial de-esterification. Removal of coffee bean mucilage by natural fermentation seems to result from a restricted pectolysis, the mechanism of which remains to be elucidated.  相似文献   
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The sciatic nerve was surgically transected in 6 dogs. The resulting dysfunction and the positive effects of a transfer of the tendon of the vastus lateralis muscle to the long digital extensor muscle were evaluated, alone and in combination with a talocrural arthrodesis. Two dogs that received both arthrodesis and tendon transfer showed the greatest improvement in gait.  相似文献   
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