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1.
E J de Vries J Zeeman R J Esser B Borsje F J Mulder 《Journal of the Association of Official Analytical Chemists》1979,62(6):1285-1291
Vitamin D is determined in preparations containing other fat-soluble vitamins by high performance liquid chromatography (HPLC). The unsaponifiable residue is extracted and separated from interferences by reverse phase chromatography; the fraction corresponding to vitamin D3 is collected and quantitated using normal phase chromatography (amylalcohol-n-hexane as mobile phase) by measuring the vitamin D3 and pre-vitamin D3 peaks at 254 nm. Previtamin D3 content is calculated as vitamin D3 with a conversion factor (determined on the equipment used). Application of the method to vitamin AD3 mixtures in oils gives 98-102% recovery. The reproducibility, using an external standard, is 2-3%, calculated as the coefficient of variation; with an internal standard, the coefficient of variation is 1-1.5%. The method measures potential vitamin D3 content in preparations containing greater than or equal to 200 IU/g in the presence of all known vitamin D3 isomers, vitamin A, and vitamin E. 相似文献
2.
Inductively coupled plasma mass‐spectrometric determination of platinum in excretion products of client‐owned pet dogs 下载免费PDF全文
T. Janssens E. E. M. Brouwers J. P. de Vos N. de Vries J. H. M. Schellens J. H. Beijnen 《Veterinary and comparative oncology》2015,13(2):124-132
Residues of antineoplastic drugs in canine excretion products may represent exposure risks to veterinary personnel, owners of pet dogs and other animal care‐takers. The aim of this study was to measure the extent and duration of platinum (Pt) excretion in pet dogs treated with carboplatin. Samples were collected before and up to 21 days after administration of carboplatin. We used validated, ultra‐sensitive, inductively coupled plasma‐mass spectrometry assays to measure Pt in canine urine, faeces, saliva, sebum and cerumen. Results showed that urine is the major route of elimination of Pt in dogs. In addition, excretion occurs via faeces and saliva, with the highest amounts eliminated during the first 5 days. The amount of excreted Pt decreased over time but was still quantifiable at 21 days after administration of carboplatin. In conclusion, increased Pt levels were found in all measured excretion products up to 21 days after administration of carboplatin to pet dogs, with urine as the main route of excretion. These findings may be used to further adapt current veterinary guidelines on safe handling of antineoplastic drugs and treated animals. 相似文献
3.
4.
Van den Hout K. D. Bakker D. J. Berdowski J. J. M. Van Jaarsveld J. A. Reinds G. J. Bril J. Breeuwsma A. Groenenberg J. E. De Vries W. Van Pagee J. A. Villars M. Sliggers C. J. 《Water, air, and soil pollution》1999,109(1-4):357-396
In the pilot study ESQUAD the impact of atmospheric deposition of three heavy metals (cadmium, copper and lead) and two persistent organic pollutants (benzo(a)-pyrene and lindane) on the quality of European soils and seawater has been calculated. Calculations have been made of atmospheric transport and deposition using a detailed emissions database for Europe. This enabled deposition maps to be produced to a resolution of approximately 50 km. The distribution of pollutant concentrations in forest soils was calculated for each grid cell using a database of soil property parameters in Europe. For the North Sea, a model was used to map long-term concentrations in water and sediment, which are due to atmospheric deposition and other, non-atmospheric sources. The model calculations allowed detailed comparisons of deposition fluxes and concentrations of the substances studied with critical loads and environmental quality threshold values, including critical loads. Although significant uncertainties were identified, the study gives insight in how threshold exceedance rates in Europe relate to pollutant type, threshold type, environmental compartment and chemophysical phase (adsorbed, dissolved). For all pollutants and for all compartments exceedances were calculated for at least some of the quality thresholds that were chosen. 相似文献
5.
Chest wall reconstruction with latissimus dorsi and an autologous thoracolumbar fascia graft in a dog 下载免费PDF全文
A. de Battisti G. Polton M. de Vries E. Friend 《The Journal of small animal practice》2015,56(3):218-222
A new technique for autogenous chest wall reconstruction using a latissimus dorsi muscle flap and a free graft of thoracolumbar fascia was utilised in a two‐year‐old Dobermann after resection of a high‐grade osteosarcoma from the left thoracic wall. En bloc excision of the chest wall mass, including six ribs, was performed. The resulting chest wall defect was too large to be reconstructed with only a pedicled muscle flap and was reconstructed with a latissimus dorsi muscle flap cranially and a free graft of thoracolumbar fascia caudally. The graft was harvested easily, and there was no donor site morbidity or postoperative complications. A free graft of thoracolumbar fascia can be considered as an option to supplement autogenous reconstruction of the chest wall. 相似文献
6.
J. H. M. Hovenkamp-Hermelink E. Jacobsen L. P. Pijnacker J. N. de Vries B. Witholt W. J. Feenstra 《Euphytica》1988,39(3):213-219
Summary A three step procedure for adventitious shoot regeneration on leaf explants of monoploid potato clone H7322 and a minituber induction procedure on stem segments have been described. Chromosome counts on 92 adventitious shoots showed that 85% of them had been polyploidized, i.e., 71% were diploid, 1% tetraploid, and 13% were mixoploid. Cytophotometric studies on nuclei of soil grown tubers of tetraploid cv Astarte, of 1x, 2x and 4x adventitious shoots of H7322, and of diploid H2578 showed in all cases polyploidization with prominent classes up to 8C and 16C. However, nuclei of pith cells of 5 weeks old minitubers which had developed on monoploid H7322 itself or on 1x adventitious shoots of H7322 showed predominantly 1C and 2C values. Pith cells of minitubers of monoploid H7322 were screened, after iodine staining, for the presence of variant cells containing reddish-brown staining (amylose-free) starch. In more than 75% of the investigated minitubers one or a few of such variant cells were found indicating that such a variation occurs in minitubers of monoploid potato and that this variant character is expressed in cells of vegetative storage organs like potato tubers. 相似文献
7.
D. P. De Vries 《Euphytica》1965,14(1):78-82
In 9–13 year old cherry seedling populations, totalling 1,033 individuals, a preliminary selection was made in 1963, for field resistance to bacterial canker (Pseudomonas syringae
van Hall).The field resistance of the three cherry species used, P. avium, P. cerasus and P. avium × P. cerasus, has shown to be low, high and very high, respectively. 相似文献
8.
Summary Thirty, one-season-old Rosa canina Inermis seedlings (8–12 mm in diameter) were grown in the greenhouse. After 5 months, single-node softwood cuttings were made of each plant. Analysis of variance demonstrated marked differences between the internode length, number of leaflets per leaf and the leaf area of the original seedling, and between the time of axillary bud-break, axillary sprout length and weight of adventitious roots of their 23-day-old cuttings. Clonal root weight of cuttings was highly significantly correlated with: number of leaflets per leaf (r=–0.65), leaf area (r=+0.65), and days to axillary bud-break (r=+0.62). The origin of heterogeneity among Inermis seedling rootstocks, its probable effect on the flower production of cut roses and its possible use in the selection for clonal rootstocks are discussed. 相似文献
9.
H H Chang J W De Vries W E Hobbs 《Journal of the Association of Official Analytical Chemists》1979,62(6):1281-1284
The difference between the CB and Best Foods methods in extracting aflatoxins from peanut products has been studied. The CB method yields 60, 121, 35, and 22% higher results for aflatoxins B1, B2, G1, and G2, respectively for 4 samples of peanut meal and 6 samples of peanut butter studied. Both reverse phase liquid chromatography and thin layer chromatography were used to quantitate the extracted aflatoxins. 相似文献
10.