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51.
Orwell Ralph L. Wood Ronald L. Tarran Jane Torpy Fraser Burchett Margaret D. 《Water, air, and soil pollution》2004,157(1-4):193-207
Water, Air, &; Soil Pollution - The quality of the indoor environment has become a major health consideration, since urban-dwellers spend 80-90% of their time indoors, where air pollution can be... 相似文献
52.
The C- and N-turnover of undisturbed, irrigated 25 cm soil microcosms of a Typic Agrudalf from loess were followed during a laboratory incubation of about 200 days. Besides the untreated control columns two treatments were installed to test the effects of the application of white mustard (Sinapis alba L.) on both nutrient cycles (either mixing the dried plant residues to 0–8 cm or surface application). Each of the treatments is represented by 4 soil columns to account for soil variability. The C-budget was mainly altered for soil respiration, which increased for the microcosms treated with mustard rapidly after application. After 4 weeks no differences could be proved however. The loss of soluble C-compounds, which was unimportant for the budget, reflected no one of the treatments with mustard. Net N mineralization, as calculated from the NO3-leaching, could be well fitted by zero-order kinetics. Although the high variability of the net N mineralization of the replicates mustard application significantly rises the N-release. No difference could be proved for the different techniques of application however. In the mixed treatment 38% of the nitrogen added with the mustard was decomposed during the incubation period, in the surface treatment 34%. 相似文献
53.
Bunzel M Ralph J Kim H Lu F Ralph SA Marita JM Hatfield RD Steinhart H 《Journal of agricultural and food chemistry》2003,51(5):1427-1434
Two 8-8-coupled sinapic acid dehydrodimers and at least three sinapate-ferulate heterodimers have been identified as saponification products from different insoluble and soluble cereal grain dietary fibers. The two 8-8-disinapates were authenticated by comparison of their GC retention times and mass spectra with authentic dehydrodimers synthesized from methyl or ethyl sinapate using two different single-electron metal oxidant systems. The highest amounts (481 microg/g) were found in wild rice insoluble dietary fiber. Model reactions showed that it is unlikely that the dehydrodisinapates detected are artifacts formed from free sinapic acid during the saponification procedure. The dehydrodisinapates presumably derive from radical coupling of sinapate-polymer esters in the cell wall; the radical coupling origin is further confirmed by finding 8-8 and 8-5 (and possibly 8-O-4) sinapate-ferulate cross-products. Sinapates therefore appear to have an analogous role to ferulates in cross-linking polysaccharides in cereal grains and presumably grass cell walls in general. 相似文献
54.
Dorfner R Ferge T Kettrup A Zimmermann R Yeretzian C 《Journal of agricultural and food chemistry》2003,51(19):5768-5773
The formation of 4-vinylguaiacol, guaiacol, and phenol during coffee roasting was monitored in real-time, using resonance enhanced multiphoton ionization and time-of-flight mass spectrometry. A model is proposed, based on two connected reaction channels. One channel, termed the "low activation energy" channel, consists of ester hydrolysis of 5-FQA followed by decarboxylation of the ferulic acid to form 4-vinylguaiacol, and finally polymerization at the vinyl group to form partly insoluble polymers (coffee melanoidins). The second "high activation energy" channel opens up once the beans have reached higher temperatures. It leads to formation of guaiacol, via oxidation of 4-vinylguaiacol, and subsequently to phenol and other phenolic VOCs. This work aims at developing strategies to modify the composition of coffee flavor compounds based on the time-temperature history during roasting. 相似文献
55.
The factors influencing the number of nightjars on 36 heathland sites (referred to as patches) in Dorset, England were examined using novel spatial integration of existing datasets. Surrogate measures of human density and settlement, including the amount of developed land at different distances from the heath (obtained from aerial photographs) and the actual number of buildings (obtained from Post Code databases) were all found to be highly correlated with each other and to show a strong negative relationship with the density of nightjars present on a patch, regardless of patch size. The amount of woodland (the preferred foraging habitat) surrounding each patch (within 500 m of the patch boundary) was also a significant predictor of nightjar numbers. When used together, the extent of woodland and developed land both gave significant improvements to predictions of nightjar density. The results indicate that the number of nightjars present on a heathland patch is influenced by the surrounding land-use and that the effect of urban development is more than just habitat loss. We suggest that trends identified are at least partly due to actual human presence on the heathlands and as such, human disturbance is potentially a problem for this species. 相似文献
56.
57.
Cisplatin Therapy in 41 Dogs With Malignant Tumors 总被引:3,自引:0,他引:3
Deborah W. Knapp DVM Ralph C. Richardson DVM Patty L. Bonney BS RVT Kevin Hahn DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(1):41-46
Forty-one dogs with a variety of histopathologically diagnosed, measurable tumors were treated with cisplatin (cis-diamminedichloroplatinum, Platinol, Bristol Laboratories, Syracuse, NY 13221-4755) as a single agent at a dosage of 60 mg/m2 given intravenously at 3-week intervals. In an attempt to avoid renal toxicity of cisplatin, saline diuresis was induced and maintained for 4 hours before and 2 hours following cisplatin administration. The dogs received one to ten doses of cisplatin. To determine response to therapy and to monitor toxicity of the drug, the dogs were evaluated with physical examinations including tumor measurements, radiography, complete blood counts, platelet counts, urinalyses, serum urea nitrogen concentrations, and serum creatinine concentrations. An overall response rate of 19% was observed. Complete remission occurred in one of 11 dogs with squamous cell carcinomas and one of one dog with a mediastinal undifferentiated carcinoma. Partial remissions were documented in one of 11 dogs with squamous cell carcinomas, two of three dogs with metastatic osteosarcomas, one of three dogs with nasal adenocarcinomas, and one of one dog with a thyroid adenocarcinoma. Toxic side effects were primarily gastrointestinal in nature, with vomiting occurring 1-6 hours after cisplatin administration in 27 of 41 dogs. Severe anorexia occurred in three dogs, and hemorrhagic diarrhea was observed in one dog. One dog developed grand mal seizures and died 3 hours following therapy. Granulocytopenia was documented in six dogs, and thrombocytopenia was observed in four dogs. One dog showed an increase in serum urea nitrogen and creatinine concentrations, but this patient had known pre-existing renal disease.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
Silviculturally-managed pine plantations within southern Ohio are chronically disturbed patches of introduced vegetation distinct from the surrounding matrix of hardwood forest. To determine the successional pathways by which such pine stands might blend back into the hardwood forest matrix under different types of silvicultural management, we determined the current status of hardwood regeneration under 24 pine stands. Stands of Pinus virginiana (Virginia pine) had the highest density of hardwood seedlings and saplings (20,560 stems ha-1) whereas P. strobus (white pine) stands averaged only 7090 hardwood stems ha-1; P. resinosa (red pine) stands were intermediate. The most abundant hardwood seedling and sapling species under pine canopies were Acer rubrum and Cornus florida. DCA ordination of the seedling + sapling assemblages clustered most of the P. resinosa and P. strobus stands in the center of the ordination along with a group of species which are common in second-growth forests of the area. P. virginiana stands, in contrast, were scattered throughout the ordination space. Most of the woody species common in second-growth forests of the region were also common in the pine understory. Multiple regression indicated that large plantations with deeper litter, higher soil pH and lower total hardwood density had the greatest abundance of mesic-site species in the understory. This relationship did not hold for P. resinosa stands, however, due to more frequent and intense silvicultural intervention. The seed bank was not an important source of woody seedlings to the understory assemblage under intact pine plantations. The vegetation of 1–4 yr old clear-cut sites was dominated by wind and bird dispersed species which were generally absent from the understory of intact plantations. We conclude these chronically disturbed planted patches will revert to matrix vegetation faster if the disturbance is allowed to end in a gradual manner through stand senescence than if it is abruptly ended by clear-cutting. 相似文献
59.
M Wendt 《Tier?rztliche Praxis》1987,15(4):375-376
Sudden death in mature sows due to torsion of abdominal organs (stomach, spleen, liver) is described. Hepatic torsion is seen only separately, but gastric torsion and torsion of spleen appear by themselves as well as in combination with each other. Often no clinical symptoms are observed. Acute cardiovascular failure is responsible for death in these sows. Authors unanimously report on feeding as a possible aetiological factor. Both the composition and technique of feeding should therefore be examined in problematic live stock. Excitement and excessive movements before and during feeding as well as the rapid intake of large amounts of water and feed seem to predispose to the development of gastric dilatation or torsion in sows. Suitable prophylactic measures should be taken. 相似文献
60.