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91.
Parikka K Rowland IR Welch RW Wähälä K 《Journal of agricultural and food chemistry》2006,54(5):1646-1650
Incubation with 5-n-alkylresorcinols (chain lengths C15:0, C17:0, C19:0, C21:0, and C23:0) increased the self-protection capacity of HT29 human colon cancer cells against DNA damage induced by hydrogen peroxide and genotoxic fecal water samples using comet assay (single-cell gel electrophoresis assay). The alkylresorcinols did not exert potent antioxidant activity in the FRAP (ferric reduction ability of plasma) and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical assays. However they were able to significantly inhibit copper-mediated oxidation of human LDL (low-density lipoprotein) in vitro, and pentadecylresorcinol at 25 micromol/L increased lag time by 65 min. The results show that alkylresorcinols have antigenotoxic and antioxidant activity under in vitro conditions. 相似文献
92.
The effects of a neonatal calf diarrhea virus on cell cultures were investigated. Bovine embryonic kidney cell cultures were the most satisfactory for production of virus. Cytoplasmic changes detected after inoculation with a high multiplicity of virus were: 1) cytoplasmic vacuoles; 2) some eosinophilic cytoplasmic inclusions; and 3) some degeneration of cells and detachment from the monolayer. Cultures stained with fluorescein-labeled antibody showed cytoplasmic fluorescence as early as four hr after infection with the maximum fluorescence at five days. No cross reactions were observed between the neonatal calf diarrhea virus and reovirus type 1 or type 3 by the fluorescent antibody technique. Plaques were small and were not produced consistently. The optimal adsorption time was one to two hr. The maximum titer was reached at 18 hr, with the cell-associated titer remaining higher than the cell-free titer until that time. An interferon was produced by cultures infected with either ultraviolet-inactivated or untreated virus. 相似文献
93.
94.
Effect of beet pulp and citrus pulp on rumination activity 总被引:1,自引:0,他引:1
95.
Twenty-six composite samples of fish were collected during 1978 from United States watersheds near the Great Lakes and analyzed for polychlorinated biphenyls (PCBs) and related organic chemicals. PCB mixtures resembling Aroclor 1254 were found in all samples, and mixtures resembling Aroclor 1242 (or 1016) were found in 77 percent of the samples. Total PCB concentrations in the whole-fish composite samples ranged from 0.13 to 14.6 ppm; 65 percent of the samples contained more than 2 ppm PCBs. DDT and its metabolites were found in all samples. sigma DDT concentration was 1.66 ppm, and 81 percent of the samples contained less than 1.0 ppm sigma DDT. Chlordane ranged from less than 0.001 to 2.57 ppm in 38 percent of the samples. Hexachlorobenzene was found in 65 percent of the samples, ranging from less than 0.005 to 0.447 ppm. Other chemicals identified by gas chromatography/mass spectrometry included petroleum hydrocarbons and chlorobenzenes, chlorostyrenes, chlorophenols, and chlorinated aliphatic compounds. Fish from the Ashtabula River (Ohio), Rock River (Ohio), and Wabash River (Indiana) contained extremely complex residues of chlorinated and other organic chemicals. 相似文献
96.
M K Chaffin I C Fuenteabla J Schumacher R D Welch J F Edwards 《Equine veterinary journal》1992,24(5):372-378
The medical records of 11 horses with idiopathic muscular hypertrophy (MH) of the small intestine were reviewed to determine the clinical and pathological features of the disease. The median age of affected horses was 10.0 years (range 5-18 years). No breed or sex predisposition was apparent. Ten horses (91%) had chronic (23 days to 2.4 years) signs of mild, intermittent colic, and 1 horse had signs of severe colic of only 3 days' duration. Partial anorexia and chronic weight loss of variable duration (1-6 months) were prominent historical findings in 5 (45%) horses. Diagnostic tests, with the exception of exploratory caeliotomy, were ineffective for definitive diagnosis of intestinal MH as a cause of colic. In 2 horses, however, a thickened, rigid ileum was detected by palpation per rectum, and in 5 horses, multiple loops of distended small intestine were detected by palpation per rectum. Hypertrophy of both the circular and longitudinal layers of muscularis was determined as the cause of intestinal thickening in all horses. Muscular hypertrophy of the ileum was present in 9 (82%) horses. Two horses (18%) had MH of a section of jejunum only, and 4 (36%) horses had MH of the ileum in combination with MH of other sections of small intestine. Two (18%) horses had MH of the entire small intestine. In 9 (82%) horses, intestinal MH resulted in narrowing of the luminal diameter at the site of MH. Small diverticula were present on the mesenteric border of the hypertrophied ileum of 5 (45%) horses. Five linear (up to 150-cm) diverticula were present in the hypertrophied jejunum of 1 (9%) horse. Haemomelasma ilei was present on the antimesenteric serosal surface of affected intestine of 8 (73%) horses. Full-thickness rupture of the ileum with subsequent diffuse, septic peritonitis occurred in 3 (27%) horses. 相似文献
97.
A GIS database developed for Lake Marion, South Carolina was utilized to assess existing relationships between aquatic macrophyte distributions and environmental parameters affecting plant growth. The significance of water depth, sedimentation, nitrogen, phosphorus, top dissolved oxygen, bottom dissolved oxygen, percent light and absolute light was tested using GIS overlay techniques and the Chi Square test of independence. Specific levels of the eight parameters found to be spatially related to aquatic vegetation were then utilized to develop a provisional cartographic model describing optimum growth conditions for aquatic macrophytes. Model validation by comparing predicted vegetation with actual vegetation distributions indicated only water depth and sedimentation data layers are necessary for predicting more than 90 percent of emergent and submergent distributions. Resource managers can use this model to identify lake areas that are susceptible to excessive macrophyte growth and require special attention. 相似文献
98.
Sharon L Welch 《Veterinary Clinics of North America: Small Animal Practice》2002,32(2):443-53, vii
This chapter covers the hazards that some topical pharmaceutical preparations pose to animals who consume them. Included are medications containing calcipotriene, vitamins A and D, zinc oxide, 5-fluorouracil, brimonidine, imidazoline decongestants, local anesthetics, corticosteroids, antibiotics, salicylates, and benzoyl peroxide. 相似文献
99.
The name of the senior author of "Catecholamine uptake in cerebral cortex: an adaptive change induced by fighting" (8 June 1973, page 1050) was misspelled. It should be Edith D. Hendley and not Edith D. Henley. 相似文献
100.