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排序方式: 共有317条查询结果,搜索用时 31 毫秒
141.
142.
Erika G. Loftin DVM Lee V. Herold DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2009,19(5):501-506
Objective – To report a suspected toxicity in 2 dogs; to discuss therapy and prognosis.
Series Summary – Suspected alpha lipoic acid (ALA) toxicity was diagnosed based on clinical history and compatible laboratory findings in 2 dogs. Case 1 was presented within 10 hours of ALA ingestion, with initial behavioral changes likely due to hypoglycemia. During the course of hospitalization, hypoglycemia persisted and evidence of acute hepatic insult developed. With aggressive supportive care (including IV fluids with dextrose supplementation, hepatoprotective medications, and a plasma transfusion), he made a full recovery. Case 2 was presented approximately 60 hours after ALA ingestion, and was found to be in oliguric renal failure. She was treated with IV fluids, gastroprotective medications, and furosemide, but her condition deteriorated and she was ultimately euthanized within 16 hours of admission to the hospital.
New or Unique Information Provided – ALA is an uncommon but serious toxin that should be considered in cases presenting with hypoglycemia, acute renal failure, or acute hepatic insult. 相似文献
Series Summary – Suspected alpha lipoic acid (ALA) toxicity was diagnosed based on clinical history and compatible laboratory findings in 2 dogs. Case 1 was presented within 10 hours of ALA ingestion, with initial behavioral changes likely due to hypoglycemia. During the course of hospitalization, hypoglycemia persisted and evidence of acute hepatic insult developed. With aggressive supportive care (including IV fluids with dextrose supplementation, hepatoprotective medications, and a plasma transfusion), he made a full recovery. Case 2 was presented approximately 60 hours after ALA ingestion, and was found to be in oliguric renal failure. She was treated with IV fluids, gastroprotective medications, and furosemide, but her condition deteriorated and she was ultimately euthanized within 16 hours of admission to the hospital.
New or Unique Information Provided – ALA is an uncommon but serious toxin that should be considered in cases presenting with hypoglycemia, acute renal failure, or acute hepatic insult. 相似文献
143.
Pfeiffer E Hildebrand AA Becker C Schnattinger C Baumann S Rapp A Goesmann H Syldatk C Metzler M 《Journal of agricultural and food chemistry》2010,58(22):12055-12062
The mycotoxin zearalenone (ZEN) is produced by various Fusarium fungi and frequently found as a contaminant in food and feed. There are reports in the literature that several closely related analogues of ZEN are also formed in cultures of Fusarium species. We have therefore analyzed the organic extract from a 40 day culture of Fusarium graminearum by LC-DAD-MS and detected 15 compounds, which could be congeners of ZEN because of their ultraviolet, mass spectroscopy, and tandem mass spectroscopy spectra. In addition to confirming the previously reported α- and β-stereoisomers of 5-hydroxy-ZEN and 10-hydroxy-ZEN, we identified seven ZEN congeners for the first time. One of the major novel congeners was shown by nuclear magnetic resonance spectroscopy and chemical synthesis to have the structure of an aliphatic ZEN epoxide, whereas two minor products proved to be the corresponding dihydrodiols. In addition, three stereoisomers of a cyclization product of the dihydrodiols, carrying a spiro-acetal group, were identified as fungal products for the first time. The latter may be artifacts, because the ZEN epoxide and dihydrodiol are unstable under acidic conditions and rearrange easily to the spiro-acetal compounds. 相似文献
144.
145.
Kirschbaum-Titze P Mueller-Seitz E Petz M 《Journal of agricultural and food chemistry》2002,50(5):1264-1266
The capsaicinoid content of individual fruits from a single plant harvested at the same time after flowering exhibits a wide range of values with a rather uniform pattern for the ratio of capsaicin, dihydrocapsaicin, and nordihydrocapsaicin. This observation is confirmed by the analysis of fruits from a second and third plant and for several harvest times at different stages of maturity. Competition with lignin-like material, environmental influences, and subcellular distribution may play a role in the synthesis and transformation of capsaicinoids. 相似文献
146.
Valladares GR Zapata A Zygadlo J Banchio E 《Journal of agricultural and food chemistry》2002,50(14):4059-4061
Plant tissues may show chemical changes following herbivory. In aromatic plants such changes could affect the specific compounds on which commercial exploitation is based. This possibility was analyzed for Mintosthachys mollis, a member of the Lamiaceae native to Central Argentina with medicinal and aromatic uses in the region, and two types of insect herbivores: a leaf miner and a gall insect. Analysis of the essential oils of mined/undamaged leaves, as well as leaves from stems with and without galls, revealed changes in concentrations of the two main monoterpenes. A decrease in pulegone concentration was associated with both types of insect damage, whereas menthone increased significantly only in mined leaves. Inducible chemical changes in aromatic and medicinal plants may be common and widespread; their economic implications deserve investigation. 相似文献
147.
Anita Gl Tony J. Vyn Erika Michli Eileen J. Kladivko William W. McFee 《Soil & Tillage Research》2007,96(1-2):42-51
Numerous investigators of tillage system impacts on soil organic carbon (OC) or total nitrogen (N) have limited their soil sampling to depths either at or just below the deepest tillage treatment in their experiments. This has resulted in an over-emphasis on OC and N changes in the near-surface zones and limited knowledge of crop and tillage system impacts below the maximum depth of soil disturbance by tillage implements. The objective of this study was to assess impacts of long-term (28 years) tillage and crop rotation on OC and N content and depth distribution together with bulk density and pH on a dark-colored Chalmers silty clay loam in Indiana. Soil samples were taken to 1 m depth in six depth increments from moldboard plow and no-till treatments in continuous corn and soybean–corn rotation. Rotation systems had little impact on the measured soil properties; OC content under continuous corn was not superior to the soybean–corn rotation in either no-till or moldboard plow systems. The increase in OC (on a mass per unit area basis) with no-till relative to moldboard plow averaged 23 t ha−1 to a constant 30 cm sampling depth, but only 10 t ha−1 to a constant 1.0 m sampling depth. Similarly, the increase in N with no-till was 1.9 t ha−1 to a constant 30 cm sampling depth, but only 1.4 t ha−1 to a constant 1.0 m sampling depth. Tillage treatments also had significant effects on soil bulk density and pH. Distribution of OC and N with soil depth differed dramatically under the different tillage systems. While no-till clearly resulted in more OC and N accumulation in the surface 15 cm than moldboard plow, the relative no-till advantage declined sharply with depth. Indeed, moldboard plowing resulted in substantially more OC and N, relative to no-till, in the 30–50 cm depth interval despite moldboard plowing consistently to less than a 25 cm depth. Our results suggest that conclusions about OC or N gains under long-term no-till are highly dependent on sampling depth and, therefore, tillage comparisons should be based on samples taken well beyond the deepest tillage depth. 相似文献
148.
Detection and quantification of roundup ready soy in foods by conventional and real-time polymerase chain reaction 总被引:3,自引:0,他引:3
Rott ME Lawrence TS Wall EM Green MJ 《Journal of agricultural and food chemistry》2004,52(16):5223-5232
Transgenic soybean line GTS-40-3-2, marketed under the trade name Roundup Ready (RR) soy, was developed by Monsanto (USA) to allow for the use of glyphosate, the active ingredient of the herbicide Roundup, as a weed control agent. RR soy was first approved in Canada for environmental release and for feed products in 1995 and later for food products in 1996 and is widely grown in Canada. Consumer concern issues have resulted in proposed labeling regulations in Canada for foods derived from genetically engineered crops. One requirement for labeling is the ability to detect and accurately quantify the amount of transgenic material present in foods. Two assays were evaluated. A conventional qualitative Polymerase Chain Reaction (PCR) assay to detect the presence of soy and RR soy and a real-time PCR to quantify the amount of RR soy present in samples that tested positive in the first assay. PCR controls consisted of certified RR soy reference material, single transgenic soybeans, and a processed food sample containing a known amount of RR soy. To test real-world applicability, a number of common grocery store food items that contain soy-based products were tested. For some samples, significant differences in amplification efficiencies during the quantitative PCR assays were observed compared to the controls, resulting in potentially large errors in quantification. A correction factor was used to try to compensate for these differences. 相似文献
149.
Theo M. Syahniar Mira Andriani Muhammad Ridla Erika B. Laconi Nahrowi Nahrowi Anuraga Jayanegara 《Journal of animal physiology and animal nutrition》2021,105(3):419-430
This study aimed to comprehensively evaluate the effects of glycerine supplementation at various concentrations on performance, rumen fermentation, blood metabolites and product characteristics of beef and dairy cattle in vivo by using a quantitative meta-analysis approach. Meta-analysis was performed by integrating a total of 52 studies from 39 articles and 182 treatments into a database. Data were constructed into an intact database and did not distinguish between beef and dairy cattle, except for the parameters of production performance and product characteristics. Data summarized were analysed by using a statistical meta-analysis that employed a fixed effect of glycerine supplementation level and a random effect of various studies for both beef and dairy cattle. Significance of an effect was stated at the probability level of p < .05, and p < .1 was considered as a tendency of significant. Results revealed that there was a linear decrease on dry matter intake (p < .01) and daily gain (p < .05) of beef cattle with the increasing levels of glycerine supplementation. Glycerine supplementation did not decrease milk production of lactating dairy cows. Molar proportion of acetate in the rumen was decreased (p < .001), whereas propionate and butyrate proportions were increased (both at p < .001) by glycerine supplementation. Generally, glycerine did not change nutrient digestibility except that it reduced fibre digestibility (p < .001). Glycerine supplementation linearly lowered triglyceride and NEFA concentrations (both at p < .05) in the blood serum, but not other blood metabolites. Glycerine tended to linearly increase (p < .1) carcass percentage in beef cattle. Increasing dietary glycerine levels decreased milk fat (p < .01) but elevated milk protein (p < .001). Glycerine tended to increase milk lactose (p < .1) by following a quadratic pattern. The proportion of MUFA was increased quadratically by glycerine supplementation (p < .05), whereas glycerine tended to decrease SFA by following a quadratic pattern (p < .1). 相似文献
150.
José A. Amador Richard J. Hull Erika L. Patenaude John T. Bushoven Josef H. Görres 《Water, air, and soil pollution》2007,184(1-4):323-333
Two Elsholtzia haichowensis S. populations, copper-tolerant (TLS) and non-tolerant (HA) ones were studied in hydroponic experiment for the nitrogen assimilation and plant growth under excess Cu conditions. The results demonstrated that there were surely the differences in nitrogen assimilation and plant growth between the two populations. Excess Cu caused evident decreases in the shoot and root biomass and root/shoot biomass ratio in HA population while no significant changes happened in TLS population. In addition, in HA population, excess Cu also induced apparent declines in activities of nitrate reductase (NR, EC 1.6.6.1) and glutamine synthetase (GS, EC 6.3.1.2) in the leaves and roots as well as the contents of nitrate, ammonium and amino acids in the roots. In TLS population, excess Cu did not significantly affect the NR activities in the leaves and roots and the nitrate content in the roots, and apparently elevated the root ammonium and amino acids contents, although it also clearly reduced the GS activities in the leaves and roots. Besides, with the addition of Cu in the culture solution, the Cu contents in the leaves and roots of the two populations markedly increased. But this increase was significantly lower in TLS population than that in HA population; the fact might be partly responsible for the relative stabilization of nitrogen assimilation in TLS population compared to that in HA population. 相似文献