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排序方式: 共有2481条查询结果,搜索用时 10 毫秒
41.
Identification of ammonia,chlorine, and diazinon as toxicants in a municipal effluent 总被引:4,自引:0,他引:4
Lawrence P. Burkhard James J. Jenson 《Archives of environmental contamination and toxicology》1993,25(4):506-515
A toxicity identification evaluation (TIE) was performed on a municipal effluent, and three toxicants were identified, ammonia, chlorine, and diazinon. Ammonia and chlorine were the only toxicants present at toxic concentrations in all sample sets, and diazinon was present in toxic concentrations in one of the effluent sample sets. Six effluent sets taken over an 8-month period were evaluated in this TIE. The nonpolar toxicity, primarily due to diazinon, was intermittent since it was present at toxic concentrations only once in the 8-month time period.This report illustrates the types of data and logic used in performing a TIE which contains common municipal toxicants. Emphasis in this report was place on the data needed for generating the weight of evidence in toxicant confirmation, Phase III, to support the suspect toxicants identified in the TIE process. Multiple Phase III manipulations, when applied to numerous effluent samples, provided consistent results for generating the weight of evidence for the confirmation of ammonia and chlorine as the primary causes of toxicity in this effluent. 相似文献
42.
Daniela Gmez Atria Brian T. Gaudette Jennifer Londregan Samantha Kelly Eric Perkey Anneka Allman Bhaskar Srivastava Ute Koch Freddy Radtke Burkhard Ludewig Christian W. Siebel Russell J.H. Ryan Tanner F. Robertson Janis K. Burkhardt Warren S. Pear David Allman Ivan Maillard 《The Journal of clinical investigation》2022,132(13)
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Pantelis D Beissel A Kahl P Vilz TO Stoffels B Wehner S Kalff JC 《International journal of colorectal disease》2011,26(6):737-746
Purpose
Prevention of perioperative activation of intestinal muscularis macrophages is a promising intervention to avoid post-traumatic gastrointestinal tract dysfunction. However, impaired macrophage function could have deleterious consequences on anastomotic healing, especially in complications aggravating the healing process itself, such as infectious problems either as preexisting local inflammation or infection (e.g., complicated diverticulitis) or endotoxemia due to early postoperative infections (e.g., pneumonia). Aim of this study was to investigate colonic anastomotic healing in macrophage-depleted mice in the presence of endotoxemia. 相似文献46.
47.
Franz Wingen Thomas Eichmann Christian Manegold Burkhard Krempien 《Journal of cancer research and clinical oncology》1986,111(1):35-41
Summary This report is concerned with therapeutic studies utilizing new bisphosphonic acids on tumor-induced osteolytic metastases. The bone metastases on SD rats were induced by intraarterial and intraosseous transplantation of Walker carcinosarcoma 256B ascites cells. The treatment was carried out using disodium-3-amino-1-hydroxypropylidene-1,1-bisphophonate (APD), diglycidyl-[3-(3,3-bisphosphono-3-hydroxy-propylamino)-2-hydroxypropyl-]urazol-Na2 (DDU) and 1,2,4-triglycidylurazol (TGU). The extent of bone metastases was determined by X-ray on the 5th and 10th days following tumor inoculation, as well as both microradiographically and histologically upon termination of the experiment.High dose DDU produced a clear reduction of the tumor osteolysis, but these positive results were surpassed using APD. The best results were achieved by pretreatment with APD 24 h prior to tumor inoculation.Dedicated to Professor Dietrich Schmähl on the occasion of his 60th birthday 相似文献
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Diana Sonntag Sarah Schneider Noreen Mdege Shehzad Ali Burkhard Schmidt 《Nutrients》2015,7(10):8565-8576
An increased consumption of energy-dense, nutrient-poor food and beverages as a result of a changing obesogenic environment contributes substantially to the increasing prevalence of childhood overweight and obesity. This paper reviews the nature and extent of food industry influences which expose children to commercial influences and thus might affect unhealthy dietary behaviour and finally contributes to obesity. A systematic search of nine electronic databases (including PubMed, PsycINFO, EconLit) and reference lists of original studies and reviews using key search terms identified 1900 articles. Of these only thirty-six articles met the inclusion and quality criteria. A narrative synthesis of the reviewed studies revealed six key obesogenic environments by which the food industry possibly influences obesity-related dietary behaviours in young children. These were schools, retailers, mass media “television”, mass media “internet”, home and promotional campaigns. Identifying these obesogenic environments is critical for monitoring and controlling the food industry, the development of effective environmental-level interventions to prevent childhood overweight and obesity and to identify knowledge gaps to be addressed in future research to support informed decisions of policy makers. 相似文献
50.
Sydow K Hornig B Arakawa N Bode-Böger SM Tsikas D Münzel T Böger RH 《Vascular medicine (London, England)》2004,9(2):93-101
Hyperhomocysteinemia is associated with an enhanced risk for cardiovascular disease. Patients with peripheral arterial disease (PAD) show an increased prevalence of hyperhomocysteinemia. A decreased biological activity of nitric oxide (NO) may contribute to homocysteine-associated endothelial dysfunction. This study was designed to investigate whether elevated levels of the endogenous NO synthase inhibitor asymmetric dimethylarginine (ADMA) are involved in endothelial dysfunction in patients with chronic hyperhomocysteinemia and PAD. A total of 76 patients (58 males and 18 females; mean age 65.2 +/- 2.0 years) with PAD were included in the analysis and characterized according to demographic variables and cardiovascular risk factors. Flow-dependent vasodilation (FDD) was determined by high-resolution ultrasound in the radial artery. Total plasma homocysteine (plasma tHcy) and ADMA levels were measured by HPLC. Urinary nitrate was quantified using gas chromatography-mass spectrometry. Patients with plasma tHcy in the highest tertile (n = 27; i.e. > 10.6 micromol/l) had a mean plasma level of 14.4 +/- 1.21 mol/l compared with 9.9 +/- 0.1 micromol/l in those patients in the middle tertile (n = 22; p < 0.05) and 9.4 +/- 0.1 micromol/l in those in the lowest tertile (n = 27; i.e. <9.6 micromol/l; p < 0.05). The hyperhomocysteinemic individuals (highest tertile) had a significantly decreased FDD compared with healthy age-matched controls (n = 15) (7.6 +/- 1.0 vs 13.0 +/- 0.4%; p < 0.05), higher plasma ADMA concentrations (4.0 +/- 0.3 vs 2.6 +/- 0.3 micromol/l; p < 0.05), and a lower urinary nitrate excretion rate (89.5 +/- 13.4 vs 131.3 +/- 17.9 micromol/mmol creatinine; p < 0.05) compared with patients with plasma tHcy in the lowest tertile. Multivariate regression analysis including plasma tHcy, ADMA, total cholesterol, diabetes mellitus, smoking, and systolic blood pressure revealed ADMA as the only significant factor determining FDD (p < 0.05). In conclusion, we demonstrated a stronger relationship between impaired endothelial function and elevated ADMA levels in comparison with plasma tHcy concentrations in patients with PAD and chronic hyperhomocysteinemia. This may raise the question of whether different therapeutical options that interact indirectly with plasma tHcy, i.e. treatment with ACE inhibitors and AT1-receptor blockers to reduce ADMA plasma concentrations or L-arginine, could be a beneficial tool for treating patients with hyperhomocysteinemia. 相似文献