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排序方式: 共有453条查询结果,搜索用时 765 毫秒
391.
James W. Swann Oliver A. Garden Claire L. Fellman Barbara Glanemann Robert Goggs Dana N. LeVine Andrew J. Mackin Nathaniel T. Whitley 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(3):1141-1172
Immune‐mediated hemolytic anemia (IMHA) causes severe anemia in dogs and is associated with considerable morbidity and mortality. Treatment with various immunosuppressive and antithrombotic drugs has been described anecdotally and in previous studies, but little consensus exists among veterinarians as to the optimal regimen to employ and maintain after diagnosis of the disease. To address this inconsistency and provide evidence‐based guidelines for treatment of IMHA in dogs, we identified and extracted data from studies published in the veterinary literature. We developed a novel tool for evaluation of evidence quality, using it to assess study design, diagnostic criteria, explanation of treatment regimens, and validity of statistical methods. In combination with our clinical experience and comparable guidelines for humans afflicted with autoimmune hemolytic anemia, we used the conclusions of this process to make a set of clinical recommendations regarding treatment of IMHA in dogs, which we refined subsequently by conducting several iterations of Delphi review. Additionally, we considered emerging treatments for IMHA in dogs and highlighted areas deserving of future research. Comments were solicited from several professional bodies to maximize clinical applicability before the recommendations were submitted for publication. The resulting document is intended to provide clinical guidelines for management of IMHA in dogs. These guidelines should be implemented pragmatically, with consideration of animal, owner, and veterinary factors that may vary among cases. 相似文献
392.
393.
Purpose
The aims of the study were to evaluate the effect of combined sewer overflows (CSO) and storm water drains (SWD) on metal bioavailability in small urban streams in Prague and to evaluate levels of metals in water, sediment, and macroinvertebrates. The following working hypotheses were adopted: (a) sites dominantly affected by SWD are less polluted by metals, and (b) sites dominantly affected by SWD have higher bioavailability of metals.Materials and methods
Physical and chemical parameters (pH, conductivity, NO3-N, NH4-N, COD, alkalinity, and water hardness) and concentrations of the metals Cu, Zn, Pb, Ni, and Cr were determined in samples of water and sediment at five to six sites on four target streams—Záti?ský Creek, Ko?íkovský Creek, Boti? Creek, and Rokytka Creek—three to five times per year during the period 2002–2004. The sites from all studied creeks were categorized into five groups according to the prevailing type of urban drainage impact. Macroinvertebrates were sampled and analyzed for metals at each site for a period of 1 month. The concentration patterns of metals were interpreted by partition coefficient (Kd), hazard quotient (HQ), cumulative criterion unit (CCU), and biota sediment accumulation factor (BSAF).Results and discussion
Concentrations of metals in water as well as in sediment at sites receiving water from SWD were lower than at sites where creeks receive water from CSO, except for Pb. Concentrations of Cu, Zn, and Pb in sediment were higher at sites affected by CSO. Concentrations of metals in aquatic macroinvertebrates, expressed as BSAF, indicated higher values at sites affected by SWD. Frequencies of high BSAF (>1) were lower in CSO compared to SWD. This finding was explained by (a) a decrease of pH on SWD sites compared to the increase of pH on CSO sites during rain events, (b) a greater resuspension of sediment at SWD sites during rain events, and (c) an abundance of organic matter in CSO available for sorption of metals and a corresponding reduction of their bioavailability.Conclusions
In the study area, the type of urban drainage affects the bioavailability of metals—while SWD increase metal bioavailability, CSO cause its decrease. The sediments in SWD sites do not indicate risk to the benthic community according to the applied environmental quality standards. Water and sediment in creeks affected by SWD are less polluted by metals. Both working hypotheses were therefore supported.394.
Suppression of Soil Microorganisms by Emissions of a Magnesite Plant in the Slovak Republic 总被引:1,自引:0,他引:1
Guido Kautz Martin Zimmer Peter Zach Ján Kulfan Werner Topp 《Water, air, and soil pollution》2001,125(1):121-132
In April 1996, we collected soil samples in thevicinity of a magnesite plant at Lubeník, southernSlovakia, and screened them for soil microbial biomassand activity. Six investigated sites were chosen alonga transect, with distances ranging from 600 to 8000 mfrom the plant, to represent a gradient ofintoxication. Soil microbial cellulase activity,respiration, biomass, metabolic quotient of the soilmicrobiota, and numbers of platable fungi increasedwith increasing distance from the plant, i.e.decreasing degree of intoxication. The observedgradients of soil microbial characteristics of theinvestigated sites reflect the physico-chemical soilparameters and the floristic characteristics of thesesites, and may be used to predict transitory changesduring amelioration. 相似文献
395.
Zimmer M, Schreer JF, Power M. Seasonal movement patterns of Credit River brown trout (Salmo trutta).Ecology of Freshwater Fish 2010: 19: 290–299. © 2010 John Wiley & Sons A/S Abstract – Movement habits in riverine populations of brown trout vary among watersheds. Thus it is important to identify factors influencing differences in individual behaviour so as to improve the information resource base available for the design of river‐specific management strategies. Such information is particularly needed in the rapidly urbanising watersheds of eastern North America where relatively little is known about anthropogenic influences on brown trout populations. In this study, we examined the influence of water temperature on brown trout behaviour in the Credit River in south‐central Ontario, Canada with respect to seasonal movement patterns. Observed patterns of movement were also correlated with variations in river discharge and habitat quality. Forty‐three radio‐tagged, adult brown trout were tracked in a confined 39.8 km portion of the Credit River from 15 May 2002 to 28 July 2003. Fish were captured in three sections of the river that differed in distance downstream and habitat quality. Fish size had little impact on movement patterns. However, there was considerable variation in seasonal movement with upstream movements to summer positions, maintenance of summer positions, downstream and often extensive movements in fall. Also observed was maintenance of winter positions and repeated upstream movements in late spring‐early summer to previously used summer positions. The elaborate movement behaviour in the Credit River population was attributed to seasonal changes in thermal habitat quality. Fish tagged in less suitable thermal habitats moved significantly more than fish from more suitable thermal habitats. 相似文献
396.
Fontaine J Zimmer U Moughan PJ Rutherfurd SM 《Journal of agricultural and food chemistry》2007,55(26):10737-10743
The suitability of the homoarginine reaction for determining the reactive lysine in soy products and corn distillers dried grain with solubles (DDGS) was tested. For this purpose, some batches were subjected to deliberate heat damage for up to 30 min in an autoclave with 135 degrees C hot steam, and the samples were analyzed for total lysine and reactive lysine. In addition, 84 samples of common soy and 80 samples of corn DDGS were tested for their content of total and reactive lysine, and the contents were compared with those of the autoclave tests. For soy products conclusive results were obtained. In the case of heat treatment, both total lysine and reactive lysine decrease, but the latter is clearly a more sensitive indicator of lysine damage. Most normal products are quite similar, with toasting-induced damage to reactive lysine of ca. 15% compared to untoasted beans. The cause of the constantly occurring residual lysine after guanidination and the poorer reaction balance in the case of damage were explained. For common DDGS samples, however, less favorable results were obtained. Reactive and total lysine decreased almost in parallel due to heat damage, showing a great gap between them. Results showed indeed that variation of total and reactive lysine in DDGS is high, proving that its production conditions are not yet optimal for a feed ingredient. 相似文献
397.
398.
Zimmer C 《Science (New York, N.Y.)》2001,293(5537):1974-1977
399.
Spehr M Gisselmann G Poplawski A Riffell JA Wetzel CH Zimmer RK Hatt H 《Science (New York, N.Y.)》2003,299(5615):2054-2058
Although it has been known for some time that olfactory receptors (ORs) reside in spermatozoa, the function of these ORs is unknown. Here, we identified, cloned, and functionally expressed a previously undescribed human testicular OR, hOR17-4. With the use of ratiofluorometric imaging, Ca2+ signals were induced by a small subset of applied chemical stimuli, establishing the molecular receptive fields for the recombinantly expressed receptor in human embryonic kidney (HEK) 293 cells and the native receptor in human spermatozoa. Bourgeonal was a powerful agonist for both recombinant and native receptor types, as well as a strong chemoattractant in subsequent behavioral bioassays. In contrast, undecanal was a potent OR antagonist to bourgeonal and related compounds. Taken together, these results indicate that hOR17-4 functions in human sperm chemotaxis and may be a critical component of the fertilization process. 相似文献
400.
Parameters for evaluating both the soil organic matter quantity (total organic C [TOC]) and quality (hot water extractable C [HWC], hydrophobic and hydrophilic components, soil hydrophobicity) were determined in soil samples taken from selected plots of 13 field experiments under different soil and climatic conditions in the period 2004–2008. Four variants were selected in each experiment: non-fertilized control (Nil), mineral fertilized variant (NPK), farmyard manured variants (FYM) and organic and mineral fertilized variants (FYM + NPK). The TOC and HWC content of topsoil differed mainly as a result of the site conditions. Both organic and mineral fertilization increased the TOC content of soil; the percentage increase in the HWC content was greater than that for the TOC content. Mineral and organic fertilization increased the hydrophobic organic component content but not the hydrophilic organic component content. A significant positive correlation was found between hydrophobic organic components and HWC content (R = 0.746, P < 0.01). Hydrophilic organic component content was highly significantly correlated with the TOC content (R = 0.728, P < 0.01). Soil hydrophobicity was affected by soil texture and clay content, and a positive effect of long-term organic fertilization on soil hydrophobicity, and thereby soil stability, was determined. 相似文献