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11.
Martina Fabbi Antonella Volta Fausto Quintavalla Elena Zubin Sabrina Manfredi Filippo M. Martini Luciana Mantovani Mario Tribaudino Giacomo Gnudi 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(12):1163-1166
A 7-year-old dog was presented with a history of an open lesion on the right thoracic wall, discharging honey-like fluid and small stones. Ultrasonography and computed tomographic fistulography identified a cholecystocutaneous fistula; cholecystectomy was curative. Veterinarians should consider this disease in patients with long-term discharging lesions on the right thoracic or abdominal wall. 相似文献
12.
研究不同时期接种丛枝菌根真菌根内球囊菌(Glomus intraradices,GI)对大棚土壤栽培黄瓜植株生长、产量及营
养品质的影响。结果表明:黄瓜不同时期接种GI 对其生长均有促进作用,与不接菌的对照相比,播种时接菌和移栽时接菌处理使黄瓜的单株产量分别提高54%、34%;播种时接菌处理的黄瓜叶片的叶绿素含量比对照显著提高了14.7%~17.7%;播种时接菌和移栽时接菌的黄瓜硝酸盐含量较对照分别下降了9.4% 和15.0%,总糖含量分别比对照提高了8.9% 和7.1%;移栽时接菌处理的黄瓜粗蛋白含量比对照提高了4.6%;播种时接菌和移栽时接菌显著提高了黄瓜VC 含量。表明接种GI 对黄瓜生长和产量品质具有一定的改善作用。 相似文献
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Quantifying the most important mechanisms of acid buffering in carbonate-free soils From the release of cations from the soil matrix during pH-stat-titrations, characteristic values for assessing buffer rates were derived separately for single elements. Recorded buffer reactions became almost exclusively apparent in the release of Al and Fe, however the contribution of Fe to the total turnover only amounted to 1–3%. The release of each element and of DOC in the course of time was due to the overlapping of two first-order reactions, respectively. In the fast initial reaction all measured elements were released at nearly the same velocity, whereas in the 2nd, slower reaction the rate of Al-release corresponded to that of DOC but was at least seven times higher than that of Fe. Correlations between the maxima of release and soil chemical properties revealed a dominating contribution of organically bound Al (Alp) to proton buffering. It is assumed that also the amount of Fe released is originating in organic complexes. 相似文献
16.
Forest fungi not only have important functions within the forest ecosystem, but picking their fruit bodies is also a popular past time, as well as a source of income in many developing and developed countries. The expansion of commercial harvesting in many parts of the world has led to widespread concern about overharvesting and possible damage to fungal resources. In 1975, we started a field research project to investigate the effects of mushroom picking on fruit body occurrence. The three treatments applied were the harvesting techniques picking and cutting, and the concomitant trampling of the forest floor. The results reveal that, contrary to expectations, long-term and systematic harvesting reduces neither the future yields of fruit bodies nor the species richness of wild forest fungi, irrespective of whether the harvesting technique was picking or cutting. Forest floor trampling does, however, reduce fruit body numbers, but our data show no evidence that trampling damaged the soil mycelia in the studied time period. 相似文献
17.
This study was set up for validation of a regression model to predict mortality in the terrestrial earthworm Aporrectodea caliginosa following exposure to copper. This model was derived from a terrestrial biotic ligand model and incorporates the protective effects of H+ and Na+ on copper toxicity.Three soil sets were used for the experiments, all of which had a different copper contamination history over more than 20 years and were considered to be aged field soils. The soils were characterized by analysis of various copper pools in the solid phase and in the pore water, analysis of physical and chemical soil properties and by regression analysis. Measured and calculated copper activities (expressed as pCu) correlated reasonably well. Measured copper activities correlated with the total copper concentration in the pore water and the pH. The organic matter in the solid phase had no influence on the pCu in these soil sets.Earthworms were exposed to the soils for 28 days, after which survival was scored. Observed earthworm mortality after 28-days exposure was plotted as a function of the log-transformed difference between predicted (log10 transformed) LC50-values and measured values of pCu for validation of the regression model. The results obtained were in agreement with the assumption that mortality is to be observed in those soils where the predicted LC50 exceeds the measured pCu. However, a structural underestimation of toxicity was apparent, which is most likely due to mixture effects related to the presence of additional substances in field soils. Nevertheless, the trend of the results in the validation tests demonstrates that the newly developed toxicity model is a useful tool in predicting lethality of copper contamination to earthworms in field soils. 相似文献
18.
Verónica Nilda Ispizúa Irma Rosana Guma Sergio Feingold Andrea Martina Clausen 《Genetic Resources and Crop Evolution》2007,54(8):1833-1848
Andean potato varieties are cultivated in the northwest of Argentina and constitute the most important staple food for the
local farmers. The genetic diversity of 155 accessions conserved at the Genebank of Balcarce (INTA) was tested using four
microsatellites. Three commercial potato varieties of Tuberosum group and one accession of Curtilobum group were used as outgroups.
The presence of bands was scored for each microsatellite and for each accession and the data were analysed by principal coordinate
analysis. The polymorphism information content was obtained for each molecular marker from banding patterns. Analysis of molecular
variance was carried out with a variable number of accessions for each landrace, from different departments and sites within
departments. More than one genotype was detected in the majority of the potato landraces. Some accessions within each landrace
did not differentiate. AMOVA revealed that most of the genetic variation occurred among sites within departments and among
local varieties. These findings are discussed considering the agricultural practices carried out in the Andean farming system. 相似文献
19.
Severe stream water acidification occurs at higher altitudes (> 600 m a.s.l.) in the Western Harz mountains in Northern Germany. Since 1986 an interdisciplinary research team has followed the fate of pollutants in the 50 km2 catchment of an important drinking water reservoir (Lake Söse). An acidification experiment has estimated the role of the remobilization of selected elements from the lake sediments via acidification. Aquaria were used to monitor the effects of a stepwise acidification (from the natural pH of 6.5 to 5.0, 4.0 and 3.0) of the water column over a reconstituted sediment layer. The sediment chemistry has been analyzed before and after the acidification by XRF. The water chemistry was sampled at time intervals and analyzed by ICP-MS. With a pH drop from 6.5 to 3.0, many elements increase in concentration in the water of the acidified basins. Enrichment factors were: Al (5000), Ba (10), Cd (220), Co (800), Cu (170), Ni (90), Pb (5000), and Zn (400). This corresponds fairly well with the field data. Al, Cd, Fe, Mn, and Pb exceed German drinking water limits at pH 4.0. The combined high concentrations (μg L?1) of Al (1000–2600), Cd (2–4), Cu (4–7), Pb (30–60), and Zn (100–300) in the water column of the acidified streams are not only toxic for fish but also for many other aquatic organisms. Chemical changes in the sediment are not significant within the experimental setup. 相似文献
20.
Hellal F Hurtado A Ruschel J Flynn KC Laskowski CJ Umlauf M Kapitein LC Strikis D Lemmon V Bixby J Hoogenraad CC Bradke F 《Science (New York, N.Y.)》2011,331(6019):928-931
Hypertrophic scarring and poor intrinsic axon growth capacity constitute major obstacles for spinal cord repair. These processes are tightly regulated by microtubule dynamics. Here, moderate microtubule stabilization decreased scar formation after spinal cord injury in rodents through various cellular mechanisms, including dampening of transforming growth factor-β signaling. It prevented accumulation of chondroitin sulfate proteoglycans and rendered the lesion site permissive for axon regeneration of growth-competent sensory neurons. Microtubule stabilization also promoted growth of central nervous system axons of the Raphe-spinal tract and led to functional improvement. Thus, microtubule stabilization reduces fibrotic scarring and enhances the capacity of axons to grow. 相似文献