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排序方式: 共有677条查询结果,搜索用时 15 毫秒
671.
Daniela Migliavacca Elba Calesso Teixeira Flávio Wiegand Josete Dani Sanchez Jandyra Fachel Mariana Ribeiro 《Water, air, and soil pollution》2005,167(1-4):91-110
The purpose of the present study is to analyse the chemical composition of bulk and wet atmospheric deposition samples in the Guaíba Hydrographic Basin (GHB), in south Brazil. Samples of bulk and wet deposition were analysed during a 1-year's period (January to December 2002) at three different stations, i.e., 8° Distrito and CEASA stations in the city of Porto Alegre, and Charqueadas station, in Charqueadas city. Conductivity, pH, Cl?, NO3 ?, F?, SO4 2 ?, Na+, K+, Mg2 +, NH4 + and Ca2 + were determined. The pH presented an average value between 4.75 and 7.45. Enrichment factor was characterised based on groups of acid (pH < 5.65) and alkaline (pH > 5.65) samples. For most of the studied ions, EF in bulk deposition was higher in alkaline samples, while in wet deposition there was little difference between acid and alkaline samples. The Multivariate Analysis technique, i.e. the Canonical Correlation Analysis (CCA), determined relationships between the two different data set (chemical and meteorological), identified the source (anthropogenic or natural) of the studied variables. 相似文献
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673.
2‐Alkyl‐3‐methoxypyrazines are potent attractants of florivorous scarabs (Melolonthidae,Cyclocephalini) associated with economically exploitable Neotropical palms (Arecaceae) 下载免费PDF全文
674.
Julia A. Paxson Suzanne M. Cunningham John E. Rush Daniela Bedenice 《Journal of Veterinary Emergency and Critical Care》2008,18(6):601-607
Objective– Failure of passive transfer in neonatal alpacas is often corrected by IV administration of commercial camelid plasma. The goal of this study was to characterize changes in pulmonary function, gas exchange, and cardiovascular parameters associated with IV plasma transfusion. Design– Prospective clinical study. Setting– A university‐based referral hospital. Animals– Eleven clinically healthy alpaca crias (age: 1–18 days) with failure of passive transfer (IgG<8 g/L [800 mg/dL]). Interventions– Thirty milliliters per kilogram of commercial camelid plasma was administered IV over 90 minutes. Before and after the transfusion, the following cardiopulmonary measurements were obtained: arterial blood gas analysis, pulmonary functional residual capacity (FRC), PCV, total plasma protein and echocardiographic M‐mode measures. Additionally, central venous pressure and indirect arterial blood pressure were monitored throughout the plasma transfusion. Measurements and Main Results– The IV plasma transfusion resulted in significantly reduced PCV (−5.4±5.1%), increased total plasma protein (+4±4 g/L [0.4±0.4 g/dL]), elevated central venous pressure and changes in left and right ventricular M‐mode indices, consistent with plasma volume expansion. Transfusion was further associated with a significant increase in arterial oxygen pressure (PaO2) (+11.2±15 mm Hg) and decrease in FRC (−5.6±8.3 mL/kg). Conclusions– IV administration of 30 mL/kg camelid plasma to neonatal crias resulted in measurable plasma volume expansion and a concurrent reduction in FRC. Administration of this quantity of plasma appeared to be safe in healthy neonatal crias. However, changes in lung volume associated with plasma administration may create risks for crias with underlying cardiopulmonary or systemic disease. 相似文献
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676.
Daniela Klein-J?bstl Tim Arnholdt Franz Sturmlechner Michael Iwersen Marc Drillich 《Acta veterinaria Scandinavica》2015,57(1)