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121.
Polycyclic Aromatic Hydrocarbons (PAHs) in soils of the Münster (Westfalia) irrigation fields From 1901 to 1975 municipal sewage waters with a daily amount of finally about 40.000 m3 were seeped in the irrigation fields of the city of Münster (Westfalia). Soil samples of former seeped sites and non-seeped neighbour sites have been examined with regard to 6 polycyclic aromatic hydrocarbons (PAHs) of the German “drinking water regulation”. The irrigation caused an enrichment of PAH in the topsoils of the former irrigation basins up to an average concentration of 0,57 mg PAH/kg soil, while the topsoils outside of the irrigation fields show an average concentration of only 0,14 mg PAH/kg soil. Significant correlations between different soil properties, e.g. the organic matter content, and the concentration of PAHs are not evident. After termination the irrigation of sewage water, single irrigation bassins were filled with substratum, which is contaminated with scoriaceous materials. The average PAH concentration of such an area amounts to 7 mg PAH/kg topsoil. The PAH distribution in a soil profile shows a decreasing concentration by depth but a clear enrichment in oxidized gleyic horizons (Go) of different age. Probably the PAHs were leached under recent conditions by chemical bond to dissolved organic carbon (DOC) and finally adsorbed by Fe oxides. Since the end of irrigation Fluoranthene, the most mobile PAH compound, was leached down to 110 cm depth. A contamination of the superficial groundwater at such sites cannot be excluded.  相似文献   
122.
Accumulation soils like those known as “Ockererde” are not yet represented in the German and in international soil‐classification systems, even though they represent important members of catenas found in humid low‐mountain areas influenced by the translocation of interpedon matter. Currently, this soil is referred to as “(Hang‐)Oxigley”, though this does not take into account its water and matter dynamics. Six representative catenas in the Black Forest (SW Germany) will be used to describe the occurrence, extent, and properties of the accumulation‐affected “Ockererde” derived from a variety of parent materials at specific altitudes. On the basis of their morphological, chemical, and physical properties as well as matter dynamics, it is possible to distinguish “Ockererde” clearly from soil units with similar characteristics (“Lockerbraunerde”, Andosols). Finally, suggestions will be given for the classification of “Ockererde”.  相似文献   
123.
The influence of thermal treatment and light exposure on degradation and isomerization of the predominant carotenoids (lutein and beta-carotene) occurring in green leafy vegetables was assessed. The effect of lipid addition on carotenoid stability was also evaluated. For the first time, the stabilities of pure carotenoids and chloroplast-bound carotenoids were compared. Besides degradation, heating caused carotenoid isomerization in all samples. Whereas pure carotenoids favor 13-cis isomers, in native chloroplasts and heated chloroplasts 9-cis isomers were predominant. Illumination of freshly prepared chloroplast isolates caused an initial increase in the level of lutein (9.6%) and beta-carotene (29.8%), while pure carotenoids exhibited time-dependent degradation. The addition of lipids to chloroplast preparations had the reverse effects on the retention of both carotenoids after heating; isomerization was not significantly affected. It was demonstrated that carotenoid stability has to be evaluated for every individual pigment in its genuine environment. Stability data based on model systems (e.g., pure carotenoids) may not be transferred to complex food matrices without intensive investigation.  相似文献   
124.
A method for the determination of beta-carotene, lutein, and zeaxanthin including their cis-isomers and alpha-carotene in commercial dietary supplements by HPLC has been developed. The study comprises 11 oral dosage forms, including 9 soft gelatin capsules, 1 dragée, and 1 effervescent tablet formulation. The capsule content was extracted with an acetone-hexane mixture, and the gelatin shell was digested with papain to release carotenoids that had migrated into the coat. Sample preparation for tablets and dragées was carried out as described for the capsule content. Extraction recoveries exemplified for all-trans-beta-carotene and all-trans-lutein were 95 +/- 5% and 93 +/- 2%, and 95 +/- 2% and 79 +/- 5% after enzymatic treatment, respectively. Apart from all-trans-beta-carotene, its 9-cis- and 13-cis-isomers were detected in all samples, whereas no evidence for cis-isomerization of lutein and zeaxanthin could be obtained. Migration of carotenoids into the shells was only observed in the case of beta-carotene. With the exception of one preparation, the beta-carotene contents determined exceeded the dosage specified on the label by up to 48%, which results from stability overages necessary to compensate for losses during storage.  相似文献   
125.
Three newly formed pigments were detected and isolated from a 2-year-old Port wine through TSK Toyopearl HW-40(S) gel column chromatography and characterized by UV-visible spectrophotometry, NMR, and mass spectrometry (ESI/MS). (1)H NMR and (13)C NMR data for these pigments obtained using 1D and 2D NMR techniques (COSY, NOESY, gHSQC, and gHMBC) are reported for the first time. The structure of the pigments was found to correspond to the vinyl cycloadducts of malvidin 3-coumaroylglucoside bearing either a procyanidin dimer or a flavanol monomer ((+)-catechin or (-)-epicatechin). Additionally, conformational analysis was performed for one of these newly formed pigment using computer-assisted model building and molecular mechanics. A chemical nomenclature is proposed to unambiguously name this new family of anthocyanin-derived pigments.  相似文献   
126.

Background

Numerous signaling pathways function in the brain ventricular system, including the most important - GABAergic, glutaminergic and dopaminergic signaling. Purinergic signalization system - comprising nucleotide receptors, nucleotidases, ATP and adenosine and their degradation products - are also present in the brain. However, the precise role of nucleotide signalling pathway in the ventricular system has been not elucidated so far. The aim of our research was the identification of all three elements of purinergic signaling pathway in the porcine brain ventricular system.

Results

Besides nucleotide receptors on the ependymocytes surface, we studied purines and pyrimidines in the CSF, including mechanisms of nucleotide signaling in the swine model (Sus scrofa domestica). The results indicate presence of G proteins coupled P2Y receptors on ependymocytes and also P2X receptors engaged in fast signal transmission. Additionally we found in CSF nucleotides and adenosine in the concentration sufficient to P receptors activation. These extracellular nucleotides are metabolised by adenylate kinase and nucleotidases from at least two families: NTPDases and NPPases. A low activity of these nucleotide metabolising enzymes maintains nucleotides concentration in ventricular system in micromolar range. ATP is degraded into adenosine and inosine.

Conclusions

Our results confirm the thesis about cross-talking between brain and ventricular system functioning in physiological as well as pathological conditions. The close interaction of brain and ventricular system may elicit changes in qualitative and quantitative composition of purines and pyrimidines in CSF. These changes can be dependent on the physiological state of brain, including pathological processes in CNS.  相似文献   
127.
Transcutaneous PO2-measurement has been thought being non practicable in veterinary medicine. Consequently, the measuring method has been slightly modified. PO2 was taken from the mucous membrane of the lower surface of tongue. This has been practised in 6 dogs and 10 calves. We achieved a significant correlation between transmucosal and arterial PO2, taken simultaneously in each animal. Considering these results the use of transmucosal measurement may be recommended for a trend-measuring in anesthesized animals. Nevertheless, there has to be pointed out that transmucosal PO2 has to be interpreted regarding its complexity.  相似文献   
128.
129.
Monoclonal Gammopathy in a Dog With Visceral Leishmaniasis   总被引:1,自引:0,他引:1  
One dog with visceral leishmaniasis associated with monoclonal gammopathy is described. Most dogs with visceral leishmaniasis present with hyperproteinemia due to a polyclonal gammopathy, but the possibility of monoclonal gammopathy must be considered. Because dogs accompany their owners when they travel, the diagnosis of leishmaniasis should be considered if an animal with monoclonal gammopathy has visited an area where the disease is endemic. The observation of Leishmania in the macrophages of a bone marrow, lymph node smear, or skin biopsy specimen is diagnostic.  相似文献   
130.
Microbial biomass C and soil respiration measurements were made in 17–20 yr old soils developed on sluiced and tipped coal‐combustion ashes. Topsoil (0–30 cm) and subsoil (30–100 cm) samples were collected from three soil profiles at two abandoned disposal sites located in the city area of Halle, Saxony‐Anhalt. Selected soil physical (bulk density and texture) and chemical (pH, organic C, total N, CEC, plant available K and P, and total Cd and Cu) properties were measured. pH values were significantly lower while organic C and total N contents and the C : N ratio were significantly higher in the topsoil than in the subsoil indicating the effects of substrate weathering and pedogenic C accumulation. Likewise, microbial biomass C, K2SO4‐extractable C, and soil respiration with median values of 786 μg biomass C g–1, 262 μg K2SO4‐C g–1, and 6.05 μg CO2‐C g–1 h–1, respectively, were significantly higher in the topsoil than in the subsoil. However, no significant difference was observed in metabolic quotient between the topsoil and the subsoil. Metabolic quotient with median values of 5.98 and 8.54 mg CO2‐C (g biomass C)–1 h–1 for the 0–30 cm and 30–100 cm depths, respectively, was higher than the data reported in the literature for arable and forest soils. Microbial biomass C correlated significantly with extractable C but no relationship was observed between it and total N, Cd, and Cu contents, as well as plant‐available K and P. We conclude that the presence of the remarkable concentration of extractable C in the weathered lignite ashes allowed the establishment of microbial populations with high biomass. The high metabolic quotients observed might be attributed to the heavy‐metal contamination and to the microbial communities specific to ash soils.  相似文献   
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