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61.
Chemical properties of forest soils in the pleistocene of Northwest Germany and their classification based on soil buffering systems In order to characterize the chemical characteristics of forest soils of Hamburg, 800 soil samples and 400 root samples from 172 sites were used to obtain suitable soil chemical and ecochemical parameters. A strong and deep reaching soil acidification was observed on all sites with exception of those on till. The sulfate concentration in the equilibrium soil solution allows the conclusion that deposition of acid plays a significant role in this acidification. Classification of sites based on edaphic factors did not provide useful information on the chemical status of soils. However, grouping of soil horizons using pH measured in 0.01 M CaCl2 lead to a stratification according to the soil buffering systems. Distinction between the exchanger and the aluminium buffer ranges was, however, not quite satisfactory. 相似文献
62.
Ulrich Ammer 《European Journal of Forest Research》1977,96(1):2-2
Ohne Zusammenfassung 相似文献
63.
Bleul UT Schwantag SC Bachofner C Hässig MR Kähn WK 《Journal of the American Veterinary Medical Association》2005,226(7):1119-1123
OBJECTIVE: To determine milk flow, somatic cell counts (SCCs), and the incidence of clinical mastitis in cows that had undergone theloresectoscopy for treatment of teat stenosis caused by mucosal detachment in the region of the streak canal or Fürstenberg's rosette. DESIGN: Retrospective study. ANIMALS: 52 cows with teat stenosis that were treated via theloresectoscopy. PROCEDURE: Medical records of eligible cows were reviewed. Additional data regarding milking ease, SCC, development of clinical mastitis of the affected gland, and whether the cow remained in the herd were collected via owner-completed questionnaires. RESULTS: 49 of 52 questionnaires were completed. At referral, teat sinusitis was diagnosed in 29 of 52 cows. Milk flow was normal in 38 of 41 treated teats at discharge and in 24 of 40 during the next lactation. Thirteen of 49 cows were culled during the next lactation because of abnormal udder health. High SCC and teat sinusitis at referral and development of clinical mastitis during the 10-day period after surgery resulted in high SCCs in the remainder of the current lactation. The incidence of clinical mastitis during the remainder of the current and during the next lactation was higher in cows that had teat sinusitis at the time of surgery, compared with those that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Teat stenoses resulting from mucosal lesions in the region of the streak canal or Fürstenberg's rosette may be successfully treated via theloresectoscopy. Inflammation of the teat sinus and gland at the time of surgery may adversely affect udder health. 相似文献
64.
Lok JB Washabau RJ Heaney K Nolan TJ Hendrick MJ Neumann NR Ulrich M 《Veterinary parasitology》2005,133(2-3):233-241
The purpose of this study was to assess the efficacy of moxidectin sustained release injectable for dogs (moxidectin SR, Fort Dodge Animal Health) in protecting growing puppies from experimental infection with the heartworm, Dirofilaria immitis, six months after treatment. The study involved 27 puppies, approximately 12 weeks of age at the beginning of the study, with nine puppies in each of three size classes. The small breed class included eight Pekingese and one purpose-bred small breed mongrel; the medium breed class included nine purpose-bred mongrels, and the large breed class included nine puppies with an anticipated adult weight >or=30-35 kg. Both genders were included with no attempt made to have equal numbers of male and female puppies. Puppies were blocked by weight within each size class and randomly assigned to three treatment groups of nine dogs. On Day 0, pups in two groups were injected subcutaneously with moxidectin SR, dosed to deliver 0.17 mg moxidectin/kg b.w. The third group was injected with sterile saline. Personnel making observations were blinded to the treatment status of the animals. Following treatment, puppies were observed for signs of adverse local and systemic reactions. Puppy weights and serum moxidectin levels were also monitored. On Day 180, puppies in all treatment groups were inoculated subcutaneously with 50 third-stage larvae of D. immitis. On Days 348 and 349, puppies were euthanatized and necropsied. Hearts and lungs were examined for adult heartworms. All animals in the saline control group were infected with an arithmetic mean of 39.22 adult heartworms each. Seventeen of 18 dogs in the moxidectin SR-treated groups were uninfected. One treated puppy was infected with a single adult heartworm. This infected individual was from the large breed size class and had the second highest percent increase in body weight. Based on arithmetic means, the heartworm recovery from all treated puppies represents a 99.86% reduction relative to the saline control. There were no adverse local or systemic reactions to treatment in any animal. 相似文献
65.
R. Ulrich 《Plant foods for human nutrition (Dordrecht, Netherlands)》1969,19(1-3):i-v
66.
Two small creeks, tributaries of the River Ruhr near Schwerte, Federal Republic of Germany, were investigated to reveal the regional agricultural and non-agricultural sources of pesticide inputs and the main pathways to surface water. In addition, the receiving water was monitored for pesticides. The watersheds are situated at the northern margin of the Rhenian Schiefergebirge, a highland landscape in North-Rhine-Westphalia. Solid carboniferous shale is covered by a shallow layer of quaternary unconsolidated rock (porous aquifer thickness <5 m). Occurrence of herbicides such as chlortoluron, isoproturon and terbuthylazine in surface water could be due to their broad agricultural application in regional dominant crops, such as barley, wheat and maize. Occurrence of diuron and glyphosate results from their use in residential settlements and industrial areas as well as from weed control on railway tracks. Atrazine concentrations up to 0.8 microg litre(-1) indicated recent use of this herbicide, which has been banned since 1991, and was also the result of non-agricultural applications. Pathways for pesticide input to the receiving waters were related to both surface run-off and underground passage. Two-thirds of the observed diuron load in the surface water resulted from an input by run-off. This was expected as a result of total herbicide application targets to sealed surfaces infringing current regulations and recommendations. Diuron load varied between 0.6 and 1.2% of the estimated amount applied annually in the investigated catchments. Non-agricultural pesticide use contributed more than two-thirds of the whole observed pesticide load in the tributaries and at least one-third in the River Ruhr. 相似文献
67.
用地高辛标记核酸探针检测鹅细小病毒的研究 总被引:11,自引:2,他引:9
从带有鹅细小病毒(GPV)NSI基因的重组质粒pMD18T-NS1用限制性内切酶EcoRI和BamH1双酶切回收1880bp大小片段,并制备出地高辛标记的GPV核酸探针。其标记效率达到0.01pg/μl。特异性检测结果表明,该探针能与GPV不同毒株核酸发生特异性杂交,而与对照的DPV、GPPV等病毒的核酸杂交反应均为阴性;敏感性检测结果表明,该探针对GPV的最低检出量为0.0224pg。该探针对不同方法处理的GPV感染病料进行检测,均出现杂交阳性。表明所研制的标记探针用于GPV的检测足可行的。 相似文献
68.
Wilson DS Teagle DA Alt JC Banerjee NR Umino S Miyashita S Acton GD Anma R Barr SR Belghoul A Carlut J Christie DM Coggon RM Cooper KM Cordier C Crispini L Durand SR Einaudi F Galli L Gao Y Geldmacher J Gilbert LA Hayman NW Herrero-Bervera E Hirano N Holter S Ingle S Jiang S Kalberkamp U Kerneklian M Koepke J Laverne C Vasquez HL Maclennan J Morgan S Neo N Nichols HJ Park SH Reichow MK Sakuyama T Sano T Sandwell R Scheibner B Smith-Duque CE Swift SA Tartarotti P Tikku AA Tominaga M Veloso EA 《Science (New York, N.Y.)》2006,312(5776):1016-1020
Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D. 相似文献
69.
Liu PT Stenger S Li H Wenzel L Tan BH Krutzik SR Ochoa MT Schauber J Wu K Meinken C Kamen DL Wagner M Bals R Steinmeyer A Zügel U Gallo RL Eisenberg D Hewison M Hollis BW Adams JS Bloom BR Modlin RL 《Science (New York, N.Y.)》2006,311(5768):1770-1773
In innate immune responses, activation of Toll-like receptors (TLRs) triggers direct antimicrobial activity against intracellular bacteria, which in murine, but not human, monocytes and macrophages is mediated principally by nitric oxide. We report here that TLR activation of human macrophages up-regulated expression of the vitamin D receptor and the vitamin D-1-hydroxylase genes, leading to induction of the antimicrobial peptide cathelicidin and killing of intracellular Mycobacterium tuberculosis. We also observed that sera from African-American individuals, known to have increased susceptibility to tuberculosis, had low 25-hydroxyvitamin D and were inefficient in supporting cathelicidin messenger RNA induction. These data support a link between TLRs and vitamin D-mediated innate immunity and suggest that differences in ability of human populations to produce vitamin D may contribute to susceptibility to microbial infection. 相似文献
70.
Mora JR Iwata M Eksteen B Song SY Junt T Senman B Otipoby KL Yokota A Takeuchi H Ricciardi-Castagnoli P Rajewsky K Adams DH von Andrian UH 《Science (New York, N.Y.)》2006,314(5802):1157-1160
Normal intestinal mucosa contains abundant immunoglobulin A (IgA)-secreting cells, which are generated from B cells in gut-associated lymphoid tissues (GALT). We show that dendritic cells (DC) from GALT induce T cell-independent expression of IgA and gut-homing receptors on B cells. GALT-DC-derived retinoic acid (RA) alone conferred gut tropism but could not promote IgA secretion. However, RA potently synergized with GALT-DC-derived interleukin-6 (IL-6) or IL-5 to induce IgA secretion. Consequently, mice deficient in the RA precursor vitamin A lacked IgA-secreting cells in the small intestine. Thus, GALT-DC shape mucosal immunity by modulating B cell migration and effector activity through synergistically acting mediators. 相似文献