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'Molecular farming' is the production of valuable recombinant proteins in transgenic organisms on an agricultural scale. While plants have long been used as a source of medicinal compounds, molecular farming represents a novel source of molecular medicines, such as plasma proteins, enzymes, growth factors, vaccines and recombinant antibodies, whose medical benefits are understood at a molecular level. Until recently, the broad use of molecular medicines was limited because of the difficulty in producing these proteins outside animals or animal cell culture. The application of molecular biology and plant biotechnology in the 1990s showed that many molecular medicines or vaccines could be synthesised in plants and this technology is termed 'molecular farming'. It results in pharmaceuticals that are safer, easier to produce and less expensive than those produced in animals or microbial culture. An advantage of molecular farming lies in the ability to perform protein production on a massive scale using hectares of cultivated plants. These plants can then be harvested and transported using the agricultural infrastructure. Thus, molecular farming allows rapid progress from genetic engineering to crop production, and new cash crops producing recombinant proteins are already being commercially exploited. We speculate that as functional genomics teaches us more about the nature of disease, molecular farming will produce many of the protein therapeutics that can remedy it.  相似文献   
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When studying species for phytoremediation of petroleum-contaminated soils, one of the main traits is the root zone where enhanced petroleum degradation takes place. Root morphological characteristics of three tropical graminoids were studied. Specific root length (SRL), surface area, volume and average root diameter (ARD) of plants grown in crude oil-contaminated and uncontaminated soil were compared. Brachiaria brizantha and Cyperus aggregatus showed coarser roots in polluted soil compared to the control as expressed in an increased ARD. B. brizantha had a significantly larger specific root surface area in contaminated soil. Additionally, a shift of SRL and surface area per diameter class towards higher diameters was found. Oil contamination also caused a significantly smaller SRL and surface area in the finest diameter class of C. aggregatus. The root structure of Eleusine indica was not significantly affected by crude oil. Higher specific root surface area was related to higher degradation of petroleum hydrocarbons found in previous studies.  相似文献   
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Sediment, sediment trap, Mytilus, Macoma and flounder samples from Northern Baltic (Finnish archipelago) have been analyzed for their contents of aliphatic and aromatic hydrocarbons. Androstane and hexaethylbenzene were used as internal standards. The analysis procedure consisted of alkaline degradation of fat, column fractionation of the two residue groups and final determination by glass capillary gas chromatography with FID for aliphatic hydrocarbon group and with mass spectrometry for non-polar aromatic residue group. The latter group was also determined by high pressure liquid chromatography. The residues due to oil pollution were distinguished from compounds of pure natural origin on the basis of statistical treatment of the determination results.  相似文献   
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Zusammenfassung  2-Chlorvinylarsindichlorid (Lewisit I) und 2,2′-Dichlordivinylarsinchlorid (Lewisit II) reagieren bei Raumtemperatur in einer Substitutionsreaktion schnell und quantitativ mit Dithiolen. Die Derivate wurden massenspetrometrisch identifiziert. Sie sind mit GC/ECD detektierbar. Diese Reaktionen k?nnen zur gaschromatographischen Bestimmung von Lewisiten in Wasser-und Bodenproben eingesetzt werden.   相似文献   
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Die ?kotoxikologie mu? sich mit biologischen Systemen und ihren Antworten auf schadstoffinduzierten Stre? auseinandersetzen. Die hierzu verwendete experimentelle Technik eilt dabei den M?glichkeiten dynamischer, proze?orientierter mathematischer Modellierung weit voraus. In dieser methodisch orientierten Arbeit werden Techniken aus der mathematischen Disziplin der Verbandstheorie vorgestellt, die eine Datenanalyse unter den Aspekten vergleichender Bewertung erlauben. Wichtige Ergebnisse sind dabei
–  • Aussagen zur Diversit?t mikrobieller Systeme (soweit durch die hier verwendeten Muster von vier Phospholipidfetts?uren erfa?bar),
–  • Analysen ordinaler Abh?ngigkeiten sowie
–  • komprimierte Darstellung komplexer Befunde im Zusammenhang mit der Toxizit?t von Huminstoff-Chemikalien-Systemen.
  相似文献   
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Wood samples impregnated with inorganic wood preservatives containing the elements arsenic, boron, chromium, copper, fluorine, and/or zinc were burned in a furnace. Three different kinds of ash were collected: furnace, boiler, and so-called fly ash. Analyses showed that the ash contained large amounts of elements originating from the inorganic wood preservatives. Further interest was focused on the leachability of the above-mentioned elements. For this purpose a laboratory batch leaching test according to the German Standard DIN 38 414 part 4 was chosen. The results indicate that the leachability is in a range where the release of these elements to the environment from deposited ash can be considered as detrimental.  相似文献   
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