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排序方式: 共有475条查询结果,搜索用时 343 毫秒
291.
Chlodwig Franz Heinrich Glasl 《Plant foods for human nutrition (Dordrecht, Netherlands)》1974,24(1-2):175-182
Parsley varieties may be characterized by the composition of essential oils in leaves. There are the same differentiations in content of myristicin and apiole as found in fruit oils. Methods of thin-layer- and gas-liquid chromatography for objective estimation of quality of parsley leaves are described. 相似文献
292.
Halberg F Cornélissen G Katinas G Syutkina EV Sothern RB Zaslavskaya R Halberg F Watanabe Y Schwartzkopff O Otsuka K Tarquini R Frederico P Siggelova J 《Journal of circadian rhythms》2003,1(1):2-61
Afew puzzles relating to a small fraction of my endeavors in the 1950s are summarized herein, with answers to a few questions of the Editor-in-Chief, to suggest that the rules of variability in time complement the rules of genetics as a biological variability in space. I advocate to replace truisms such as a relative constancy or homeostasis, that have served bioscience very well for very long. They were never intended, however, to lower a curtain of ignorance over everyday physiology. In raising these curtains, we unveil a range of dynamics, resolvable in the data collection and as-one-goes analysis by computers built into smaller and smaller devices, for a continued self-surveillance of the normal and for an individualized detection of the abnormal. The current medical art based on spotchecks interpreted by reference to a time-unqualified normal range can become a science of time series with tests relating to the individual in inferential statistical terms. This is already doable for the case of blood pressure, but eventually should become possible for many other variables interpreted today only based on the quicksand of clinical trials on groups. These ignore individual differences and hence the individual's needs. Chronomics (mapping time structures) with the major aim of quantifying normalcy by dynamic reference values for detecting earliest risk elevation, also yields the dividend of allowing molecular biology to focus on the normal as well as on the grossly abnormal. 相似文献
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295.
Herrmann DC Maksimov A Pantchev N Vrhovec MG Conraths FJ Schares G 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(11-12):497-502
The cat is the definitive host of Toxoplasma gondii and plays an important role in the transmission of this and other coccidian parasites, e.g. Hammondia hammondi, a protozoon closely related and morphologically similar to T. gondii. A number of techniques to detect T. gondii nucleic acids in feline faeces are described and several extraction kits for isolating pathogen DNA from faeces or soil are commercially available. To compare the performance of such kits with regard to isolating oocyst DNA, a feline sample that had tested negative for coccidian parasites including T. gondii and H. hammondi was spiked with 10(4), 10(3), 10(2), 50 and 10 H. hammondi oocysts. Several ready-to-use stool or soil kits and an in-house method were then used to extract parasite DNA from these spiked faecal samples. Of six kits tested, two were found suitable for the detection of H. hammondi oocysts DNA by the polymerase chain reaction (PCR) in faecal samples with a detection limit of 250 oocysts per 1 g of faecal sample. These two kits revealed a similar, even slightly lower detection limit (50 oocysts per 1 g of sample) when tested with faecal samples spiked with T gondii oocysts. 相似文献
296.
Iglseder A Franz S Benetka V Möstl K Latif M Walk K Baumgartner W 《Schweizer Archiv für Tierheilkunde》2011,153(10):441-447
Enzootic bronchopneumonia (EBP) is an infectious, multifactorial respiratory disease of cattle. Different viruses may be involved in its pathogenesis. In this study an adapted method of endoscopic bronchoalveolar lavage (BAL) of caudal parts of the right cranial lung lobe was established and evaluated. The obtained bronchoalveolar lavage fluid (BALF) served as template for the detection of BRSV, BPIV-3 and BCoV specific nucleic acids by RT-PCR. BALF samples of 44 cattle affected with respiratory disease were compared to nasal swabs in their reliability to detect the causative agent(s). In 6/7 animals tested positive for BRSV, RNA of this virus was detected in the BALF, in 4 animals it could be found in the nasal swabs. In two of the three BPIV-3 positive animals, the BALF was the only material that tested positive. The most reliable samples for detection of 15 BCoV positive animals were the nasal swabs. BAL was easy to perform, it led to severe coughing in one case and moderate worsening of dyspnoe in three cases. In conclusion this study shows that BAL of the right cranial lung lobe is in many cases the only tool to detect BRSV and BPIV-3, major viral triggers of EBP. 相似文献
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298.
Soil nitrite as a source of atmospheric HONO and OH radicals 总被引:4,自引:0,他引:4
Su H Cheng Y Oswald R Behrendt T Trebs I Meixner FX Andreae MO Cheng P Zhang Y Pöschl U 《Science (New York, N.Y.)》2011,333(6049):1616-1618
Hydroxyl radicals (OH) are a key species in atmospheric photochemistry. In the lower atmosphere, up to ~30% of the primary OH radical production is attributed to the photolysis of nitrous acid (HONO), and field observations suggest a large missing source of HONO. We show that soil nitrite can release HONO and explain the reported strength and diurnal variation of the missing source. Fertilized soils with low pH appear to be particularly strong sources of HONO and OH. Thus, agricultural activities and land-use changes may strongly influence the oxidizing capacity of the atmosphere. Because of the widespread occurrence of nitrite-producing microbes, the release of HONO from soil may also be important in natural environments, including forests and boreal regions. 相似文献
299.
Perry L Dickau R Zarrillo S Holst I Pearsall DM Piperno DR Berman MJ Cooke RG Rademaker K Ranere AJ Raymond JS Sandweiss DH Scaramelli F Tarble K Zeidler JA 《Science (New York, N.Y.)》2007,315(5814):986-988
Chili peppers (Capsicum spp.) are widely cultivated food plants that arose in the Americas and are now incorporated into cuisines worldwide. Here, we report a genus-specific starch morphotype that provides a means to identify chili peppers from archaeological contexts and trace both their domestication and dispersal. These starch microfossils have been found at seven sites dating from 6000 years before present to European contact and ranging from the Bahamas to southern Peru. The starch grain assemblages demonstrate that maize and chilies occurred together as an ancient and widespread Neotropical plant food complex that predates pottery in some regions. 相似文献
300.
Büntgen U Tegel W Nicolussi K McCormick M Frank D Trouet V Kaplan JO Herzig F Heussner KU Wanner H Luterbacher J Esper J 《Science (New York, N.Y.)》2011,331(6017):578-582
Climate variations influenced the agricultural productivity, health risk, and conflict level of preindustrial societies. Discrimination between environmental and anthropogenic impacts on past civilizations, however, remains difficult because of the paucity of high-resolution paleoclimatic evidence. We present tree ring-based reconstructions of central European summer precipitation and temperature variability over the past 2500 years. Recent warming is unprecedented, but modern hydroclimatic variations may have at times been exceeded in magnitude and duration. Wet and warm summers occurred during periods of Roman and medieval prosperity. Increased climate variability from ~250 to 600 C.E. coincided with the demise of the western Roman Empire and the turmoil of the Migration Period. Such historical data may provide a basis for counteracting the recent political and fiscal reluctance to mitigate projected climate change. 相似文献