排序方式： 共有67条查询结果，搜索用时 531 毫秒
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Heil F Hemmi H Hochrein H Ampenberger F Kirschning C Akira S Lipford G Wagner H Bauer S 《Science (New York, N.Y.)》2004,303(5663):1526-1529
Double-stranded ribonucleic acid (dsRNA) serves as a danger signal associated with viral infection and leads to stimulation of innate immune cells. In contrast, the immunostimulatory potential of single-stranded RNA (ssRNA) is poorly understood and innate immune receptors for ssRNA are unknown. We report that guanosine (G)- and uridine (U)-rich ssRNA oligonucleotides derived from human immunodeficiency virus-1 (HIV-1) stimulate dendritic cells (DC) and macrophages to secrete interferon-alpha and proinflammatory, as well as regulatory, cytokines. By using Toll-like receptor (TLR)-deficient mice and genetic complementation, we show that murine TLR7 and human TLR8 mediate species-specific recognition of GU-rich ssRNA. These data suggest that ssRNA represents a physiological ligand for TLR7 and TLR8. 相似文献
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Jens Gebauer Annika Assem Elisabeth Busch Steffen Hardtmann Diana Möckel Franziska Krebs Tobias Ziegler Florian Wichern Martin Wiehle Katja Kehlenbeck 《Erwerbs-Obstbau》2014,56(1):9-24
In Germany and Europe exotic fruits from distant places are becoming more and more important. In the tropics and subtropics an enormous variety of edible fruits exists. In 2008 the dry fruit pulp of the baobab (Adansonia digitata L.) was approved as novel food for the EU and thus entered the formal food market. Hence, an increasing number of products became available in Europe. The baobab is an impressive tree in the savannas of Africa. Due to its dense and wide spreading root system and its enormous water storing capacity in the stem, the tree can grow under very dry environmental conditions. In many regions of Africa it is a multipurpose indigenous fruit tree species which offers shelter and provides food, fodder and medicine as well as raw material for many purposes. However, even in Europe a wide range of products is now available as shown in the present study, which identified more than 300 baobab products or products with baobab as an ingredient. In Germany, not only the natural baobab pulp but also ready-made foodstuffs such as soft drinks, sandwich spreads, cereal bars, sweets and chocolates are available. Furthermore, a diverse range of pharmaceutical and cosmetic products with extracts from the baobab is available in the market. The products range from after shave and perfume to shampoo and shower gel to leg lotion and foot spray. In Germany baobab saplings and seeds are offered for planting and cultivation as an indoor pot plant. Commercially marketed baobab bonsai seedlings for the European market are produced in Senegal. In Africa the baobab fruits are mainly harvested from wild stands. However, the commercial production of baobab fruits in orchards could be an important future opportunity for income generation to many local households. More research on baobab, including the domestication of this wild fruit tree species, and the conservation of its natural stands as important genetic resource are prerequisites for sustainably increased fruit production. 相似文献
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Daniela Blecker Nils Hiebert Franziska Kuhne 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(3):170-174
Revealing why pedestrians are afraid of some dogs while passing them in public is essential to assess the dog–owner–stranger relationship. Therefore, the effect of different dog features on passersby was gathered. Four dog features differing in size and color were investigated. The dog features were classified as small-dark, small-pale, large-dark, and large-pale. Dog's effect on passersby was recorded in 2 ways: (1) observing the behavioral responses of passersby while passing nearby a dog, and (2) revealing the passersby's perception of that dog by a short interview. Direct observations of 427 passersby's behavioral responses while passing a dog on a sideway were acquired, and 126 persons were interviewed. It was suggested that large-dark dogs seemed to be more threatening than pale or small dogs. Passersby confronted with pale dogs of equal size changed their way far less than when confronted with dark dogs. Significant differences were noted for the type of effect assessed and the reason for this behavioral response. The results showed that only the small-pale dog appeared to be friendly because of its size (P = 0.000). All other dogs were stated as friendly because of individual factors including breed and own dog experiences (P = 0.000). None of the dogs were mentioned as threatening. Our results show that some dog features have a significant effect on behavioral responses and the subjective perception of dogs by people in public. 相似文献
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Damian Tom-Dery Franziska Eller Christoph Reisdorff Kai Jensen 《Agroforestry Systems》2018,92(5):1353-1371
Shea (Vitellaria paradoxa C. F. Gaertn.) is arguably socio-economically and environmentally the most important plant species in the semi-arid and arid zones of Africa where it is widely distributed. Apart from the economic gains in international export markets where shea butter is valued for use in luxury cosmetic, pharmaceutical and confectionary industries, locally the fat (butter) is the main cooking oil for over 86 million inhabitants. Research during the past decades has acknowledged the chemical and nutritional composition as well as the ethnobotanical uses of shea which has resulted in its butter being used in a wide array of products. This review summarizes the current knowledge of the morphological and genetic diversity; propagation, initial growth, and management; ecology and population structure; chemical and nutritional composition as well as the socioeconomic and livelihood empowerment potential of shea. Little is known about the fruiting behaviour and the responses of shea to the inevitable changes in climate. We suggest ecophysiological and dendrochronological studies as an option to predict how the domestication of this multipurpose tree species can be sustained even under the prospects of global climate change. 相似文献
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Dominik Winckelmann Franziska Bleeke Peter Bergmann Clemens Elle Gerd Klöck 《International Aquatic Research》2016,8(1):81-90
The potential use of non-arable land in the al-Wusta region of the Sultanate of Oman for the production of algae biomass was examined. Brackish cleaned production water from oil production supplemented with commercial fertilizer was used as growth medium. The indigenous isolate Cyanobacterium aponinum WP7(1) was grown in open ponds using batch or semi-continuous cultivation. Biomass production rates of 15–24 g/m2/day were achieved. The change of salinity due to evaporation, which was thought to be a major challenge, did not exceed 35 ppt. All cultures showed contaminations with weed algae. Contaminations with green algae or diatoms were detectable using fluorescence pattern excited by four different wavelengths using a pulse-amplitude-modulation chlorophyll fluorometer (PAM). It is possible to estimate the health level and the mayor groups of which a culture is composed using the PAM method. Therefore, the fluorescence of the photosynthetically inactive sample is compared with the fluorescence after all copies of photosystem II were closed by exposing the sample to a high-intensity light beam. A detection limit of one weed algae cell in a hundred cells was achieved. 相似文献
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Marianne Richter Franziska Matheis Enik Gnczi Sbastien Aeby Bernhard Spiess Gilbert Greub 《Veterinary ophthalmology》2010,13(4):235-237
Corneal samples of cats with and without corneal diseases were screened with a pan‐Chlamydiales PCR and specific PCRs for Parachlamydia, Protochlamydia, Chlamydophila felis, Acanthamoeba and feline herpesviruses (FHV‐1). Several corneal samples tested positive for Parachlamydia and related Chlamydiales, indicating cat exposure to these intracellular bacteria. 相似文献
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Biochar application to temperate soils: Effects on soil fertility and crop growth under greenhouse conditions 总被引：3，自引：0，他引：3 
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下载免费PDF全文 Stefanie Kloss Franz Zehetner Bernhard Wimmer Jannis Buecker Franziska Rempt Gerhard Soja 《植物养料与土壤学杂志》2014,177(1):3-15
Biochar (BC) application as a soil amendment has aroused much interest and was found to considerably improve soil nutrient status and crop yields on poor, tropical soils. However, information on the effect of BC on temperate soils is still insufficient, with effects expected to differ from tropical soils. We investigated the effects of BC on soil nutrient dynamics, crop yield, and quality in a greenhouse pot experiment. We compared three agricultural soils (Planosol, Cambisol, Chernozem), and BCs of three different feedstocks (wheat straw [WS], mixed woodchips [WC], vineyard pruning [VP]) slowly pyrolyzed at 525°C, of which the latter was also pyrolyzed at 400°C. The BCs were applied at two rates (1% and 3%, which would correspond to 30 and 90 t ha–1 in the field). Three crops, namely mustard (Sinapis alba L.), barley (Hordeum vulgare L.), and red clover (Trifolium pretense L.) were grown successively within one year. The investigated soil properties included pH, electrical conductivity (EC), cation‐exchange capacity (CEC), calcium‐acetate‐lactate (CAL)–extractable P (PCAL) and K (KCAL), C, N, and nitrogen‐supplying potential (NSP). The results show a pH increase in all soils. The CEC increased only on the Planosol. The C : N ratio increased at 3% application rate. Despite improving the soil nutrient status partly, yields of the first crop (mustard) and to a lesser extent of the second crop (barley) were significantly depressed through BC application (by up to 68%); the yield of clover as third crop was not affected. Only the BC from WS maintained yields in the range of the control and even increased barley yield by 6%. The initial yield reduction was accompanied by notable decreases (Cu, Fe, Mn, Zn) and increases (Mo) in micronutrient concentrations of plant tissues while nitrogen concentrations were hardly affected. The results of the pot experiment show that despite additional mineral fertilization, short‐term growth inhibition may occur when applying BC without further treatment to temperate soils. 相似文献
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