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ObjectiveTo assess the sedative and immobilization effect of intranasal administration (INS) of midazolam (MID) without or with INS dexmedetomidine (DXM), and some physiological changes induced by the drugs. The ability of INS atipamezole to reverse the DXM component was also assessed.Study designProspective ‘blinded’ experimental study.AnimalsIn total, 15 pigeons.MethodsPigeons were sedated by INS MID alone at a dose of 5 mg kg−1 (group MID, n = 6) or in combination with INS DXM at a dose 80 μg kg−1 (group MID-DXM, n = 6). Measurements were made of heart rate (HR), respiratory rate (fR) and cloacal temperature (CT). The degree of sedation was assessed at 15 minutes prior to, immediately after, and at intervals until 100 minutes after drug administrations. Following MID-DXM, INS atipamezole (250 μg kg−1) was administered and the same indices measured 5 and 10 minutes later.ResultsMID had no effect on HR and fR, and although CT decreased, it remained within physiological range. MID-DXM caused significant falls in HR, fR and CT that persisted until the end of sedation. Atipamezole antagonized sedation and cardiorespiratory side effects of MID-DXM within 10 minutes of application. In addition, for MID compared to MID-DXM, the lowest sedation scores [10 (7–14) and 10.5 (5–14) versus 2 (1–4) and 2 (1–5)] were achieved in the 10th and 20th minute versus the 20th and 30th minute of the sedation, respectively.Conclusions and clinical relevanceMID alone, given INS had minimal side effects on vital functions but caused inadequate immobilization of pigeons for restraint in dorsal recumbency. MID-DXM caused an effective degree of immobilization from 20 to 30 minutes after administration, at which time birds tolerated postural changes without resistance. Atipamezole antagonized both side effects and sedation, but complete recovery had not occurred within 10 minutes after its application.  相似文献   
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Cost estimation is probably the most decisive factor in the process of computer-aided, preliminary planning for low-volume road networks. However, the cost of construction is normally assumed to be route-independent for a specific project area, resulting in sub-optimal layouts. This is especially true for mountainous terrain and in areas with unstable subsoil. Here, we present a model for more accurately estimating spatial variability in road life-cycle costs, based on terrain surface properties as well as geological properties of the subsoil. This parametric model incorporates four structural components: embankment, retaining structures, pavement, and drainage and stream-crossing structures. It is linked to a geo-database that allows users to derive location-specific parameter values as input. In applying this model, we have demonstrated that variability in costs ranges widely for mountainous areas, with the most expensive construction being approximately five times greater there than on more favorable sites. This variability strongly affects the optimal layout of a road network. First, when location-specific slope gradients are considered, costs are reduced by about 17% from those calculated via currently available engineering practices; when both slope gradient and geotechnical formations are included, those costs are decreased by about 20%. Second, the length of the road network is increased by about 4% and 10% respectively, compared with current practices.  相似文献   
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Processed aconite drugs are widely used in Eastern medicine as painkillers and antirheumatic agents. It is known that the traditional processing of aconite drugs increases the amount of lipo-alkaloids. In order to obtain information about the pharmacological potential of these compounds, semisynthesis of 9 aconitine-derived lipo-alkaloids was carried out and their COX-1, COX-2 and LTB4 formation inhibitory activities were investigated. It was found that compounds esterified with unsaturated fatty acids demonstrated significant COX-2 inhibitory effects, while in the COX-1 assay only 14-benzoylaconine-8-O-eicosapentaenoate exerted remarkable activity. The inhibition of LTB4 formation was pronounced in cases of long chain fatty acid derivatives.  相似文献   
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ABSTRACT

Winter wheat in northwestern Europe is often fertilized with several doses of calcium-ammonium-nitrate (CAN). For economy, farmers fertilize using a combination of N-doses. Here, we examined the necessity of N splitting (1–3) and application timing in experiments conducted in 2010 using a one-factorial fully randomized block design, and in 2011–2012 using a two-factorial split-plot design (four replicates). The study site, in southwestern Germany, had silty loam soil, and modern cultivars (2010: one cultivar, 2011–2012: three cultivars) with different genetic abilities to develop the yield components of interest were tested. A late first or single N application at stage BBCH 29/31 did not lead to differences in grain yields or protein contents compared to three N applications. However, a single N application at stage BBCH 25/27 resulted in a reduced protein content. Yield component development did not significantly differ among the cultivars. Early N application increased plant density but not yield. In two years, low plant densities were compensated by higher numbers of kernels per spike. Hence, under the tested conditions, the number of N applications could be reduced, as the high compensation ability of modern cultivars allows N fertilization consisting of two or even one application.  相似文献   
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Zusammenfassung Die Kulturpflanzenevolution im alpinen Raum ist durch drei Faktoren geprägt, durch klimatische, geologisch-landschaftsmorphologische und geschichtliche. Die Aufgliederung in cine Vielzahl von ökologischen Nischen, in denen verdrängte Arten und Varietäten überleben konnten, mußte zwangsläufig zu einer bestimmten Formenanreicherung führen. Ihr stcht aber ein scharfer natürlicher Selektionsdruck einschränkend entgegen, der mit fortschreitender Höhenlage stärker wird. Er bestimmt letztlich das Ausschen der Populationen und läßt allfällige Zufallsfaktoren bei beginnender Einnischung und kleiner werdenden Populationsgrößen in den Hintergrund treten. Darin liegt die Ursache, daß mit zunehmender Höhenlage die Populationen uniformer werden, die umgekehrt im Flachland die größte Variabilität aufweisen.Die Kulturpflanzenarten, Varietäten und Sorten sind einem ständigen Bewegungsprozeß unterworfen, bedingt durch das Streben des Menschen, Leistung, Qualität, Aussehen, usw., zu verbessern. Die Suche nach Neuem birgt stets die Möglichkeit in sich, daß ein besseres Sortiment das altbewährte verdrängt. Ist eine Sorte ausreichend adaptierfähig und bringt sie eine Verbesserung mit sich, wird sie sich schrittweise — das alte Sortiment vor sich herschiebend — bis in die Alpentäler ausbreiten. Die Frage, wieviele Arten und Varietäten auf diese Weise ins Land gelangten, bleibt unbeantwortet. Jedenfalls waren es nur wenige, die diesem Verdrängungsprozeß haben standhalten können und bis heute erhalten geblieben sind.Wenn wir im Rückzugsgebiet der Alpen eine Formenanhäufung finden, die historisch betrachtet einen Abriß des Widerstandsfähigsten aus den letzten Jahrhunderten darstellt, ist dieser Formenreichtum doch bescheiden im Vergleich zu dem eines Genzentrums. Besteht hier das entscheidende evolutionsmotorische Moment darin, daß neu entstandene Formen auch eine entsprechende Überlebens-und Fortpflanzungschance besitzen, wirkt der scharfe Selektionsdruck der Alpen einer solchen Mannigfaltigkeit entgegen und wird stets in genotypische wie phänotypische Uniformität münden.
Crop genetic ressources in the alps
Summary The evolution of cultivated plants in the area of the Alps is especially influenced by climatical, geological-orographical and historical factors. The available abundance of ecological niches providing chances for the survival of otherwise displaced species and varieties, consequently led to a certain increase of diversity. It is counteracted by strong natural selection pressures increasing with progressive altitudes. These selection pressures ultimately determine the composition of the populations and predominate over coincidental factors during the first phases of annidation connected with descreasing population size. That causes an increasing uniformity of the populations in higher altitudes whereas in the lowlands the highest diversity can be found.Due to human efforts in improving yields, quality, appearance, etc., of cultivated species, varieties and cultivars, they are subject to a permanent evolutionary process. The search for new material always includes the possibility that better accessions displace the well-known old ones. If a variety is sufficiently adaptable and shows improved characters, it will proceed step by step, — pushing the old accessions ahead of it — into the valleys of the Alps. How many species and varieties were introduced in this way is a question which cannot be answered. Anyway, only a few varieties could resist this displacing process and are in existance still today.Though we can find a certain amount of variation in the refugial area of the Alps, which, as seen from the historical standpoint of view, represents a part of the most resistant races from the last few centuries, this variation is relatively low in comparison with that of a gene center. In a gene center the decisive evolutionary mechanisms result in the maintaining of newly evolved forms whereas the strong selection pressures of the Alps counteract a high variability and will always lead to genotypical and phenotypical uniformity.

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The molecular basis by which human breast milk supports the development of a protective intestinal microbiome in infants is unknown. After lactose and lipids, human milk oligosaccharides (HMOs) are quantitatively the third largest and most diverse component of breast milk. In this work, glycomic profiling of HMO consumption by bifidobacteria using Fourier transform ion cyclotron resonance mass spectrometry reveals that one species, Bifidobacterium longum biovar infantis ATCC 15697, an isolate from the infant gut, preferentially consumes small mass oligosaccharides, representing 63.9% of the total HMOs available. These HMOs were detected in human breast milk at the onset and constantly through the first month of lactation by use of high performance liquid chromatography-chip time-of-flight mass spectrometry. Further characterization revealed that strain ATCC 15697 possesses both fucosidase and sialidase activities not present in the other tested strains. This work provides evidence that these small mass HMOs are selectively metabolized by select bifidobacterial strains and represent a potential new class of bioactive molecules functioning as prebiotics to facilitate a protective gut colonization in breast-fed newborns.  相似文献   
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