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51.
Deficiency of PORCN, a regulator of Wnt signaling, is associated with focal dermal hypoplasia 总被引:1,自引:0,他引:1
Grzeschik KH Bornholdt D Oeffner F König A del Carmen Boente M Enders H Fritz B Hertl M Grasshoff U Höfling K Oji V Paradisi M Schuchardt C Szalai Z Tadini G Traupe H Happle R 《Nature genetics》2007,39(7):833-835
Focal dermal hypoplasia (FDH) is an X-linked dominant multisystem birth defect affecting tissues of ectodermal and mesodermal origin. Using a stepwise approach of (i) genetic mapping of FDH, (ii) high-resolution comparative genome hybridization to seek deletions in candidate chromosome areas and (iii) point mutation analysis in candidate genes, we identified PORCN, encoding a putative O-acyltransferase and potentially crucial for cellular export of Wnt signaling proteins, as the gene mutated in FDH. The findings implicate FDH as a developmental disorder caused by a deficiency in PORCN. 相似文献
52.
Julie K. Westphal Max J. Dörfel Susanne M. Krug Jimmi D. Cording Jörg Piontek Ingolf E. Blasig Rudolf Tauber Michael Fromm Otmar Huber 《Cellular and molecular life sciences : CMLS》2010,67(12):2057-2068
Sealing of the paracellular cleft by tight junctions is of central importance for epithelia and endothelia to function as
efficient barriers between the extracellular space and the inner milieu. Occludin and claudins represent the major tight junction
components involved in establishing this barrier function. A special situation emerges at sites where three cells join together.
Tricellulin, a recently identified tetraspan protein concentrated at tricellular contacts, was reported to organize tricellular
as well as bicellular tight junctions. Here we show that in MDCK cells, the tricellulin C-terminus is important for the basolateral
translocation of tricellulin, whereas the N-terminal domain appears to be involved in directing tricellulin to tricellular
contacts. In this respect, identification of homomeric tricellulin-tricellulin and of heteromeric tricellulin-occludin complexes
extends a previously published model and suggests that tricellulin and occludin are transported together to the edges of elongating
bicellular junctions and get separated when tricellular contacts are formed. 相似文献
53.
Noteworthy records of reptiles from the state of Jalisco, Mexico, are presented. The first state records of Coleonyx elegans nemoralis, the second state record for Geophis tarascae, and notes on the distribution and reproduction of Eumeces brevirostris indubitus are discussed. 相似文献
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Christina Ulm Mona Saffarzadeh Poornima Mahavadi Sandra Müller Gerlinde Prem Farhan Saboor Peter Simon Ralf Middendorff Hildegard Geyer Ingrid Henneke Nils Bayer Susanne Rinné Thomas Lütteke Eva Böttcher-Friebertshäuser Rita Gerardy-Schahn David Schwarzer Martina Mühlenhoff Klaus T. Preissner Andreas Günther Rudolf Geyer Sebastian P. Galuska 《Cellular and molecular life sciences : CMLS》2013,70(19):3695-3708
Posttranslational modification of the neural cell adhesion molecule (NCAM) by polysialic acid (polySia) is well studied in the nervous system and described as a dynamic modulator of plastic processes like precursor cell migration, axon fasciculation, and synaptic plasticity. Here, we describe a novel function of polysialylated NCAM (polySia-NCAM) in innate immunity of the lung. In mature lung tissue of healthy donors, polySia was exclusively attached to the transmembrane isoform NCAM-140 and located to intracellular compartments of epithelial cells. In patients with chronic obstructive pulmonary disease, however, increased polySia levels and processing of the NCAM carrier were observed. Processing of polysialylated NCAM was reproduced in a mouse model by bleomycin administration leading to an activation of the inflammasome and secretion of interleukin (IL)-1β. As shown in a cell culture model, polySia-NCAM-140 was kept in the late trans-Golgi apparatus of lung epithelial cells and stimulation by IL-1β or lipopolysaccharide induced metalloprotease-mediated ectodomain shedding, resulting in the secretion of soluble polySia-NCAM. Interestingly, polySia chains of secreted NCAM neutralized the cytotoxic activity of extracellular histones as well as DNA/histone-network-containing “neutrophil extracellular traps”, which are formed during invasion of microorganisms. Thus, shedding of polySia-NCAM by lung epithelial cells may provide a host-protective mechanism to reduce tissue damage during inflammatory processes. 相似文献
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Rudolf Lewandowski 《Journal of forecasting》1982,1(2):205-214
This paper describes a sales forecasting system widely used by European companies. The system, known as FORSYS, includes several unique characteristics which increase its use and applicability among practitioners. FORSYS is simple to use; its underlying rationale is clear to the user; it is adaptive, and it allows the incorporation of special events into the model in order to determine their influence on forecasting. 相似文献
59.
Novel microbial communities of the Haakon Mosby mud volcano and their role as a methane sink 总被引:5,自引:0,他引:5
Niemann H Lösekann T de Beer D Elvert M Nadalig T Knittel K Amann R Sauter EJ Schlüter M Klages M Foucher JP Boetius A 《Nature》2006,443(7113):854-858
Mud volcanism is an important natural source of the greenhouse gas methane to the hydrosphere and atmosphere. Recent investigations show that the number of active submarine mud volcanoes might be much higher than anticipated (for example, see refs 3-5), and that gas emitted from deep-sea seeps might reach the upper mixed ocean. Unfortunately, global methane emission from active submarine mud volcanoes cannot be quantified because their number and gas release are unknown. It is also unclear how efficiently methane-oxidizing microorganisms remove methane. Here we investigate the methane-emitting Haakon Mosby Mud Volcano (HMMV, Barents Sea, 72 degrees N, 14 degrees 44' E; 1,250 m water depth) to provide quantitative estimates of the in situ composition, distribution and activity of methanotrophs in relation to gas emission. The HMMV hosts three key communities: aerobic methanotrophic bacteria (Methylococcales), anaerobic methanotrophic archaea (ANME-2) thriving below siboglinid tubeworms, and a previously undescribed clade of archaea (ANME-3) associated with bacterial mats. We found that the upward flow of sulphate- and oxygen-free mud volcano fluids restricts the availability of these electron acceptors for methane oxidation, and hence the habitat range of methanotrophs. This mechanism limits the capacity of the microbial methane filter at active marine mud volcanoes to <40% of the total flux. 相似文献
60.
Biogeochemistry: methane and microbes 总被引:1,自引:0,他引:1