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991.
Klaus Urbahns Michael H?rter Markus Albers Delf Schmidt Beatrix Stelte-Ludwig Ulf Brüggemeier Andrea Vaupel Christoph Gerdes 《Bioorganic & medicinal chemistry letters》2002,12(2):205-208
Vitronectin receptor (alpha(V)beta(3)) antagonism has been implicated as a mechanism for the treatment of restenosis following balloon angioplasty. In this work we present results from screening of a focused combinatorial library based on a biphenyl moiety. Our SAR studies led to the identification of compounds with subnanomolar activity, selectivity towards the related GPIIbIIIa receptor and functional activity on human smooth muscle cell migration. 相似文献
992.
HISTORICAL BIOGEOGRAPHY OF THE HOLARCTIC: AREA RELATIONSHIPS, ANCESTRAL AREAS, AND DISPERSAL OF NON-MARINE ANIMALS 总被引:1,自引:0,他引:1
Henrik Enghoff 《Cladistics : the international journal of the Willi Hennig Society》1995,11(3):223-263
Abstract — Based on published phylogenies for 73 groups of Holarctic non-marine animals, interrelationships between the four Holarctic infraregions (western and eastern Nearctic, western and eastern Palearctic) are examined. The study includes analysis of resolved area cladograms, ancestral areas and dispersal indicated by cladistic subordinateness. Area relationships reflecting present continental configurations (Nearctic vs. Palearctic) dominate the material to the extent that one might speak of a general Holarctic area pattern. Paleocontinental (western Nearctic+eastern Palearctic, western Palearctic+eastern Nearctic) and disjunct patterns are relatively more frequent among groups of higher taxonomic rank. The western Nearctic seems to have played a bigger role than the other infraregions as a center of origin. Two computer programs for constructing resolved area cladograms, viz., COMPONENT 1.5 and COMPONENT 2.0, are compared. The three standard assumptions for biogeographical analysis are compared and arguments are presented in favour of Assumption 0. 相似文献
993.
994.
Henrik Balslev 《The Botanical review》2011,77(4):370-380
Tropical forests harbor thousands of useful plants that are harvested and used in subsistence economies or traded in local,
regional or international markets. The effect on the ecosystem is little known, and the forests resilience is badly understood.
Palms are the most useful group of plants in tropical American forests. This paper introduces a cross-disciplinary study of
the effects of harvesting palm products from the tropical forests in north-western South America. The size of the resource
is estimated through palm community studies in the different forest formations that determines the number of species and individuals
of all palm species. The genetic structure of useful palm species is studied to determine how much harvesting of the species
contributes to genetic erosion of its populations, and whether extraction can be made without harm. Almost all palm species
are used in rural communities for subsistence purposes Quantitative ethno-botanical research in different forest types have
identified thousands of different ways of using palms for food, construction, tool-making, etc. Although most palms are used
by the person harvesting them, many are sold on local markets as fruits, fiber, tools, construction materials etc., and a
few have reached larger markets, including international markets. Palm populations are managed in various ways of which some
are sustainable and others are destructive. National level mechanisms that governs extraction, trade and commercialization
of palm products, are used to identify positive and negative policies in relation to resilience of ecosystems. 相似文献
995.
Structural analysis of the reducing side of photosystem I (PSI) has been carried out using chemical cross-linking and monospecific antibodies. Incubation of PSI isolated from barley (Hordeum vulgare L.) with the hydrophilic cross-linking agent N-ethyl-3-[3-(dimethylamino) propyl]-carbodiimide leads to cross-linking of the PSI-D subunit with the PSI-E and PSI-H subunits. In the presence of ferredoxin, cross-linking results in the formation of cross-linked products composed of PSI-D, PSI-E and ferredoxin and in a block in steady state NADP+ photoreduction. No cross-linking of ferredoxin occurs at elevated ionic strength or using heat-denatured ferredoxin. Cross-linking of ferredoxin does not inhibit electron transfer from plastocyanin to methyl viologen. Steady state NADP+ photoreduction was analyzed in PSI or thyla-koids incubated with antibodies against individual PSI subunits. Incubation with antibodies against PSI-C, -H, -I, or -L had no effect on PSI activity, whereas antibodies against PSI-D or PSI-E had similar effects and caused a large decrease in activity. The results provide evidence that the PSI-D and PSI-E subunits are localized on the reducing side of PSI, forming a barrier between PSI-C and the stroma as well as a docking site for ferredoxin. The PSI-H subunit has an exposed, stromal domain but this does not appear to contribute to the ferredoxin docking. 相似文献
996.
997.
HCO3? is shown to be a noncompetitive inhibitor of glycollate oxidase from parsley leaves with respect ot glycolic acid. The Ki is found to be 20 mM at pH 7,7. 相似文献
998.
999.
Nicole Brösicke Frank K. H. van Landeghem Björn Scheffler Andreas Faissner 《Cell and tissue research》2013,354(2):409-430
The extracellular matrix (ECM) protein tenascin-C (TN-C) is upregulated within glioma tissues and cultured glioma cell lines. TN-C possesses a multi-modular structure and a variety of functional properties have been reported for its domains. We describe five novel monoclonal antibodies identifying different domains of TN-C. The epitopes for these antibodies were investigated by using recombinantly expressed fibronectin type III domains of TN-C. The biological effects of TN-C fragments on glioma cell proliferation and adhesion were analyzed. The expression pattern of TN-C in human glioma tissue sections and in glioma cell lines was studied with the novel library of monoclonal antibodies. The immunocytochemical analyses of the established human glioma cell lines U-251-MG, U-373-MG and U-87-MG revealed distinct staining patterns for each antibody. Robust expression of TN-C was found within the tumor mass of surgery specimens from glioblastoma. In many cases, the expression of this ECM molecule was clearly associated with blood vessels, particularly with microvessels. Three of the new antibodies highlighted individual TN-C-expressing single cells in glioma tissues. The effect of TN-C domains on glioma cells was examined by a BrdU-proliferation assay and an adhesion assay. Short fragments of constitutively expressed TN-C-domains did not exert significant effects on the proliferation of glioma cells, whereas the intact molecule increased cell division rates. In contrast, the long fragment TNfnALL containing all of the FNIII domains of TN-C decreased proliferation. Additionally, we found strong differences between the adhesion-influencing properties of the recombinant fragments on glioma cells. 相似文献
1000.
The internet constitutes a popular source of health information. However, the use of the internet and other modern media in the domain of mental health remains widely unclear. This study aimed at exploring the readiness for seeking information online and making use of online counseling and media-assisted psychotherapy. A representative survey of N = 2411 Germans was conducted. Results indicated that more than one fourth of Germans would consider seeking help online in case of psychic strain. Participants reported that they would use the internet when needing to research about mental health topics and to communicate with persons concerned on internet forums. Only a small number of participants had already used psychological online-counseling. The majority of subjects reported not having known about the possibility of online counseling. However, the willingness to make use of this option in the future was in a medium range. Concerning the treatment of mental disorders, participants showed a clear preference toward conventional face-to-face treatment. Less than 10% of participants considered the use of treatment supported by mobile phones, the internet, or virtual realities as likely. Certainly, readiness was significantly higher in persons who were already using the relevant devices—mobile phones, computers, and the internet. In the future, there will presumably be an increasing demand for media-assisted psychological counseling and interventions. Members of the health care system should therefore prepare for current developments and help enlighten patients with regard to the possibilities, and also the potential risks of e-mental health. 相似文献