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1.
The ability of a number of nitrogen-containing compounds that simultaneously carry the adamantane and monoterpene moieties to inhibit Tdp1, an important enzyme of the DNA repair system, is studied. Inhibition of this enzyme has the potential to overcome chemotherapeutic resistance of some tumor types. Compound (+)-3c synthesized from 1-aminoadamantane and (+)-myrtenal, and compound 4a produced from 2-aminoadamantane and citronellal were found to be most potent as they inhibited Tdp1 with IC50 values of 6 and 3.5 µM, respectively. These compounds proved to have low cytotoxicity in colon HCT-116 and lung A-549 human tumor cell lines (CC50 > 50 µM). It was demonstrated that compound 4a at 10 µM enhanced cytotoxicity of topotecan, a topoisomerase 1 poison in clinical use, against HCT-116 more than fivefold and to a lesser extent of 1.5 increase in potency for A-549.  相似文献   
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In this paper, I read Leïla Sebbar’s staging in her novel Shérazade: 17 ans, brune, frisée, les yeux verts of the resistance by children of North African and other immigrants in the early 1980s to the French state’s cartographic modes and documents of control. The paper will consider the many uses to which the map was put by the French state in its colonization of North Africa and particularly Algeria, and later in its attempts to control the banlieues its policies of citizenship and cartographic control yielded on the margins of Paris. In this context, I will explore the ways in which the novel’s characters, living clandestinely in a squatt, simultaneously resist, put to use, and even supercede state documents of control as they disrupt everyday life and conduct heists across the city of Paris. The paper will explore unofficial cartographies of Paris, from those afforded by the radios libres and alternative publications such as Libération and Sans Frontièrez, to oral and almost proverbial networks of knowledge criss-crossing the city of Paris, while also tracing the uses to which supplemental cartographic sketches and counterfeit identity cards are put in the pages of the novel. The paper will be in dialogue with theoretical and critical formulations of space, cartography, and state control put forward by Michel de Certeau, Henri Lefebvre, Michel Foucault, and Tom Conley. The paper will conclude with a consideration of the means and limits of resistance by the novel’s characters in the context of this body of theory and criticism.  相似文献   
4.
Over 80% of the values of approximate digestibility (AD), efficiency of conversion of assimilated food to biomass (ECD) and efficiency of conversion of ingested food (ECI) calculated using energy terms are greater than the corresponding dry weight (DW) values, based on data for over 65 species (38 studies; number of comparative values: AD=139, ECD=128 and ECI=169). Largest positive differences (energy > DW values) are 30 (AD, ECD) and 24 (ECI) percentage points and largest negative differences (energy < DW values) are 9 (AD), 11 (ECD) and 8 (ECI) percentage points. These differences generally are least for ECI (71% of the differences fall between 0 and +5 percentage points), and AD (68%), followed by ECD (only 47% fall between 0 and +5), and they may vary with temperature, food and other factors. The differences tend to increase (esp. for ECD and ECI) when comparing later with earlier instars. Energy > DW efficiency values are commonly expected for AD because of the generally greater energy content of food than feces, and for ECD and ECI because of the generally greater energy content of insect biomass than ingested and assimilated food. Deviations from predicted differences in surveyed literature data are discussed in terms of possible methodological sources of error.
Résumé Plus de 80% des valeurs de la digestibilité approchée (AD), de l'efficacité de la conversion de la nourriture assimilée en biomasse (ECD) et de l'efficacité de la conversion de l'aliment ingéré (ECI), calculées en termes énergétiques, et obtenus à partir de données sur 65 espèces, sont supérieures aux valeurs des poids secs correspondants (DW): 38 études; valeurs comparatives: AD=139, ECD=128, ECI=169. Les plus importantes différences positive (énergie>valuers DW) sont de 30 (AD, ECD) et de 24 (ECI) centièmes (les différences négatives les plus fortes = 9 (AD), 11 (ECD) et 8 (ECI); ces différences sont moindres pour ECI (71% des différences tombent à 0 et +5 centièmes), et AD (68%), suivi de ECD (seulement 47% tombent entre 0 et +5). Ces différences peuvent varier avec la température, l'alimentation et d'autres facteurs; les différences tendent à croître (particulièrement pour ECD et ECI) quant on les compare plus tard avec des stades plus précoces. Energie > aux valeurs d'efficacité DW sont généralement attendues pour AD par suite du contenu énergétique supérieur de l'aliment à celui des excréments, et pour ECD et ECI par suite du contenu énergétique généralement plus élevé pour la biomasse de l'insecte que pour l'aliment ingéré et assimilé. Les écarts par rapport aux différences prédites dans les données de la littérature examinée sont analysées en considérant les sources possibles d'erreurs méthodologiques.
  相似文献   
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Because of the large μ mass compared to the electron mass, the muonic X-rays have energies very suitable for standard γ-ray spectroscopy (Ge detectors), so every element is easily recognized. By selecting the primary μ energies appropriately any part of the specimen, also well inside, can be nondestructively investigated. On the other hand, surface layers may be analyzed. Accuracies of quantitative analyses are 1% of the atomic abundance of the element in question in favorite cases. Results on applications in nuclear medicine and surface physics are presented, and ways of improving the muon flux density are discussed.  相似文献   
6.
Degradation of 3-chlorobiphenyl by in vivo constructed hybrid pseudomonads   总被引:13,自引:0,他引:13  
Abstract 3-Chlorobiphenyl-degrading bacteria were obtained from the mating between Pseudomonas putida strain BN10 and Pseudomonas sp. strain B13. Strains such as BN210 resulted from the transfer of the genes coding the enzyme sequence for the degradation of chlorocatechols from B13 into BN10, whereas B13 derivatives such as B131 have acquired the biphenyl degradation sequence from BN10. During growth of the hybrid strains on 3-chlorobiphenyl 90% chloride was released. Activities of phenylcatechol 2,3-dioxygenase, benzoate dioxygenase, catechol 1,2-dioxygenase, chloromuconate cyloisomerase and 4-carboxymethyl-enebut-2-en-4-olide hydrolase were found in 3-chlorobiphenyl-grown cells. The hybrid strains were found to convert some congeners of the Aroclor 1221 mixture such as mono- and dichloro-substituted biphenyls.  相似文献   
7.
Summary Locust lipoproteins (lipophorins) were localized by indirect immunofluorescence- and immunogold labelling in cryosections of dorsolongitudinal flight muscles. Immunolabelling was performed with monoclonal antibodies against apolipoprotein epitopes that are exposed at the surfaces of the lipophorin particles. Both at rest and during flight, lipophorins were located only in the wider spaces of the extracellular matrix, in the basement membranes of the individual muscle fibers and in the extracellular spaces that surround interfibrillar tracheoles. No internalization of lipophorins by the flight muscle cells was observed. Our results indicate that the unloading of lipophorins at the flight muscles is an extracellular event. Similarities with the vertebrate system of chylomicron and very-low-density lipoprotein degradation are discussed.  相似文献   
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黑河林区驼鹿冬季食性研究   总被引:4,自引:0,他引:4  
1987—1988年在黑龙江省黑河林区,应用粪便显微组织学分析技术,结合野外啃食调查,对驼鹿冬季食物组成、食物选择性和利用率进行了研究。结果表明,冬季驼鹿共采食31种(属)植物,其中柳、榛、桦、红松、杨和紫椴是主要的冬季食物(19.9%、18.0%、16.7%、14.9%、7.3%和6.7%)。驼鹿对杨、柳、红松和紫椴有正选择性,对榛、桦和毛赤杨有负选择性。选择性的强弱顺序为:杨>柳>红松>紫椴>榛>桦>毛赤杨。驼鹿对柳的选用率最高(32.1%),对桦的利用率最低(12.1%)。  相似文献   
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Abstract.
  • 1 Three aspects of prey utilization are documented in a guild of spider-hunting pompilid wasps at a Breckland heath site: female phenology, size, and microhabitat utilization.
  • 2 Twenty-four species were present at the site, 59% of the British fauna. Ten species individually represented more than 1% of the guild.
  • 3 Pompilid abundance peaked in early July and mid-late August. Anoplius viaticus had a different life-history from other common guild members, making its inclusion in the guild questionable.
  • 4 Most species represented by large samples occurred in all microhabitats and time intervals, and all species overlapped in size with all other species except A. viaticus. Arachnospila anceps was numerically dominant in all microhabitats and most time intervals.
  • 5 Mean pair-wise overlaps in phenology and microhabitat utilization were significantly lower than predicted by null models, consistent with the idea that interspecific competition has been important in determining guild structure.
  • 6 Female size is highly correlated with prey size, but the distribution of mean female sizes did not generally differ from null expectations.
  • 7 Interpretation of comparisons with null models is problematic, particularly because it is difficult to quantify evolutionary ‘favourability’ of different resource states. Null models are currently of limited use because the patterns expected to result from key processes such as competition are uncertain in multi-dimensional systems.
  相似文献   
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