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851.
852.
Neural receptor-linked protein tyrosine phosphatases (RPTPs) are required for guidance of motoneuron and photoreceptor growth cones in Drosophila. These phosphatases have not been implicated in growth cone responses to specific guidance cues, however, so it is unknown which aspects of axonal pathfinding are controlled by their activities. Three RPTPs, known as DLAR, DPTP69D, and DPTP99A, have been genetically characterized thus far. Here we report the isolation of mutations in the fourth neural RPTP, DPTP10D. The analysis of double mutant phenotypes shows that DPTP10D and DPTP69D are necessary for repulsion of growth cones from the midline of the embryonic central nervous system. Repulsion is thought to be triggered by binding of the secreted protein Slit, which is expressed by midline glia, to Roundabout (Robo) receptors on growth cones. Robo repulsion is downregulated by the Commissureless (Comm) protein, allowing axons to cross the midline. Here we show that the Rptp mutations genetically interact with robo, slit and comm. The nature of these interactions suggests that DPTP10D and DPTP69D are positive regulators of Slit/Roundabout repulsive signaling. We also show that elimination of all four neural RPTPs converts most noncrossing longitudinal pathways into commissures that cross the midline, indicating that tyrosine phosphorylation controls the manner in which growth cones respond to midline signals.  相似文献   
853.
We report the draft genome sequence of a clinical isolate, strain M115, identified as Mycobacterium massiliense, a member of the newly created taxon of Mycobacterium abscessus subspecies bolletii comb. nov.  相似文献   
854.
Mycobacterium massiliense is a rapidly growing mycobacterial species. The pathogenicity of this subspecies is not well known. We report here the annotated genome sequence of M. massiliense strain M18, which was isolated from a lymph node biopsy specimen from a Malaysian patient suspected of having tuberculous cervical lymphadenitis.  相似文献   
855.
The genome of Mycobacterium massiliense M172, isolated from a human sputum sample, was sequenced using Illumina GA IIX technology and found to contain 5,204,460 bp, including putative genes for virulence and antibiotic resistance as well as a 92-kb genomic region most likely to correspond to a mycobacteriophage.  相似文献   
856.
857.
A novel benzoylphloroglucinol derivative, garcimultiflorone D ( 1 ), with an unusual adamantyl‐caged skeleton was isolated from the fruits of Garcinia multiflora, together with four known compounds. The structure of 1 was determined through extensive 1D/2D‐NMR and mass‐spectrometric analyses. Garcimultiflorone D ( 1 ) exhibited inhibitory activities with IC50 values of 7.21±1.07 and 6.01±0.37 μg/ml against fMLP/CB‐induced superoxide anion generation and elastase release, respectively.  相似文献   
858.
As a wide‐bandgap semiconductor, titanium dioxide (TiO2) with a porous structure has proven useful in dye‐sensitized solar cells, but its application in low‐cost, high‐efficiency inorganic photovoltaic devices based on materials such as Cu(InGa)Se2 or Cu2ZnSnS4 is limited. Here, a thin film made from solution‐processed TiO2 nanocrystals is demonstrated as an alternative to intrinsic zinc oxide (i‐ZnO) as the window layer of CuInSxSe1?x solar cells. The as‐synthesized, well‐dispersed, 6 nm TiO2 nanocrystals are assembled into thin films with controllable thicknesses of 40, 80, and 160 nm. The TiO2 nanocrystal films with thicknesses of 40 and 80 nm exhibit conversion efficiencies (6.2% and 6.33%, respectively) that are comparable to that of a layer of the typical sputtered i‐ZnO (6.42%). The conversion efficiency of the devices with a TiO2 thickness of 160 nm decreases to 2.2%, owing to the large series resistance. A 9‐hour reaction time leads to aggregated nanoparticles with a much‐lower efficiency (2%) than that of the well‐dispersed TiO2 nanoparticles prepared using a 15‐hour reaction time. Under optimized conditions, the champion TiO2 nanocrystal‐film‐based device shows even higher efficiency (9.2%) than a control device employing a typical i‐ZnO film (8.6%).  相似文献   
859.
microRibonucleic acid (miRNAs) are small regulatory molecules that act by mRNA degradation or via translational repression. Although many miRNAs are ubiquitously expressed, a small subset have differential expression patterns that may give rise to tissue-specific complexes. MOTIVATION: This work studies gene targeting patterns amongst miRNAs with differential expression profiles, and links this to control and regulation of protein complexes. RESULTS: We find that, when a pair of miRNAs are not expressed in the same tissues, there is a higher tendency for them to target the direct partners of the same hub proteins. At the same time, they also avoid targeting the same set of hub-spokes. Moreover, the complexes corresponding to these hub-spokes tend to be specific and nonoverlapping. This suggests that the effect of miRNAs on the formation of complexes is specific.  相似文献   
860.
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