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951.
Rieping W Habeck M Bardiaux B Bernard A Malliavin TE Nilges M 《Bioinformatics (Oxford, England)》2007,23(3):381-382
Modern structural genomics projects demand for integrated methods for the interpretation and storage of nuclear magnetic resonance (NMR) data. Here we present version 2.1 of our program ARIA (Ambiguous Restraints for Iterative Assignment) for automated assignment of nuclear Overhauser enhancement (NOE) data and NMR structure calculation. We report on recent developments, most notably a graphical user interface, and the incorporation of the object-oriented data model of the Collaborative Computing Project for NMR (CCPN). The CCPN data model defines a storage model for NMR data, which greatly facilitates the transfer of data between different NMR software packages. Availability: A distribution with the source code of ARIA 2.1 is freely available at http://www.pasteur.fr/recherche/unites/Binfs/aria2. 相似文献
952.
Given the growing amount of biological data, data mining methods have become an integral part of bioinformatics research. Unfortunately, standard data mining tools are often not sufficiently equipped for handling raw data such as e.g. amino acid sequences. One popular and freely available framework that contains many well-known data mining algorithms is the Waikato Environment for Knowledge Analysis (Weka). In the BioWeka project, we introduce various input formats for bioinformatics data and bioinformatics methods like alignments to Weka. This allows users to easily combine them with Weka's classification, clustering, validation and visualization facilities on a single platform and therefore reduces the overhead of converting data between different data formats as well as the need to write custom evaluation procedures that can deal with many different programs. We encourage users to participate in this project by adding their own components and data formats to BioWeka. Availability: The software, documentation and tutorial are available at http://www.bioweka.org. 相似文献
953.
In birds, the link between parental care behaviour and prolactin release during incubation persists after hatching in altricial birds, but has never been precisely studied during the whole rearing period in precocial species, such as ducks. The present study aims to understand how changes in parental care after hatching are related to circulating prolactin levels in mallard hens rearing ducklings. Blood was sampled in hens over at least 13 post-hatching weeks and the behaviour of the hens and the ducklings was recorded daily until fledging. Contacts between hens and the ducklings, leadership of the ducklings and gathering of them steadily decreased over post-hatching time. Conversely, resting, preening and agonistic behaviour of hens towards ducklings increased. Plasma prolactin concentrations remained at high levels after hatching and then fell after week 6 when body mass and structural size of the young were close to those of the hen. Parental care behaviour declined linearly with brood age, showed a disruption of the hen-brood bond at week 6 post-hatching and was related to prolactin concentration according to a sigmoid function. Our results suggest that a definite threshold in circulating prolactin is necessary to promote and/or to maintain post-hatching parental care in ducks. 相似文献
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957.
Effects of AiiA-mediated quorum quenching in Sinorhizobium meliloti on quorum-sensing signals, proteome patterns, and symbiotic interactions 总被引:1,自引:0,他引:1
958.
Cerebellar LTD and pattern recognition by Purkinje cells 总被引:2,自引:0,他引:2
Steuber V Mittmann W Hoebeek FE Silver RA De Zeeuw CI Häusser M De Schutter E 《Neuron》2007,54(1):121-136
Many theories of cerebellar function assume that long-term depression (LTD) of parallel fiber (PF) synapses enables Purkinje cells to learn to recognize PF activity patterns. We have studied the LTD-based recognition of PF patterns in a biophysically realistic Purkinje-cell model. With simple-spike firing as observed in vivo, the presentation of a pattern resulted in a burst of spikes followed by a pause. Surprisingly, the best criterion to distinguish learned patterns was the duration of this pause. Moreover, our simulations predicted that learned patterns elicited shorter pauses, thus increasing Purkinje-cell output. We tested this prediction in Purkinje-cell recordings both in vitro and in vivo. In vitro, we found a shortening of pauses when decreasing the number of active PFs or after inducing LTD. In vivo, we observed longer pauses in LTD-deficient mice. Our results suggest a novel form of neural coding in the cerebellar cortex. 相似文献
959.
A novel method to monitor insulin-stimulated GTP-loading of Rab11a in cardiomyocytes 总被引:1,自引:0,他引:1
As a member of the Rab small GTPase family, Rab11a has been shown to be involved in different vesicle trafficking processes. In earlier work we identified Rab11a to be present in GLUT4-containing vesicles after insulin stimulation and showed its involvement in insulin-dependent glucose uptake. However, it remained elusive if Rab11a is directly activated by the insulin signalling cascade and at which step a potential activation occurs. To examine the GTP-loading of Rab11a, we introduced a biotinylated GTP-analog into H9c2-hIR cells, transiently overexpressing HA-tagged Rab11a, and measured its binding to the GTPase after insulin stimulation. We observed that Rab11a is transiently GTP-loaded after insulin stimulation with a 2.3 (+/-0.3) fold activation (n=5), reaching its maximum after 4 min and declining back to basal after additional 2 min. The activation of Rab11a is phosphatidylinositol 3-kinase (PI3-kinase) dependent and downstream of Akt, as shown by in vitro knockdown of this kinase. These data show that Rab11a is directly activated by insulin and represents an element of the GLUT4 trafficking machinery. 相似文献
960.
In order to gain further experience regarding the tolerability of Pinimenthol® ointment1 in adolescents (⩾12 years) and adults suffering from upper respiratory tract infections, a post-marketing observational study was performed. In this study, data of 3060 patients were collected (64.9% prospectively over an individual observation period of 5–14 days, 35.1% retrospectively). The prospective documentation also comprised data concerning treatment effects.Sample size of the post-marketing observational study was calculated in the way that adverse drug reactions with an event probability of at least 1:1000 would occur within the study at least once with a probability of 95%.Most patients suffered from cold, acute or chronic bronchitis, bronchial catarrh or hoarseness. Pinimenthol® ointment was prescribed to inunction (29.6%), inhalation (17.3%) or inunction and inhalation (53.1%), respectively. The mean duration of study participation was 8.0±3.4 days.The tolerability was rated as excellent or good by 96.7% of physicians and 95.7% of patients. A total of 22 patients (0.7%) reported adverse drug reactions which mostly affected the skin or mucus membrane and therefore correspond to the expected adverse effects profile of Pinimenthol® ointment. The treatment effect was mostly judged as excellent or good (physicians: 88.3%; patients: 88.1%).In conclusion, the study confirms Pinimenthol® ointment as a well tolerated therapy option for upper respiratory tract infections in both adolescents and adults. 相似文献