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1.
A library of cDNA clones was constructed representing polysomal polyadenylated RNA of mesenchyme blastulae of Strongylocentrotus purpuratus. Using this library, we determined whether or not individual RNA species are associated with animalization of embryos by zinc ions. Clones corresponding to the most actively synthesized RNAs during the period just prior to the mesenchyme blastula stage were selected by screening colonies with in vivo-labeled RNA. The most abundant of these were chosen for further study. Individual RNA abundance was measured as percent of mass of total polyadenylated RNA by hybridizing cDNA exhaustively with cloned DNA on filters. The RNAs in the selected, cloned sequences were present in abundances of 0.01 to 1% of the mass of polyadenylated RNA. Changes in abundance of individual RNA species occurred during normal development and departures from these developmental changes occurred in the zinc-animalized embryos. Two RNA species, which normally increase 10-fold in abundance, are drastically repressed and at least one RNA species increases in abundance dramatically in the animalized embryos. These departures from the normal program of presumptive gene expression may furnish insights into changes in the normal processes of development.  相似文献   
2.
Changes in the structure of benthic insect communities at an experimental site and at a reference site in the Ford River, Michigan were monitored over a 10-year period to determine whether extremely low frequency electromagnetic fields (ELF) affected those communities. Five of 10 biotic parameters monitored are presented: taxon evenness (J), richness (S), numerical dominance of chironomids, and total insect mass. Data were separated into three seasons because coefficient of variation values were lower in the summer than in the spring and fall. Two-way ANOVA tests for the biotic variables were often significantly different between sites and among years, but the interaction terms were less frequently significant. Biotic parameters were regressed against stream discharge, water temperatures, years, and ELF cumulative ground field exposures. At the experimental site, discharge accounted for more variation than did water temperature or years for all biotic parameters except chironomid numerical dominance in the fall. Intervention analyses, using the B.A.C.I parametric or the R.I.A non-parametric showed significant differences in three of 15 cases; namely, for the highly varying chironomid numerical dominance values in the spring and fall and for the low varying total insect mass values in the summer. For those tests, the Before Impact period spanned April 1984 through May 1986. The After Impact period (full ELF power) spanned June 1989 through August 1993. Trend analysis for total insect mass at the experimental site in the summer showed discharge to be more important than water temperatures or ELF ground field exposures. Natural physical factors appear to be more important than the anthropogenic ELF fields in accounting for seasonal and yearly changes in the community.  相似文献   
3.
Summary InStegodyphus sarasinorum Karsch the adult stage is attained after twelve instars. The secondary sexual characters become manifest in the twelfth instar. There is only one generation per year. Normally only one cocoon is made and taken care of by a fertilized female during her life-time.The various aspects of the bionomics and behaviour of this social spider, viz., the nest architecture, repair of webs, activity rhythm, food and feeding behaviour, population density at different stages, sex-ratio, sexual behaviour, maternal behaviour, dispersal and colony foundation, are discussed. Besides feeding her young ones during the second instar by regurgitation and by providing them with captured prey, the mother spider finally offers herself as a living food depot for her young ones which suck out her body fluids and she slowly dies.New colonies are formed after emigration over silken threads by either groups of spiderlings at various times in colonies during the fourth to ninth instars (sociotomy), or by individual fertilized females. In a second method of colony foundation, emigration of spiderlings of fourth to eighth instars takes place either by individuals or by small groups by means of silken threads produced and wafted in the wind (aerial navigation).
Résumé ChezStegodyphus sarasinorum Karsh, l'état adulte est atteint après 12 stades. Les caractères sexuels secondaires deviennent visibles au douzième. Il y a seulement une génération par an. Normalement, durant sa vie, une femelle ne tisse et soigne qu'un seul cocon.On a analysé les différents aspects de la bionomie et du comportement de cette araignée sociale, c'est-à-dire l'architecture du nid, réparation de la toile, rythme d'activité, nourriture et comportement alimentaire, densité de population aux différents stades, sex-ratio, comportement sexuel, comportement maternel, dispersion et fondation de colonies. En plus du nourrissage de ses enfants au deuxième stade par régurgitation et apport de proies capturées, la mère s'offre finalement comme réserve vivante de nourriture pour ses enfants qui pompent la lymphe et elle meurt lentement.De nouvelles colonies apparaissent par migration sur fils de soie ou bien de jeunes du quatrième au neuvième stade à différents moments de la colonie, ou bien de femelles fécondées seules. Dans une deuxième méthode de fondation de colonie, la migration des jeunes du quatrième au huitième stade se fait seule ou en petits groupes par production de fils de soie et transport aérien.
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4.

Background

The ability to apply standard and interoperable solutions for implementing and managing medical registries as well as aggregate, reproduce, and access data sets from legacy formats and platforms to advanced standard formats and operating systems are crucial for both clinical healthcare and biomedical research settings.

Purpose

Our study describes a reproducible, highly scalable, standard framework for a device registry implementation addressing both local data quality components and global linking problems.

Methods and Results

We developed a device registry framework involving the following steps: (1) Data standards definition and representation of the research workflow, (2) Development of electronic case report forms using REDCap (Research Electronic Data Capture), (3) Data collection according to the clinical research workflow and, (4) Data augmentation by enriching the registry database with local electronic health records, governmental database and linked open data collections, (5) Data quality control and (6) Data dissemination through the registry Web site. Our registry adopted all applicable standardized data elements proposed by American College Cardiology / American Heart Association Clinical Data Standards, as well as variables derived from cardiac devices randomized trials and Clinical Data Interchange Standards Consortium. Local interoperability was performed between REDCap and data derived from Electronic Health Record system. The original data set was also augmented by incorporating the reimbursed values paid by the Brazilian government during a hospitalization for pacemaker implantation. By linking our registry to the open data collection repository Linked Clinical Trials (LinkedCT) we found 130 clinical trials which are potentially correlated with our pacemaker registry.

Conclusion

This study demonstrates how standard and reproducible solutions can be applied in the implementation of medical registries to constitute a re-usable framework. Such approach has the potential to facilitate data integration between healthcare and research settings, also being a useful framework to be used in other biomedical registries.  相似文献   
5.
The demand for biomaterials with properties that provide sustained release of substances with pharmacological interest is constant. One candidate for applications in this area is the Natural Rubber Latex (NRL) extracted from the rubber tree Hevea brasiliensis. Recent studies indicate the NRL as a matrix for sustained release, showing promising results for biomedical applications such as: can stimulate natural angiogenesis and is capable of adhering cells on its surface, promoting the replacement and regeneration of tissue. So, the NRL is an excellent candidate to propitiate the sustained release of peptides of pharmacological interest such as oxytocin, a hormonal peptide which has the function to promote uterine muscle contractions and reduce bleeding during childbirth, and stimulate the release of breast milk. Results demonstrated that 90 μg mL?1 (45 %) of the incorporated peptide in Natural Rubber Latex Biomedical (NRLb) functionalized membranes was released at 10 h in phosphate-buffered saline (PBS) solution. Swelling kinetics assay showed that the NRLb membranes are able to absorb over a period of 16 h up to 1.08 grams of water per grams of membrane. Scanning electron microscopy showed that the peptide was adsorbed on the surface and within NRLb membrane. Fourier transform infrared and Derivative Thermogravimetric analysis indicated that oxytocin did not interacted chemically with the membrane. Furthermore, hemolysis of erythrocytes, quantified spectrophotometrically using materials (Oxytocin, NRLb, and NRLb + Oxytocin) showed no hemolytic effects up to 100 μg mL?1 (compounds and mixtures), indicating no detectable disturbance of the red blood cell membranes. Based on these results it was possible to conclude that the NRLb has shown effectiveness as a model in the release of peptides with pharmacological interest.  相似文献   
6.
7.
The dodecamer universal minicircle sequence is a conserved sequence present in minicircles of trypanosomatid kinetoplast DNA studied so far. This sequence is recognised by a protein named universal minicircle sequence binding protein, described for Crithidia fasciculata, involved in minicircle DNA replication. We have identified a Trypanosoma cruzi gene homologue of the Crithidia fasciculata universal minicircle sequence binding protein. Similar to the Crithidia fasciculata universal minicircle sequence binding protein, the Trypanosoma cruzi protein, named PDZ5, contains five zinc finger motifs. Pulsed field gel electrophoresis indicated that the pdz5 gene is located in the chromosomal band XX of the Trypanosoma cruzi genome. The predicted amino acid sequence of PDZ5 shows a high degree of similarity with several trypanosomatid zinc finger proteins. Specific antibody raised against Crithidia fasciculata universal minicircle sequence binding protein recognises both the recombinant and endogenous PDZ5. The complete pdz5 coding sequence cloned in bacteria expresses a recombinant PDZ5 protein that binds specifically to the universal minicircle sequence dodecamer. These data strongly suggest that PDZ5 represents a Trypanosoma cruzi universal minicircle sequence binding protein.  相似文献   
8.
A Clock polymorphism T to C situated in the 3' untranslated region (3'-UTR) has been associated with human diurnal preference. At first, Clock 3111C had been reported as a marker for evening preference. However these data are controversial, and data both corroborating and denying them have been reported. This study hypothesizes that differences in Clock genotypes could be observed if extreme morning-type subjects were compared with extreme evening-type subjects, and the T3111C and T257G polymorphisms were studied. The possible relationship between both polymorphisms and delayed sleep phase syndrome (DSPS) was also investigated. An interesting and almost complete linkage disequilibrium between the polymorphisms T257G in the 5' UTR region and the T3111C in the 3' UTR region of the Clock gene is described. Almost always, a G in position 257 corresponds to a C in position 3111, and a T in position 257 corresponds to a T in position 3111. The possibility of an interaction of these two regions in the Clock messenger RNA structure that could affect gene expression was analyzed using computer software. The analyses did not reveal an interaction between those two regions, and it is unlikely that this full allele correspondence affects Clock gene expression. These results show that there is no association between either polymorphism T3111C or T257G in the Clock gene with diurnal preference or delayed sleep phase syndrome (DSPS). These controversial data could result from the possible effects of latitude and clock genes interaction on circadian phenotypes.  相似文献   
9.

The species Piper hispidinervum, Piper aduncum, and Piper affinis hispidinervum have essential oils with high levels of safrole, dillapiole, and sarisan, respectively. Safrole is important for pharmaceutical and chemical industries, while dillapiole and sarisan are promising compounds to control insects and fungi. These species are very similar morphologically and their taxonomy is controversial. Divergent hypotheses consider P. aduncum and P. hispidinervum either as a single species or as distinct taxa, while P. affinis hispidinervum is inferred to be a natural hybrid or a chemotype of P. hispidinervum. Delimiting the taxonomic boundaries would be helpful for germplasm conservation and breeding programs. This study aimed to undertake a detailed analysis of P. aduncum, P. hispidinervum, and P. affinis hispidinervum karyotype and rDNA sites. Genomic in situ hybridization (GISH) was used to establish genomic homology among species and to test the natural hybridization hypothesis for origin of P. affinis hispidinervum. Karyotype traits were similar for all three species: 2n = 26 small chromosomes, predominantly metacentric. All three species exhibited CMA+ bands on the secondary constriction of chromosome pair 4. A size-heteromorphic 35S rDNA site was co-localized with the CMA+ band. A 5S rDNA site was located in the proximal region of chromosome pair 7. The patterns of genomic hybridization revealed that the repetitive DNA fraction of the species is highly similar in terms of proportion of genome, sequence type, and distribution. Our findings did not allow us to differentiate the three species and point to the importance of deeper genomic studies to elucidate the taxonomic controversy.

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10.
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