1,721,048 research outputs found
Genome methylation of the marine annelid worm Chaetopterus variopedatus:methylation of a CpG in an expressed H1 histone gene.
No full textOccurrence of genetic exchange in the environment between natural and laboratory microorganisms:plasmids in psichrophilic bacteria of italian natural spring waters.
No full textPercutaneous Nephrostomy Catheter Misplacement into Inferior Vena Cava in a Patient with a Horseshoe Kidney
No full textBackground: Percutaneous nephrostomy (PCN) is commonly indicated for upper urinary tract drainage in case of obstruction or fistula. Only a few cases of PCN catheter misplacement into the inferior vena cava (IVC) have been published. Case Presentation: We report a case of a PCN catheter misplaced into the IVC through a fistula between the urinary tract and an ipsilateral renal vein in a patient with horseshoe kidney, after bedside urgent replacement for hemorrhage and hemorrhagic shock. Conclusion: Although a nephrostomy Foley catheter can be used for adequate urinary drainage and hemostatic purposes after percutaneous nephrolithotomy, its placement should be always verified through antegrade pyelography and particular care should be used for horseshoe kidneys. In case of massive hemorrhage, after temporary closure of the PCN catheter, the cause of bleeding should be investigated with urgent angiography or contrast-enhanced CT scan and promptly treated
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Characterization of a new variant DNA (cytosine-5)-methyltranferase unable to methylate double stranded DNA isolated from the marine annelid worm Chaetopterus variopedatus.
No full textThe enzyme S-adenosylmethionine-DNA (cytosine-5)-methyltransferase has been identified, first time for invertebrates, in embryos of the marine polychaete annelid worm Chaetopterus variopedatus. The molecule has been isolated from embryos at 15 h of development. It is a single peptide of about 200 kDa molecular weight, cross-reacting with antibodies against sea urchin DNA methyltransferase. The enzymatic properties of the molecule are similar to those of Dnmt1 methyltransferases isolated from other organisms, but with the peculiarity to be unable to make 'de novo' methylation on double stranded DNA. Copyright (C) 1999 Federation of European Biochemical Societies
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
GNG5 Controls the Number of Apical and Basal Progenitors and Alters Neuronal Migration During Cortical Development
Full text linkCortical development is a very complex process in which any temporal or spatial alterations can give rise to a wide range of cortical malformations. Among those malformations, periventricular heterotopia (PH) is characterized by clusters of neurons that do not migrate to the correct place. Cerebral organoids derived from patients with mutations in DCHS1 and FAT4, which have been associated with PH, exhibit higher levels of GNG5 expression in a patient-specific cluster of neurons. Here we investigate the role of GNG5 during the development of the cerebral cortex in mice and human cerebral organoids. GNG5, highly expressed in progenitors and downregulated in neurons, is critical for controlling the number of apical and basal progenitors and neuronal migration. Moreover, forced expression of GNG5 recapitulates some of the alterations observed upon downregulation of Dchs1 and Fat4 in mice and human cerebral organoids derived from DCHS1 and FAT4 patients, suggesting a critical role of GNG5 in cortical development
- …
