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Anatomical resection of left liver segments
No full textHypothesis: Anatomical resection of the left liver segments are rarely mentioned in the literature. We describe an anatomical access to the left liver segments\u92 pedicles without hilar dissection.
Design Original surgical technique.
Patients and Methods This technique was used in 26 consecutive resections involving left liver segments between July 2001 and December 2003. There were 15 men and 11 women with mean age of 57.1 years. Eleven patients had liver metastasis, 8 had primary liver cancer, 6 had benign lesions, and 1 had gallbladder cancer. The technique consists of small liver incisions according to anatomical landmarks such as the Arantius and round ligaments. In a systematized way, it was possible to reach every glissonian sheath of segments II, III, and IV.
Results: Liver resection was feasible using the proposed technique in every patient of this series, and the Pringle maneuver was not required in any patient. Intraoperative blood loss was minimal in all cases, and 23 patients did not require blood transfusion. There was no postoperative death.
Conclusions :This operative procedure allows easy, fast access for anatomical resection of the left liver segments. It is useful for performing controlled hepatectomies without clamping the main hepatic pedicle and may facilitate the recognition of all left liver segment sheaths, with excellent immediate results
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Study of the anatomy of liver landmarks for the intrahepatic approach to glissonian pedicles during hepatectomies
No full textRessecções hepáticas regradas baseiam-se em alguns princípios técnicos básicos, como controle vascular, delineamento isquêmico das áreas a serem ressecadas e preservação máxima de parênquima. Eles são alcançados através do acesso intrahepático aos pedículos glissonianos, que se baseia na abordagem dos segmentos hepáticos através do acesso aos pedículos dentro do fígado. Com pequenas incisões sobre pontos de reparo anatômicos bem definidos são acessados pedículos correspondentes aos segmentos a serem ressecados, tornando desnecessárias dissecções extensas do parênquima hepático.Neste estudo, parâmetros anatômicos relacionados à técnica de acesso intra-hepático aos pedículos glissonianos foram estudados em cadáveres com o fígado in loco. Ele propiciou a determinação precisa de pontos de reparo confiáveis e simples a serem utilizados durante estes procedimentos.Foram estudados 37 fígados provenientes de cadáveres adultos. Vinte e cinco cadáveres eram do sexo masculino e doze do sexo feminino. Foram excluídos cadáveres que tivessem qualquer fator que alterasse a anatomia original do andar superior do abdome e fígados com aspecto cirrótico. As aferições realizadas foram realizadas com instrumentos de precisão. Os dados obtidos foram expressos em média ± desvio padrão. Os indivíduos foram então divididos em grupos de acordo com gênero e peso do fígado e os grupos foram comparados estatisticamente através do teste t de Student. Setenta por cento dos cadáveres apresentavam veia hepática direita acessória, sendo este achado muito superior ao encontrado na literatura. O diâmetro médio deste vaso, quando presente, foi de 6,8 mm. As veias hepáticas média e esquerda apresentavam tronco comum em direção à veia cava em 51% dos casos, valor menor do que o habitualmente encontrado na literatura.Em 70% dos fígados a fissura de Gans encontrava-se aberta. Nestes, 80% continha o pedículo do segmento 6. A ponte entre os segmentos 3 e 4 encontrava-se aberta em 41% dos casos.O diâmetro médio do pedículo esquerdo foi de 28,2 mm, enquanto o do direito foi de 26,8 mm.A distância média entre a bifurcação do tronco portal e a inserção caudal do ligamento de Arantius foi de 32,9 mm. Esta distância é importante na realização do acesso intra-hepático a pedículos esquerdos. A distância média entre a bifurcação do tronco portal principal e a do pedículo direito foi de 26,2 mm. Este valor deve ser levado em consideração no acesso aos pedículos do fígado direito.A distância máxima observada entre a placa hilar e a bifurcação do tronco portal representa quanto se deve aprofundar na placa hilar para acesso dos pedículos direito e esquerdo e foi de 7 mm.Não foi observada diferença estatisticamente significativa em praticamente todos os parâmetros avaliados quando comparados os grupos divididos de acordo com gênero e peso do fígado. Isso demonstra a consistência dos parâmetros relacionados à realização do acesso intra-hepático aos pedículos glissonianos, garantindo reprodutibilidade ao método.Os resultados obtidos tornaram possíveis grandes avanços técnicos na realização de hepatectomias abertas ou laparoscópicas com acesso intra-hepático aos pedículos glissonianos, e resultaram em uma série de dados anatômicos que podem guiar cirurgiões de modo a evitar acidentes e tornar mais fácil sua execuçãoAnatomical liver resections are based on some basic technical principles such as vascular control, ischemic delineation of areas to be resected and maximum parenchymal preservation. Those are achieved by the intrahepatic glissonian approach, which consists in accessing the pedicles of hepatic segments to be resected within the hepatic parenchyma. Small incisions on well-defined anatomical landmarks are performed to approach the desired pedicles, making extensive dissection of the liver parenchyma unnecessary.In this study, anatomical parameters related to the intrahepatic glissonian approach to hepatic pedicles were studied in cadavers with the liver in loco. It allowed the accurate determination of anatomical landmarks that are reliable and easy to be used.Thirty-seven livers from adult cadavers were studied. Twenty-five cadavers were male and twelve female. Corpses that had any factor that altered the original anatomy of the upper abdomen and cirrhotic livers were excluded. The measurementswere performed with precision instruments. Data were expressed as mean ± standard deviation. The subjects were divided into groups according to gender and liver weight and the groups were compared statistically by the Student t test.Seventy percent of the cadavers presented an accessory right hepatic vein, much more frequent than previously reported in the literature. The average diameter of the vesselwas 6.8 mm. The middle and left hepatic veins presented a common trunk in 51% of cases, lower than typically found in the literature.In 70% of livers there was a patent incisura dextra of Gans. When present, 80% contained the pedicle of segment 6. There was an open hepatic bridge between segments 3 and 4 in 41% of cases.The mean diameter of the left pedicle was 28.2 mm, while the mean diameter of the right pedicle was 26.8 mm.The mean distance between the bifurcation of the main portal trunk and the caudal insertion of Arantius ligament was 32.9 mm. This distance is important in achieving the intrahepatic access to left pedicles. The mean distance between the bifurcation of the main portal trunk and the right pedicle was 26.2 mm. This value should be taken into consideration when approaching pedicles of the right liver.The maximum distance between the hilar plate and the bifurcation of the main portal trunk was 7 mm. It represents how deep one should enter the hepatic parenchyma through the hilar plate in order to approach the right and left pedicles.No statistically significant difference was observed in virtually all parameters when groups divided according to gender and liver weight were compared. This demonstrates the consistency of the anatomical parameters related to the intrahepatic glissonian approach, ensuring reproducibility to the method. Theresults obtained in this study made possible major technical advances in the realization of open and laparoscopic hepatectomies with intrahepatic glissonian approach to hepatic pedicles, and resulted in a series of anatomical data that can guide surgeons to prevent accidents and make it easier to accomplish safe and effective procedure
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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