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The value of white blood cell count in the diagnosis of acute appendicitis. Utilità della leucometria nella diagnosi di appendicite acuta
No full textBACKGROUND:
The diagnosis of acute appendicitis remains a critical challenge for paediatric surgeons. White Blood Cell (WBC) count, once considered a basic exam, is still routinely performed in most institutions, despite its lack of accuracy. Aim of this study is to assess the additional value of WBC count in the diagnosis of acute appendicitis.
METHODS:
We retrospectively reviewed the charts of children who underwent appendectomy for acute appendicitis in the last two years at our institution. In the patients treated in 1999 (Group A), WBC count was assessed routinely after admission. The surgeons relied on leukocytosis as well as on clinical findings and on ultrasound abdominal scan for the diagnosis of acute appendicitis. In the patients treated in 2000 (Group B), blood cell count was not tested or deliberately ignored by the surgeons.
RESULTS:
There were 65 children in Group A and 70 in Group B; the two groups of patients were similar in terms of gender (p = 0.989) and age (p = 0.758). Criteria for operation were similar in the two groups (p = 0.222). No differences were found in the number of perforated (p = 0.989) and normal (p = 0.217) appendixes in the two groups as well as in the duration of hospital stay after surgery (p = 0.849).
CONCLUSIONS:
WBC count at admission has no proven additional value in the diagnosis of acute appendicitis and can be omitted without modifying diagnostic pathway and without affecting diagnostic accuracy
Leaf area is stimulated in Populus by free air CO2 enrichment (POPFACE), through increased cell expansion and production
No full textThe effects of free-air CO2 enrichment (FACE) on leaf growth in Populus, was studied. For the first time in field conditions, both the production and expansion of leaf cells were shown to be sensitive to atmospheric carbon dioxide. Leaf area expansion rate and final leaf size were stimulated under FACE for three species (Populus x euramericana (I-214), P. nigra (Jean Pourtet) and P. alba (2AS-11), with the largest effect observed for P. x euramericana (61%). In this species and in P. nigra, both epidermal cell size and cell number were increased, whereas for P. alba, only cell production was increased in FACE. Two findings suggest that changes in the cell wall may be important in explaining larger leaf cells in FACE: (i) Leaf cell wall extensibility of rapidly growing leaves increased in all species in FACE; and (ii) an increase in xyloglucan endotransglycosylase activity, a cell wall-loosening enzyme, was increased in FACE and associated with leaf growth rate. The results suggest that the mechanisms by which FACE promotes leaf growth differ, depending on species. Despite this, increases in final leaf size provide an important component driving increased biomass accumulation in POPFACE, during this first year of rapid growth, prior to canopy closure. The question as to whether these effects are the result of a direct response to CO2, or are driven indirectly through substrate availability remains unresolved, although evidence from the literature suggests that the latter mechanism is most likely
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
Carotid artery approach as an alternative to femoral access for balloon dilatation of aortic valve stenosis in neonates and infants
No full textPURPOSE: to evaluate the efficacy of a right common carotid artery cutdown as alternative access in neonates and small infants requiring a balloon dilation of aortic valve stenosis. In infants, the femoral approach is limited by difficulties in advancing the catheter across the valve and by the risk of femoral artery injuries
AXIAL AND RADIAL WATER-FLOW IN THE TRUNKS OF OAK TREES - A QUANTITATIVE AND QUALITATIVE-ANALYSIS
No full textAxial water flow in the trunks of mature oak trees (Quercus petraea (Matt.) Liebl. and Q. robur L.) was studied by four independent techniques: water absorption from a cut trunk, sap flowmeters, heat pulse velocity (HPV) and thermoimaging. Estimation of the total water flow with sap flowmeters, HPV and water absorption yielded comparable results. We concluded from dye colorations, thermograms and axial profiles of sap flow and heat pulse velocity that, in intact trunks, most of the flow occurred in the current-year ring, where early-wood vessels in the outermost ring were still functional. Nevertheless, there was significant flow in the older rings of the xylem. Total water flow through the trunk was only slightly reduced when air embolisms were artificially induced in early-wood vessels, probably because there was little change in hydraulic conductance in the root-leaf sap pathway. Embolization of the current-year vessels reactivated transport in the older rings
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
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