1,720,955 research outputs found
Measuring the quality of early treatment of head injured patients
No full textEarly treatment of head injured patients can affect the prognosis; therefore it is useful to define some parameters related to the quality and time of the first aid. The occurrence of hypoxia, hypotension, seizures and presence of foreign bodies in the airways has been recorded in more than 300 head injured patients admitted to Intensive Care Unit during a 3 years period. Patients are classified using APACHE. Trauma Score, Glasgow Coma Score and other indices of trauma severity. After the first evaluation the patients have undergone an intensive treatment including mechanical ventilation, haemodynamic monitoring and intracranial pressure monitoring. Outcome was assessed six month after the trauma using the Glasgow Outcome Score: relationships between the parameters recorded at the admission and the clinical course were investigated, with particular emphasis on inhalation and the occurrence of pneumonia during the first week of intensive treatment. Factors of secondary brain damage (hypoxia, hypotension, seizures, inhalation and delayed treatment) are detected in a high percentage of trauma patients and the time elapsing between trauma and hospitalization is still too long, sometimes exceeding four hours; they are related to a mortality rate averaging the 40% and a rate of severely disabled patients of 7%
Hémorragie sous-arachnoïdienne : lésion cérébrale, équilibre hydrique, pression intracrânienne et relation pression-volume
No full textChanges in osmolality and electrolyte concentrations are observed frequently in patients with subarachnoid haemorrhage (SAH). Intracranial pressure (ICP) plays a determinant role in the development of secondary brain damage following SAH and may be caused by haemorrhage itself, oedema formation and disturbance of cerebrospinal fluid (CSF) dynamics. The relationships among these factors are the aim of this investigation. In 17 comatose SAH patients, ICP was monitored through a ventricular catheter; serial of pressure-volume index (PVI) and CSF formation and reabsorption were performed. Arterio-jugular differences for oxygen and lactate were measured. The average ICP recorded for each 12 hour interval was 18.9 mmHg (SD = 5.9); mean cerebral perfusion pressure (CPP) was 75 mmHg (SD = 13); the lowest CPP value was 30 mmHg. Mean PVI was 22.7 mL (SD = 7.4), ranging from 5 to 36. Eleven patients however, showed a PVI less than 15 mL at some point during testing. Values of CSF dynamics indicated disturbances of CSF reabsorption in 11 cases. When the cause of ICP rise was identified in CSF disturbances, treatment was successful, even in case of reduced PVI. Mean C(a-v)O2, corrected for a PaCO2 of 40 mmHg, was 3.7 mL.dL-1 (SD = 1.1) ranging from the extremely low value of 0.2 to 6.8 mL.L-1. Three patients with extremely low C(a-v)O2 values showed a cerebral production of lactate and developed areas of ischaemia on the CT scan. Hyponatraemia, considered as a sodium plasma concentration of less than 135 mmol.L-1, was detected in seven patients. Hyponatraemia was treated by infusion of hypertonic sodium solutions. Mannitol (1 g.kg-1.d-1 in four doses) was infused if the sodium plasma concentration was not corrected by the former treatment or if ICP exceeded 20 mmHg. Treatment was aimed at preserving cerebral perfusion by providing adequate pre-load, low viscosity (Ht 30%) and sustained arterial pressure. Correction of hyponatraemia was therefore achieved more through hypertonic fluids infusion than by using diuretics
Cerebral venous oxygen saturation studied with bilateral samples in the internal jugular veins
No full textThe current literature reports many measurements (arteriovenous oxygen content difference and cerebral metabolic rate of oxygen, etc.) with samples from the internal jugular veins (IJs), obtained from either side of the neck, based on the assumption that a reliable sample of mixed venous blood can be drawn. We compared oxygen saturation in both IJs in 32 patients with head injuries to establish the similarities or discrepancies in the two veins. Both IJs were cannulated with 20-G catheters; in five patients, a fiberoptic catheter was used to obtain a continuous recording of the hemoglobin saturation. Blood samples were taken simultaneously from the two IJs and immediately processed; the total number of samples processed was 342, with an average of 5.34 paired samples from each patient. The mean and the standard deviation of the differences between the saturation of the two IJs were, respectively, 5.32 and 5.15. Fifteen patients showed differences greater than 15% in hemoglobin saturation; three more patients showed differences greater than 10% at some point during the investigation. Ultimately, only eight patients had differences of less than 5%. No relationship was found among the computed tomographic scan data and the pattern of hemoglobin saturation detected. Therefore, we were not able to identify the side more appropriate for monitoring in patients with bilateral, predominantly monolateral, cortical, or deeply located lesions.The 95% confidence limits for the percentage of patients with a difference higher than 15% were between 30 and 64%; the limits for the percentage of patients with a difference higher than 10 were between 39 and 73%; ultimately, the limits for the percentage of patients with a difference higher than 5 were between 60 and 90%. The proportion of patients with relevant discrepancies between the two IJs is higher than suspected, and the reliability of a single item of data obtained from a single IJ is questionable
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
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
- …
