1,720,970 research outputs found
Obstructive sleep apnea syndrome in patients with normal body weight: pathophysiologic, clinical and therapeutic aspects
No full textThe prevalence of obstructive sleep apnea syndrome (OSAS) in the general population is considerably high. The epidemiologically most important factor is obesity, since increased adipose tissue leads to alterations in upper airway anatomy and function that can trigger the mechanisms underlying the syndrome. While the bulk of published studies focus on OSAS in patients with an elevated body mass index (BMI), few have investigated the anatomical and pathophysiologic implications of OSAS in patients with normal body weight. In a previous study, the authors found that among these patients the primary anatomic anomaly contributing to the onset of OSAS was hypertrophy of the base of tongue, while septal deviation was a concurrent cause of the syndrome. Morphometric and physiologic studies have highlighted several other differences between OSAS sufferers with normal and those with elevated BMI. With this review the authors describe the anatomic, functional, clinical and therapeutic aspects of OSAS in patients with normal body weight
Peripheral vestibular damage causes impaired navigation tasks on memorized routes in humans
No full textOBJECTIVES: To investigate if a well-compensated unilateral peripheral vestibular hypofunction could interfere with navigation tasks on memorized routes in humans. METHODS: After a complete otoneurological investigation, fifty labyrinthine-defective patients and fifty controls were invited to visually memorize three different routes (a triangle, a circle and a square) on a grey carpet and then to walk along them with eye closed clockwise and counter-clockwise (mental map navigation). The same test was then repeated with eye open (actual navigation) and again with eye closed (mental navigation). Execution time was recorded in each test. Corsi block test and a psychiatric questionnaire completed the neuropsychological examination. RESULTS: Labyrinthine-defective patients showed higher levels of anxiety and depression and performed Corsi block test with more difficulties than controls. Patients spent more time than controls in the first and third session (eye closed). No difference was recorded between clockwise and counter-clockwise navigation tasks both in patients and in controls. Patients showed a greater improvement in the third navigation task than controls. CONCLUSION: Walking on memorized routes in non-visual condition is impaired by a peripheral vestibular damage, even if patients are well compensated. This impairment could be due to a defect of the visuospatial short-term memory, as supported by Corsi block tests, but a residual sensorimotor impairment and/or an interference of psychological distress could not be definitively exclude
Head shaking test and low-frequency rotation-acceleration test: comparison of sensitivity and specificity
No full textIn studying the vestibular-oculomotor reflex (VOR) in patients with equilibrium disorders, both active and passive methods are used and at different stimulation frequencies, particularly to evaluate vestibular compensation. The present study compares the sensitivity and specificity of the low-frequency pendular test and the HST in normal subjects and in subjects suffering from various vestibular pathologies but showing no signs of spontaneous nystagmus, even under optimal evaluation conditions (infrared videonystagmoscopy). These spontaneous nystagmus-free subjects underwent a routine study including: case history, infrared videonystagmoscopy (HST with 2 Hz stimulation) and ENG recording (saccadic movement, smooth pursuit, OKN, VOR, VOR-fix during pendular stimulation at 0.05 Hz and VOR after Fitzgerald-Hallpike heat stimulation). On the basis of the results the subjects were classified as follows: normal (N): case history free of any equilibrium disorders and all tests negative (122 cases; 8.1%); peripheral vestibular pathology (P): case history of equilibrium disorders and labyrinthine predominance (LP) in excess of 20% upon caloric testing (716 cases; 47.6%); central pathology (C): case history of equilibrium disorders and at least 3 pathological results from among the following tests: saccadic movement, smooth pursuit, OKN, VOR-fix (226 cases; 15.0%); mixed pathology (M): with both signs of P and C (440 cases; 29.3%). The pendular test showed signs of directional dominance (DP) higher than 10% (normal limit) in 7 cases of N (5.7%), 308 P (43.0%), 33 C (14.6%) and 162 M (36.8%). DP was higher than 10% in 55.2% of the P and M cases with onset less than 1 month before, in 42.8% of those with onset within the year and in 37.2% of those with onset more than a year before. A pathological response to the HST was observed (characterized by a series of at least 3 nystagmus shakes after a maximum latency of 15 seconds) in 0 N (0.0%), 378 P (52.8%), 4 C (1.8%) and 247 M (56.1%). The nystagmus seen was nearly always monophasic (92.5%), biphasic nystagmus was only seen in only a few cases (7.5%); moreover it was predominantly horizontal in nature (94.9%) while it was vertical in only a few of the C cases (5.1%). The HST proved pathological in 46.5% of those pathologies with onset less than 1 month before, in 55.8% of those with onset within the year and in 54.4% of those with onset more than a year before. In 213 of the cases presenting pathological response to the HST there was agreement between VOR DP at the pendular test and the direction of the nystagmus evoked by the HST: 138 P (74.6%), 0 C (0.0%), 75 M (68.2%): moreover there was no agreement in 83 cases. When the DP was lower than 10% at the pendular test, the HST proved pathological in 213 P (52.2%), 3 C (1.6%), 150 M (53.9%). Both tests gave negative results in 112 N (91.8%), 163 P (22.8%), 186 C (82.3%), 123 M (27.9%). In cases of peripheral vestibular deficit (P and M) the sensitivity of the rotoacceleration test was 40.7%, specificity 88.5%. The sensitivity of the HST was 54.1%, specificity 98.8%. The sensitivity of the association using both tests was 75.2%, specificity 85.7%
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
Improvement of Swallowing Function After Surgical Treatment of Diffuse Idiopathic Skeletal Hyperostosis: Our Experience
No full textObjective: To investigate the swallowing improvement in patients who underwent a transcervical prevascular retrovisceral approach for symptomatic cervical diffuse idiopathic skeletal hyperostosis (DISH), by means of the 10-item Eating Assessment Tool (EAT-10) questionnaire. Methods: Retrospective observational study of 21 patients treated with a transcervical anterior prevascular retrovisceral approach for symptomatic DISH with dysphagia as the primary symptom. All patients underwent videofluoroscopic study of swallowing before surgery and the EAT-10 questionnaire before and after the surgical procedure. Results: A statistically significant (P < 0.001) improvement in the postoperative EAT-10 score was reported. Sixteen out of 21 patients (76.2%) had their symptoms completely resolved, with an EAT-10 score less than 3. These results were not influenced by age and sex nor by presence of tracheostomy. The preoperative EAT-10 score was consistently related to postoperative outcome. Patients with mild and moderate dysphagia had better Δ in EAT-10 scores than patients with severe and very severe dysphagia (P = 0.02). Conclusions: Surgical management seems to be effective in resolving swallowing disorders related to this disease in a consistent percentage of patients. This evidence is supported by the statistically significant improvement in EAT-10 scores after treatment. Moreover, it might be postulated that early intervention can guarantee a higher success rate because patients with severe and very severe dysphagia had significantly smaller improvement
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