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151.
Diffusion‐weighted quantitative MRI to diagnose benign conditions from malignancies of the anterior mediastinum: Improvement of diagnostic accuracy by comparing perfusion‐free to perfusion‐sensitive measurements of the apparent diffusion coefficient 下载免费PDF全文
152.
Massimiliano Garzaro Giancarlo Pecorari MD Vincenzo Landolfo MD Simona Defilippi MD Carlo Giordano MD 《Otolaryngology--head and neck surgery》2010,143(3):348-352
Objective
The aim of this study was to assess the outcomes after radiofrequency inferior turbinate reduction (RITR) on objective and subjective nasal function in patients with nasal obstruction caused by turbinate hypertrophy and to evaluate the possible effect on olfactory function.Study Design
Case series with planned data collection.Setting
ENT division, university hospital.Subjects and Methods
Forty consecutive patients who underwent RITR for allergic or nonallergic chronic rhinitis with inferior turbinate hypertrophy were tested before and two months after the surgical procedure, using the Sniffin' Sticks test battery, anterior rhinomanometry, and the nasal obstruction symptom evaluation (NOSE) scale.Results
The total basal nasal resistance at 150 Pa diminished significantly two months after surgery. Preoperative olfactory tests showed anosmia in five percent (n = 2) of the patients, hyposmia in 82 percent (n = 33), and normosmia in 12 percent (n = 5). At two months from the intervention, two percent (n = 1) were diagnosed as anosmic, 12 percent (n = 5) as hyposmic, and 85 percent (n = 34) as normosmic. The means of preoperative odor threshold (T), discrimination (D), identification (I), and the overall TDI score improved significantly postoperatively (P < 0.001). The NOSE score in the two-month follow-up improved in 97.5 percent (n = 39) of patients, with a mean difference in pre- vs. postintervention score of 40.12 (95% confidence interval 35.75-44.25; P < 0.001).Conclusion
RITR may provide excellent outcomes in terms of improvement in olfactory function and nasal flow in patients affected by turbinate hypertrophy refractory to medical therapy. 相似文献153.
Pecori Giraldi F Andrioli M De Marinis L Bianchi A Giampietro A De Martin M Sacco E Scacchi M Pontecorvi A Cavagnini F 《European journal of endocrinology / European Federation of Endocrine Societies》2007,156(2):233-239
OBJECTIVE: Impaired GH secretion usually accompanies Cushing's syndrome and a variable proportion of patients reportedly fail to recover normal GH secretion after successful treatment. This wide variability is most probably due to differences in the treatment (i.e. surgery and/or radiotherapy), timing of patient re-evaluation after surgery and dynamic tests employed to challenge GH secretion, and hinders a precise assessment of risk of GH deficiency after cure. The aim of the present study is to evaluate GH secretory status after long-term cure of Cushing's disease achieved by surgery alone. DESIGN AND METHODS: We studied 34 patients (27 females and 7 males, age range 21-68 years) formerly affected by Cushing's disease. Patients were studied 2-20 years (median 3.3 years) following remission of hypercortisolism; all patients underwent transsphenoidal surgery with the removal of an ACTH-secreting adenoma; repeat pituitary surgery for relapse was performed in two patients while bilateral adrenalectomy was necessary in two patients. In all subjects, the GH response to GHRH+arginine stimulation was evaluated. At the time of testing, 13 patients were still on steroid replacement therapy. RESULTS: In long-term surgical remission, 22 patients (65.0%) presented subnormal GH secretion; partial GH deficiency (GH peak <16.5 microg/l) was found in 11 patients and severe GH deficiency (GH peak <9 microg/l) in another 11. Male gender and length of hypercortisolism were risk factors for postsurgical GH deficiency. CONCLUSIONS: This study demonstrates the presence of GH deficiency in a high percentage of patients with Cushing's disease after long-term remission of hypercortisolism obtained by surgery alone. Male gender and length of hypercortisolism are the most significant predictors of postsurgical GH deficiency. This finding is significant as it highlights that even the most favourable therapeutical course, i.e. remission achieved by surgery alone, is accompanied by impaired GH secretion. Assessment of GH secretion is therefore recommended for all patients cured from Cushing's disease, even if not submitted to radiotherapy. Studies on the clinical impact of GH deficiency and the use of GH replacement therapy seem warranted in patients cured from Cushing's disease. 相似文献
154.
Loreno M Bucceri AM Catalano F Muratore LA Blasi A Brogna A 《Digestive diseases and sciences》2004,49(3):404-407
We assessed the ultrasonographic pattern of gastric emptying in patients with functional dyspepsia, evaluating its relationship with symptoms. Twenty dyspeptic patients, with slight (group A) and severe (group B) symptoms, and 10 controls (group C) underwent ultrasonographic study of gastric emptying by measuring postprandial variations of the antral area at regular intervals. The time at which the antral area returned to the basal value was assumed to be the final emptying time. The final emptying time was significantly longer in both group A (294 +/- 42 min) and group B (340 +/- 36 min) compared to controls (244 +/- 21 min), but no significant difference was observed between them. A significantly (P < 0.05) greater dilation of the antral area was found at 50 min in group B compared to group A patients. A different pattern of antral motor function rather than a delay of gastric emptying correlates with the severity of symtoms in dyspeptic patients. 相似文献
155.
156.
Convergent findings demonstrate that numbers can be represented according to a spatially oriented mental number line. However, it is not established whether a default organization of the mental number line exists (i.e., a left-to-right orientation) or whether its spatial arrangement is only the epiphenomenon of specific task requirements. To address this issue we performed two experiments in which subjects were required to judge laterality of hand stimuli preceded by small, medium or large numerical cues; hand stimuli were compatible with egocentric or allocentric perspectives. We found evidence of a left-to-right number–hand association in processing stimuli compatible with an egocentric perspective, whereas the reverse mapping was found with hands compatible with an allocentric perspective. These findings demonstrate that the basic left-to-right arrangement of the mental number line is defined with respect to the body-centred egocentric reference frame. 相似文献
157.
Andrea Cavagna Alessio Cimarelli Irene Giardina Giorgio Parisi Raffaele Santagati Fabio Stefanini Massimiliano Viale 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(26):11865-11870
From bird flocks to fish schools, animal groups often seem to react to environmental perturbations as if of one mind. Most studies in collective animal behavior have aimed to understand how a globally ordered state may emerge from simple behavioral rules. Less effort has been devoted to understanding the origin of collective response, namely the way the group as a whole reacts to its environment. Yet, in the presence of strong predatory pressure on the group, collective response may yield a significant adaptive advantage. Here we suggest that collective response in animal groups may be achieved through scale-free behavioral correlations. By reconstructing the 3D position and velocity of individual birds in large flocks of starlings, we measured to what extent the velocity fluctuations of different birds are correlated to each other. We found that the range of such spatial correlation does not have a constant value, but it scales with the linear size of the flock. This result indicates that behavioral correlations are scale free: The change in the behavioral state of one animal affects and is affected by that of all other animals in the group, no matter how large the group is. Scale-free correlations provide each animal with an effective perception range much larger than the direct interindividual interaction range, thus enhancing global response to perturbations. Our results suggest that flocks behave as critical systems, poised to respond maximally to environmental perturbations. 相似文献
158.
159.