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21.
22.

Objectives/Hypothesis.

To determine whether respiratory compromise from bilateral vocal fold impairment (paralysis) can be objectively alleviated by reinnervation and pacing.

Methods.

A patient with paramedian vocal folds and synkinesis had a tracheotomy for stridor after bilateral laryngeal nerve injury and Miller Fisher syndrome. One posterior cricoarytenoideus (PCA) received a nerve‐muscle pedicle fitted with a perineural electrode for pacemaker stimulation. The airway was evaluated endoscopically and by spirometry for up to 1 year.

Results.

Bilateral vocal fold patency during quiet breathing was reversed to active vocal fold adduction during tracheal occlusion. Peak inspiratory flows (PIFs) were significantly higher (P < .001) after reinnervation. PIFs and glottic apertures increased further under stimulation (42 Hz, 1–4 mA, 42–400 μsec). although the differences were not significant.

Conclusions.

Based on our preliminary data, PCA reinnervation and pacing offer promise for amelioration of respiratory compromise after paradoxical adduction in bilateral vocal fold impairment. Laryngoscope, 2010  相似文献   
23.
Background: The long-QT syndromes (LQTS) are inherited electrical cardiomyopathies characterized by prolonged ventricular repolarization and ventricular arrhythmias. Several genetic reports have associated defects in LQTS-causing genes with atrial fibrillation (AF). We therefore studied whether atrial arrhythmias occur in patients with LQTS under daily-life conditions.
Methods: We systematically assessed atrial arrhythmias in LQTS patients and matched controls using implanted defibrillators or pacemakers as monitors of atrial rhythm in a nested case-control study. Twenty-one LQTS patients (3 male; 39 ± 18 years old; 18 on β blocker, ICD therapy duration 6.3 ± 2.7 years; 4 LQT1, 6 LQT2, 2 LQT3) were matched to 21 control subjects (13 male; 50 ± 19 years old; 3 on β blocker; pacemaker therapy duration 8.5 ± 5.5 years; 19 higher-degree AV block, 2 others). LQTS patients were identified by a systematic search of the LQTS patient databases in Münster and Munich.
Results: One-third (7 of 21) of the LQTS patients developed self-terminating atrial arrhythmias (atrial cycle lengths <250 ms). Only one control patient developed a single episode of postoperative AF (P < 0.05 vs LQTS).
Conclusions: LQTS patients at high risk for ventricular arrhythmias may develop short-lasting atrial arrhythmias under daily-life conditions, suggesting that prolonged atrial repolarization may contribute to the initiation of AF.  相似文献   
24.
25.
The dynamic signal intensity changes at magnetic resonance (MR) imaging in active and chronic wallerian degeneration in the corticospinal tract were evaluated. Forty-three patients with wallerian degeneration seen on MR images after cerebral infarction were studied. When possible, patients with acute stroke were examined with MR imaging prospectively at the onset of symptoms and then at weekly intervals for several months. Focal infarction without distal axonal degeneration is demonstrated for the 1st month following onset of clinical symptoms. At 4 weeks, a well-defined band of hypointense signal appears on T2-weighted images in the topographic distribution of the corticospinal tract. After 10-14 weeks, the signal becomes permanently hyperintense. Over several years, accompanying ipsilateral brain stem shrinkage occurs. The dark signal intensity observed on T2-weighted images between 4 and 14 weeks is believed to result primarily from transitory increased lipid-protein ratio.  相似文献   
26.
Changes in apolipoprotein and lipids in patients after surgery   总被引:1,自引:0,他引:1  
Plasma levels of apoproteins A-I, A-II and B and apoprotein/lipid ratios were determined in 43 patients (14 male and 29 female) on the second to the sixth day after gastrointestinal surgery. During this period, all the patients received i. v. 5% dextrose solutions only. Apoprotein levels (A-I, A-II and B), total cholesterol, HDL-cholesterol and phospholipid were significantly decreased after surgery but there was no sex differences. Patients undergoing major surgery showed much lower values than the ones undergoing minor surgery. Both the extent of the trauma and the caloric restriction resulting from sole carbohydrate intravenous feeding may be responsible for these changes. Decreased hepatic synthesis combined to a lack of intestinal supply might result in apo A-I and A-II reduction. Repeated determinations of apoprotein levels are proposed as simple means of follow-up for evaluating the degree of recovery of patients undergoing gastrointestinal surgery.  相似文献   
27.
To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation.  相似文献   
28.
Behind the multiple arguments for and against the use of premedication, sedative drugs in children is a noble principle that of minimizing psychological trauma related to anesthesia and surgery. However, several confounding factors make it very difficult to reach didactic evidence-based conclusions. One of the key confounding issues is that the nature of expectations and responses for both parent and child vary greatly in different environments around the world. Studies applicable to one culture and to one hospital system (albeit multicultural) may not apply elsewhere. Moreover, the study of hospital-related distress begins at the start of the patient's journey and ends long after hospital discharge; it cannot be focused completely on just the moment of anesthetic induction. Taking an example from actual practice experience, the trauma caused by the actual giving of a premedication to a child who absolutely does not want it and may struggle may not be recorded in a study but could form a significant component of overall effect and later psychological pathology. Clearly, attitudes by health professionals and parents to the practice of routine pediatric premedication, vary considerably, often provoking strong opinions. In this pro–con article we highlight two very different approaches to premedication. It is hoped that this helps the reader to critically re-evaluate a practice, which was universal historically and now in many centers is more selective.  相似文献   
29.
30.
Stage T1 glottic carcinoma: results of radiation therapy or laser excision   总被引:1,自引:0,他引:1  
Epstein  BE; Lee  DJ; Kashima  H; Johns  ME 《Radiology》1990,175(2):567-570
A retrospective analysis was made of the data on 60 patients with stage T1 glottic carcinoma (43 T1a, 17 T1b) who received radiation therapy and 17 patients with T1a disease who underwent laser excision as the primary treatment modality. Patients who received radiation therapy achieved 3- and 5-year actuarial local control rates of 92% and 89% for T1a and 77% and 77% for T1b disease, respectively. In patients who underwent laser excision (all with T1a disease), the 3-year local control rate was 77%. Of the 42 evaluable irradiated T1a patients, 31 (74%) had a normal to near-normal voice, eight (19%) had mild or intermittent hoarseness, and three (7%) had persistent hoarseness. Of the 13 evaluable patients in the laser-excision group, four (31%) had a normal to near-normal voice, five (38%) had mild or intermittent hoarseness, and four (31%) had persistent hoarseness. The difference in the quality of voice between these two groups is statistically significant (P = .012), although the ultimate local control rate after salvage therapy for irradiated patients (97%) was similar to that for laser-excision patients (94%).  相似文献   
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