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51.
Postpoliomyelitis syndrome (PPS) is a disease that may occur in survivors of acute poliomyelitis several decades after their initial infection. It can present as dysphonia, with vocal weakness and fatigue. Swallowing, respiratory, and other laryngopharyngeal symptoms may be manifestations of the disease or they may represent worsening of previously stable and compensated deficits. Three cases of laryngeal changes in PPS with videostroboscopic and laryngeal electromyography findings highlight the features of this disorder. We review possible etiologies of laryngeal PPS, diagnostic criteria, and treatment, as well as the current literature.  相似文献   
52.
Cricothyroid joint injuries may result in severe voice dysfunction and may be associated with laryngeal pain. Otolaryngologists and radiologists should be familiar with this rarely recognized injury.  相似文献   
53.
Arts medicine is a new, rapidly developing discipline that includes voice, hand, dance, and other subspecialty areas. At present, there is no organized academic arts medicine tradition. Therefore, it is difficult for interested persons to obtain convenient, high-quality education designed for the special needs of arts medicine practitioners. To meet this need, development of a Ph.D. program in arts medicine appears to be desirable. The structure of such a program is proposed, along with specific requirements for a Ph.D. in arts medicine with a concentration in voice.  相似文献   
54.
Young adulthood is notable for rapid physical changes and psychosocial instability. Care of the young adult professional voice requires knowledge of the specific anatomic and physiologic changes associated with the mutational voice, as well as the effects of general growth and maturation on the vocal mechanism. The effects of psychological stresses common to young adulthood, such as educational commitments and early career choices, must also be understood. Upper respiratory infection and allergies are common in this age group. Treatment of these conditions must be tailored in the professional voice user because of the potential side effects of some medications and the performance imperatives of the patient. Surgical indications for tonsillectomy in the young voice patient are discussed. There are no special considerations in the evaluation and treatment of laryngeal pathology in the young adult, with the exception of limiting the use of sedative anesthesia. However, conservatism in surgical decision-making is advised. The development of a stable, efficient vocal technique and a mature professional background requires time, patience, and hard work.  相似文献   
55.
Brass (a zinc/copper alloy) foil reacts with mixtures of water and alkyl bromides to give dissolution of zinc and copper. The relative rates of leaching depend on the bromide used: saturated bromides favor dissolution of zinc, whereas unsaturated bromides favor dissolution of copper. This difference is attributed to the formation of π-complexes between the unsaturated linkages and the copper atoms.  相似文献   
56.
Synthetic oligonucleotides (ONs) are often prepared for development of therapeutic candidates. Among the modifications most often incorporated into therapeutic ONs are phosphorothioate (PT) linkages. The PT linkage introduces an additional chiral center at phosphorus to the chiral centers in D-ribose (and 2-deoxy-D-ribose) of the nucleic acid. Therefore, modified linkages can produce a diastereoisomer pair ([Rp] and [Sp]) at each PT linkage. These isomers are of identical length, sequence, charge and mass, and are not reliably separated by most chromatographic approaches (e.g., reversed phase chromatography) unless the ON is very short. Further these isomers are not distinguishable by single-stage mass spectrometry. During chromatography of a purified anti-NGF (nerve growth factor) aptamer containing 37 bases with 2 PT linkages by monolithic pellicular anion-exchange (pAE) column, we observed four components. The four components were postulated to be: (i) distinct folding conformations; (ii) fully and partially athioated aptamers; or (iii) PT diastereoisomers. Fractionation of the components, followed by de- and re-naturation failed to produce the original forms by refolding, eliminating option (i). Mass spectrometry of the fractionated, desalted samples revealed no significant mass differences, eliminating option (ii). Oxidative conversion of the PT to phosphodiester (PO) linkages in each of the purified components produced a single chromatographic peak, co-eluting with authentic PO aptamer, and having the PO aptamer mass. We conclude that the components resolved by pAE chromatography are diastereoisomers arising from the two PT linkages. Hence, pAE chromatography further enhances characterization of ON therapeutics harboring limited PT linkages and having up to 37 bases.  相似文献   
57.
58.
A new RFQ ion-beam cooler and buncher, installed after the mass-separating magnet of the ion guide isotope separator, IGISOL, JYFL, has dramatically increased the scope of on-line laser spectroscopy at this facility. The device, operated in a bunching mode, has permitted new measurements on short-lived radionuclei in the Ti, Zr and Hf chains at a sensitivity two orders of magnitude greater than that previously achieved. The device has also opened new prospects for laser-based nuclear spectroscopy at the facility, particularly collinear resonance ionisation spectroscopy. Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002 RID="a" ID="a"e-mail: pc@mags.ph.man.ac.uk  相似文献   
59.
We determine the weak coupling /V(cb)/ between the b and c quarks using a sample of 3 x 10(6) BB; events in the CLEO detector at the Cornell Electron Storage Ring. We determine the yield of reconstructed B-->D*l nu; decays as a function of w, the boost of the D* in the B rest frame, and from this we obtain the differential decay rate d Gamma/dw. By extrapolating d Gamma/dw to w=1, the kinematic end point at which the D* is at rest relative to the B, we extract the product /V(cb)/F(1), where F(1) is the form factor at w=1. Combined with theoretical results for F(1) we determine /V(cb)/=0.0469+/-0.0014(stat)+/-0.0020(syst)+/-0.0018(theor).  相似文献   
60.
Respiratory and glottal efficiency measures were collected from a pool of 40 classically trained singers with normal larynges. All singers had ?3 years of formal classical voice training and were active professional solo classical singers. Mean flow rates were obtained from all subjects to assess glottal efficiency. Additionally, maximum phonation times and phonation quotients were obtained from a subset of the singers. Pulmonary function test data on forced expiratory volume, forced vital capacity, and forced expiratory flow were obtained for all subjects. Results were compared with published normal values, not specifically derived from trained singers, used commonly in voice laboratoires. Differences were found, suggesting the need for separate normative data to be used for evaluation of the vocal athlete.  相似文献   
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