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31.
OBJECTIVE: The aim of this study was to identify the effects of objective laryngopharyngeal reflux (LPR) on the acoustic parameters of patients by comparing their voice samples with that of control subjects. STUDY DESIGN: Prospective study in two tertiary reference hospitals. METHODS: 48 consecutive patients with symptoms related to LPR and 64 control subjects were included in the study. Suspected LPR patients underwent a 24-hour ambulatory pH monitoring, and 25 (52%) of them were shown to have objective LPR. Acoustical evaluation results of objective LPR patients were compared with that of symptomatic LPR patients and control subjects. RESULTS: All frequency perturbation values obtained from objective and symptomatic LPR patients were higher than the control subjects (P<0.01). Mean fundamental frequency, amplitude perturbation measures, and noise-to-harmonics ratio were not significantly different between groups. CONCLUSION: LPR patients have significantly different frequency perturbation values than control subjects.  相似文献   
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A hypophonic voice, characterized perceptually as weak and breathy, is associated with voice disorders such as vocal fold atrophy and unilateral vocal fold paralysis. Although voice therapy programs for hypophonia typically address the vocal folds or the sound source, twang voice quality was examined in this study as an alternative technique for increasing vocal power by altering the epilarynx or the sound filter. OBJECTIVE: This study investigated the effect of twang production on physiologic, acoustic, and perceived voice handicap measures in speakers with hypophonia. DESIGN/METHODS: This prospective pilot study compared the vocal outcomes of six participants with hypophonia at pre- and posttreatment time points. Outcome measures included mean airflow rate, intensity in dB sound pressure level (SPL), maximum phonation time, and self-report of voice handicap. RESULTS: All subjects improved in at least three of the four vocal outcome measures. Wilcoxon signed-rank test of paired differences revealed significant differences between pre- and posttherapy group means for airflow rate, SPL, and Voice Handicap Index scores. CONCLUSION: The twang voice quality as a manipulation of the sound filter offers a clinical complement to traditional voice therapies that primarily address the sound source.  相似文献   
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The objective of this study was to examine the vocal symptoms and acoustic changes perceived in the short period after endotracheal intubation, and to find the association between these changes and the endotracheal tube parameters. A total of 35 subjects were included. They were examined preoperatively, and 2 and 24 hours postoperatively. The vocal symptoms of hoarseness, vocal fatigue, loss of voice, throat clearing, globus pharyngeus, throat pain, and the acoustic variables mainly average fundamental frequency, relative average perturbation, shimmer, noise to harmony ratio, voice turbulence index, habitual pitch, and maximum phonation time (MPT) were assessed as such and in relation to the following endotracheal tube parameters: duration of anesthesia, number of intubation attempts, size of the tube, cuff volume, cuff mean pressure, and the emergence. The association between anesthesia parameters with incidence of vocal complaints and changes in acoustic parameters were examined using logistic and linear regression. Vocal fatigue was associated significantly with the increase in cuff volume and the number of intubation attempts. Throat clearing was associated significantly with the increase in cuff mean pressure. Only the increase in habitual pitch was associated significantly with the increase in cuff volume. The acute short-term effect of endotracheal intubation on voice is significant. The most important endotracheal tube parameters that affect the vocal changes are the cuff mean pressure and volume. The laryngeal contribution to these vocal changes seems to be minimal. All vocal symptoms increased significantly except for globus pharyngeus at 2 hours postoperatively. The acoustic parameters did not change significantly except for a decrease in MPT. At 24 hours postoperatively, all vocal symptoms subsided with no significant difference to baseline value. The habitual pitch increased significantly, and the rest of the parameters remained comparable to baseline value.  相似文献   
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Prader-Willi syndrome (PWS) is a multisystem disorder caused by DNA abnormalities involving chromosome 15. Major characteristics are infant hypotonia, hypogonadism, mental retardation, a short stature, atypical facial appearance, and the onset of obesity due to insatiable hunger in early childhood. Also, speech and language abnormalities have been reported including voice disorders. These have seldom been studied in detail, however. This paper reports the results of an acoustic and aerodynamic investigation of the voice in 22 individuals with PWS. Two age groups were distinguished, a group of children [chronological age (CA) 6 years, 7 months through 11 years, 7 months; total intelligence quotient (TIQ) 40-88] and a group of adolescents and adults (CA 17 years, 1 month through 29 years, 5 months; TIQ 41-94). Both aerodynamic and acoustic parameters were obtained and compared with normative data from the Belgian Study Group on Voice Disorders. It was found that voice difficulties do commonly occur in individuals with PWS including impairment of frequency levels, voice quality, and poor aerodynamic capabilities.  相似文献   
37.
The aim of this study was to investigate the prevalence of acid reflux in patients complaining of hoarseness where no organic disease or functional dysphonia could be found. We also aimed to determine whether anti-reflux treatment improved their symptoms. Patients were not selected on the basis of symptoms of reflux. Fifty patients with hoarseness took part in a prospective study that sought to establish objectively whether acid reflux was present. All patients were given a 6-week course of ranitidine and Gaviscon. Patients were asked to score their voice quality before and after treatment. Although 72% of patients complained of heartburn more than once a week, only 40% proved to have acid reflux. Although subjective improvement after anti-reflux treatment was found in a larger proportion of those with than without proven reflux, the conclusions that can be drawn are limited as there were no satisfactory objective measurements of voice or controls.  相似文献   
38.
The surgical management of bilateral vocal cord paralysis has been performed through an endoscope in the past. The etiology of bilateral vocal cord paralysis is usually secondary to trauma; to secure an adequate airway, a tracheostomy is performed. Endoscopic laser arytenoidectomy offers a safe method of decannulating patients with maintenance of good voice quality and a rima glottidis of 4–6 mm posteriorly. Several wavelengths are available to carry out this procedure, and this article will focus on Nd:Yag laser scalpel applications. The advantage of this method is the preservation of good voice quality with an option of an external procedure, if the need arises. The laser application offers excellent hemostasis, and decreased edema and scar tissue formation. The results of our study on 10 patients appear encouraging and superior with respect to other available wavelengths.  相似文献   
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Objectives

To ascertain whether cochlear implantation (CI), without specific vocal rehabilitation, is associated with changes in perceptual and acoustic vocal parameters in adults with severe to profound postlingual deafness.

Hypothesis

Merely restoring auditory feedback could allow the individual to make necessary adjustments in vocal pattern.

Study Design

Prospective and longitudinal.

Methods

The experimental group composed of 40 postlingually deaf adults (20 males and 20 females) with no previous laryngeal or voice disorders. Participants’ voices were recorded before CI and 6–9 months after CI. To check for chance modifications between two evaluations, a control group of 12 postlingually deaf adults, six male and six female, without CI was also evaluated. All sessions composed of the recording of read sentences from Consensus Auditory-Perceptual Evaluation of Voice and sustained vowel /a/. Auditory and acoustic analyses were then conducted.

Results

We found a statistically significant reduction in overall severity, strain, loudness, and instability in auditory analysis. In vocal acoustic analysis, we found statistically significant reduction fundamental frequency (F0) values (in male participants) and F0 variability (in both genders). The control group showed no statistically significant changes in most vocal parameters assessed, apart from pitch and F0 (in female participants only). On comparing the interval of variation of results between the experimental and control groups, we found no statistically significant difference in vocal parameters between CI recipients and nonrecipients, with the exception of F0 variability in male participants.

Conclusions

The patients in our sample showed changes in overall severity, strain, loudness, and instability values, and reductions in F0 and its variability. On comparing the variation of results between the groups, we were able to prove in our study that implant recipients postlingually deaf adults (experimental group), without specific vocal rehabilitation, differed from nonrecipients (control group) in loudness and F0 variability sustained vowel /a/ in male participants.  相似文献   
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