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101.
Modal and falsetto registers are the basic vocal qualities used in female speaking voices. The purpose of this study was to identify the frequency at which modal register changed to falsetto register and the frequency range of each modal and falsetto register produced under three loudness levels: soft, comfortable and loud phonations in normal and dysphonic speakers. These data provide information on the relationship between vocal registers. It is hypothesized that vocal pathologies affect the frequency at which register change from one mode to another mode. Fifteen dysphonic and 15 non-dysphonic females were assessed on their ability to produce tone series from the lowest to the highest frequency at soft, comfortable and loud phonations. Fourteen listeners served as judges to identify the first production of falsetto voice in each tone series. The first falsetto tone perceived was considered to represent the frequency at which the modal-falsetto register change occurred perceptually. The change from modal to falsetto register in the tone series occurred between G4 (360.74 Hz) and B4 (485.23 Hz) in the dysphonic group and between A4 (421.00 Hz) and B4 (476.13 Hz) in the non-dysphonic group among the three loudness levels. The results showed that the presence of dysphonia affected the production of vocal registers The dysphonic group demonstrated the modal-falsetto register change at a significantly lower frequency and reduced frequency range in the modal register than those of the non-dysphonic group in the soft and comfortable phonations. In producing falsetto register, the dysphonic group demonstrated reduced ability in producing falsetto register in soft and loud phonations when compared to the non-dysphonic group. Physiological explanations are used to account for the observations. 相似文献
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Rodríguez L Starke H Guardia NM Tönnies H Neitzel H Kozlowski P Mazauric ML Heller A Grondona FL Mansilla E Santos Muñoz MJ Liehr T Martínez-Frías ML 《Clinical dysmorphology》2005,14(4):169-175
We report on three cases with a cytogenetically identical ring chromosome containing euchromatin from the long arm of chromosome 1 (r[1][::p11.1-->q21.1::]). Two cases were newborn males (Cases 1 and 2) and the third one was prenatally identified as female (Case 3). Mosaicism was present in all three cases in different degrees, i.e. 48%, 25% and 14% of the cells, respectively. Clinical signs and symptoms vary between the three cases.The results of our three cases are compared with those from the literature. 相似文献
105.
Wang ML Wu ZE Du QG Petsonk EL Peng KL Li YD Li SK Han GH Atffield MD 《Occupational and environmental medicine》2005,62(11):800-805
Aims: To investigate the early pattern of longitudinal change in forced expiratory volume in 1 second (FEV1) among new Chinese coal miners, and the relation between coal mine dust exposure and the decline of lung function. Methods: The early pattern of lung function changes in 317 newly hired Chinese underground coal miners was compared to 132 referents. This three year prospective cohort study involved a pre-employment and 15 follow up health surveys, including a questionnaire and spirometry tests. Twice a month, total and respirable dust area sampling was done. The authors used a two stage analysis and a linear mixed effects model approach to analyse the longitudinal spirometry data, and to investigate the changes in FEV1 over time, controlling for age, height, pack years of smoking, mean respirable dust concentration, the room temperature during testing, and the groupxtime interaction terms. Results: FEV1 change over time in new miners is non-linear. New miners experience initial rapid FEV1 declines, primarily during the first year of mining, little change during the second year, and partial recovery during the third year. Both linear and quadratic time trends in FEV1 change are highly significant. Smoking miners lost more FEV1 than non-smokers. Referents, all age less than 20 years, showed continued lung growth, whereas the miners who were under age 20 exhibited a decline in FEV1. Conclusion: Dust and smoking affect lung function in young, newly hired Chinese coal miners. FEV1 change over the first three years of employment is non-linear. The findings have implications for both methods and interpretation of medical screening in coal mining and other dusty work: during the first several years of employment more frequent testing may be desirable, and caution is required in interpreting early FEV1 declines. 相似文献
106.
Arola H Pitkänen M Nygård CH Huhtala H Manka ML 《Occupational medicine (Oxford, England)》2003,53(3):229-230
METHODS: The relationship between sickness absence and job control among industrial food workers of different ages (n = 114) was studied. RESULTS: The number of absence spells, particularly short absence spells, was higher among younger workers, as expected. Using multivariate analysis, low job control was associated with an increased number of all absence spells (P < 0.02). CONCLUSIONS: Job control may be an important factor in determining sickness absence among industrial workers. 相似文献
107.
Onning G Berggren A Drevelius M Jeppsson B Lindberg AM Johansson Hagslätt ML 《International journal of food sciences and nutrition》2003,54(4):281-289
The aim of the study was to investigate whether a supplement of antioxidants to subjects with a high working pace can influence the antioxidant capacity. The study was parallel and double blind with 98 subjects randomised into two groups. One of the groups was given a test drink with antioxidants for 4 weeks (450 ml/day) while the other group took a corresponding amount of placebo drink. The test drink contained: 2 mg beta-carotene/100 ml, 40 mg alpha-tocopherol/100 ml, 80 mg ascorbic acid/100 ml, 2 mg pyridoxine/100 ml, 15 mg magnesium/100 ml, 0.2 mg manganese/100 ml, 1 mg zinc/100 ml, 0.1 mg copper/100 ml and 10 microg selenium/100 ml. Consumption of the test drink for 4 weeks increased the total plasma antioxidant capacity by 7% (ferric reducing ability of plasma method, P<0.05 compared with the placebo group), and the content of selenium and selenoprotein P in serum was raised by 16-17% (P<0.001 compared with the placebo group). No significant changes were found in the placebo group. The test drink also contained Lactobacillus plantarum 299v (5 x 10(7) cfu/ml) and 4 weeks' consumption led to a significant increase of Lb. plantarum 299v in the faeces. In conclusion, consumption of a drink rich in different antioxidants can increase the antioxidant capacity in subjects with a high working pace. This can be valuable since it may increase the protection against reactive oxygen radicals. 相似文献
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Guild SJ Ward ML Cooper PJ Hanley PJ Loiselle DS 《Clinical and experimental pharmacology & physiology》2003,30(1-2):103-109
1. The method of action of cardiac glycosides is commonly explained by the 'pump-inhibition hypothesis': inhibition of the Na+/K+-ATPase allows [Na+]i to rise, eventually reversing Na+/Ca2+ exchange. The resulting influx of Ca2+o increases [Ca2+]i, thereby activating intracellular Ca2+-dependent ATPases and, hence, energy demand. This sequence has been presumed to occur during diastole as well as systole. However, it has been reported that dihydro-ouabain-induced potentiation of heat production by quiescent ventricular trabeculae persists in the absence of Ca2+o. This implies that the pump-inhibition hypothesis is inapplicable during diastole. 2. We tested this implication by: (i). measuring the rate of oxygen consumption (Vo2) of arrested guinea-pig whole-hearts; (ii). measuring[Ca2+]i in quiescent ventricular trabeculae; and (iii). mathematical modelling using software (Oxsoft Heart, Oxford Software, Oxford, UK) based on DiFrancesco-Noble formalism. 3. Upon induction of arrest, whole heart Vo2 fell to one-quarter of its 'beating' value. Subsequent perfusion with ouabain (20 micromol/L), in the presence of Ca2+o, increased Vo2 fourfold. This increase was prevented by withholding Ca2+o. Comparable results were obtained in quiescent trabeculae: ouabain increased [Ca2+]i only if Ca2+o was present. Mathematical modelling readily simulated these experimental results. 4. We conclude that influx of Ca2+o is mandatory for potentiation of cardiac basal metabolism by cardiac glycosides. 相似文献