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排序方式: 共有395条查询结果,搜索用时 9 毫秒
31.
Marya Sheikh Rashid Wouter A. Dreschler Jan A. P. M. de Laat 《International journal of audiology》2017,56(12):967-975
Objective: To evaluate a Dutch online speech-in-noise screening test (in Dutch: “Kinderhoortest”) in normal-hearing school-age children. Sub-aims were to study test–retest reliability, and the effects of presentation type and age on test results. Design: An observational cross-sectional study at school. Speech reception thresholds (SRTs) were obtained through the online test in a training condition, and two test conditions: on a desktop computer and smartphone. The order of the test conditions was counterbalanced. Study sample: Ninety-four children participated (5–12 years), of which 75 children were normal-hearing (≤25?dB HL at 0.5?kHz,?≤20?dB HL at 1–4?kHz). Results: There was a significant effect for test order for the two test conditions (first or second test), but not for presentation type (desktop computer or smartphone) (repeated measures analyses, F(1,75)?=?12.48, p?0.001; F(1,75)?=?0.01, p?=?0.982). SRT significantly improved by age year (first test: 0.25?dB SNR, 95% CI: –0.43 to –0.08, p?=?0.004. Second test: 0.29?dB SNR, 95% CI: –0.46 to –0.11; p?=?0.002). Conclusions: The online test shows potential for routine-hearing screening of school-age children, and can be presented on either a desktop computer or smartphone. The test should be evaluated further in order to establish sensitivity and specificity for hearing loss in children. 相似文献
32.
Neil B. Marya Patrick D. Powers Larissa Fujii-Lau Barham K. Abu Dayyeh Ferga C. Gleeson Shigao Chen Zaiyang Long David M. Hough Vinay Chandrasekhara Prasad G. Iyer Elizabeth Rajan William Sanchez Tarek Sawas Andrew C. Storm Kenneth K. Wang Michael J. Levy 《Gastrointestinal endoscopy》2021,93(5):1121-1130.e1
33.
R K Marya S Sood H Lal A Sharma A S Saini 《Indian journal of physiology and pharmacology》1988,32(2):126-131
Plasma cortisol and urinary excretion of water, sodium, potassium, calcium and magnesium have been studied in the rat after application of heat stress. There was a significant increase in plasma cortisol level after exposure to heat. During heat stress complete cessation of urine formation was observed. In the next 30 min there was statistically significant increase in the urinary excretion of water, sodium and calcium but not of potassium and magnesium. Urinary calcium/magnesium ratio was also significantly elevated. The increase in urinary water and electrolyte excretion seemed to be mediated through prostaglandins since it could be abolished by administration of indomethacin prior to the application of heat stress. On the basis of these results, the possible role of heat stress in the genesis of urolithiasis has been discussed. 相似文献
34.
Two prohormones for gastrin-releasing peptide are encoded by two mRNAs differing by 19 nucleotides. 总被引:5,自引:3,他引:2
E R Spindel M D Zilberberg J F Habener W W Chin 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(1):19-23
In our studies on the molecular biology of human gastrin-releasing peptide (GRP), we have discovered an example of a change in translational reading frame apparently produced through alternative RNA splicing. Complementary DNAs prepared from a pulmonary carcinoid tumor rich in GRP immunoreactivity had one of two different-sized internal DNA fragments after digestion with the restriction enzyme Pvu II. Nucleotide sequences of the two DNA fragments were identical except for 19 additional nucleotides present in the larger fragment. The region of the mRNA containing the 19 nucleotides corresponded to the carboxyl-terminal region of the human GRP precursor. The resulting shift in reading frame causes a difference of 10 amino acids in size and an overall sequence difference of 27 amino acids between the two GRP prohormones so formed. The change in reading frame described here is unusual in eukaryotes and is yet another mechanism to produce diversity in the generation of biological peptides. 相似文献
35.
Background
Adult patients on prolonged acute mechanical ventilation (PAMV) comprise 1/3 of all adult MV patients, consume 2/3 of hospital resources allocated to MV population, and are nearly twice as likely to require a discharge to a skilled nursing facility (SNF). Their numbers are projected to double by year 2020. To aid in planning for this growth, we projected their annualized days and costs of hospital use and SNF discharges in year 2020 in the US. 相似文献36.
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38.
Various pulmonary function tests, FVC, FEV1/FVC%, PEFR, EFR25-75, MVV and Tlco were measured in 25 asymptomatic male flour mill workers and 50 healthy subjects not working at flour mill, to assess the effect of flour dust on lungs. All the subjects of different groups were well matched in their anthropometeric parameters and socio economic status. In smoker flour mill workers significant reduction was present in both ventilatory and diffusion functions of lungs, which was more pronounced in subjects who consumed larger quantity of tobacco and were exposed to flour dust for longer duration. On the other hand deterioration of pulmonary functions in non smoker flour mill workers was found to be statistically not significant. The relative strength of both the parameters viz tobacco and flour dust for impairment of pulmonary functions is discussed for being a pointer to further studies. 相似文献
39.
Urinary calcium excretion and creatinine clearance studies have been conducted in 50 women at 36 weeks of pregnancy and 50 normal controls. Of the pregnant women, 25 had been administered 600,000 IU vitamin D in the 24-26 weeks of pregnancy (supplemented group). The non-supplemented group showed significant hypocalcaemia (even after accounting for low plasma protein levels) and hypocalciuria, while the supplemented group showed normocalcaemia as well as significantly greater 24-hour urinary calcium excretion than the controls. 24-hour creatinine clearance was increased in both groups of pregnant women. It was concluded that, due to increased GFR, urinary calcium excretion tends to increase in pregnancy provided the subject is not deficient in vitamin D. Occurrence of hypocalciuria in pregnancy suggests vitamin D deficiency and should not be considered a physiological adaptation. 相似文献
40.