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1.
目的通过研究肺表面活性物质(PS)结合持续气道正压通气(CPAP)治疗新生儿呼吸窘迫综合征(NRDS)的治疗效果,进一步指导NRDS的临床治疗。方法选取于2017年4月-2018年10月间在本院收治的80例确诊为新生儿呼吸窘迫综合征的患儿作为研究对象,随机将患儿分为试验组和对照组,对照组给予持续气道正压通气治疗,试验组在对照组的基础上联合使用PS治疗。结果试验组对于呼吸窘迫缓解的有效率明显高于对照组,在气管插管内滴入PS治疗后试验组的血气情况明显优于对照组,且试验组患儿副作用发生率明显低于对照组,以上指标差异具有统计学意义,P <0.05。结论 PS结合CPAP在新生儿呼吸窘迫综合征的治疗中疗效很好。 相似文献
2.
Attila Szalmas Peter Bodrogi Cecilia Sik-Lanyi 《Ophthalmic & physiological optics》2006,26(3):281-287
The objective of this study is to test the luminous efficiency functions V(lambda), V'(lambda), V(10)(lambda) and their linear combinations on the basis of a data set gained from a simulated mesopic night-time driving experiment. Another aim is to provide 'real-world' data for the 'X framework' or 'linear combination model', and to find out its limits in a practical situation. Human performance was measured by the reaction time method. Results show that the single parameter of the linear combination of photopic and scotopic luminous efficiency functions can be determined analytically with little variation for a given mesopic background luminance level and a given visual target colour, but the computation leads to considerable deviations comparing all three target colours (red, green and blue) used in the experiment. The conclusion for the given experimental conditions is that the single parameter of the linear combination model has an increasing deviation for lower background luminance levels. 相似文献
3.
Selecting an appropriate working correlation structure is pertinent to clustered data analysis using generalized estimating equations (GEE) because an inappropriate choice will lead to inefficient parameter estimation. We investigate the well‐known criterion of QIC for selecting a working correlation structure, and have found that performance of the QIC is deteriorated by a term that is theoretically independent of the correlation structures but has to be estimated with an error. This leads us to propose a correlation information criterion (CIC) that substantially improves the QIC performance. Extensive simulation studies indicate that the CIC has remarkable improvement in selecting the correct correlation structures. We also illustrate our findings using a data set from the Madras Longitudinal Schizophrenia Study. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
4.
C. BOSCO A. ITO P. V. KOMI P. LUHTANEN P. RAHKILA H. RUSKO J. T. VIITASALO 《Acta physiologica (Oxford, England)》1982,114(4):543-550
The influence of prestretch amplitude on the mechanical efficiency was examined with 5 subjects, who performed 5 different series of vertical jumps, each of which differed with respect to the mechanics of the knee joint action during the prestretch (eccentric) phase of the contact on the floor. Electromyographic activity was recorded from the major extensor muscles during the entire work period of 1 min per series. In addition, expired air was collected during the test and recovery for determination of energy expenditure. Mechanical work was calculated from the vertical displacement of the body during the jumps. The results indicated that high net efficiency of 38.7% was observed in condition where amplitude of knee bending in eccentric phase was small. In large range motion the corresponding net efficiency was 30.1%. In jumps where no prestretching of extensor muscles ocurred the net efficiency was 19.7%. The high efficiency of small amplitude jumps was characterized by low myoelectrical activity of the leg extensor muscles during the positive (concentric) work phase. In addition, the small amplitude jumps had shorter transition time in the stretch-shortening cycle, high average eccentric force and high stretching speed. Therefore the results suggest that the restitution of elastic energy, which was also related to the length change and stiffness of the muscles during stretch, plays an important role in regulating the mechanical efficiency of work. 相似文献
5.
Mourot L Hintzy F Messonier L Zameziati K Belli A 《European journal of applied physiology》2004,93(3):325-332
This study proposed a non-invasive method to determine the gross (GE, no baseline correction), net (NE, resting metabolism as the baseline correction) and work (WE, unloaded cycling as the baseline correction) efficiencies during cycling at an intensity higher than the maximal aerobic power (MAP). Twelve male subjects performed two exercises consisting of 4 min at 50% MAP followed either by 8 min at 63% MAP or by 8 sequences of 60 s divided into 10 s at 130% MAP and 50 s at 50% MAP (i.e., 63% MAP on average). Oxygen uptake was continuously measured to calculate GE, NE and WE at 50%, 63% and 130% MAP, and the data presented as the means and standard deviations. The GE values were 18.2%, 19.1%, 22.7%, the NE values were 22.4%, 22.8%, 24.3% and the WE values were 34.2%, 31.4% and 27.2% at 50%, 63% and 130% MAP, respectively. The GE and NE increased (P<0.001) whereas the WE decreased (P<0.001) with each increment in power output. The GE was lower than the NE (P<0.001) at 50% and 63% MAP and than the WE (P<0.001) at all intensities. The NE was lower (P<0.001) than the WE at 50% and 63% MAP. These results showed that (1) efficiency index values obtained during supra-maximal exercise were consistent with previous proposals and (2) the efficiency-power output relationships were not limited to sub-maximal intensity levels but were confirmed at higher power output. 相似文献
6.
An energy balance of front crawl 总被引:1,自引:3,他引:1
Zamparo P Pendergast DR Mollendorf J Termin A Minetti AE 《European journal of applied physiology》2005,94(1-2):134-144
With the aim of computing a complete energy balance of front crawl, the energy cost per unit distance (C= v–1, where is the metabolic power and v is the speed) and the overall efficiency (o=Wtot/C, where Wtot is the mechanical work per unit distance) were calculated for subjects swimming with and without fins. In aquatic locomotion Wtot is given by the sum of: (1) Wint, the internal work, which was calculated from video analysis, (2) Wd, the work to overcome hydrodynamic resistance, which was calculated from measures of active drag, and (3) Wk, calculated from measures of Froude efficiency (F). In turn, F=Wd/(Wd+Wk) and was calculated by modelling the arm movement as that of a paddle wheel. When swimming at speeds from 1.0 to 1.4 m s–1, F is about 0.5, power to overcome water resistance (active body drag × v) and power to give water kinetic energy increase from 50 to 100 W, and internal mechanical power from 10 to 30 W. In the same range of speeds increases from 600 to 1,200 W and C from 600 to 800 J m–1. The use of fins decreases total mechanical power and C by the same amount (10–15%) so that o (overall efficiency) is the same when swimming with or without fins [0.20 (0.03)]. The values of o are higher than previously reported for the front crawl, essentially because of the larger values of Wtot calculated in this study. This is so because the contribution of Wint to Wtot was taken into account, and because F was computed by also taking into account the contribution of the legs to forward propulsion. 相似文献
7.
Fernando Santos James C. M. Chan James D. Hanna Kazuhiko Niimi Richard J. Krieg Jr Martha D. Wellons 《Pediatric nephrology (Berlin, Germany)》1992,6(3):262-266
To investigate the effects of growth hormone (GH) on the reversal of growth failure in uremia, recombinant human GH (rhGH) was administered to rats with chronic renal failure (CRF). The dosage of rhGH was 3 IU/day (i.p.) for 13 days after the induction of CRF by 5/6 nephrectomy. Animals were classified into four groups: untreated nephrectomized rats (NX,n=40), GH-treated nephrectomized rats (NX+GH,n=18), sham-operated rats fed ad libitum (SHAMAL,n=27), and sham-operated rats pair-fed with 10 NX rats (SHAMPF,n=10). NX and NX+GH rats developed a similar and moderate degree of CRF, serum urea nitrogen being (mean±SEM) 49±3 and 54±4 mg/dl, respectively, compared with 16±4 and 19±0 mg/dl in SHAMAL and SHAMPF groups. Weight (56.0±3.3 g) and length (3.5±0.1 cm) gains of NX rats were lower than those of SHAMAL rats (94.2±4.0 g,P<-0.0001 and 4.1±0.2 cm,P<-0.01). Growth of the SHAMPF group and the matched NX rats was not significantly different. Weight (56.2±5.0 g) and length (3.4±0.2 cm) gains of NX+GH and NX rats were similar, the beneficial effect of GH therapy on growth being observed in only those animals with more severe degrees of uremia. This growth-promoting action resulted from greater food efficiency and not from stimulated food intake. The hypercholesterolemia seen in NX rats, 81±2 mg/dl versus 55±3 mg/dl in SHAMAL (P0.0001), was not increased in the NX+GH group, 87±3 mg/dl. There was a positive and significant correlation between serum cholesterol and serum urea nitrogen values in NX and NX+GH animals. This study suggests that growth impairment of mild CRF is mainly due to malnutrition and is refractory to GH administration. GH therapy improves the growth rate of animals with advanced CRF without aggravating their lipid abnormalities. 相似文献
8.
正常与病态下嗓音的客观指标的评价 总被引:3,自引:0,他引:3
对158例正常人和136例各种喉疾病患者连续元音[i]发声时的平均气流率、声强、频率、频率微扰商和发声效率同步进行了测定.并对各测定指标间的相互关系进行了探讨.频率微扰商是表示连续元音发声时声带振动相邻周期间的微细变动量;发声效率反映平均气流率与声能的有效转换率.在低、中和高强度发声时.随发声强度的提高,平均气流率.频率和发声效率随之提高而频率微扰商则变小.中等声强发声时.平均气流率与声强,声强与频率均呈正相关;而平均气流率与发声效率.声强(男性)和频率(女性)与频率微扰商均呈负相关.多数喉疾病患者显示出较正常人高的平均气流率和频率微扰商,发声效率则降低.当声强和频率作为参考指标时,平均气流率,频率微扰商和发声效率可作为评价喉发声功能的客观、定量指标. 相似文献
9.
思想政治工作是我国高等教育的生命线,如何提高思想政治工作的质效是每一位教育工作者不能不关注的重大课题.实践证明,以"三个代表"为指引,以民主管理为重点,确立学生的中心地位,树精品战略,提高学生文化素养、科技创新等能力,能够很好地提高学生思想政治工作的质效,培养出适应时代需要的高级中医人才. 相似文献
10.
为深入贯彻落实"互联网+医疗健康"便民惠民活动,不断优化门诊服务流程,提高服务效率与质量,门诊管理者积极探索,创新服务模式,以微信公众号建设为突破口,主动宣传国家医改新政策,落实分级诊疗,提升服务水平。通过线上服务模式,加强与患者的沟通,提供贯穿诊前、诊中、诊后全流程的信息化便民服务,有效缓解了门诊"三长一短"的现象,实现了患者有序就医,患者满意度提高。尤其在疫情防控期间,对于减少人员聚集、保障就医安全等方面起到了积极的作用。 相似文献