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81.
Aortopulmonary window (APW) is a rare congenital defect,found in 0.2% of patients with congenital heart disease,in which a communication exists between the ascending aorta and the pulmonary artery trunk with normal separation of the aortic and pulmonary valves. 相似文献
82.
Temporal tuning characteristics of the perceptual template and endogenous cuing of spatial attention
External noise presented in temporal contiguity with a target impairs perceptual performance, reflecting the temporal tuning of the perceptual template. Deriving the temporal characteristics of the perceptual template, however, requires an observer model that segregates the impact of non-linearities and intrinsic inefficiencies of the observer in order to account for the impact of external noise in various temporal configurations. In Experiment 1, we showed that the perceptual template model successfully accounts for temporal masking functions in foveal Gabor orientation identification masked by external noise with a wide range of temporal configurations, and estimates the temporal characteristics of the perceptual template. In Experiment 2, we extended the paradigm and the model to compare the temporal tuning characteristics of the perceptual template in central pre- and simultaneous cuing of endogenous spatial attention in a Gabor orientation identification task in visual periphery. We found that endogenous spatial attention excludes external noise by both sharpening the temporal window of the perceptual template and (mostly) reducing the impact of external noise uniformly across the entire temporal window. 相似文献
83.
Reproductive behaviour in modern western society has changed dramatically in the last two decades. Parenthood is now well
planned. If planned pregnancies do not occur as expected, early infertility care is often demanded with the risk of over-treatment.
Live birth rates in untreated subfertile couples reach nearly 55% in 36 months. During this period, self-monitoring with natural
family planning (NFP) methods may be all that is necessary, especially in couples with unexplained infertility.
Received: 30 August 2001 / Accepted: 19 December 2001
Correspondence to C. Gnoth 相似文献
84.
Blood donors must respond to standard control questions and comply to certain demands before donating blood, to exclude possible recent contamination. This study investigates whether donors had adequate knowledge about 'the immunological window period', and whether the standard questionnaire in use was understandable and clear. It was found that nearly 40% of the donors had inadequate knowledge about 'the immunological window period' and that 10-40% of the donors would respond in various ways to different interpretations of the formulations of the questionnaire, indicating that the questionnaire was ambiguous. It was concluded that these factors could increase the risk of donating on wrong conditions. Demands and control questions posed to donors must be void of ambiguous formulations and take proper account of actual human sexual behaviours and life styles. Finally, it is suggested that blood banks must offer practical solutions (such as a 'fake donation') for temporarily rejected donors in order to respect their private integrity. 相似文献
85.
Sequential non-invasive mechanical ventilation following short-term invasive m echanical ventilation in COPD induced hypercapnic respiratory failure 总被引:11,自引:1,他引:10
InChina ,80 % - 90 %ofpatientswithchronicobstructivepulmonarydisease (COPD )exacerbatedbecauseofbronchial pulmonaryinfection Someofthoseexperiencingsevererespiratoryfailureoftenrequiremechanicalventilation(MV) ,whichcanhelptocontrolpulmonaryinfectionandtakether… 相似文献
86.
Chronic experiments on guinea pigs were used to study the characteristics of cochlear nerve action potentials and the derived
potential in conditions of forward masking. The auditory nerve action potential was recorded from the round window of the
cochlea. The derived potential was obtained by subtracting the action potential recorded with masking from the response obtained
in silence. These studies showed that the derived potential showed higher sensitivity to masking than the traditional measure
of masking, i.e., the decrement in the amplitude of the auditory nerve action potential. The derived potential reflects not
only changes in the action potential during masking, but also changes in its shape. Differences between the derived potential
and the action potential decrement provide evidence that the amplitude and time changes in the derived potential provide more
complete information on the nature of activity in the auditory fibers.
Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 85, No. 6, pp. 751–766, June, 1999. 相似文献
87.
目的观察和比较鼓膜穿刺、鼓膜置管和圆窗置管微泵灌注地塞米松3种方法治疗难治性突发性感音神经性聋的疗效。方法55例常规方法治疗无效的突聋患者作为研究对象,其中圆窗置管微泵灌注用药治疗21例(置管组),每次2.5mg/0.5ml,维持1小时,每天两次,连续给药7天,总剂量35mg;鼓膜穿刺注药23例(穿刺组),首次剂量为2.5mg,此后,每2天重复注药1次(每次2.5mg),共4次,总剂量10mg;鼓膜切开置管滴药11例(滴药组),首次剂量为0.5%地塞米松0.5ml,经通气管滴入鼓室,每天重复滴药2次(每次2.5mg),共7天,总剂量32.5mg。同期常规方法治疗无效的32例突聋患者,且拒绝鼓室用药者随访作为对照(对照组),比较各组听力恢复及并发症情况。4组治疗前听力无显著差异(P>0.05)。结果治疗完成后1月纯音测听检查:置管组、穿刺组和滴药组平均PTA分别提高9dB、8.6dB和1.7dB,前2组明显高于对照组1.4dB(P<0.05),置管组8例(38.1%)听力改善约15~56dB,无效13例;穿刺组8例(34.8%)听力改善约16~54dB,无效15例;滴药组1例(9.1%)听力改善约26dB,无效10例;对照组3例(9.4%)听力改善约15~36dB,无效29例。结论鼓室灌注地塞米松治疗难治性突聋方法安全有效,为用常规方法治疗无效的突聋患者,提供了再次治疗的机会。 相似文献
88.
Teo EL Goldberg CS Strouse PJ Vermilion RP Bove EL 《Echocardiography (Mount Kisco, N.Y.)》1999,16(2):147-150
We present the pediatric case of a patient who had aortopulmonary window with interrupted aortic arch, intact ventricular septum, and pulmonary artery sling that was imaged with echocardiography and magnetic resonance imaging. This case is unique because this combination of findings has not been previously reported. The diagnosis was made without the need for angiography, and the findings were confirmed at surgery. This case shows that complex congenital heart defects can be accurately imaged by noninvasive methods. 相似文献
89.
Round window membrane rupture and acquired sensorineural hearing loss in children The aetiology of acquired sensorineural hearing loss includes many conditions. The disparity between the number of children affected by the conditions which are supposed to cause hearing loss and the number of children who are actually deaf, has never been satisfactorily explained. Clinical features observed in children with surgically proven round window membrane rupture have been noted in all conventional aetiological groups. These features include otitis media, doubt about the hearing status in early life, disturbance of balance and other occasional neurological phenomena. Wide variation in the appearance of round window niche has been observed in children with secretory otitis and similar appearances have been observed in children with proven round window membrane rupture. The appearances may represent a reaction to perilymph. Round window membrane rupture is probably common and may prove to be a unifying factor for many cases of acquired sensorineural hearing loss. Occasional neurological phenomena may be related to it. 相似文献
90.