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1.
Various forms of signal processing are used in modern ASP hearing aids. The present study investigated the relationship between sentence recognition ability and two types of signal processing used in commercially available hearing aids. Results indicated a significant improvement in sentence recognition ability employing an instrument with adaptive compression (variable release time) versus an instrument with an adaptive high-pass filter with short attack and release times. Data were obtained for a single-talker competing message at several message-to-competition ratios. The adaptive compression system may prove to be beneficial to hearing-impaired listeners in certain background noise environments.  相似文献   
2.
发挥远程教育优势推进医学继续教育发展   总被引:9,自引:0,他引:9  
《教育部关于加强高校网络教育学院管理提高教学质量的若干意见》中强调指出:高校网络教育学院要以在职人员的继续教育为主,要充分发挥网络教育的优势,为在职人员更新知识、增强技能、不断学习、不断提高提供良好的服务。然而,要使医学院校在开展继续教育中发挥更大的作用,推进医学继续教育的发展,远程教育不仅是解决这一问题的有效途径,而且将成为开展医学继续教育的强大动力。  相似文献   
3.
We present a case of Bernard Soulier syndrome in a 9-year-old boy caused by a novel genetic mutation. This child was shown to be homozygous for a single nucleotide deletion (c.1077delG) in the GP1BA gene not previously reported. Clinically, the boy has become refractory to platelet transfusions with both allo-antibodies and iso-antibodies and a massive transfusion requirement for ongoing haemorrhage. We describe the critical role that the blood product transfusion continues to play in the management of Bernard Soulier syndrome and discuss therapeutic options in these patients.  相似文献   
4.
Cancer is one of the leading causes of death in human, and among various cancers, gastrointestinal cancers occupy more than 55%. Gastric cancer is the first leading cause of cancer-related mortality in the world and the number of pancreas and colon cancers are increasing remarkably during last two decades which will continue to increase in the future. Even though the clinical importance of gastrointestinal cancers is very high and endless efforts has been made to develop novel diagnostic and therapeutic methods to improve the patient's quality of life and survival, the realistic advance in the actual survival benefit of the cancer patients are still strongly required. Nanotechnology has the power to radically change the way of cancer diagnosis and treatment. Currently, there is a lot of researches on novel nanodevices capable of detecting cancer at its earliest stage, pinpointing its location within the body, and delivering anticancer drugs specifically to the malignant cells. Nanoscale devices can readily interact with biomolecules both on the cell surface and within the cell. In addition, nanoscale devices are already proven that they can deliver therapeutic agents to target cells even within specific organelles. Major areas in which nanomedicine is being developed in cancer include early detection and proteomics, imaging diagnostics and multifunctional therapeutics. Because nanotechnology would provide a technical power and tool that enable new diagnostics, therapeutics, and preventives to keep pace with today's explosion in knowledge in the future, it would be very useful to know the perspectives in the direction of nanotechnology as a major clinician responsible for the patients with gastrointestinal malignancies.  相似文献   
5.
HQJ-500多功能净水装置装舰试用评价   总被引:1,自引:1,他引:0  
目的:改善舰船官兵的饮用水水质,提高舰员的生活质量。方法:将研制的HQJ-500多功能净水装置装舰试用,征求试用意见并进行水质分析。结果:经实船试用证实,该多功能净水器能经受住各种海况下颠簸,摇晃的考验。运行正常。处理后的水质有明显改善。结论:该装置净化,消毒效果肯定,适合舰船使用,可推广应用。  相似文献   
6.
E M Spencer  C C Liu  E C Si  G A Howard 《BONE》1991,12(1):21-26
The in vivo action of insulin-like growth factor-I on bone metabolism has been studied using a new model. Insulin-like growth factor-I (IGF-I) was continuously infused into the arterial supply of the right hindlimb of ambulatory rats for up to 14 days and the effects on cortical and trabecular bone formation and the number of osteoclasts were determined by histomorphometric techniques. The contralateral limb acted as an internal control. IGF-I infusion significantly increased cortical bone formation (p less than 0.01). Trabecular bone was increased 22% (p = 0.07), but the infusion was only for seven days. These effects of IGF-I were age dependent, being absent in young, rapidly growing animals, but present at least until one year of age. IGF-I appears to be a purely anabolic hormone for bone formation, since it significantly stimulates osteoblasts and decreases the number of osteoclasts. Thus, although IGF-I mediates the growth-promoting effect of growth hormone, it does not mediate growth hormone's action on bone resorption.  相似文献   
7.
Using abdominal ultrasonographic data and laboratory tests, radiologists often find differential diagnoses of hepatic masses difficult. A computerized second opinion would be especially helpful for clinicians in diagnosing liver cancer because of the difficulty of such diagnoses. A back-propagation neural network was designed to diagnose five classifications of hepatic masses: hepatoma, metastic carcinoma, abscess, cavernous hemangioma, and cirrhosis. The network input consisted of 35 numbers per patient case that represented ultrasonographic data and laboratory tests. The network architecture had 35 elements in the input layer, two hidden layers of 35 elements each, and 5 elements in the output layer. After being trained to a learning tolerance of 1%, the network classified hepatic masses correctly in 48 of 64 cases. An accuracy of 75% is higher than the 50% scored by the average radiology resident in training but lower than the 90% scored by the typical board-certified radiologist. When sufficiently sophisticated, a neural network may significantly improve the analysis of hepatic-mass radiographs.  相似文献   
8.
深圳市龙岗区坪地外来工亚健康状态的研究   总被引:5,自引:0,他引:5  
目的 :探讨深圳市龙岗区坪地外来工亚健康状况及其影响因素 ,为预防亚健康提供科学依据。方法 :采用统一表格对 12 68深圳市龙岗区坪地外来工进行调查。结果 :外来工的平均年龄为 ( 2 4.96± 6.10 )a ,其亚健康状态总体发生率为 65 .3 0 %,男性亚健康状态发生率为 63 .2 1%,女性为 67.91%,男性和女性之间差异无统计学意义。亚健康状态主要影响因素为 :结婚与否、睡眠时间、工作时间、加班时间以及工作是否有压力和居住环境差等因素 ,而与吸烟、饮酒、文化程度等因素无相关。结论 :深圳龙岗区坪地外来工中普遍存在亚健康状态 ,其发生较高且与工作环境、工作时间、加班时间有密切关系 ,故应引起政府部门及社会各界高度重视 ,加强对外来工的健康保护  相似文献   
9.
10.
We developed a technique of translocation of the pulmonary artery anterior to the ascending aorta without transection of the aorta in the repair of tetralogy of Fallot with absent pulmonary valve. Our technique includes detachment of the main pulmonary artery (MPA) from the pulmonary annulus, vertical division of the MPA, anterior translocation of the pulmonary artery with patch augmentation between the vertically divided MPA.  相似文献   
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