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排序方式: 共有453条查询结果,搜索用时 15 毫秒
61.
We report the first case of a child with mild dystrophinopathy associated with Klinefelter's syndrome (karyotype 47, XXY). This 3.5-year-old boy was affected by some symptoms suggestive of Becker's muscular dystrophy. Dystrophin immunostaining and immunoblotting procedures confirmed the diagnosis, but polymerase chain reaction-directed gene analysis failed to reveal any macrodeletion. Methylation-based assay did not show preferential X-inactivation. This confirmed the coexistence of the two active X-chromosomes (one of which was of paternal origin), thus accounting for the mild form of dystrophinopathy in this child affected by Klinefelter's syndrome. 相似文献
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Mark R. Hatswell W.Roy Jackson Francis P. Larkins Marc Marshall Douglas Rash Donald E. Rogers 《Fuel》1983,62(3):336-341
Some of the inherent cations of Victorian brown coals have been exchanged for iron by treatment with solutions of iron salts. Coals with various iron contents are obtained by variation of the pH of the solutions used. Hydrogenation of coals treated in this way at 395 °C, and an initial hydrogen pressure of 10 MPa, give product yields similar to those obtained using commercial cobalt molybdate on alumina catalysts, and greater than those obtained using red mud as a catalyst. The increase in yields compared with non-catalysed experiments results mainly from increased production of asphaltenes. The amount and composition of gas (80–90 wt% C02, resulting from decarboxylation) remains constant. Despite the similar conversions, the hydrogen consumption and tetralin/naphthalene ratios for iron-catalysed experiments are less than for cobalt—molybdate-catalysed experiments. 相似文献
67.
There are an increasing number of local area networks being developed and built for use in a wide range of environments. The underlying communication architecture in the majority of cases is either a broadcasting or ring system. This paper describes a gateway development system which is specifically designed to deal with the interconnection of broadcast and ring systems. The gateway makes use of recently developed microprocessor chips to handle the different requirements of the two networks being connected. In particular, the gateway will be used to link an Ethernet-like system and a Cambridge Ring. 相似文献
68.
Chalmers E Lou E Hill D Zhao VH Wong MS 《IEEE transactions on neural systems and rehabilitation engineering》2012,20(4):557-563
Bracing is a common nonsurgical treatment for scoliosis, but its effectiveness has been debated. Some clinical studies have shown efficacy of brace treatment is correlated to how the brace has been worn. The more often the patients wear their braces to the prescribed tightness as well as the prescribed length of wear each day, the better the treatment outcome. A system of four wireless pressure control devices was developed to understand brace wear-time and regulate a target pressure range at the brace-body interface. Each pressure control device could function independently and be embedded in the brace at key pressure areas. Such a system could improve the quality of brace wear-making the treatment more effective and refining our understanding of the three-pressure-point brace treatment concept during daily activities. This paper reports the system development and validation. The system was tested on four healthy subjects for 2 h without pressure regulation and 2 h with regulation. The results show that the pressure regulation doubled the time spent in a desired pressure range on average (from 31% to 62%). Brace-wear time was logged correctly. The system was also validated through a seven-day continuous test, and a fully charged battery could run for 30 days without requiring recharge. 相似文献
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Doug Bartow 《电子技术应用》2005,31(3):50-53
接要:介绍了典型的LCDTV为系统集成提供的模拟接口、数字接口,减少了内部连线,分析了“灵巧集成”的复杂度问题。采用在单芯片上集成多种接口和控制器功能的大规模集成电路可减少元器件的数量并且提高生产能力,但是有一定的风险。 相似文献
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Doug Stuetzle 《今日电子》2008,(7)
与传统超外差式接收器架构相比,直接转换接收器架构有许多优点.因为直接转换接收器不容易受镜频信号干扰,所以它降低了对RF前端带通滤波的要求.RF带通滤波器仅需要衰减较强的带外信号,以防止它们使前端过载.另外,直接转换接收器无须IF放大器和带通滤波器.RF输入信号直接转换成基带信号,在这种情况下,放大和滤波都容易了许多.这种接收器的总体复杂性降低了,器件数目也减少了. 相似文献