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1.
Paradoxical embolism, describing the passage of venous or right-sided cardiac thrombus into the arterial or systemic circulation through patent foramen ovale, is an uncommon cause of acute arterial occlusion. Here, we report acute Leriche syndrome in a young woman attributable to paradoxical embolism. Ischaemia, patent foramen ovale, and venous thrombosis were the triad of evidence for paradoxical embolism.  相似文献   
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SUMMARY Four specialised air mattresses had interface pressure measured under six body sites prone to pressure sores in 10 subjects, supine and sitting. The mattresses were the Clinirest (SSI) and FirstStep (KCI) continuous airflow mattress overlays, and Airwave (Pegasus) and Nimbus (Huntleigh) alternating pressure air mattresses. On the mattress overlays, average supine interface pressures were 2.33 kPa (scapula), 4.15 kPa (elbow), 1.94 kPa (sacrum) and 2.79 kPa (buttock), although they were higher at the occiput (7.97 kPa) and heel (11.7 kPa). The alternating pressure air mattresses had an average minimum interface pressure close to zero for three sites, rising to 4.28 kPa under the heel. Average maximum interface pressures were 8.61 kPa (occiput), 5.21 kPa (scapula), 4.90 (elbow), 4.85 kPa (sacrum), 4.61 kPa (buttock) and 13.2 kPa (heel). No accepted scientific method exists for comparing the two types of mattress. Our data suggest a clinical benefit at the occiput and heel (supine) in using an alternating pressure air mattress and a benefit in using a continuous airflow mattress overlay at other sites.  相似文献   
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MacEwan  DW 《Radiology》1987,163(2):559-563
Eleven radiologists appointed by the major radiological societies participated for the past 5 years in the development of the Health Policy Agenda for the American People. The Agenda is an action plan to address a wide variety of serious problems in medicine. The first phase involved establishment of 159 principles, broad value statements that were the foundation of the project. Phase 2 involved the development of policy proposals on 38 urgent issues for action in medical science; education; health resources; delivery mechanisms; evaluation, assessment, and control; and payment for services. These proposals are summarized in this report. The activities and recommendations of representatives for the field of radiology are described. The Agenda has been released, and an implementation phase has begun. It will likely be of great importance to the practice of radiology over the next decade. Important issues can be addressed by acting with the coalitions that are being formed from among the more than 150 participating organizations.  相似文献   
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We investigated the effect of the lgG from patients with myasthenia gravis (MG) on the degradation of normal rat junctional acetylcholine receptor (AChR) labeled with 125l-α-bungarotoxin (BuTx) and calculated the degradation rate (DR). The DR for the lgG from these patients was significantly higher than that from healthy volunteers and patients with other autoimmune diseases. For MG, DR was significantly correlated with the severity of the disease but not with anti-AChR antibody titer. DR was accelerated by lgG from patients with generalized MG whose antibody titers were in the normal range and by lgG from patients with ocular MG. These results indicate that measurement of the DR of junctional AChR in normal rats is more closely correlated with the severity of the disease than is measurement of anti-AChR antibody and that the former is a sensitive and confirmatory method for evaluating MG. © 1993 John Wiley & Sons, Inc.  相似文献   
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Klinefelter综合征患者和双亲对诱变剂敏感性研究   总被引:1,自引:1,他引:1  
为了解诱变剂对Klinefelter综合征发生的影响,对Klinefelter综合征患者,患者双亲及对照进行丝裂霉素C,乙醛或乙醇诱导非二倍体,染色体结构畸变及微核观察,发现丝裂霉素C诱导的患者当色体结构畸变和微核均显著多于对照和双亲,乙醛和乙醇能诱导非二倍体和微核增加,但患者和双亲增加的程度极显著高于对照,提示Klinefelter综合征患者对于丝裂霉素C,乙醛和乙醇诱导染色体畸变更敏感。双亲对  相似文献   
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首次选用双相成核剂CaF2 和TiO2 为制备遮色瓷的成核剂 ,以SiO2 —Al2 O3 —K2 O—Na2 O系统为其基质成分 ,采用差热分析仪、扫描电镜和x衍射分析仪等实验手段来探讨本体系遮色瓷制备的热处理制度。结果表明阶梯制度的热处理方式适用于本体系的遮色瓷。瓷粉经过如下的热处理制度 :从室温以 8℃ /min的加热速度升温至 75 0℃保温 1h ,然后再以4℃ /min的升温速度升至 96 0℃ ,保温 2h后冷淬 ,其白榴石晶体的析晶行为良好 ,且晶体尺寸较小 (约 1μm左右 )。该热处理制度的确定为改善遮色瓷与金属的热匹配性和提高遮色瓷的理化性能提供了基础  相似文献   
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