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1.
目的:确定宫内诊断为单纯先天性Ⅱ度房室传导阻滞但母体血清抗-SSA/R o-SSB/La抗体阴性的胎儿围生期结局。方法:单纯先天性Ⅱ度房室传导阻滞定义为宫内诊断为Ⅱ度房室传导阻滞但不伴有心脏结构异常、快速性心律失常、非诱发性房性早搏、Q T间期延长综合征。单纯先天性Ⅱ度房室传导阻滞的病例来源于本院已有病例及从M edline数据库以房室传导阻滞、心律失常、心动过缓以及先天性为关键词检索得到的病例。结果:本院收集到2例病例,从M edline数据库收集到5例病例。对此7例宫内诊断为单纯先天性Ⅱ度房室传导阻滞但母体血清抗-SSA/Ro-SSB… 相似文献
2.
Since 1990, prostate cancer (PCa) has been the most common non-skin cancer in American men, even snrpassing lung cancer. Because the mean age of the American population continues to increase while mortality from other causes continues to decrease, the incidence and mortality of PCa are likely to slay relative high level because the incidence of PCa rises significantly in men over 50-55 years old. 相似文献
3.
近年来在肿瘤化疗方面取得了一定疗效,相应地提高了肿瘤5年存活率。化疗的主要作用是抑制去氧核糖核酸(DNA)合成,无选择地对癌细胞、正常细胞起杀伤破坏作用,故在化疗期正常骨髓细胞往往受到损害,常引起血液及实质脏器毒性,重者导致死亡。本文重点综述抗癌药物的副作用及其处理。 相似文献
4.
5.
世界肾脏替代的新进展上海第一人民医院谢桐中国透析移植研究会(CDTA)成立以来。加强了肾脏替代这一重要学科的国际学术交流,同时,在内外科医师的密切结合下,通过每年的学术活动,使我国救治终末期肾病患者透析和移植的数量和质量在勇猛前进。终末期肾病的发病率... 相似文献
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7.
Radiologic and pathologic mani;estations of 30
peripheral pulmonary masses around l.5-3 cm in dia-
meter were compared to the pathologic basis of va-
cuole sign and small node sign on tomogram. Stati
stics of 100 conventional X-ray tomograms of peri-
pheral pulmonary masses about l-3 cm in diameter
suggested that the vacuole sign and small node sign,
more common in early peripheral lung cancer than
in tuberculoma, are valuable for differentiating early
peripheral lung cancer from tuberculoma. 相似文献
8.
WIF1, a component of the Wnt pathway, is down-regulated in prostate, breast, lung, and bladder cancer 总被引:19,自引:0,他引:19
9.
This study examined the acquisition and transfer of a fine motor skill, namely the rotary pursuit, in 99 patients with Alzheimer's disease (AD) and 100 normal controls (NCs). To identify optimal learning strategies, the authors had participants practice the rotary pursuit under constant, blocked, random, or no training conditions. Transfer was assessed using speeds that were different from those practiced during acquisition. AD patients and NCs receiving constant practice outperformed their peers in the blocked and random conditions during acquisition. Whereas all 3 types of practice facilitated transfer in the NCs, AD patients only benefited from constant practice. The inability of the AD patients to benefit from variable practice suggests that these individuals may have difficulty accessing and/or forming motor schemas. 相似文献
10.
In computed tomography (CT), the beam hardening effect has been known to be one of the major sources of deterministic error that leads to inaccuracy and artifact in the reconstructed images. Because of the polychromatic nature of the x-ray source used in CT and the energy-dependent attenuation of most materials, Beer's law no longer holds. As a result, errors are present in the acquired line integrals or measurements of the attenuation coefficients of the scanned object. In the past, many studies have been conducted to combat image artifacts induced by beam hardening. In this paper, we present an iterative beam hardening correction approach for cone beam CT. An algorithm that utilizes a tilted parallel beam geometry is developed and subsequently employed to estimate the projection error and obtain an error estimation image, which is then subtracted from the initial reconstruction. A theoretical analysis is performed to investigate the accuracy of our methods. Phantom and animal experiments are conducted to demonstrate the effectiveness of our approach. 相似文献