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31.
目的:研究肝郁痰凝型乳腺癌的钼靶X线影像特点,探讨其病理基础。方法:观察41例中医证型为肝郁痰凝型、术后病理检查结果为乳腺癌患者的钼靶X线影像表现,对其病理学基础进行分析。结果:41例肝郁痰凝型乳腺癌中,乳腺类型以致密型及混合型居多(占78%)。异常血管征及透环征出现频率较高(占80%以上)。腋淋巴结转移出现频率偏低(占12%)。结论:(1)肝郁痰凝型乳腺癌患者,乳腺密度多偏高,可能与较多发生在绝经期前有关。(2)肿瘤周围透亮环征象及异常血管征象出现频率较高,表明此型患者肿块周围脂肪代谢异常较为普遍及血管生长刺激因子分泌较多。(3)腋窝淋巴结转移者所占比例较小,可能是由于此类患者多属于癌变早、中期,相对气血不足或脾肾虚弱等正虚表现不明显。 相似文献
32.
目的评价中心静脉导管留置治疗胸腔积液的疗效。方法257例胸腔积液患者分为两组,治疗组207例,应用胸腔留置中心静脉导管治疗;对照组50例,常规胸穿抽液治疗,观察并比较不同治疗方法的疗效、并发症等指标。结果两组对比多项指标差异有显著性(P〈0.05)。结论采用中心静脉导管治疗胸腔积液可减少胸穿次数、降低反应,提高治愈率。 相似文献
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35.
Goetz P Blamire A Rajagopalan B Cadoux-Hudson T Young D Styles P 《Journal of neurotrauma》2004,21(6):645-654
Following diffuse traumatic brain injury, there may be persistent functional or psychological deficits despite the presence of normal conventional MR images. Previous experimental animal and human studies have shown diffusion abnormalities following focal brain injury. Our aim was to quantify changes in apparent diffusion coefficient (ADC) and absolute relaxation times of normal appearing white matter (NAWM) in humans following traumatic brain injury. Twenty-three patients admitted with a diagnosis of head injury (nine mild, eight moderate, and six severe) were scanned an average of 7.6 days after injury using a quantitative echo planar imaging acquisition to obtain co-registered T1, T2, and ADC parametric maps. Mean NAWM values were compared with a control group (n = 13). The patient group showed a small but significant increase in ADC in NAWM, with no significant change in T1 or T2 relaxation times. There was a correlation between injury severity and increasing ADC (p = 0.03) but no correlation with either T1 or T2, suggesting that ADC is a sensitive and independent marker of diffuse white matter tissue damage following traumatic insult. None of the patients had a reduced ADC, making ischaemia unlikely in this cohort. Pathophysiological mechanisms that may explain diffusely raised ADC include vasogenic edema, chronic ischemic phenomena, or changes in tissue cytoarchitecture or neurofilament alignment. 相似文献
36.
M?ChakravarthyEmail author V?Jawali M?Manohar TA?Patil K?Jayaprakash NV?Shivananda 《Indian Journal of Thoracic and Cardiovascular Surgery》2003,19(3):151-154
Conclusion Our case report highlights the possibility of tackling mediastinal, pericardial and pleural problems with regional anesthesia
alone even if the surgery requires opening of the pleura. 相似文献
37.
Corkill RG Garnett MR Blamire AM Rajagopalan B Cadoux-Hudson TA Styles P 《Clinical neurology and neurosurgery》2003,105(3):193-202
Magnetic resonance techniques were used to investigate haemodynamic abnormalities and their consequences in normal pressure hydrocephalus (NPH) and to assess changes in these parameters following surgery. Eleven patients with NPH were studied pre- and post-operatively using perfusion and diffusion weighted imaging and compared with ten age-matched controls. Pre-operative periventricular relative cerebral blood volume (rCBV) was reduced in patients (0.76+/-0.11) compared with control (1.16+/-0.16, P<0.01). There was no difference between outcome groups and no change in haemodynamic parameters following surgery. The periventricular apparent diffusion coefficient (ADC) was elevated in the poor outcome group (1.67+/-0.3 x 10(-3) mm(2) s(-1)) compared with both controls (1.04+/-0.4 x 10(-3) mm(2) s(-1), P<0.05) and the good outcome group (0.99+/-0.3 x 10(-3) mm(2) s(-1), P<0.05) despite appearing normal on conventional imaging. In white matter hyperintensities (WMH), rCBV was reduced (0.70+/-0.12 vs. 1.00+/-0.10, P<0.01), and the ADC was increased (1.98+/-0.6 vs. 1.04+/-0.4 x 10(-3) mm(2) s(-1), P<0.05) compared with the same anatomical location in controls. As low rCBV and high ADC is characteristic of chronic infarction, the findings in WMH regions suggest they are irreversibly damaged. Normal appearing periventricular tissue rCBV was reduced, implying that significant haemodynamic consequences contribute to symptoms in NPH. The elevated pre-operative ADC of the same region, was correlated with poor outcome, and may, therefore, be useful in selecting patients for surgery. 相似文献
38.
陶瑞卿 《四川生殖卫生学院学报》2007,(6):32-35,55
公共产品涉及千家万户的切身利益,近10多年来,部分公共产品价格变化又多以超过国民经济发展速度提高,怎样正确认识和判断其价格的合理性,具有十分重要的现实意义。本文分析了我国公共产品的价格类型,定价机制,阐明了我国公共产品的价格约束制度构建的主要内容,希望为政府及相关部门工作提供有益的帮助。 相似文献
39.
美国食品和药物管理局(Food and Drug Administration,FDA)经过多年发展和改革,已形成了成熟的上市前监管体系。本文通过对FDA上市批准路径(上市前批准、上市前通告、人道主义用器械豁免)和申报流程进行系统介绍,总结了加强事前沟通、降低产品风险等级和设立实质审查程序三个方面的启示,希望我国监管机构能充分吸收美国FDA对于医疗器械监管的经验和教训,建立适合中国国情的医疗器械监管体系,确保公众用器械安全。 相似文献
40.
WANG Qing-sheng TA Na RAO Zhu-shi 《中国生物医学工程学报(英文版)》2007,16(4):148-154
It is reported that some types of insects have a remarkable ability to detect the direction of an incident sound even though its acoustic sensory organs are in very close proximity each other. Maybe the ears are jointed by a cuticular structure with which the separated motions can be coupled mechanically and thus be magnified. In this paper, a detailed model is setup to describe the principle of this type of localization using a mechanical coupled structure. The transfer functions and the responses of the model in terms of time and frequency are analyzed to describe the mechanism of its ability of directional hearing. This analytical model provides a method to design the experimental model for the predetermined incident sound pressure, and the analysis of this model shows that this structure have the ability to determine the direction of the incident stimulus. 相似文献