GE宝石能谱CT故障分析

简要介绍了GE宝石能谱CT(Discovery CT750 HD)的技术特点,详细阐述了日常使用中出现的间歇性停机、无法进行Fastcal(快速空气校正)以及扫描中断和gantry(扫描架)自动复位3例故障的维修过程,为医院维修人员维修类似故障提供了参考。最后总结了医疗设备常见故障及主要故障原因,提出了快速排查CT故障的方法,并建议在日常使用中及时保养维护以降低设备故障率。     

Practical uses of contrast‐enhanced spectral mammography in daily work: A pictorial review

Contrast‐enhanced spectral mammography (CESM) has a number of uses including the work‐up of inconclusive findings on mammography, assessment of breast symptoms, cancer staging, evaluation of response to neoadjuvant chemotherapy and recently as an alternative to magnetic resonance imaging (MRI) in high‐risk screening. CESM can be swiftly incorporated into the workflow of busy breast clinics. We share our experiences with CESM at a large breast assessment centre in Western Australia.     

Cerebral autoregulation is preserved in multiple system atrophy: A transcranial Doppler study.

Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA.     

Alternating repetition time balanced steady state free precession.

A novel balanced SSFP technique for the separation or suppression of different resonance frequencies (e.g., fat suppression) is presented. The method is based on applying two alternating and different repetition times, TR(1) and TR(2). This RF scheme manipulates the sensitivity of balanced SSFP to off-resonance effects by a modification of the frequency response profile. Starting from a general approach, an optimally broadened stopband within the frequency response function is designed. This is achieved with a TR(2) being one third of TR(1) and an RF-pulse phase increment of 90 degrees . With this approach TR(2) is too short ( approximately 1 ms) to switch imaging gradients and is only used to change the frequency sensitivity. Without a significant change of the spectral position of the stopband, TR(1) can be varied over a range of values ( approximately 2.5-4.5 ms) while TR(2) and phase cycling is kept constant. On-resonance spins show a magnetization behavior similar to balanced SSFP, but with maximal magnetization at flip angles about 10 degrees lower than in balanced SSFP. The total scan time is increased by about 30% compared to conventional balanced SSFP. The new technique was applied on phantoms and volunteers to produce rapid, fat suppressed images.     

睾丸旁促结缔组织增生性小圆细胞肿瘤1例报告及文献复习

目的:探讨睾丸旁促结缔组织增生性小圆细胞肿瘤的临床、病理特征、诊断及治疗。方法:回顾分析1例睾丸旁促结缔组织增生性小圆细胞肿瘤的诊治及随访资料,并复习相关文献。患者,男,27岁,因阴囊内无痛性肿块4个月就诊。体检于左侧阴囊内可扪及囊性肿块,同侧睾丸不能扪及。行左侧睾丸根治性切除术,术后辅以化疗。结果:术中见左侧睾丸旁多发结节状隆起肿块,质偏硬;术后病理检查肿瘤细胞呈巢状或梁索状结构并埋没在增生的纤维结缔组织中;免疫组化显示瘤细胞具有上皮源性、间质性和神经源性等多向分化的特点。术后已随访3年无瘤生存,预后良好。结论:促结缔组织增生性小圆细胞肿瘤有特异的临床病理特征,好发于年轻男性,手术切除肿瘤联合化疗是治疗的主要方法,睾丸旁促结缔组织增生性小圆细胞肿瘤比腹腔型预后相对好。     

基于广义逆的无谱逆反卷积算法

在时域循环卷积运算实现反卷积方法的基础上，基于广义逆的概念提出了一种改进算法，该算法不仅可以有效地避开无谱逆问题，而且运算量增加较少，易于编程实现。     

金地鼠颊囊癌前病变的细胞增殖动力学研究

目的研究口腔上皮组织癌和癌前病变的细胞动力学变化特征。方法采用Ｓａｌｅｙ的ＤＭＢＡ涂布诱导法，建立金地鼠颊囊癌前病变模型，并用溴脱氧尿苷流式细胞动力学检测方法，对３０只叙利亚种金地鼠进行分组对照研究。结果涂药组光镜下的细胞病变程度随涂药时间延长而逐渐加重，而空白对照组无变化；ＦＣＭ检测显示涂药组与对照组在Ｓ期阳性细胞检出率存在显著差异。即使在光镜下表现为轻度不典型增生时，ＦＣＭ检测结果也有显著差别。结论金地鼠颊囊癌前病变具有细胞异常增殖的细胞动力学特征     

Correlations between the pharmacokinetics and dynamics of pharmacological effects of bromantane

It is shown that there is a mathematical correlation between an integral characteristic of activity of the organism (the capacity for work), electrophysiological indexes of functioning of the brain structures, and the concentration of a novel derivative of 2-aminoadamantane, bromantane, in the brain. The nature of the correlation between integral characteristics of the organism studied on different levels is found to change depending on the time elapsed from the administration of the preparation and on its concentration in the blood or target tissue. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3 pp. 305–308, March, 1995 Presented by M. D. Mashkovskii, Member of the Russian Academy of Medical Sciences     

聋幼儿情绪状态对认知发展的影响

为促进聋幼儿各方面的正常发展，使其早日回归主流社会，我们对聋幼儿进行了认知和情绪表现的研究。通过问卷调查、观察和实验研究得知，聋幼儿的认知发展和良好情绪的培养是分不开的，认知内容适中有利于聋幼儿良好情绪的培养，而良好积极的情绪又可促进聋幼儿认知的发展。对此，我们实验并总结了培养聋幼儿积极情绪和促进认知发展的方法。