CD4+CD25+调节T细胞与肿瘤免疫治疗策略

随着分子生物技术的不断发展,肿瘤的生物治疗在临床应用中的地位日渐突出,其中CD4+CD25+Foxp3+调节T细胞(CD4+CD25+Foxp3+regulatory T cell,Treg)在抑制肿瘤免疫方面起着重要作用,文章就其近年来在肿瘤免疫领域的研究进展作一综述.     

缺血性脑卒中患者阿司匹林抵抗现象及处理策略

阿司匹林作为缺血性脑血管病的一级和二级预防用药，广受关注。然而长期服用阿司匹林的患者仍会发生动脉血栓形成事件，因此本文就阿司匹林抵抗的概念、发生机制、检测方法、预防措施及其在缺血性脑血管病中的临床意义加以综述。     

音乐疗法在围手术期护理中的应用研究

目的：探讨音乐疗法在围手术期护理中的作用。方法：选择在我院实施局麻手术患者120例，随机分为观察组和对照组，两组均进行常规护理，观察组同时在术前、术中、术后收听自己喜欢的音乐。对两组焦虑水平、术中麻醉药用量和术后疼痛程度进行比较。结果：观察组术前SAS评分和焦虑发生率均明显低于对照组（P〈0．05），而术后两组无显著性差异（P〉0．05）；观察组术中咪唑安定使用量明显少于对照组（P〈0．05），利多卡因使用量也少于对照组，但无显著性差异（P〉0．05）；观察组术后疼痛分级明显低于对照组（P〈0．01）。结论：在同手术期护理中应用音乐疗法，可以减轻患者焦虑、减少麻醉药用量，缓解疼痛，促进康复。     

Dose reduction in CT examination of children by an attenuation-based on-line modulation of tube current (CARE Dose)

In a controlled patient study we investigated the potential of attenuation-based on-line modulation of the tube current to reduce milliampere values (mAs) in CT examinations of children without loss of image quality. mAs can be reduced for non-circular patient cross sections without an increase in noise if tube current is reduced at those angular positions where the patient diameter and, consequently, attenuation are small. We investigated a technical approach with an attenuation-based on-line control for the tube current realised as a work-in-progress implementation. The CT projection data are analysed in real time to determine optimal mAs values for each projection angle. We evaluated mAs reduction for 100 spiral CT examinations with attenuation-based on-line modulation of the tube current in a group of children. Two radiologists evaluated image quality by visual interpretation in consensus. We compared the mAs values read from the CT scanner with preset mAs of a standard protocol. Four different scan regions were examined in spiral technique (neck, thorax, abdomen, thorax and abdomen). We found the mAs product to be reduced typically by 10-60% depending on patient geometry and anatomical regions. The mean reduction was 22.3% (neck 20%, thorax 23%, abdomen 23%, thorax and abdomen 22%). In general, no deterioration of image quality was observed. There was no correlation between the age and the mean mAs reduction in the different anatomical regions. By classifying the children respectively to their weight, there is a positive trend between increasing weight and mAs reduction. We conclude that mAs in spiral CT examinations of children can be reduced substantially by attenuation-based on-line modulation of the tube current without deterioration of image quality. Attenuation-based on-line modulation of tube current is efficient and practical for reducing dose exposure to children.     

Noninvasive visualization of coronary arteries using contrast-enhanced multidetector CT: influence of heart rate on image quality and stenosis detection

OBJECTIVE: Although multidetector CT (MDCT) with retrospectively ECG-gated image reconstruction has been shown to permit noninvasive visualization of the coronary arteries, the 125-250 msec required for image acquisition frequently causes motion artifacts. We investigated the influence of a patient's heart rate on the presence of motion artifacts and on accuracy of stenosis detection on contrast-enhanced MDCT. MATERIALS AND METHODS: In 100 patients, MDCT was performed, and ECG-gated cross-sectional images were retrospectively reconstructed. From the 10 data sets obtained for each patient (reconstructed at 0-90% of the cardiac cycle in increments of 10%), we chose the best data set for every coronary artery. The images of the arteries were evaluated for occurrence of artifacts and the presence of high-grade stenosis (diameter reduction exceeding 70%) or occlusions. MDCT results were compared with coronary angiographic findings. RESULTS: Of the 400 coronary arteries, 115 (29%) could not be evaluated because of motion artifacts (n = 84) or other reasons (n = 31). Overall, 51 (49%) of 104 stenoses were revealed on MDCT. For detecting stenosis in those arteries that we could evaluate, MDCT had a sensitivity of 91% (51 of 56 stenoses detected) and a specificity of 89%. As the heart rate increased, the number of arteries that could be evaluated decreased, and overall sensitivity for stenosis detection decreased from 62% (heart rate < or = 70 beats per minute) to 33% (heart rate > 70 beats per minute). CONCLUSION: MDCT can reveal coronary stenoses, but the usefulness of MDCT as an aid in accurately evaluating stenoses decreases as a patient's heart rate increases.     

上颌窦提升在上颌后牙区萎缩牙槽嵴牙种植术中的应用

目的：探讨上颌窦提升术对上颌后牙区萎缩牙槽嵴患者种植义齿修复的临床应用价值。方法：56例患者植入196枚种植体，患者平均年龄60．6岁。将自体松质骨(Spongiosa)与Bio-OSS混合进行上颌窦提升术，根据情况一期或二期植入种植体。种植体植入后至少6个月，选用适当的上部修复体进行义齿修复。结果：上颌窦提升术后或／和种植体植入术后，创口愈合良好，未见种植体松动或脱落，供骨区和种植术区均未见并发症。术后12个月PTVs最小为-5，X线检查种植体周垂直骨吸收均不超过1mm。种植体全部稳定地行使功能。结论：应用上颌窦提升术对上颌后牙区萎缩牙槽嵴患者进行种植义齿修复有广阔的应用前景。     

CT: the unexpected evolution of an imaging modality

The evolution of CT can be characterized remarkably well by three phases of developments assigned to the 1970s, 1980s and 1990s. The first decade saw rapid innovations followed by a phase of consolidation and slow growth in the 1980s, and finally a third phase of very rapid development including spiral CT and multirow detectors in the 1990s. The evolution of technical developments during these first three decades is briefly reviewed. CT has reached a very high degree of maturity, mastering almost all clinical demands. The focus of this review is set on potential future developments and trends. Further doubling or multiplying of the numbers of slices acquired simultaneously cannot be expected to provide further essential innovations. New paradigms are required to advance the field. Future potential developments are outlined, including multisource, multidetector scanners for cardiac and dual-energy CT, new detector technologies, approaches to data handling and dose management.     

Multispectral analysis of magnetic resonance images

Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.