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81.
The liver is the commonest site of metastatic disease for patients with colorectal cancer, with at least 25% developing colorectal liver metastases (CRLM) during the course of their illness. The management of CRLM has evolved into a complex field requiring input from experienced members of a multi-disciplinary team involving radiology (cross sectional, nuclear medicine and interventional), Oncology, Liver surgery, Colorectal surgery, and Histopathology. Patient management is based on assessment of sophisticated clinical, radiological and biomarker information. Despite incomplete evidence in this very heterogeneous patient group, maximising resection of CRLM using all available techniques remains a key objective and provides the best chance of long-term survival and cure. To this end, liver resection is maximised by the use of downsizing chemotherapy, optimisation of liver remnant by portal vein embolization, associating liver partition and portal vein ligation for staged hepatectomy, and combining resection with ablation, in the context of improvements in the functional assessment of the future remnant liver. Liver resection may safely be carried out laparoscopically or open, and synchronously with, or before, colorectal surgery in selected patients. For unresectable patients, treatment options including systemic chemotherapy, targeted biological agents, intra-arterial infusion or bead delivered chemotherapy, tumour ablation, stereotactic radiotherapy, and selective internal radiotherapy contribute to improve survival and may convert initially unresectable patients to operability. Currently evolving areas include biomarker characterisation of tumours, the development of novel systemic agents targeting specific oncogenic pathways, and the potential re-emergence of radical surgical options such as liver transplantation.  相似文献   
82.
重组人BAFF112-285的制备及活性分析   总被引:1,自引:3,他引:1  
目的 制备具有功能活性的重组人TNF家族的B细胞激活因子(B cell activating factor belonging to the TNF family,BAFF)胞外区112—285氨基酸残基段(rhBAFF112—285),为BAFF的深人研究奠定基础。方法 提取人HL-60细胞总RNA,经RT—PCR扩增编码人BAFF胞外区112—285氨基酸残基(BAFF112—285)的cDNA,行序列测定后,构建于原核表达载体pQE—80L并转化大肠杆菌DH5α,经IPTG诱导表达rhBAFF112—285,Ni^2 —NTA层析纯化,进而经^3H—TdR掺人实验检测其免疫学活性。结果 RT—PC双扩增得到了525bp的DNA片段,序列分析与GenBank中报道的编码人BAFF112—285的cDNA序列一致,该胞外区片段在大肠杆菌中获得了高效表达,表达水平达细菌总蛋白的45.7%,经纯化后纯度可达98.4%,活性检测证实其能明显刺激外周血淋巴细胞活化。结论 利用大肠杆菌可高效表达rhBAFF112—285,所获纯化产物具有生物学活性,所获结果为进一步研究创造了条件。  相似文献   
83.
多层螺旋CT评价先天性单冠状动脉畸形   总被引:1,自引:0,他引:1  
目的 探讨16层螺旋CT(MSCT)冠状动脉造影诊断先天性单冠状动脉畸形的价值。资料与方法 回顾性分析4例先天性单冠状动脉患者的MSCT和常规X线冠状动脉造影(CCA)资料。对比两者在显示和诊断此病中的差异。仿真内镜技术用于评价异位开口及其与邻近正常冠状动脉开口的关系,多平面重建、曲面多平面重建、最大密度投影、容积成像等重建方法则用于评价变异冠状动脉的行径及其与邻近大血管的关系。结果 4例患者变异的冠状动脉全部为MSCT造影所显示并明确诊断。MSCT显示3例患者的左主干起源于右冠状动脉的近段,其中1例在CCA中左主干仅近段局部显影,未能明确诊断,另2例左冠状动脉虽显影,但较淡。1例右冠状动脉起源于左主干的末端,CCA则误为起源于回旋支。MSCT显示2例异常开口冠状动脉的近段狭窄,3支异常冠状动脉穿过主动脉根部和肺动脉或右室流出道的间隙,1支绕主动脉根部后方走行,而CCA均不能明确诊断。结论 MSCT显示先天性单冠状动脉明显优于CCA,凡疑及冠状动脉变异的患者,可首选非创伤性的MSCT冠状动脉造影检查。  相似文献   
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85.
In a randomised, double-blind study, the effects of intramuscular injection of botulinum toxin type A (BtA) into the upper limb were compared with those of normal saline solution in 14 patients with cerebral palsy; their mean age was 9 years. Range of movement and function were assessed before injection and at 2 and 12 weeks after injection. BtA injection significantly increased maximum active elbow and thumb extension and significantly reduced tone at wrist and elbow. The hand grasp-and-release score improved, representing a modest functional change, but fine motor function, assessed by the ability to pick up coins, did not improve and in some cases deteriorated temporarily. The most notable subjective change was the cosmetic benefit of reduced involuntary elbow flexion. The tone-reducing effect of BtA was clinically detectable in comparison with the placebo and patients and parents perceived the change as beneficial. The median of changes in the treatment group was small but the range Was large, suggesting that BtA can be useful in selected patients.  相似文献   
86.
研究酸蚀对光敏玻璃离子的微渗漏影响。方法:采用侵害性窝沟封闭技术处理36颗人离休磨牙,并随机分成3组,每组12颗,第Ⅰ组为对照组,用37%磷酸酸蚀后,用低粘稠度复合树脂Liquicoat封闭窝沟裂隙。第Ⅱ组处理同第Ⅰ组,用低粘稠度光敏玻璃离子PrimaFlow封闭窝沟裂隙。第Ⅲ组与第Ⅱ组不同之处,对牙釉质不进行酸蚀。每组半数牙齿进行热循环处理(5~55℃,2500周)。所有标本用0.5%亚甲基蓝着色,在立体显微镜下观察微渗漏等级。结果:微渗漏第Ⅰ组与第Ⅱ组相似(P>0.05)。第Ⅰ、Ⅱ组较第Ⅲ组小(P<0.001)。复合树脂经热循环处理后微渗漏有增加(P<0.01),而光敏玻璃离子粘固粉经热循环处理后微渗漏没有增加(P>0.05)。结论:光敏玻璃离子结合酸蚀技术能减少微渗漏。  相似文献   
87.
Lo  SC; Huang  HK 《Radiology》1986,161(2):519-525
A comprehensive study was performed using the full-frame bit-allocation compression technique on 78 radiological images, including digitized radiographs, computed radiographs, and computed tomography images. Each radiograph was digitized to 2,048 X 2,048 X 10, 1,024 X 1,024 X 10, and 512 X 512 X 10 matrices, respectively, with a laser scanner. Five compression ratios were used to compress each image, and reconstructed images from each compressed data set were obtained. Altogether, the authors studied 842 images, including the original and compressed-reconstructed images and the images obtained from the difference between the original and the reconstructed images. The results indicate that acceptable compression ratios for 2,048, 1,024, and 512 matrices are 25:1, 20:1, and 10:1, respectively, based on a mean-square error of 0.02%.  相似文献   
88.
The molecular mechanisms of migraine pain have not yet been clarified. Monoamine and the peptide neurotransmitters involved in neurogenic inflammation do not cause significant head pain. Our previous studies of glyceryl trinitrate (GTN) and histamine-induced headaches have suggested that nitric oxide (NO) is the causative molecule in migraine pain. We furthermore suggest that substances capable of inducing experimental vascular headache do so via a common mediator which is NO. Finally, it is suggested that drugs exert their antimigraine activity by inhibiting NO or subsequent steps in the cascade of intracellular reactions triggered by NO. These novel observations change current views on vascular headache mechanisms and the importance of NO as an initiator of the migraine attacks dictates new approaches to the pharmacological treatment of migraine and other vascular headaches.  相似文献   
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