In vivo 13C saturation transfer effect of the lactate dehydrogenase reaction.

Lactate dehydrogenase (LDH, EC 1.1.1.27) catalyzes an exchange reaction between pyruvate and lactate. It is demonstrated here that this reaction is sufficiently fast to cause a significant magnetization (saturation) transfer effect when the 13C resonance of pyruvate is saturated by a continuous-wave (CW) RF pulse. Infusion of [2-(13)C]glucose was used to allow labeling of pyruvate C2 at 207.9 ppm to determine the pseudo first-order rate constant of the unidirectional lactate-->pyruvate flux in vivo. During systemic administration of GABAA receptor antagonist bicuculline, this pseudo first-order rate constant was determined to be 0.08+/-0.01 s-1 (mean+/-SD, N=4) in halothane-anesthetized adult rat brains. In 9L and C6 rat glioma models, the 13C saturation transfer effect of the LDH reaction was also detected in vivo. Our results demonstrate that the 13C magnetization transfer effect of the LDH reaction may be useful as a novel marker for utilizing noninvasive in vivo MRS to study many physiological and pathological conditions, such as cancer.     

肱骨近端记忆接骨器的设计与临床应用

目的 探索肱骨头解剖颈至外科颈及肱骨近端干段骨折、骨不连的内固定新技术。方法 根据生物记忆材料镍钛合金性能与肱骨近端解剖生理特征，研制肱骨近端记忆接骨器（proximal humerus memory connector，PHMC），并临床治疗肱骨近端粉碎性骨折、畸形愈合、骨不连共22例。患者平均年龄41．7岁，平均随访18．5个月。结果 骨折骨性愈合时间平均3．6个月；骨不连骨性愈合时间平均4．5个月。骨愈合形式均呈骨板样骨替代，未见无序骨痂出现。PHMC术后弃用外固定，创伤反应期（7～12d）后，进行主动渐进性功能锻炼。肩关节功能按Michael Reese评分，平均88．5分。结论 PHMC能有效治疗肱骨解剖颈始至肱骨近端的各类型骨折与骨不连，亦为减少该部的假体关节置换探索出了新路。     

成人肾母细胞瘤的诊断与治疗(附9例报告及文献复习)

目的探讨成人肾母细胞瘤的诊断和治疗方法。方法回顾性分析9例成人肾母细胞瘤的临床表现、分期、治疗及预后。结果9例患者按照美国国家肾母细胞瘤研究组（National Wilms Tumor Study,NWTS）分期：Ⅰ期3例,Ⅱ期3例,Ⅲ期2例,Ⅳ期1例。9例均行肾切除术,其中术前分别辅以化疗1例、放疗1例、肾动脉介入栓塞化疗2例。9例术后辅以放疗和化疗。8例获得随访,随访1-6年,7例生存。结论成人肾母细胞瘤是一种比较少见的恶性肿瘤,早期诊断、手术治疗、辅以放疗和化疗等可明显提高治愈率并改善其预后。     

Performance measurement of the microPET focus 120 scanner.

The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals.     

重组人白介素-24蛋白对荷人A375细胞黑素瘤裸鼠的抑瘤作用

目的 研究原核表达及纯化、复性的重组人白介素24蛋白(recombined human interlukin 24,rhIL-24)对荷人A375细胞黑素瘤裸鼠的抑制肿瘤生长的作用.方法 将人A375黑素瘤细胞注射至裸鼠体内,待肿瘤生长到一定体积后,向裸鼠的肿瘤内注射rhIL-24,2周后切取肿瘤称重、量体积,进行病理检查及免疫组化检测.结果 经rhIL-24注射的肿瘤体积及重量与对照组相比明显减小、减轻;Bax基因表达上调、Bcl-2、CD34及VEGF基因表达下调,显示肿瘤细胞生长受到抑制,凋亡率增加.结论 rhIL-24对荷人A375细胞黑素瘤裸鼠的肿瘤有显著抑制生长的功能,可促进A375细胞凋亡,而对裸鼠则无明显的不良反应.     

云南省宁蒗县不明原因猝死病例调查研究

目的探讨云南省宁蒗县不明原因猝死病例的死因。方法对云南省宁蒗县不明原因猝死病例进行现场流行病学调查,采集样本进行病理学、病毒学等相关检验及分析研究。结果猝死病例的临床表现类似阿-斯综合征发作,心电图示窦性心动过速、Q-T间期延长、ST段改变、室颤,病理检验主要以心肌间质水肿、弥漫性炎细胞浸润、心肌纤维断裂、心肌灶性坏死以及其他脏器炎细胞浸润等改变为主;同发病例的临床表现亦类似阿-斯综合征发作,心电图示Q-T间期延长、室扑,粪便标本病毒分离阴性,但是从中检测到了埃可病毒11型(ECHO11)的基因片段。结论猝死病例及同发病例与既往报道的云南地方性爆发性心肌炎类似,心肌炎性改变可能诱发快速心律失常,引起阿-斯综合征发作,最后导致发病甚至猝死。     

弥漫性大B细胞淋巴瘤中CD40L的表达及意义

目的探讨弥漫性大B细胞淋巴瘤（DLBCL）组织中CD40L表达与DLBCL预后间的关系及意义。方法免疫组织化学法检测27例弥漫性大B细胞淋巴瘤、20例淋巴结反应性增生组织中CD40L的表达。结果（1）DLBCL中CD40L过度阳性率（25．93％）显著低于淋巴结反应性增生（63．64％），P〈0．05。（2）CD40L在Ⅲ、Ⅳ期DLBCL过度阳性率（14．29％）低于Ⅰ、Ⅱ期（38．46％），P〈0．05。CD40L过度阳性率在有结外浸润DLBCL（11．76％）低于无有结外浸润DLBCL（40％），P〈0．05。（3）DLBCL患者CD40L的过度阳性率与远处转移、临床分期均显著相关，P〈0．05。结论（1）CD40L过度阳性率与结外器官浸润及临床分期密切相关，其可能作为判断DLBCL侵袭性及预后的指标。（2）DLBCL中CD40L表达的减少可能是影响其发病的因素之一。     

结核分枝杆菌Rv1009基因蛋白的克隆和表达

目的 克隆表达结核分枝杆菌促Rv1009基因,序列测定正确后进行融合、表达.方法 采用热启动聚合酶链反应（Polymerase Chain Reaction,PCR）从结核分枝杆菌H37Rv基因组中扩增出Rv1009编码基因,用限制性内切酶消化后插入pGEX 4T-2载体中,将重组质粒转化大肠杆菌BL21（DE3）,目的基因经IPTG诱导,表达Rv1009基因蛋白.结果 经PCR扩增在1300bp处发现一条目的片段,获得了结核分枝杆菌H37Rv株Rv1009基因蛋白,经诱导后高效表达分子量为64KD的外源蛋白,与预期分子量大小一致,凝胶自动扫描分析,在A600值为0.6,IPTG终浓度为0.3 mmol/L,诱导表达3 h时融合蛋白表达量即达峰值,占菌体总蛋白的22.8%.结论 构建了结核分枝杆菌Rv1009基因重组表达载体,获得了RPF样融合蛋白的高效表达,为今后深入研究奠定了基础.     

中风后癫痫的临床研究

本文报告３６例中风后癫痫发作的临床和ＣＴ资料。通过回顾性病历复习和随访发现，中风后癫痫的发生率占同期住院中风患者的５．２６％，以蛛网膜下腔出血和脑栓塞发生癫痫比率最高，分别为１５％和１２．５％。癫痫发作与ＣＴ所见病灶分布密切相关，皮质病灶较皮质下病灶更易发生病病。癫痫发作可发生于中风后任何时期，但早期癫痫以出血性中风多见，而迟发性癫痫则更多见于脑梗塞患者。