剂量分布比较中γ因子的快速计算方法

γ比较方法作为放射治疗剂量学验证中的一种手段,现在已经在科研和临床的剂量分布比较中得到广泛应用。但是,在比较三维剂量分布时,γ因子的计算量大,需要花费大量的时间。本文采用一种预先排序技术和基于图形处理器(GPU)的并行计算技术结合,实现了γ因子的快速计算。通过7对剂量分布的测试,基于GPU的γ因子的计算速度提高了几十倍,而且与CPU相比保持了相同的计算精度。实验结果表明,利用GPU的并行计算对γ比较方法进行加速是切实有效的。     

睾丸大细胞钙化性支持细胞瘤一例

患者男．25岁。双侧睾丸肿大半年余,伴咳嗽、咳痰和发热于2005年3月入院。体检：双侧睾丸上极均触及无痛性硬肿物,大小分别约1．5cm×1．5cm和0．5cm×0．2cm,可活动,与周围组织无粘连．既往无睾丸外伤史,无体态及毛发的改变。无明显内分泌疾病症状和体征。手术切除双侧睾丸肿物,病理检查：两块肿物组织境界清楚,直径分别约1．5cm和0．5cm。切面为黄白色带有分散的钙化点,切开时有沙砾感.未见包膜的浸润．也无出血和坏死灶。镜下观察：肿瘤内钙化十分显著,瘤细胞排列呈小梁状、小管状和实体性区域,呈巢状分布（图1）。间质部分为疏松的黏液样基质,部分为纤维性间质,伴有形状不规则的钙化灶（图2）。瘤细胞胞体和细胞核均较大,可见明显的核仁和丰富的嗜酸性胞质。胞质内可见不规则的深红染小体样结构。核分裂象罕见。瘤细胞问可见少量淋巴细胞浸润。未见包膜和血管浸润．也未见Reinke结晶和脂褐素沉积。免疫组织化学染色示瘤细胞S-100蛋白和α-抑制素弥漫强阳性（图3,4）,波形蛋白阳性。但平滑肌肌动蛋白（SMA）、细胞角蛋白（CK）、甲胎蛋白（AFP）、Ki-67阴性。     

Expression of myelin and lymphocyte protein (MAL) in oral carcinogenesis

In the pathological diagnosis of oral squamous cell carcinoma, we often confront the difficulty of determining whether it is invasive carcinoma or epithelial dysplasia. Recently, myelin and lymphocyte protein (MAL; T-cell differentiation-related gene) has been reported to be a candidate gene suppressed in esophageal carcinoma. When we performed cDNA microarray analysis, we found that gene expression of MAL was significantly downregulated in oral squamous cell carcinoma (OSCC). We evaluated the expression of the MAL gene by laser microdissection and real-time PCR methods and protein localization by immunohistochemistry. The gene expression of MAL was significantly decreased in OSCC compared with normal epithelium (P < 0.05). Furthermore, protein expression of MAL disappeared gradually in proportion to malignancy. The results suggest that MAL plays an important role during oral carcinogenesis and that the gene may have potential as a biomarker target for OSCC.     

The investigation for the relationship among serum leptin,erythrocyte membrane Ca2+-ATPase activity and hypertensive disorder complicating pregnancy

Objective: To study the significance of Leptin and the activity of erythrocyte membrane Ca2+-ATPase (EMCA) in the development of hypertensive disorder complicating pregnancy. Methods: Radioimmunoassay was used to test the level of serum Leptin,and the activity of EMCA was determined chemically in 38 pregnant women with hypertensive disorder complicating pregnancy and 36 normotensive pregnant women. Results: The level of serum Leptin in hypertensive disorder complicating pregnancy(gestational hypertension: 13.76 ± 3.46 ng/ml; preeclampsia:15.76 ± 5.47 ng/ml; eclampsia: 18.32 ± 6.38 ng/ml)was significantly higher than that in normotensive pregnant women (11.33 ± 2.93 ng/ml), respectively. The average EMCA activity of patients with hypertensive disorder complicating pregnancy (gestational hypertension: 1.65 ± 0.24 μmol· pi/mg·h; preeclampsia: 1.37 ± 0.19 μmol·pi/mg·h; eclampsia:1.12 ± 0.14 μ mol·pi/mg·h) was significantly lower than that of normotensive pregnant women(1.83 ±0.38 μ mol·pi/mg·h),respectively. There was a negative correlation between the level of serum Leptin and the activity of RMCA in hypertensive disorder complicating pregnancy (r = -0.63). Conclusion: Inhibition of EMCA activity of erythrocyte in hypertensive disorder complicating pregnancy may increase cytoplasmic free calcium, which contributes to the development of hypertensive disorder complicating pregnancy. The negative correlation between the level of serum Leptin and the activity of EMCA, also suggested that serum Leptin and the activity of EMCA may play a role in the development of hypertensive disorder complicating pregnancy.     

Herbert螺钉联合带蒂桡骨骨瓣移植治疗腕舟状骨骨不连

目的探讨Herbert螺钉联合带血管筋膜蒂桡骨茎突骨瓣治疗腕舟状骨骨不连的临床疗效。方法采用Herbert螺钉固定联合带血管筋膜蒂桡骨茎突骨瓣治疗我院骨科自2010年9月~2016年1月收治的腕舟状骨骨不连患者25例。结果所有的患者平均随访5~24个月,骨折均愈合,骨折愈合时间是(12.7±2.1)周,使用改良Mayo腕关节评分评价腕关节功能,优秀16例,良好5例,一般3例,较差1例。结论对于腕舟状骨骨不连的患者,Herbert螺钉联合带血管筋膜蒂桡骨茎突骨瓣治疗腕舟状骨骨不连是一种有效且可行的方法。     

由测量驱动的蒙特卡罗模拟虚拟源的参数选择

基于蒙特卡罗(MC)方法的剂量计算算法已被普遍认为是可以在放射治疗中使用的最精确的计算工具。放射治疗中的MC模拟可分成两个部分,即对源的模拟和对实际患者的模拟。本文使用测量数据驱动的虚源模型建立了模拟直线加速器治疗头的虚拟源,通过与三维水箱中的测量数据比较,研究了虚拟源各种参数选择与计算精度之间的关系,表明考虑了初始光子源和次级光子源的综合影响,并选择合适的各种参数,由虚拟源出发的水模中的MC剂量分布可以与测量结果相一致,从而满足临床MC模拟的建模要求。     

吗啡成瘾小鼠对正常小鼠学习记忆力能力的影响

目的:用BALB/C小鼠建立动物模型,观察吗啡成瘾戒断小鼠对其周围的正常小鼠学习记忆能力的影响。方法:将吗啡成瘾戒断小鼠与正常小鼠同笼饲养,然后用Morris水迷宫实验测定正常小鼠的学习记忆能力,应用RT-PCR的方法检测正常小鼠海马中PKCa、GABA分子表达的变化。结果:水迷宫实验证明,与生理盐水组相比,实验组小鼠的学习记忆能力明显降低(P<0.05),海马中PKCa和DABA的表达都明显升高(P<0.05)。     

三维重建上肢解剖结构的计算机模拟手术

探索三维重建后计算机模拟手术过程的实现。将上肢新鲜标本经ＣＴ扫描后连续切片,把ＣＴ图像和大体断面图像同时输入计算机,用Ｂｏｒｌａｎｄ Ｃ＋＋语言编制三维重建和模拟手术程序,建立上肢三维解剖数据模型,将临床实际手术操作过程转化为计算机可接受的指令,实现模拟手术操作。结果表明：上肢模拟手术可分三段进行,手术部位及切口方向可任意选择,逐层“切开”并三维显示,因此,模拟手术系统可运用于手术方案的设计、选择     

Phylogeny of Vibrio cholerae based on recA sequence

We sequenced a 705-bp fragment of the recA gene from 113 Vibrio cholerae strains and closely related species. One hundred eighty-seven nucleotides were phylogenetically informative, 55 were phylogenetically uninformative, and 463 were invariant. Not unexpectedly, Vibrio parahaemolyticus and Vibrio vulnificus strains formed out-groups; we also identified isolates which resembled V. cholerae biochemically but which did not cluster with V. cholerae. In many instances, V. cholerae serogroup designations did not correlate with phylogeny, as reflected by recA sequence divergence. This observation is consistent with the idea that there is horizontal transfer of O-antigen biosynthesis genes among V. cholerae strains.     

内镜治疗慢性胰腺炎合并胆总管良性狭窄22例

目的:探讨内镜在治疗慢性胰腺炎合并胆总管良性狭窄中的临床应用价值.方法:回顾性分析2005-01/2009-09内镜治疗慢性胰腺炎合并胆总管良性狭窄患者22例的临床疗效.结果:22例患者共行内镜治疗35次,平均1.59次/人,操作成功率95.5%(21/22),1例治疗失败行外科手术治疗.并发症发生率为22.7%(5/22),其中急性胰腺炎1例,术后高淀粉酶血症3例,轻度胆管炎1例.22例患者中14例治疗后腹痛消失或明显减轻,所有治疗后复查肝功能指标均有明显改善.结论:内镜治疗慢性胰腺炎合并胆总管良性狭窄是一种安全、微创、有效的方法.