核黄素等抗甲基苄基亚硝胺的致细胞突变作用

采用ＣＨＯ细胞ＨＧＰＲＴ位点突变测定系统观察了核黄素、尼克酰胺和锌等微量营养素对甲基苄基亚硝胺（ＭＢＮＡ）致细胞突变作用的影响。结果表明，在ＲＰＭＩ１６４０培养基中添加核黄素（２．６～１３．０μｍｏｌ／Ｌ）或尼克酰胺（４０～１２０μｍｏｌ／Ｌ）可显著抑制ＭＢＮＡ的致细胞突变作用。联合应用核黄素、尼克酰胺和锌效果更佳。提示：核黄素等微量营养素可能具有阻止细胞癌变的作用，为应用微量营养素干预治疗癌变过程提供了一定的理论依据。     

髋臼骨折的手术治疗

目的：探讨髋臼骨折的手术治疗效果和影响疗效因素。方法：对31例髋臼骨折患进行切开复位由固定治疗。结果：平均随访18个月(6～36月)，根据Matta评分标准优16例，良8例，一般4例，差3例。1例术后发生深部感染，1例术后18个月发生股骨头坏死。结论：髋臼骨折，特别是有移位的髋臼骨折应及时手术治疗。手术医师的经验、骨折类型、手术时机和入路会影响髋臼骨折的疗效。     

CO作用后大鼠肺血管细胞增殖和凋亡状况的研究

目的：通过研究CO和低氧作用后大鼠肺血管细胞增殖和凋亡状况，探讨低氧肺动脉高压的发病机制及防治措施。方法：应用免疫组织化学，原位末端标记及Western杂交等方法检测常压低氧大鼠肺血管壁细胞增殖，凋亡及c-myc基因的表达状况。结果：正常组，低氧和锡原卟啉组，低浓度CO和血晶素组大鼠肺动脉均存在增殖和凋亡的阳性细胞，两类细胞在肺内呈不均匀散在分布，低氧和锡原卟啉组大鼠肺血管增殖细胞数显著升高而凋亡细胞数显著减少，细胞增殖凋亡比值分别为对照组的5倍或4倍，而低浓度CO和血晶素组肺血管增殖细胞和凋亡细胞系数均显著增加，细胞增殖凋亡比值均为1．2，c-myc在低氧和锡原卟啉组大鼠肺内表达显著增加，在低浓度CO和血晶素组大鼠肺内表达减少。结论：增殖和凋亡现象共存在于正常和处理大鼠的肺血管细胞中，也许c-myc等基因的异常表达导致了细胞增殖和凋亡的失衡，进而调节了慢性低氧肺血管结构的改建。     

林县冬贮菜中亚硝酸盐及维生素C的含量分析

对林县食管癌高发区两种冬贮菜中亚硝酸盐和维生素C的动态分析,表明亚硝酸盐含量随蔬菜冬贮时间延长而增加,维生素C含量则逐渐降低,两者成负相关。提示蔬菜冬贮过程中应尽量减少维生素C的破坏。     

Anatomic and spiral computed tomographic study of the genial tubercles for genioglossus advancement.

OBJECTIVE: To measure and compare Chinese mandibular genial tubercles measured anatomically and with computed tomography (CT). STUDY DESIGN AND SETTING: Spiral CT scans were taken of 40 adult human skulls; the superior genial spines were measured using anatomic and CT methods. RESULTS: The height and width of the superior genial spines, mandible thickness, and distance from the menton to the inferior and superior margins of the superior genial spines were 5.82 +/- 0.71, 6.98 +/- 1.35, 11.95 +/- 1.59, 11.08 +/- 2.05, and 16.91 +/- 2.30 mm from anatomic measurements and 6.17 +/- 0.71, 7.01 +/- 1.13, 12.19 +/- 1.64, 10.41 +/- 1.55, and 15.73 +/- 2.12 mm using spiral CT, respectively. The anatomic and CT measurements were correlated. CONCLUSION: Spiral CT of the genial tubercles can help locate the osteotomy in genioglossus advancement. SIGNIFICANCE: This study acquired reference data on Chinese genial tubercles demonstrating that CT measurements of the genial tubercles reflect their anatomy, which should allow accurately locate the osteotomy.     

Experimental studies of electroacupuncture on ventricular fibrillation threshold in rats with acute ischemic myocardium

Summary By ligating the proximate left anterior descend (LAD) of coronary artery and inducing the ventricular fibrillation with electrical stimulation, the preventive effects of electroacupuncture (EA) on ventricular fibrillation were observed. The results showed that the ventricular fibrillation threshold (VFT) of rats with acute ischemic myocardium was raised after acupuncturing some acupoints, which could prevent the occurrence of ventricular fibrillation. Furthermore, the combination of EA and propranolol could enhance the VFT effectively, and they showed a good synergistic effect. This project was supported by grants from National Natural Science Foundation of China (No. 3870563).     

A STUDY ON DETECTION OF SERUM FASTING TOTAL BILE ACID AND CHOLOYGLYCIN IN NEONATE FOR CHOLESTASIS

ＡＳＴＵＤＹＯＮＤＥＴＥＣＴＩＯＮＯＦＳＥＲＵＭＦＡＳＴＩＮＧＴＯＴＡＬＢＩＬＥＡＣＩＤＡＮＤＣＨＯＬＯＹＧＬＹＣＩＮＩＮＮＥＯＮＡＴＥＦＯＲＣＨＯＬＥＳＴＡＳＩＳＧｕｏＷｅｎ（郭文）；ＷｕＭｉｎｇｃｈａｎｇ（吴明昌）；ＰｅｉＸｕｅｙｉ（裴学义）；Ｇ...     

Differentiation-induced ML-1 cells as targets for transformation by a chemical carcinogen

The capacity for continuous proliferation (immortalization) of ML-1 human myeloblastic leukemia cells derives from their sensitivity to growth factors and their insensitivity to differentiation factors (DF) at the limiting concentrations at which these are present in the culture medium. Upon increasing the concentration of DF, or after treatment with DNA-specific anticancer agents, the cells exit the proliferation program and differentiate to monocyte/macrophage-like cells (Y. Honma, C. Honma, and A. Bloch, Cancer Res., 46: 6311-6315, 1986). The study reported here shows that when ML-1 cells, induced to differentiate with DF contained in mitogen-stimulated human leukocyte-conditioned medium (CM) are treated with the carcinogen N-nitroso-N-methylurea, their differentiation program is interrupted and proliferation is resumed at a stably increased rate of growth (doubling time, 25.1 versus 31.3 h). This "step-up" transformation is brought about by only a narrow concentration range of carcinogen, acting at a restricted time interval following differentiation induction. The step-up transformed cells are more sensitive to growth factor signals and less sensitive to DF signals than are untreated ML-1 cells. When retreated with a higher concentration of DF and the same concentration of N-nitroso-N-methylurea, the transformed cells undergo a further decrease in doubling time to 21 h. Differentiation-uninduced ML-1 cells do not respond to treatment with N-nitroso-N-methylurea, indicating that differentiation-induced cells, at an early stage of the maturation process, may be the targets for the carcinogen-mediated transformation.     

儿童生殖细胞瘤全脑放射治疗中自适应消除摆位累积误差新技术探讨

目的 以影像引导放射治疗(image guided-radiotherapy, IGRT)为基础探讨儿童生殖细胞瘤全脑自适应放射治疗(以下简称放疗）(adaptive radio therapy,ART）可行性,为临床全脑ART提供依据。方法 回顾性研究首都医科大学附属北京天坛医院放射治疗科20例中枢神经系统生殖细胞肿瘤(germ cell tumors, GCTs)行全脑预防性照射的放疗患者。每例患者治疗前三次及后每周行一次锥形束电子计算机断层扫描(cone beam computed tomography,CBCT),共7次。记录整个治疗过程中左右(lateral, LAT)、进出(longitudinal, LNG)、升降(vertical, VRT)方向上的摆位误差值。原计划命名为Plan_A,将因摆位误差值产生新的治疗中心点(treatment center point,ISO)回归治疗计划系统,不改变射野权重、射野分布情况下进行体积剂量计算,用Plan Sum功能相加摆位累积误差产生新计划得到Plan_B。将摆位累积误差产生的新计划用Acuros XB算法重新快速优化后用Plan Sum功能相加得到Plan_C。对比Plan_A、Plan_B、Plan_C的靶区及危及器官(organ at risk, OAR)剂量变化并用Wilcoxon配对符号秩检验证统计学差异。结果与Plan_A相比,Plan_B 均匀性指均匀性指数（homogeneity index, HI）95计划靶区（planning target volume, PTV）、 HI98 PTV为1.058 4~1.084 7。适形度指数(conformity index, CI）PTV为0.934 4。 临床靶区（clinical target volume, CTV）D_min相对偏差为－7.22%,P值为0.000 7。OAR相对偏差为－0.1%~9.8%。与Plan_ A相比,Plan_ C的HI95 PTV、 HI98 PTV为1.056 9~1.078 8。CI PTV为0.936 5。CTV D_min相对偏差为－1.69%,P值为0.545 9。OAR相对偏差为－0.15%~3.40%。结论儿童生殖细胞瘤全脑放疗摆位累计误差对靶区及危及器官剂量差异有统计学意义,摆位累计误差导致靶区均匀性及适形度变差,CTV的D_min 变化超过5%,OAR受量增高。ART再计划可以让靶区均匀性和适形度及危及器官受量接近原计划。同时Plan_B虽然存在相对偏差,但是危及器官的绝对剂量在合理范围内。