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1.
Xiangdong Xie Guoshan Yang Hongmei Zhou Decheng Qu 《Journal of radiological protection》2006,26(3):301-308
An OUR-QGD gamma ray stereotactic body radiotherapy system (body knife), made in China, is described. According to its structure and the principle of gamma radiation revolved on a focus, the energy distribution of scattered radiation in its treatment room is calculated. The structural shielding of the wall, roof, and door for a certain treatment room is calculated according to the local radiation protection law. 相似文献
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对离体不同时间血痕进行肉眼和扫描电镜观察,获得了血痕形态结构变化的初步认识.结果随时间延长,血痕逐渐干燥、龟裂,电镜下纤维蛋白网消失,其超微结构变化观察有助于血痕经过时间的推断. 相似文献
3.
肺内小病灶CT表现及其病理基础的研究:附76例分析 总被引:9,自引:0,他引:9
本文对76例肺内小病灶(直径≤3cm)病例进行了CT-病理对照研究。结果表明,短毛刺征,深分叶征、棘状突起征、空泡征、血管集束征,胸膜凹陷征等对于诊断周围型小肺癌有重要临床价值;而尖角征、局限性胸膜肥厚粘连对诊断良性病灶有意义。本文重点讨论了血管集束征的定义,CT表现及病理基础;并就有争议的胸膜凹陷征提出一些粗浅的看法。旨在提高肺内小病灶良恶性诊断的准确率 相似文献
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人大肠癌不同转移潜能细胞株SW620及SW480的差异蛋白质组分析 总被引:2,自引:0,他引:2
6.
References: 《生殖医学杂志》2007,16(Z1):56-59
Objective To investigate the correlation between TNF-α and IL-6 levels in cervical mucous during follicular development and ovulation stimulation in different protocols.Methods 36 infertile women were set up as experimental groups,divided into CC, HMG, IVF-ET group,each group consisted of 12 infertile women and 15 women with normal menstrual cycles were choiced as control group.Cervical mucous during follicular phase, luteal phase and ovulation phase were collected.TNF-α, IL-6 levels in cervical mucous were measured by radioimmunology assay (RIA).Follicular development were monitored by transvaginal ultrasonagraphy.Results (1) TNF-α levels in cervical mucous of experimental groups and control group were periodically various among the reproductive cycle.It increased during follicular phase, reached to peak during ovulation phase, and decreased during luteal phase (P<0.05).IL-6 levels had no obvious periodical changes.(2) Compared with CC and control group, levels of TNF-α,IL-6 in HMG and IVF-ET group were significantly higher (P<0.05).(3) Levels of TNF-α and IL-6 in cervical mucous were positively correlated with the dominant follicle diameter (r=0.261, r=0.192 respectively,P<0.05).(4) TNF-α and IL-6 showed positive correlation in the reproductive cycle (r=0.782,P<0.05).Conclusions (1) TNF-α level shows a cyclic change in the reproductive cycle and peaks during ovulation,whereas IL-6 level does not.(2) TNF-α and IL-6 may play a certain role in the process of follicular development and ovulation.(3)The levels of TNF-α and IL-6 are up-regulated by gonadotrophic hormone.(4) TNF-α and IL-6 may have coordination properties and participate in the same biological effects. 相似文献
7.
BACKGROUND: Dendritic cell is the most major antigen presenting cell of organism. It is proved in recent studies that human umbilical cord blood mononuclear cells induced and cultured in vitro by recombinant human granulocyte-macrophage colony stimulating factor (rhG-MCSF) and recombinant human interleukin-4(rhIL-4) can generate a great many dendritic cells and promote the lethal effect of T cells on human neuroblastoma, but it is unclear that whether the lethal effect is associated with the most proper concentration of dendritic cells.
OBJECTIVE: To investigate the lethal effect of human umbilical cord blood mononuclear cells induced in vitro by cytokines differentiating into dendritic cells on human neuroblastoma, and its best concentration range.
DESIGN: Open experiment.
SETTING: Department of Pediatrics, the Medical School Hospital of Qingdao University.
MATERIALS: The study was carried out in the Shandong Provincial Key Laboratory (Laboratory for the Department of Pediatrics of the Medical School Hospital of Qingdao University) during September 2005 to May 2006. Human umbilical cord blood samples were taken from the healthy newborn infants of full-term normal delivery during October to November 2005 in the Medical School Hospital of Qingdao University, and were voluntarily donated by the puerperas. Main instruments: type 3111 CO2 incubator (Forma Scientific, USA), type 550 ELISA Reader (Bio-Rad, USA). Main reagents: neuroblastoma cell line SK-N-SH (Shanghai Institute of Life Science, Chinese Academy of Sciences), RPMI-1640 culture fluid and fetal bovine serum (Hyclone), rhIL-4 (Promega, USA), rhG-MCSF (Harbin Pharmaceutic Group Bioengineering Co.Ltd), rat anti-human CD1a monoclonal antibody and FITC-labeled rabbit anti-rat IgG (Xiehe Stem cell Gene Engineering Co.Ltd).
METHODS: ① Human umbilical cord blood mononuclear cells obtained with attachment methods differentiated into human umbilical cord blood dendritic cells, presenting typical morphology of dendritic cells after in vitro induction by rhG-MCSF and rhIL-4. ② Different concentrations of dendritic cells[ dendritic cells: neuroblastoma cells=20∶1,50∶1,100∶1(2×108 L-1,5×108 L-1,1×109 L-1)], 1×109 L-1 T cells and 1×107 L-1 neuroblastoma cells were added in the experimental group. 1×109 L-1 T cells and 1×107 L-1 neuroblastoma cells were added in the control group. ③ Main surface marker CD1a molecules of dendritic cells were detected with indirect immunofluorescence, and the percent rate of dendritic cells was counted with ultraviolet light and expressed as the expression rate of CD1a+ cells. ④ Single effector cells and target cells were respectively set in the experimental group and control group to obtain the lethal effect. The lethal effect of dendritic cells on neuroblastoma cells was indirectly evaluated by detecting cellular survival with MTT assay. The lethal effect(%)=(1-A experimental well-A effector cell well/A target cell well)×100%.⑤The experimental data were presented as Mean ±SD, and paired t test was used.
MAIN OUTCOME MEASURES: ① Morphological characters of dendritic cells in the process of induction and differentiation. ②CD1a+ cellular expression rate. ③Lethal effect of dendritic cells on neuroblastoma cells.
RESULTS: ①Morphological characters of dendritic cells in the process of induction and differentiation: On the 15th day after human umbilical cord blood mononuclear cells were induced by rhG-MCSF and rhIL-4, typical morphology of dendritic cells could be seen under an inverted microscope. ②Expression rate of CD1a+ cells was (43.12±5.83)%. ③Lethal effect of dendritic cells on neuroblastoma cells: Lethal effect of dendritic cells stimulated T cells in each experimental group ( dendritic cells: neuroblastoma cells=100∶1,50∶1,20∶1 respectively) on neuroblastoma cells was significantly higher than that in control group[(31.00 ±4.41)%,(30.92±5.27)%,(33.57±5.35)%,(26.23±5.20)%, t=3.51,2.98,4.24, P < 0.01); But the lethal effect of dendritic cells on neuroblastoma was significantly lower when their ratio was 100∶1 and 50∶1 in comparison with 20:1 (t=2.01,2.36, P < 0.05), and no significant difference in lethal effect existed between the ratio at 100∶1 and 50∶1(t=0.06,P > 0.05).
CONCLUSION: Dendritic cells differentiated from human umbilical cord blood mononuclear cells after in vitro induction of cytokines can promote the lethal effect of T cells on neuroblastoma cells. The lethal effect is associated with the concentration of dendritic cells within some range. 相似文献
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