Objective To explore the feasibility of children age dependent chest tube voltage settings for optimizing radiation dose and image quality in digital radiography (DR). Methods Children aged 0 to 14 who visited the First Affiliated Hospital of Xinjiang Medical University from January, 2008 to December, 2010, were divided into the following 5 age groups: 0~, 1~, 3~, 7~, and 11~14-year-old, and each group was then randomly assigned to the optimization and control groups to take DR by computer. DR in automatic exposure control with different tube voltage depending on children age; the control group: DR in automatic exposure control with conventional fixed tube voltage. The dose area product (DAP) was adopted for the measurement of radiation dose, while the visual grading analysis score (VGAS) was for image quality. Then SPSS 17.0 was applied for statistical analysis. Results A total of 2 450 children were initially included. Finally there were 2 415 children included in the anteroposterior chest image in this study, and the other 35 children were excluded for their anatomical characteristics could not be showed due to serious primary diseases. There were 1 202 patients in the optimization group and 1 213 patients in the controlled group. The mean DAP in the optimization group was lower than that in the control group with a significant difference (t= –4.967, P=0.008). The mean VGAS in the optimization group was higher than that in the control group with a significant difference (t= 23.738, P=0.000). Conclusion Children age dependent tube voltage settings can effectively reduce radiation dose and improve image quality at the same time.
【摘要】 目的 评价64层螺旋CT低剂量冠状动脉血管成像的价值。 方法 2009年1-6月157例患者随机分为3组，常规剂量组（A组）管电流量采用1 000 mAs，两个低剂量组（B、C组）分别采用800、600 mAs。对3组的图像质量、噪声、CT剂量指数（CTDI）、剂量长度乘积（DLP）和有效剂量（ED）进行评估。 结果 A、B、C组图像噪声分别为20.50±3.23、23.02±3.05和26.28±2.58，组间差异均无统计学意义（Pgt;0.05）；A、B、C组的CTDI分别为（58.7±0.23）、（46.98±2.27）、（35.28±3.56） mGy，DLP分别为（1 050.88±89.63）、（846.21±57.86）、（641.13±32.15） mGy?cm，ED分别为（14.78±2.56）、（11.85±1.87）、（8.98±1.15） mSv，B、C组的CTDI、DLP、ED均明显低于常规剂量A组（Plt;0.05），C组的CTDI、DLP、ED均为3组中最低值。 结论 64层螺旋CT冠状动脉血管检查，采用600 mAs管电流量获得的冠脉图像既可满足诊断需要，又可使患者接受的辐射剂量降低。【Abstract】 Objective To evaluate the best tube current for low-dose radiation CT in coronary artery imaging by 64-slices multi-detector CT. Methods From January to June 2009, a total of 157 consecutive patients were randomly divided into 3 groups: group A (conventional group): 1 000 mAs; group B: 800 mAs; group C: 600 mAs. The image quality, noise, CT dose index (CTDI), dose length product (DLP) and effective dose (ED) in each group were measured and compared respectively. Results The image noise scores in group A, B, and C were (20.50±3.23), (23.02±3.05) and (26.28±2.58), respectively. There was no statistically significant difference among the three groups in the two indexes (Pgt;0.05). The CTDI in group A, B and C were (58.7±0.23), (46.98±2.27), and (35.28±3.56) mGy, respectively; the DLP in each were (1 050.88±89.63), (846.21±57.86), and (641.13±32.15) mGy?cm, respectively; the Ed were (14.78±2.56), (11.85±1.87), and (8.98±1.15) mSv, respectively. All of the differences among the three groups in CTDI, DLP and ED were statistically significant (Plt;0.05). Conclusion The image with 600 mAs as tube current in the coronary artery imaging of 64-slices multi-detector CT could fulfill the need of the diagnosis, and the radiation dose is apparently lower than the conventional scan.
【Abstract】Objective To investigate the irradiating effect of low intensive microwave (LIM) on pathological process of blood vessel restenosis(RS) and assess the probability of LIM irradiation to prevent was used RS.Methods Fortyfour male healthy New Zealand rabbits were randomly divided into 2 groups. Fogarty catheter traumatize to the tunica intima of iliac artery so as to establish RS models. Two thousand four hundred and fifty MHz microwave with different power of 2 ,5 and 10 mW/cm2 was used, locally to irradiate EIA in irradiating group (1 h/d). Specimens were obtained at different time of 3,7,14 and 28 d after operation. Morphological changes of tissues were observed with HE and EF staining and the area of tunica intima, tunica media and the rate of cavity stenosis were analyzed with image analysis system; apoptosis was detected with TUNEL; phenotype and microstructure of VSMC were observed with TEM. Results After microwave irradiating, inflammatory reaction in early period was suppressed, mural thrombus decreased, the proliferation and migration of VSMC depressed, the area of tunica intima and the rate of cavity stenosis obviously reduced comparing with the control group (P＜0.01). The rate of apoptosis cells showed that there were no obvious differences among each group on 3 d after operation (Pgt;0.05). At other different time, however, the rate of apoptosis cells in irradiating groups obviously increased than that of the control group (P＜0.01), particularly in the one with power of 5 mW/cm2 .The number of synthesis form VSMC in the control group occupied (93.50±3.45)% of the total number of VSMC on 14 d after operation. Most of VSMC appear contractile in irradiating group in which a lot of morphological changes of apoptosis in fibroblast and VSMC existed.Conclusion LIM irradiation could obviously prevented from pathologic procedure of RS. After LIM irradiating, inflammatory reaction in early period is suppressed, the proliferation and migration of VSMC depressed. LIM irradiation promotes cell apoptosis, effectively prohibites the occurring and development of RS. LIM irradiation has had relationship between quantity and effect, power span to effectively prohibit RS, particularly in the one with power of 5 mW/cm2.
Objective To investigate the effects of ectomesenchymalstem cells on hematopoiesis after total body irradiation in rats. Methods The primary ectomesenchymal stem cells were isolated from E11.5 SD fetal mandibular processes by 25g/L trypsin and cultured with DMEM/F12. The morphology and growthrate were observed by inverted microscope. Eighty SD male rats randomly dividedinto ectomesenchymal stem cells group (n=20), fibroblast group(n=20), saline group(n=20) and control group(n=20), the first three groups were irradiated with 60Co γ rays at 6.0 Gy. The number of their bone marrow nucleated cells was counted after 4 weeks; the forming ability of colony-forming unit-granulocyte macrophage(CFU-GM) and histopathology of bone marrow were also observed. Results The cultured cells displayed monolayer growth and fibroblast-like with 2-4 processes. The ectomesenchymal stem cells could increase the number of bone marrow nucleated cells and peripheral blood white cell count, and improve the forming ability of CFU-GM. After 4 weeks of transplantation, the number of the peripheral blood white cells in group A was more than that in groups B and C(Plt;0.05), the contents of Hb in groups A and D was significantly higher than those in groups B and C(Plt;0.0). After 4 weeks, the bone morrow nucleated cells in group A were significant more than those in groups B and C(Plt;001); CFU-GM in groups A and D was higher than that in groups B and C(Plt;0.01). Conclusion Ectomesenchymal stem cells have characteristics of stem cells. It may improve hematopoiesis recovery of irradiated rats.
OBJECTIVE Influence of irradiation and phenytoin sodium on modulatory activities of wound fluid on proliferation of fibroblasts and collagen synthesis was studied. METHODS The male Wistar rats were used in this study. The rats were divided into irradiated and non-irradiated groups, and in each of them it was subdivided into phenytoin group and control. A 7 cm long incisional wound was made on the back of each rat, in which a polyvinyl alcohol sponge (PVAS) with a size of 1.0 cm x 0.4 cm was implanted into the wound and the wound was sutured up. The PVAS was prepared by rinsing in running water over night and then was boiled for 30 minutes. Before implantation, the sponge was immersed in phenytoin sodium solution (10 mg/l ml) or normal saline (as control). From each wound the wound fluid and fibroblasts were collected. The methods of incorporation of 3H were adopted to assess the proliferation of fibroblasts and synthesis of collagen. RESULTS It was shown that proliferation of fibroblasts and collagen synthesis were stimulated by wound fluid remarkably on 5 to 8 days after wounding, and that 6 Gy to total-body irradiation wound decrease this effect. It was also noted that topical phenytoin sodium increased the modulatory activity of wound fluid irrespective of being irradiated or not. CONCLUSION It could be drawn that, after total-body irradiation, stimulation of hyperplasia of fibroblasts and collagen synthesis by wound fluid was markedly lowered indicating the total-body irradiation resulted in changes of local conditions of the wound which was unbenefitted to repair of tissue cells, while phenytoin sodium could enhance the stimulating action of wound fluid on proliferation of fibroblasts and synthesis of collagen which was beneficial to wound healing.
Objiective To observe the changes of angioarchitecture of the optic disc in cats eyes after radial optic neurotomy (RON). Methods Ten healthy adult cats underwent unilateral RON randomly in 10 eyes as an operative group in this trial, and the fellow eyes (10 eyes) were as the control group. The colophony samples of vascular angioarchitecture of 20 eyes were made 90 days after RON and scanning electron microscope was used for the observation. Results In the control group, the blood supply of optic disc mainly came from the short posterior ciliary artery, pial artery, and retinal ciliary artery; the choroidal capillary vessels around the optic disc didnprime;t take part in the blood supply in the anterior area; retinal central vascular system and complete arterial circle around the optic nerves were not seen. In the operative group, a V-shaped defect of the optic disc, retinal blood vessels and choroidal capillary vessels was found at the surgical incision; no injury of retinal blood vessels and choroidal large vascular layer was seen, and neovascularization at the incision were not found. Conclusions RON may cause the vascular defect of the optic disc and the peripheral local tissues. The depth of the incision doesnprime;t reach the Zinn-Hallers circle. (Chin J Ocul Fundus Dis, 2007, 23: 170-172)
Objective To optimize image quality and radiation dose of infant chest digital radiography and to explore feasibility of reducing tube voltage and adjusting according to infant chest area. Methods 0 to 3-year-old infants were randomly divided into two average groups of 0- and 1-3 year-old, and then each age group was randomly assigned to optimization and control groups in digital radiography. Measurement of radiation dose used dose area product (DAP). Mean DAP between groups was compared by using t test, and the image quality of optimization was compared by rank sum test. Results A total of 400 cases of 0 to 3-year-old infants were identified, and finally 391 cases of infants anteroposterior chest image were included, including 196 cases in the optimization group (0-years: n=91; 1-3 years: n=105) and 195 cases in the control group (0-years: n=103; 1-3 years: n=92). The results showed: there were significant differences in the mean DAP in 0-years, 1-3 years and total infants between the optimization group and the control group (all P valuelt;0.05). The DAP of the optimization group was lower, and reduction of DAP was approximately 21.6% compared to the control subject. The Wilcoxon signed-rank test showed the difference of subjective evaluation of image quality was significantly different (P=0.000). High-quality image of the optimization group increased approximately 43.9% more than control subject. Conclusion Reducing tube voltage and adjusting according to infants chest area can not only reduce the radiation dose but also improve image quality in digital radiography.
目的 研究薏苡仁水提液对受辐射小鼠外周血白细胞、骨髓有核细胞数量及微核率变化的影响，并检测白细胞介素（IL）-1、IL-2、超氧化物歧化酶（SOD）基因的变化以探讨其抗辐射损伤的作用机制。 方法 用薏苡仁水提液在受辐射前后对小鼠进行灌胃，对辐射后小鼠外周血白细胞、骨髓有核细胞计数，计算微核率，逆转录-聚合酶链反应（RT-PCR）检测IL-1、IL-2、SOD基因的变化，对实验结果进行统计学分析。 结果 随薏苡仁水提液剂量的加大，受照射小鼠骨髓有核细胞数不断增多，且微核数呈降低趋势；高剂量组与空白对照组相比，照射后第7天小鼠外周血白细胞数差异无统计学意义（P＞0.05），且3个剂量组外周血白细胞数均高于辐射对照组，差异有统计学意义（P＜0.01）；薏苡仁水提液高、中剂量组IL-1、IL-2、SOD基因的相对表达量均高于空白对照组和辐射对照组（P＜0.01）。 结论 薏苡仁水提液可能具有促使骨髓有核细胞快速释放、加快外周血白细胞数量恢复进度的作用，且具有降低受辐射小鼠骨髓有核细胞和外周血淋巴细胞微核率的作用；再者，薏苡仁水提液可上调受辐射小鼠机体SOD、IL-1、IL-2的表达水平，具有增强自由基清除、抗辐射和免疫保护调节的作用。