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61.
目的 研究经肝动脉化疗栓塞 (THACE)治疗肝癌过程中 ,患者受到的X射线辐射 ,为THACE放射防护提供依据。方法 回顾性分析 82例HCC患者的辐射剂量资料 ,DSA机 (Angiostar Plus)配置穿透电离室型剂量监测系统 (DiamentorK1andDiamentorED) ,在线读取面积剂量乘积DAP(cGy cm2 )和入射表面剂量ESD(mGy) ,采用Monte Carlo转换因子估算有效剂量ED(mSv)。并分析近期 10例THACE患者 ,在提高基值管电压、减低透视脉冲频率和摄影帧数下对辐射剂量的影响。结果 82例HCC患者透视时间 (35 3± 2 1 1)min ,摄影 (2 34± 10 8)帧 ,DAP为 (2 174 8± 12 4 2 4 )cGy cm2 ,ESD为 (96 4± 6 32 )mGy ,ED为 (34 8± 19 9)mSv。透视对总DAP的贡献 (2 4 0± 12 7) %小于摄影 (75 9± 12 7) % ,透视对ESD值的贡献 (4 9 8± 14 9) % ,与摄影相似 (5 1 6± 14 2 ) %。近期的 10例THACE患者的每分钟透视剂量、每帧摄影剂量及总剂量都比HCC患者明显降低。结论 在THACE过程中患者受到一次性较大剂量X射线照射。适度提高基值管电压、减低透视脉冲频率和缩减摄影帧数 ,可以有效降低患者的辐射剂量 相似文献
62.
Anthony P Cullen Olanrewaju M Oriowo Anita C Voisin 《Clinical & experimental optometry》1997,80(3):80-86
Concern about short- and long-term ultraviolet radiation (particularly UVB) damage to the eye has led to increased research in this area. Numerous studies have confirmed the pathogenic enhancing roles of reflected ultraviolet (UV) and visible radiation in our environment. There is concern that conventional sunglasses do not protect the eye adequately from reflected rays (albedo), especially on the lateral aspect, from behind and from below. Using eye models and computer ray tracing methods, the pathways of oblique rays incident at the temporal peripheral cornea have been plotted by Maloof, Ho and Coroneo.1 These rays are refracted and focused and theoretically can result in up to 20 times the concentration of incident irradiance at the nasal anterior chamber angle and nasal equatorial cortex of the crystalline lens. The purpose of this study was to determine the limits of angular subtense of the incident peripheral light which is refracted in this manner in human subjects and to investigate the relation between corneal shape and certain ocular parameters to the limits. A statistically significant positive correlation was found between temporal entrance angle and anterior chamber depth (r = 0.70, P< 0.0006). The entrance angle ranged from 15 degrees to 30 degrees and was located 10 degrees to 45 degrees posterior to the coronal plane. Our results support Maloof and colleagues' predictions for the implication of focused peripheral UV and high intensity visible radiation in the pathogenesis of pterygium and cortical cataract and emphasise the need for lateral eye protection in conditions of high ultraviolet albedo. 相似文献
63.
Moshe Stein N. Haim Abraham Kuten Yafa Doron Yehudi T. Ben Arieh Yoram Cohen 《Journal of surgical oncology》1992,51(4):270-273
Thirty-three patients with primary gastrointestinal lymphoma (GIL) followed at Ankara University Medical School have been evaluated. The most frequent locations of the disease are the small intestine (48.4%) and the stomach (39.3%). The intermediate and high grade lymphomas constitute 84.8% of the cases. The mean age of the patients with small intestinal lymphoma is 28.7 years and 47.1 years for those with gastric lymphoma. The patients treated with surgery and chemotherapy (S+CT) have a longer survival than those treated with chemotherapy (CT) alone. In conclusion: 1) Small intestinal lymphoma occurs more frequently than gastric lymphoma in our study. 2) The median age of the Turkish patients with primary GIL is approximately 10 years less than those in the Western countries. 3) The therapeutic results of S+CT are superior to those of CT in the early stages of the disease. 相似文献
64.
ThedynamicdistributionofnitricoxidesynthaseinthesmallintestineofmicewithintestinalradiationsicknessWeiLichun(魏丽春);GuoYao(郭鹞)(... 相似文献
65.
Localized proton spectroscopy of inoperable brain gliomas. Response to radiation therapy 总被引:3,自引:0,他引:3
M. A. A. M. Heesters R. L. Kamman E. L. Mooyaart K. G. Go 《Journal of neuro-oncology》1993,17(1):27-35
Within vivo 1H-MRS resonances of several metabolites were simultaneously measured in cerebral gliomas and adjacent normal brain. 15 patients with inoperable brain gliomas all histologically verified were monitored with 1H-MRS and MRI before and after radiotherapy. 11 patients were evaluable. 1H-MRS technique evolved from single volume measurements to one dimensional and two dimensional 1H spectroscopic imaging. In all patients N-acetyl-aspartate signals were decreased in tumour areas compared to the normal brain hemisphere. No recovery was seen after radiotherapy. Choline signals were increased in tumour margins of high grade gliomas and more diffusely in low grade gliomas. In 5 patients the choline resonance decreased after radiotherapy, accompanied by a shrinkage of tumour diameter on MRI. Lactate signals were present in high grade and unspecified astrocytomas and absent in most low grade gliomas. In 3 patients the lactate signal disappeared after radiotherapy. These observations indicate the feasibility of 1H-MRS in monitoring metabolic responses on radiotherapy of brain gliomas. 相似文献
66.
以肝、脾组织中过氧化脂质(LPO)含量及谷胱甘肽过氧化物酶(GSHL-Px)活性为指标探讨硒的辐射防护效应。实验结果表明:BALB/C纯系雄性小鼠经3Gy ~(60)Co γ射线照射后3天,肝、脾组织LPO生成量比未照射者均显著增多,而GSH-Px活性却都显著降低;但于照射前连续7天每日经口灌胃亚硒酸钠溶液0.2ml(含硒12.5μg)的实验组动物,肝、脾组织LPO含量均明显少于照射对照组,而GSH-Px活性都显著高于照射对照组,结果提示,通过降低LPO含量和增加GSH-Px活性,硒对小鼠可能有辐射防护作用。 相似文献
67.
M. Fujioka M.D. K. Okuchi S. Miyamoto T. Sakaki S. Tsunoda S. Iwasaki 《Acta neurochirurgica》1994,131(3-4):265-269
Summary The authors describe a 66-year-old man with progressive gait disturbance caused by bilateral organized chronic subdural haematomas. The characteristics of these lesions on magnetic resonance (MR) images have not yet been clarified. The organized haematoma in our patient exhibited slight hypo-intensity on T 1-weighted MR images and marked hypo-intensity on T 2-weighted MR images obtained at 1.5 T. Preoperative MR imaging may give us useful information about surgical strategy in the case of chronic subdural haematoma with an unusual appearance on computed tomographic (CT) scans. 相似文献
68.
全身(全淋巴)照射后100例医源性急性放射病的临床分析 总被引:1,自引:1,他引:0
在造血干细胞移植治疗肿瘤过程中用全身照射(TBI)或全淋巴照射(TLI)预处理,研究受照不同剂量患者发生医源性急性放射病严重程度,治疗方法和造血恢复及相关合并症。方法100例患者(白血病91例,其他肿瘤9例)接受500~1000cGyTBI或TLI和超大剂量化疗作预处理。结果均发生医源性急性放射病,白细胞降至(0~0.15)×109/L,骨髓空虚,合并各种感染和出血。经造血干细胞移植,抗感染,应用GM-CSF或G-CSF积极支持治疗及保护隔离措施,92例造血恢复,8例死于不同感染和出血。结论造血干细胞的移植起主要治疗作用,不同造血因子用于治疗急性放射病,可能是一种有希望的方法 相似文献
69.
M. Matsutani M.D. O. Nakamura T. Nagashima A. Asai T. Fujimaki H. Tanaka M. Nakamura K. Ueki Y. Tanaka T. Matsuda 《Acta neurochirurgica》1994,131(1-2):80-90
Summary In radiation therapy for malignant brain tumours, the dose of radiation that can be safely delivered to a tumour is limited by the radiation tolerance of the adjacent normal brain tissue. Among various radiation modalities to produce local tumour eradication without unacceptable complications, we chose a large, single irradiation dose during the operation (intra-operative radiation therapy, IORT). In contrast to X-ray or Cobalt-60 gamma ray irradiation, IORT with a high-energy electron beam delivered by the Shimadzu 20 MeV betatron provides acceptable dose homogeneity with rapid fall-off of the radiation dose beyond the treatment volume. Thus, IORT has the advantage of precise demarcation of the target volume, minimum damage to surrounding normal tissues, and a high absorbed target dose (15–25 Gy in 5–10 min).On the basis of our experience with 170 patients treated by IORT, we established the treatment indications and method in patients with malignant brain tumours. IORT with a dose of 15–25 Gy was delivered to widely resected tumours followed by external radiation therapy. No acute or subacute complications were observed. Treatment results of 30 patients with glioblastoma treated by IORT (mean 18.3 Gy) combined with external radiation therapy (mean 58.5 Gy) resulted in a median survival of 119 weeks and a 2-year survival rate of 61%.Supported by a Research Grant for Cancer (3–46, 4–23) from the Ministry of Health and Welfare, and by a Grant-in-Aid for Scientific Research (03454343) from the Ministry of Education, Science and Culture of Japan. 相似文献
70.
Auditory Perception and the Control of Spatially Coordinated Action of Deaf and Hearing Children 总被引:1,自引:0,他引:1
G. J. P. Savelsbergh J. B. Netelenbos H. T. A. Whiting 《Journal of child psychology and psychiatry, and allied disciplines》1991,32(3):489-500
From birth onwards, auditory stimulation directs and intensifies visual orientation behaviour. In deaf children, by definition, auditory perception cannot take place and cannot, therefore, make a contribution to visual orientation to objects approaching from outside the initial field of view. In experiment 1, a difference in catching ability is demonstrated between deaf and hearing children (10-13 years of age) when the ball approached from the periphery or from outside the field of view. No differences in catching ability between the two groups occurred when the ball approached from within the field of view. A second experiment was conducted in order to determine if differences in catching ability between deaf and hearing children could be attributed to execution of slow orientating movements and/or slow reaction time as a result of the auditory loss. The deaf children showed slower reaction times. No differences were found in movement times between deaf and hearing children. Overall, the findings suggest that a lack of auditory stimulation during development can lead to deficiencies in the coordination of actions such as catching which are both spatially and temporally constrained. 相似文献