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61.
近红外线乳腺扫描对诊断乳腺癌,特别对早期乳癌具有高度的敏感性和诊断特异性,根据1500例证实的分析,近红外线乳腺扫描诊断率T1—T2期为95%;T1期直径<1cm及TO期乳癌诊断率为85%。 作者首先提出近红外线乳腺扫描的所见15种分型,本文叙述了近红外线乳腺检查的诊断原则及其诊断价值。 由于近红外线乳腺扫描具有高敏感性而且是无损害的简易的检查方法,我们认为应作为乳腺的常规检查及普查时的首选检查方法。  相似文献   
62.
麦胚提取物对辐射损伤修复的实验研究   总被引:2,自引:1,他引:1  
目的 研究麦胚提取物对小鼠辐射损伤修复的调节和保护作用。方法 采用辐射前或辐射同时饲喂一定量的麦胚提取物,观察小鼠经X射线一次性全身照射后的临床症状、30d存活率、骨髓微核率、外周血白细胞总数在不同时间的变化。结果 与对照组(单纯照射)比较,饲喂麦胚提取物可使小鼠的头面部皮肤、小肠黏膜、肾脏损伤症状得到明显改善;30d存活率为86.17%(P<0.01),提高存活率41.79%,保护系数为1.72;骨髓微核率4.62‰;比对照组(12.14‰)降低(P<0.01);外周血白细胞总数在7,13,20,30d均显回升(P<0.05,P<0.01,P<0.01,P<0.01)。结论 麦胚提取物对小鼠辐射损伤修复有一定程度的调节和保护作用,对于辅助肿瘤放射治疗具有重要意义。  相似文献   
63.
目的观察一例大剂量全身极不均匀照射急性放射损伤患者数处局部病理改变。方法病理常规切片染色,光镜检查。结果吸收剂量右下肢为3738Gy,左手掌为830Gy,于照射后第8天行右下肢、左前臂截肢术。右手、左膝照射剂量相对较小但难以准确估计,红斑、水肿、水疱、溃疡出现相对较晚,于第55天行右手指、左膝清创植皮术。镜下:右小腿局部皮肤和皮肤附属器官、皮下组织和骨胳肌广泛地坏死和弥漫性出血,但真皮中的立毛肌尚存;左手指、手掌皮肤表皮细胞空泡变性、坏死,并形成大小不一的囊泡,致使表皮与真皮分离,真皮弥漫性出血、中性粒细胞浸润,汗腺上皮细胞变性、坏死,皮下组织内弥漫性出血,少数脂肪细胞坏死。胫骨、腓骨上端和股骨、桡骨、尺骨下端处骨髓腔内造血组织各系细胞均消失。左膝、右手拇指、食指、中指皮肤示急性放射性溃疡。结论大剂量照射导致的急性放射损伤造成大面积、深达肌肉的软组织坏死及骨髓造血细胞消失。  相似文献   
64.
本文介绍了用实验方法研究不同管电压, 钢板厚度与散射线之间的关系.结果表明, 透射比随管电压升高而增加, 并随钢板厚度增加而下降;散射比随散射角的增大而逐渐下降, 至180°时为最低值。此研究为X射线探伤作业的辐射防护提供了依据。  相似文献   
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We report on two cases of women with locally advanced squamous cell carcinoma of the urethra. Patient 1 also displayed regional lymph node metastasis. Treatment comprised combined radiotherapy to 60 Gy and chemotherapy with 5-fluorouracil and cisplatin. Complete response was obtained in both patients, including the inguinal lymph nodes of Patient 1. Patient 1 experienced recurrent inguinal lymph node metastasis on the contralateral side at 42 months after initial treatment, and the same treatment was performed followed by surgical excision. Both patients remain alive with no evidence of disease, at 12 months after recurrence in Patient 1, and at 27 months after treatment in Patient 2.  相似文献   
68.
A 42-year-old female presented with subarachnoid hemorrhage (SAH), presumably from a radiation-induced anterior communicating artery aneurysm. Six years earlier, she had undergone radiation treatment for an optic glioma that was diagnosed based on imaging criteria. The aneurysm was successfully clipped, and the optic glioma was biopsied to verify the diagnosis histologically. Radiation-induced cerebral aneurysms often manifest with a fatal SAH. These aneurysms typically develop in the field of radiation and are diagnosed a mean of 8.52 years after radiation. Rarely, the aneurysm sac thromboses spontaneously. Clipping or coiling of the aneurysm can be an effective treatment.  相似文献   
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Summary A series of in vivo experiments were undertaken, relating functional (motor activity, body temperature), dopamine (DA) receptor binding and neurochemical (catecholamine synthesis and utilization, DA release) aspects of the pharmacology of SCH 23390 in the rat.The compound inhibited the locomotor hyperactivity, but not the hypothermia, induced by the potent DA stimulant DP-5,6-ADTN. Interstingly, SCH 23390 simultaneously failed to displace DP-5,6-ADTN from its binding sites in the rat striatum—used as a direct in vivo biochemical index of DA (D-2) receptor interaction. The spontaneous locomotion in non-pretreated rats was likewise inhibited by SCH 23390. The locomotor-suppressive action, but not the DP-5,6-ADTN-displacing capcity of the D-2 blocker haloperidol was significantly enhanced by SCH 23390, suggesting that motility can be suppressed by either enhanced D-1 or D-2 (postsynaptic) receptor blockade, but also that the D-1 and D-2 sites involved may be physically distinct.SCH 23390 only slightly altered in vivo neurochemical of DA synthesis, release and nerve-impulse flow, indicating that, while similar in suppressing dopaminergic behaviour, the D-1 antagonist is less effective than traditional neuroleptics as an activator of DA neuronal feedback mechanisms. The weak increases of DA synthesis and release nonetheless obtained were equal in magnitude (30–40%) in the limbic vs. striatal brain areas; also in this respect, SCH 23390 thus differs from classical neuroleptics, which generally display more marked effects in the striatum than in limbic tissue.No major changes in the in vivo indices of NA synthesis and utilization (or in 5-HT synthesis) were found after SCH 23390 administration, by and large supporting the DA receptor specificity of the compound.In summary, the studies demonstrated that SCH 23390 can offset and accentuate, respectively, behavioural consequences of D-2 receptor stimulation and blockade. Importantly, at the same time no direct interaction at the level of D-2 DA receptor sites in the striatum was detected. Only slight, D-2 antagonist-like, changes in neurochemical indices of dopaminergic activity were observed after D-1 receptor blockade by means of SCH 23390. With regard to DA agonist hypothermia, SCH 23390 was without effect per se, but (at a high dose) attenuated the action of the D-2 antagonist haloperidol. The observations may indicate that the complex interactions between central D-1 and D-2 receptor-controlled mechanisms that influence behaviour, neurochemistry, and possibly autonomic nervous expression, are not identical.  相似文献   
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