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麦冬类中药组织切片计算机三维重建图鉴   总被引:9,自引:0,他引:9  
利用计算机技术实现麦冬类中药组织连续切片三维重建与动态显示,为计算机辅助生药学鉴定和教学提供了新的三维图像技术和研究资料。  相似文献   
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用混合粘合剂碳糊电极测定丁螺环酮   总被引:6,自引:1,他引:5  
用混合粘合剂碳糊电极测定丁螺环酮张正奇,曾鸽鸣,刘传桂,黎艳飞(湖南大学化学化工系,长沙410082)碳糊电极无毒,制作方便,表面更新容易,应用电位范围广,在药物分析中已有应用[1~5]。我们在液体石腊中加入添加剂,组成混合粘合剂,可显著改善电极的检...  相似文献   
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In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications.  相似文献   
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Different responses of retinal ganglion cells to iontophoretically applied NMDA receptor antagonists and non-NMDA receptor antagonists were studied in anaesthetized cats. Cells with normal range of spontaneous firing and those with abnormally high spontaneous firing levels showed a different response to these drugs. Both visually driven and spontaneous firing of cells with 'normal' spontaneous firing level were blocked by non-NMDA receptor antagonists, but not by NMDA receptor antagonists which often raised spontaneous firing. In contrast, the responses of cells with abnormally high spontaneous firing level were blocked effectively by NMDA antagonists including MK-801, an NMDA channel blocker, as well as by non-NMDA receptor antagonists. The results suggest that under normal physiological conditions, NMDA receptors which are not involved in synaptic transmission may play a role in reducing the resting discharge level of the retinal ganglion cells. NMDA receptors, however, appear to open ion channels in response to glutamate input when ganglion cells become abnormally depolarized.  相似文献   
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ONE OF THE RISK FACTORS FOR HUMAN PAPILLOMAVIRUS (HPV) INFECTION and subsequent lower genital tract neoplasias and cancers is impaired cell-mediated immunity. HIV-positive women with severe immunosuppression are 5 times more likely than HIV-negative women to have lower genital tract neoplasias. A corresponding increase in the risk of invasive vulvar and anal cancers, but not of cervical cancer, has also been observed among HIV-positive women. Treatment failure and recurrence of neoplasia occur much more frequently among HIV-positive than among HIV-negative women. In this review, we discuss recent advances in the understanding of the relation between HIV and HPV coinfection and the development of lower genital tract neoplasias and cancers in women. In addition, we present strategies for monitoring and treating noninvasive and invasive neoplasias of the lower genital tract in HIV-positive women.  相似文献   
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Between 1974 and 1984, 173 patients were treated for squamous cell carcinoma of the tongue base. Fifty-four patients had T1 or T2 primaries, while 115 patients had T3 or T4 tumors (4 were not staged). Lymph node metastasis was present in 120 patients. Early primary tumors treated with surgery or radiotherapy had a control rate of 83% (5 of 6 tumors) and 89% (40 of 45 tumors), respectively. For advanced primary tumors, definitive radiotherapy produced a local control rate of 55% (42 of 76 tumors), compared with 79% (23 of 29 tumors) for surgery and postoperative radiotherapy. If primary control was obtained, the regional failure rate was less than 10%. Tumor growth patterns were predictive of the response to radiotherapy. The primary control rate at 2 years for 21 patients with exophytic tumors was 84% as opposed to 58% for 62 patients with ulcerative-infiltrative tumors (p = 0.04). Radiotherapy is effective for early stage or exophytic tumors, whereas for advanced or deeply invasive tumors combined therapy enhances local control.  相似文献   
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