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491.
492.
NONMEM法分析临床病人静脉输注阿米卡星的群体药代动力学   总被引:3,自引:0,他引:3  
收集52例呼吸科感染病人静脉输注阿米卡星(amikacin,AMK)的临床数据,用荧光偏振免疫法(FPIA)测定临床病人AMK的血清浓度275点,按二房室开放模型,用NONMEM程序一步估算出AMK的群体药代动力学参数,并定量地分析病人的体重、肌酐清除率、长期用药和病理状况(慢性阻塞性肺病,COPD)等固定效应对药代动力学参数的影响。经统计分析病人的肌酐清除率和COPD对AMK的药代动力学参数的影响有显著意义,而体重对表观分布容积Vc的影响无显著意义。由最终回归模型估算出AMK的群体药代动力学参数。  相似文献   
493.
Bonakdarpour  A; Levy  WM; Aegerter  E 《Radiology》1978,126(1):75-83
Radiological findings in 75 cases of aneurysmal bone cyst were analyzed. Sixty-five per cent were primary or simple and 35% were secondary, the aneurysmal bone cyst being combined with other osseous lesions. A primary aneurysmal bone cyst can be diagnosed with a high degree of certainty, but only 20% of secondary forms had the radiological appearance of aneurysmal bone cyst; in the other 80% the associated lesion dominated the radiological picture, particularly when it was malignant. In the secondary form a small biopsy specimen may show the features of aneurysmal bone cyst only; without radiological assistance a concomitant malignant lesion may be missed. Therefore, there must be close collaboration between the radiologist and and the pathologist.  相似文献   
494.
Radiotherapy for verrucous carcinoma   总被引:3,自引:0,他引:3  
  相似文献   
495.
The exposure of human circulatory white cells in vitro to 0.1-1-10 mol/l hydroxyurea (HU) for 20 h induced a progressive dose-dependent suppression of the phagocytic activity of granulocytes. The suppressing effect of 20 h exposure to 1 mol/l HU was used to examine the protection afforded by free radical scavengers against HU-induced cytotoxicity. It has been found that, in the suitable concentration of the protecting agent, a substantial protective effect of sodium benzoate, acetylosalicylic acid, alpha-tocopherol, ascorbic acid, catalase, peroxidase or superoxide dismutase can be achieved.  相似文献   
496.
云南红豆杉枝叶中一个新成分的结构鉴定   总被引:2,自引:0,他引:2  
从云南红豆杉(Taxus yunnanensis ChengetL.K.Fu)枝叶的二氯甲烷提取部分得到一个新化合物紫杉云亭(taxayuntin),经光谱分析和单晶X-射线衍射推定其结构为5/7/6元环和环氧丙烷四元环稠合的紫杉烷类化合物。这种骨架的紫杉烷二萜化合物在红豆杉植物中首次发现。  相似文献   
497.
Role of myeloperoxidase in the respiratory burst of human neutrophils   总被引:18,自引:1,他引:17  
Nauseef  WM; Metcalf  JA; Root  RK 《Blood》1983,61(3):483-492
Myeloperoxidase (MPO), a heme enzyme present in the primary granules of polymorphonuclear leukocytes (PMNs), has been demonstrated to participate in the oxygen-dependent microbicidal activity of these cells. Evidence for the importance of MPO in this role comes in part from studies of normal PMNs treated with the heme enzyme inhibitor, sodium azide. MPO has also been suggested to regulate the respiratory activity of PMNs during phagocytosis. The role of MPO in PMN oxygen metabolism was examined by studying parameters of the respiratory burst of PMNs from a number of unrelated MPO-deficient subjects; in addition, the ability of heme enzyme inhibitors to duplicate the MPO-deficient state was studied by treating normal and MPO-deficient cells with these compounds. MPO-deficient PMNs were found to have a time-dependent hypermetabolic response as assessed by measurement of oxygen consumption, superoxide generation, hydrogen peroxide release, and hexose monophosphate shunt activity. Catabolic pathways for hydrogen peroxide were normal, suggesting the increased recovery of oxygen metabolites reflects increased production rather than decreased catabolism of H2O2. These observations support the concept that MPO may play an important role in terminating the respiratory burst of normal PMNs. The three heme enzyme inhibitors studied--sodium azide, potassium cyanide, and 3-aminotriazole--differed greatly in the degree to which they inhibited various enzymatic systems in the PMN. Nonetheless, as a group, they exerted qualitatively similar effects on oxygen metabolism of normal and of MPO-deficient PMNs. This indicates that many of the mechanisms by which heme enzyme inhibitors influence PMN metabolism are independent of the inhibition of MPO. Conclusions from studies using such treatment of PMNs should be interpreted with caution.  相似文献   
498.
The purpose of this study was to compare the articulatory responses of children with articulatory disorders under two stimulus conditions: (1) the traditional two-picture elicitation procedure for compound words (McDonald, 1964) and (2) a single-picture elicitation procedure modeled after Clark (1985). This investigation has provided evidence that an additional factor for consideration when assessing contextual influences is the type of elicitation stimuli. The findings parallel the discrepancies between articulation performance in response to a single-word stimuli and connected speech samples.  相似文献   
499.
Shehata  WM; Meyer  RL; Costandi  YT 《Radiology》1983,146(2):523-526
A total of 119 patients with bladder cancer were irradiated over a period of 11 years. Fifteen had Stage B1, 15 B2, 38 C, 9 D1, 23 D2, and 19 D3. The pelvis, bladder, or both received less than or equal to 7,000 rad (70 Gy) in 7 weeks in 78 patients treated with curative intent (Group I) and less than or equal to 5,000 rad (50 Gy) in 5 weeks in 41 patients treated for palliation (Group II). Major complications developed in 3 patients due to irradiation and were fatal in 2, while 22 had minor, self-limited complications which were often related to the technique used. In Group I, the 3- and 5-year disease-free survival rates were 18% and 14%, respectively, whereas only 3% of Group II patients survived 3 years; however, reasonable palliation was achieved in a large percentage of cases. Superficial lesions (B1) can be cured with irradiation (60% 5-year survival). Other prognostic factors are presented.  相似文献   
500.
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