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71.
72.
常咯啉在实验性心律失常狗的药代动力学-药效动力学分析 总被引:1,自引:0,他引:1
用Harris冠脉结扎法诱发的心律失常狗研究常咯啉药代动力学-药效动力学。7只狗按83.33μg·kg ̄(-1)·min ̄(-1)静脉滴注60min,在给药期间和停药后不同时间记录ECG及测定血药浓度。C-T数据用药代程序计算药代参数;药效数据用药代-药效同步分析模型计算药效动力学参数,K10,T1/2,Vd,Cl分别为0.0087min ̄(-1),78.03min,40.55ml·kg ̄(-1)和0.421ml·kg ̄(-1)·min ̄(-1);Ke0和Ce(50)分别为0.0048min ̄(-1)和2.01μg·ml ̄(-1). 相似文献
73.
BMP2,3,4,5 mRNA在三叉神经中的表达分析 总被引:1,自引:0,他引:1
目的:明确 B M Ps 与外周神经的关系。方法:用原位杂交方法观察 B M P2,3,4,5 的m R N A在三叉神经中的表达。结果:在外周神经(三叉神经)中均有 B M P2,3,4,5 m R N A 分布, B M P2,3,4,5 的分布主要位于构成神经纤维髓鞘的雪旺细胞中;此外发现 B M P2 在部分神经纤维中也有表达。结论:首次确定了 B M P2,3,4,5 在外周神经中的表达和分布,揭示了 B M P2,3,4,5可能在外周神经的发育和再生以及形态结构的维持中发挥着调控作用。 相似文献
74.
An immunohistochemical study of keratin expression in ameloblastoma from a Kenyan population 总被引:4,自引:0,他引:4
OBJECTIVES: Ameloblastomas appear to exhibit biological heterogeneity and, except in the case of malignancy, histological appearances that do not always allow their behaviour to be predicted. The aim of this study was to assess keratin expression in African ameloblastomas and to correlate this with their clinical and histological features. MATERIALS AND METHODS: Expression of simple keratins 7, 8, 18 and 19; cornification keratins 1 and 10; basal and differentiation keratins 5 and 14 and hyperproliferation-related keratins 6 and 16 in 14-39 cases of ameloblastoma was assessed by immunohistochemical methods. RESULTS: There was patchy expression of keratin 7 in the suprabasal and stellate reticulum-like cells in some cases. All cases showed similar weak expression for keratins 8 and 18 in suprabasal and stellate reticulum-like cells but none showed keratin 1 or 10 expression. There was intense expression of keratins 5, 14 and 19 by all tumour cells suggesting that they may retain basal cell characteristics with a potential for proliferation. No consistent relationship was seen between histological types and keratin expression pattern. However, keratins 6 and 16, expressed by suprabasal and stellate reticulum-like cells, showed a marked variation within and between cases, with the highest levels of expression in squamous strands. CONCLUSIONS: We propose that squamous strands may represent the sites of most active growth within individual tumours and expression of keratins 6, 16 and 19 may be predictors of rapid growth. There is a need for further investigation of this in longitudinal clinical studies. 相似文献
75.
The advantages of the new, safer, but more expensive iodinated contrast agents are discussed, and opinions on which patient groups should receive the agents are presented. 相似文献
76.
Computed tomography (CT) was used to study 25 patients with congenital conductive hearing loss and normal external auditory canals. Deformities were subdivided according to ossicular, fenestral, and cholesteatomatous origin. Isolated ossicular deformities were found in 14 patients (five bilateral), cholesteatoma in eight, oval-window nondevelopment (with ossicular deformity) in one, and normal studies in two (congenital stapes fixation at the level of the annular ligament). Ossicular deformities may be subdivided into incudostapedial disconnections into incudostapedial disconnections (most common), malleoincudal fixations, and stapes fixations. Most are due to developmental anomaly of the first or second branchial arch. The stapes has a dual origin (second arch and otic capsule). A cholesteatoma is defined as congenital only if there is no history of otitis and the tympanic membrane is intact. In this series, six were in the middle ear proper, and two were within the attic beyond otoscopic view. Their CT appearance, with one exception, was essentially identical to that of acquired lesions. 相似文献
77.
Differential expression of CD11b/CD18 (Mo1) and myeloperoxidase genes during myeloid differentiation 总被引:6,自引:0,他引:6
During the course of differentiation of early human myeloid cells toward monocytes and granulocytes, cell surface expression of the cell adhesion molecule, CD11b/CD18 (Mo1) increases dramatically and expression of myeloperoxidase (MPO), a bacteriocidal enzyme, decreases markedly. Using the inducible promyelocytic cell line HL-60 as a model, we studied the mRNA expression of these genes. Differentiation of these cells along both a monocytic and a granulocytic pathway demonstrated that the mRNA levels of the two subunits of CD11b/CD18 increased in a pattern temporally and quantitatively similar to the increase in cell surface expression of this heterodimer. In contrast, the expression of MPO mRNA decreased in a temporal and quantitative pattern similar to the known decrease in MPO protein during differentiation, suggesting that regulation of these myeloid-specific proteins may occur at the level of mRNA expression. These findings have important implications with regard to the nature of the block in differentiation in acute nonlymphocytic leukemia and the regulation of myeloid gene expression. 相似文献
78.
79.
AIM:The present study was undertaken to isolate and standardize the various active phytochemical constituents present in the fruit rinds of Punica granatum.METHODS:Fruit rinds of Punica granatum were dried and extracted with methanol in a static extractor;the percentage yield of the methanolic extract (MEPG) was found to be 26%;the methanolic extract was partitioned using n-butanol,ethyl acetate and water;the percentage yield of the fractions were found to be 17.16%,26.88% and 47.72% respectively.HPLC was c... 相似文献
80.