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21.
P J Harrison A W Procter A J Barton S L Lowe A Najlerahim P H Bertolucci D M Bowen R C Pearson 《Brain research. Molecular brain research》1991,9(1-2):161-164
In situ hybridization histochemistry has been used to study the amount of M1 muscarinic receptor mRNA in temporal cortex from subjects with Alzheimer's disease and other neurodegenerative disorders, where the duration of terminal coma was known. Total polyadenylated mRNA and glutamate decarboxylase activity were also measured. Both muscarinic receptor mRNA and enzyme activity showed a significant decline with increasing duration of terminal coma, but were not related to diagnosis. Polyadenylated mRNA signal did not show an association with coma. These data indicate the need to consider the nature of the terminal illness in post mortem studies of mRNA as well as for neurochemical research. 相似文献
22.
The purpose of the present paper is to identify the processesof changing dietary fat consumption using Prochaska's transtheoreticalmodel. This model assigns individuals into a series of stages,emphasizing the cognitive, social and behavioral steps of change.At each of the stages an individual focuses on different processes,or coping strategies, to enable movement to the next stage.Dietary process items were created by a multidisciplinary teamusing the smoking processes as a model. These items were subjectedto a Q-sort and piloted in convenience samples. The processitems were distributed with staging questionnaires to 720 membersof an outdoor folk music festival audience. The final groupof 121 process items was subjected to exploratory factor analysisof principle components with varimax rotation. Eight independentfactors emerged during this factor analysis. The processes measuredby the final 60-item questionnaire relate to the stages of changein the hypothesized manner. Applications of this model to interventionsettings seem possible. 相似文献
23.
The serum erythropoietin (EPO) concentration in patients with myelodysplasia (MDS) varies widely at similar hemoglobin concentrations, although the reasons for this variation are unclear. We have studied the pharmacokinetics of an i.v. bolus of recombinant human EPO in ten subjects with myelodysplasia. Basal serum EPO concentration varied from 210 to 5984 mU/ml. Plasma half-time clearance (t1/2) varied from 3.9 to 20.0 h. A significant positive correlation was found between t1/2 and basal EPO concentration. An increase in immature peripheral blood reticulocytes was found on days 1 and 2 after EPO treatment; this may represent either an effect on hemopoiesis or on reticulocyte release from the bone marrow. 相似文献
24.
We report here the development of anti-Fy5 in a young Negro female with sickle cell disease. The antibody was responsible for a delayed hemolytic transfusion reaction. We believe this is the first report of such an antibody in Europe. 相似文献
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胰岛素样生长因子Ⅰ型受体单克隆抗体对结肠癌细胞生长的影响 总被引:2,自引:0,他引:2
目的探讨胰岛素样生长因子Ⅰ型受体(insulin-like growth factorⅠ receptor,IGF-ⅠR)在人结肠癌细胞株HT-29上的表达,以及两种胰岛素样生长因子Ⅰ型受体单克隆抗体(IGF-ⅠRMcAb)对HT-29细胞增殖的影响.方法免疫组织化学法检测HT-29的IGF-ⅠR表达,MTT法检测两种IGF-ⅠR McAb对HT-29的抑制增殖作用及诱导凋亡情况.结果人结肠癌细胞株HT-29细胞膜高表达IGF-ⅠR.IGF-ⅠR McAb能抑制HT-29细胞增殖,McAb对HT-29细胞的抑制作用随抗体浓度增大而增大.IGF-ⅠR McAb诱导HT-29凋亡,与对照组相比差异有统计学意义(P<0.01).结论IGF-ⅠR McAb通过阻断IGF-ⅠR抑制结肠癌细胞增殖、诱导细胞凋亡. 相似文献
28.
目的检测颅咽管瘤组织中DNA拓扑异构酶Ⅱα(DNATopoⅡα)的表达情况,分析其表达与肿瘤复发的关系,探讨其是否可作为判定颅咽管瘤预后的一个有效指标。方法设计前瞻性队列研究方案,采用免疫组化方法和图像分析技术测定63例颅咽管瘤组织切片中DNA拓扑异构酶Ⅱα的表达水平,评价颅咽管瘤釉质上皮瘤与鳞状乳头瘤病理亚型、复发组与非复发组、原发组与复发组之间肿瘤细胞的增殖能力。结果32例釉质上皮瘤14例复发,31例鳞状乳头瘤6例复发;釉质上皮瘤与鳞状乳头瘤病理亚型之间以及复发组与非复发组肿瘤之间DNA拓扑异构酶Ⅱα的表达水平有显著性差异(P<0.05),而原发组与复发组肿瘤之间DNA拓扑异构酶Ⅱα的表达水平无统计学差异(P>0.05)。结论颅咽管瘤的病理亚型以及DNA拓扑异构酶Ⅱα的表达水平与肿瘤的预后和复发有关,可作为预测肿瘤复发危险性的一个参考指标;DNA拓扑异构酶Ⅱα的表达水平在原发组和复发组肿瘤之间无显著性差异,提示肿瘤在复发过程中瘤细胞的增殖活性无明显变化。 相似文献
29.
Experimental microvascular growth plate transfers. Part 2--Investigation of feasibility 总被引:1,自引:0,他引:1
C V Bowen B M O'Brien G J Gumley 《The Journal of bone and joint surgery. British volume》1988,70(2):311-314
We investigated the feasibility in the dog of using transfers of the distal ulna into the radius either as growth plate replacements or as accessory growth plates in the diaphysis. Preliminary work determined the most satisfactory method of skeletal fixation. The experimental study showed that transfers used as growth plate replacements grew at almost normal rates, uniting with the recipient bone in a mean of 7.1 weeks. Transfers into the diaphysis initially nearly doubled the growth rate of the radius, although in the long-term results were unsatisfactory, because of fracture of the graft after a mean period of 8.2 weeks. 相似文献
30.
By synthesizing and testing a part-structure, N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (3), derived from our previously reported high affinity sigma receptor ligands (1S,2R)-(-)-N-[2-(3,4-dichlorophenyl)-ethyl]-N-methyl-2-(1- pyrrolidinyl)cyclohexylamine [(-)-2] and (+)-2, we have identified a novel class of superpotent (subnanomolar affinity) sigma ligands specific for the sigma receptor labeled by [3H]-(+)-3-PPP. When 3 was tested for its capacity to displace [3H]-(+)-3-PPP from guinea pig brain membranes, it exhibited a Ki of 0.34 nM, which is better than either of its parent compounds (-)-2 (Ki = 1.3 nM) and (+)-2 (Ki = 6.0 nM). Other compounds related to 3 such as N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-homopiperidinyl)ethy lamine (19) exhibited Ki = 0.17 nM [( 3H]-(+)-3-PPP). The determinants for high sigma receptor affinity of 3 were examined by manipulation of this structure in a number of different ways. The high efficacy of these compounds for the sigma receptor, their relative chemical simplicity and ease of synthesis, and their high degree of selective identifies N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)ethylamine (3) and related compounds as a highly promising base for determination of the functional role of sigma receptors as well as the development of novel therapeutic agents. 相似文献