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11.
A single-chain antibody fragment (scFv) was constructed from a hybridoma antibody that binds to phosphorylcholine (PC) only when this hapten is presented in the form of the immunizing antigen (derived from Trichinella) but not when it is presented on other carriers (as found, for example, in pneumococcal capsules). The scFv derivative was found to lack this carrier specificity as it bound indiscriminately, but specifically, to the various PC-associated antigens, and exhibits a two-fold lower affinity (3.5x10(5)M(-1)) for nitrophenyl-PC than the native antibody. The findings suggest that the scFv combining site is different in fine structure from that of the native antibody. 相似文献
12.
13.
T Osanai A Konta D Chui T Kanazawa K Onodera T Kogawa 《Archives of pathology & laboratory medicine》1990,114(8):829-831
The ultrastructural characteristics of a benign adrenal adenoma that produces deoxycorticosterone and 11-deoxycortisol were examined by transmission electron microscopy. Both large, round mitochondria with a few cristae in the peripheral portion and spherical or oval mitochondria with sacrotubular cristae were observed in adenoma cells. The development of agranular or granular endoplasmic reticulum varied from cell to cell. In some cells, many vacuoles and collagenous fibers were also seen. Thus, the adrenal tumor we examined was composed of the cells derived from the fascicular zone, which are associated with Cushing's syndrome, and the cells of the glomerular zone observed in association with primary aldosteronism. 相似文献
14.
Richard D. W. Hain David Chitayat Robert Cooper Elizabeth Bandler Barry Eng David H. K. Chui John S. Waye Melvin H. Freedman 《Human mutation》1994,3(3):239-242
We describe a normal neonate who presented at four days of age with asymptomatic cyanosis. There was no evidence of cardiac or pulmonary abnormality and an extended family history included 13 other affected family members with asymptomatic cyanosis lasting one to three months. Polymerase chain reaction (PCR) amplification and direct nucleotide sequencing of the proband's Gγ chain gene revealed the mutation at codon 92 (CAC→TAC) previously shown in haemoglobin FM-Fort Ripley (α2γ2Gγ 92 (F8) His→Tyr). This is the first family with Hb FM-Fort Ripley reported so far. It demonstrates autosomal dominant inheritance of this condition and incomplete penetrance. © 1994 Wiley-Liss, Inc. 相似文献
15.
Should we screen for globin gene mutations in blood samples with mean corpuscular volume (MCV) greater than 80 fL in areas with a high prevalence of thalassaemia? 总被引:2,自引:0,他引:2 下载免费PDF全文
Chan LC Ma SK Chan AY Ha SY Waye JS Lau YL Chui DH 《Journal of clinical pathology》2001,54(4):317-320
AIMS: To investigate whether it is worthwhile, in areas where thalassaemia is common, to screen for globin gene mutations in subjects with a mean corpuscular volume (MCV) above 80 fL, especially in partners of known thalassaemia carriers. METHODS: Blood samples from 95 subjects with MCV between 80 and 85 fL were screened for the presence of alpha globin gene mutations and the haemoglobin (Hb) E mutation. RESULTS: Thirty four subjects harboured globin gene mutations. Of these, 31 had deletions of one alpha globin gene, one had Hb Constant Spring, and three had Hb E mutations. CONCLUSION: Based on the above figures and known prevalence rates of thalassaemia carriers, it would seem worthwhile to screen for globin gene mutations in partners of known thalassaemia carriers, regardless of MCV, to identify pregnancies at risk of Hb H disease or Hb E/beta thalassaemia. 相似文献
16.
Comparison of haemoglobin H inclusion bodies with embryonic zeta globin in screening for alpha thalassaemia. 总被引:1,自引:1,他引:1 下载免费PDF全文
AIMS--To compare the haemoglobin (Hb) H inclusion test with immunocytochemical detection of embryonic zeta chains in screening for alpha thalassaemia. METHODS--Blood samples from 115 patients with relevant clinical history and hypochromic microcytic indexes were screened using the HbH inclusion test and the Variant Hemoglobin Testing System (BioRad, Hercules, CA, USA). RESULTS--The HbH inclusion test was positive in 61 of 115 cases, three of whom had HbH disease confirmed by electrophoresis. The remaining 58 had alpha thalassaemia 1. All three HbH cases and 56 of 58 cases of alpha thalassaemia 1 expressed embryonic zeta chains, giving a specificity of 96.7%. Fifty four of 115 cases had a negative HbH inclusion test, of whom 50 had beta thalassaemia trait and three had iron deficiency. No diagnosis was reached for the remaining patient. CONCLUSION--The immunocytochemical test is as sensitive as the HbH inclusion test in screening for alpha thalassaemia. The presence of zeta chains is highly specific for alpha thalassaemia 1 incorporating the (--/SEA) deletion. The specificity and simplicity of the immunocytochemical test make it the test of choice in screening for alpha thalassaemia. 相似文献
17.
脑星形细胞瘤中神经细胞黏附分子与PCNA的表达及其关系 总被引:3,自引:0,他引:3
目的 :研究人脑星形细胞瘤中神经细胞黏附分子 (neuralcelladhesionmolecule ,NCAM)的表达情况及其与肿瘤增殖活性 (PCNA)的相关性。方法 :收集人脑星形细胞瘤标本 48例 ,行SP法染色。结果 :正常脑组织NCAM全部表达 ,星形细胞瘤中I~II级、III级、IV级组阳性表达率分别为 95 % (1 9/ 2 0 ) ,3 8 9% (7/ 1 8)和 2 0 % (2 / 1 0 ) ,阳性细胞表达程度随肿瘤恶性程度的增高反而降低。其表达程度与PCNA免疫反应分数 (IRS)呈负相关 (r =- 0 .6 5 7,P <0 .0 5 )。结论 :随人脑星形细胞瘤恶性程度的增高 ,NCAM表达下调 ,提示NCAM表达减少参与肿瘤的生物恶性发展。 相似文献
18.
目的 探究云南重楼Paris polyphylla var.yunnanensis(滇重楼)根茎中甾体皂苷活性成分和生物量积累随生长年限的变化状况,以期为滇重楼的质量控制提供科学依据。方法 以7、8、9、11、12、13、14、15年生滇重楼为研究对象,采用HPLC法和直接称重法测定不同年限滇重楼根茎中8种甾体皂苷(重楼皂苷Ⅰ、Ⅱ、Ⅵ、Ⅶ、Ⅲ、H、V和纤细薯蓣皂苷)含量和生物量。结果 8种甾体皂苷活性成分线性关系良好(R2≥0.999 5),精密度、重复性、稳定性和加样回收率的RSD值均小于3%,验证了该方法的可行性;随着年限的增长,滇重楼根茎生物量呈逐渐增长的趋势,其生长发育可分为增长缓慢期(第1~4年)、增长快速期(第5~10年)和增长平缓期(第11年后)3个阶段,其中7年生滇重楼根茎生物量增长最快,平均年增长量达(31.843±14.225)g;滇重楼根茎中8种甾体皂苷成分含量在不同生长年限的变化呈随机波动、无规律,《中国药典》2020版规定的3个指标成分重楼皂苷Ⅰ、Ⅱ、Ⅶ含量之和与8种甾体皂苷总和的变化趋势一致;用4个主成分对不同年限滇重楼药材进行综合评价,结果显示7年生样品在所有样品中的综合得分位于前7名。结论 建立了同时测定滇重楼中8种甾体皂苷活性成分含量的方法,可用于滇重楼的质量评价;滇重楼并非种植年限越长越好,建议以7年生滇重楼采收入药为最佳。 相似文献
19.
转化生长因子—β1及其受体的表达与大鼠肝纤维化关系 … 总被引:5,自引:0,他引:5
探讨肝纤维化形成过程转化生长因子-β及其受体的表达对胶原合成的影响。方法:采用免疫组化和斑点杂交技术,观察实验性大鼠肝纤维化过程肝内TGF-β1,TGF-βRⅡ和Ⅰ、Ⅲ型前胶原mRNA及其蛋白表达的动态变化。结果随着肝纤维化程度的加重,肝内TGF-β1、TGF-βRⅡ和Ⅰ、Ⅲ型前胶原mRNA及其蛋白表达均明显增加,组间比较均有显著差异(P〈0.05或P〈0.01)。TGF-β1与Ⅰ、Ⅲ型前胶原mR 相似文献
20.
目的 :探讨小柴胡汤分解剂在体外及体内抗柯萨奇 B3病毒 (CVB3)及保护心肌细胞的作用。方法 :用小柴胡汤分解剂通过体外微量细胞培养 ,作用于被 CVB3直接损伤的细胞模型及经腹腔感染 CVB3m Balb/ c小鼠心肌炎模型 ,分析不同浓度分解剂的效应。结果 :在体外细胞上分解剂 A、B液自 1∶ 32稀释度对 vero细胞的毒性作用已丧失 ,至 1∶ 2 5 6稀释度时 ,仍能对抗 CVB3对细胞致病变作用。在体内分解剂 A、B液治疗组小鼠 35只 ,心肌炎发生率 37.14% ;而 2 0只对照组小鼠心肌炎发生率 5 9.1% ,两者有显著性差异 (χ2 =4.6 8,P <0 .0 5 ) ,在预防给药组更为明显 (P <0 .0 1)。结论 :小柴胡汤分解剂 A、B液在体内、体外均具有抗病毒及保护心肌的作用。 相似文献