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111.
目的:建立测定生长激素(GH)在体生物活性的方法.方法:以去垂体大鼠体重增长(BWG)和胫骨骺软骨板宽度(TEW)为指标,观察动物性别、给药途径、次数和周期不同对效应的影响;同时进行4dBWG,6dBWG和6dTEW法,测定GH的效价(平行线3×3设计).结果:♀和♂sc和im给药以及每日给药1次和2次的BWG和TEW差异无显著意义.给药6d比给药4d引起较大的BWG和TEW(P<005).4dBWG法和6dBWG法在0020-0500IU·d-1有较好的λ值(00660和01747)和r值(09000和09237);4dBWG,6dBWG和6dTEW法测得rhGH的效价为46132,39829和48023IU/amp.6dBWG法有较小的λ值和较低的ARFL值.结论:可在同一组去垂体大鼠体内同时用4dBWG,6dBWG和6dTEW法测GH活性,以6dBWG法较好.  相似文献   
112.
Tacrolimus metabolite cross-reactivity in different tacrolimus assays   总被引:4,自引:0,他引:4  
Objectives: Tacrolimus (FK506) is an immunosuppressive drug with great clinical promise. There is a controversy regarding the role of tacrolimus metabolites in immunosuppression and toxicity, and immunoassays and immunophilin binding assays have not been adequately tested for metabolite cross-reactivity. Methods are limited to HPLC and HPLC-MS for quantifying the parent drug. Mixed lymphocyte culture assay (MLC) is the preferred functional bioassay for the measurement of parent drug and active metabolites but it is not practical for routine laboratory use. Due to differences in assay methods and reagent specificity, the concentration of tacrolimus in a given specimen may vary among different assay kit manufacturers. The objective of this study was to evaluate the degree of cross-reactivity or interference of the three first-generation tacrolimus metabolites [13-O-demethyl (M-I), 31-O-demethyl (M-II) and 15-O-demethyl (M-III)] among two different tacrolimus immunoassays (Immunoassay: PRO-Trac II FK506, Abbott IMx tacrolimus-II); and the radioreceptor assays (RRA) using minor immunophilins (14, 37, and 52 kDa immunophilins) and tacrolimus binding protein (FKBP12).

Methods: First-generation tacrolimus metabolites (M-I, M-II, and M-III) spiked in drug-free whole blood were assayed with RRA using three minor immunophilins (14, 37, and 52 kDa) and two commercial immunoassay procedures (Incstar PRO-Trac II tacrolimus, Abbott IMx tacrolimus II). The results were compared to previously published FKBP-12 RRA data and their immunosuppressive potency.

Results and conclusion: The first generation tacrolimus metabolites (M-I, M-II, and M-III) were tested using concentrations of 10 and 20 ng/mL. The significance of the metabolite interference (% of the total interference) was calculated based on the relative concentration of each metabolite present at steady-state trough concentrations in renal transplant recipients [22]. Metabolite I, which has no functional immunosuppressive activity showed minimal interference compared to M-II and M-III in all assays except the 14 kDa RRA. The Incstar PRO-Trac II tacrolimus assay showed the least M-I interference. Metabolite-II, which has a pharmacologic potency similar to the parent drug, showed a significant interference in the immunoassays and significant interference in radioreceptor assays. Metabolite III, which is pharmacologically inactive, produces 3–10% interference in the different assays if its presence in the blood is 6% of the parent drug. The total interference from these three metabolites was greater in the immunoassays than in the receptor assays. Receptor assays for tacrolimus provide results closer to the target value than do immunoassays.  相似文献   

113.
HPLC—ELSD法测定磷脂的纯度和含量   总被引:1,自引:0,他引:1  
《药物分析杂志》2006,26(12):1826-1828
  相似文献   
114.
Summary Antibodies against phosphate-buffered-saline extracts (SE) of non-acetylcholine receptor (AChR) skeletal muscle antigens were found in patients with myasthenia gravis (MG). The antigenicity of SE was distributed in three fractions with molecular masses of over 200 kDa, 90–150 kDa and 7–14 kDa on gel filtration. These fractions shared common antigenicities. Further analysis of 90–150 kDa fractions on sodium dodecyl sulphate polyacrylamide gel electrophoresis showed five major bands, ranging from 105 kDa to 275 kDa. The antibodies against SE were detected in 52% (58/112) of the MG patients; incidence and titres were higher in the thymoma group (n=21; 90% and 0.872 respectively) than in the non-thymoma group (n=91; 43% and 0.200, P<0.001). In patients without a thymoma, these antibodies were frequently observed in late-onset disease and the severe generalized form (P<0.01). In 4 of 7 ocular MG patients without anti-AChR antibodies, low but appreciable levels of anti-SE antibodies were found. In 73% (11/15) of generalized MG patients treated with prednisolone and thymectomy, anti-SE antibody titres changed in association with those of anti-AChR antibodies and with the clinical course. Both antibody titres increased synchronously in patients who developed crises.  相似文献   
115.
为探讨碱性成纤维细胞生长因子(bFGF)在慢性低氧性肺动脉高压肺血管重建中的作用及机理,采用慢性低氧性肺动脉高压大鼠模型,用酶联免疫吸附法测定其血清bFGF含量,并用原位杂交法观察肺、心、脑、肾等器官bFGFmRNA表达的变化。结果显示:低氧组血清bFGF含量(35.9±23.5pg.ml-1)明显高于对照组(6.30±0.97pg.ml-1,P<0.005);低氧组肺小动脉bFGFmRNA表达明显增强,而心、脑、肾bFGFmRNA表达无变化。提示bFGF参与了慢性低氧性肺动脉高压肺小动脉重建的调控。  相似文献   
116.
正常人双眼旋转融合功能的研究   总被引:1,自引:0,他引:1  
目的 :探讨正常人双眼旋转融合功能。方法 :采用随机点同视机立体图 (random dotstereogramssynoptophone,RDSS)检测 6 2例正常人双眼旋转融合范围和旋转融合恢复力。结果 :①RDSS 80 0″~ 6 0″双眼外旋融合力是 (11.79± 3.4 0 )°~ (8.2 3± 1.91)°,内旋融合力是 (9.38± 3.4 0 )°~ (6 .4 8± 2 .72 )°。②RDSS不同视锐度的各组间比较 ,仅 2 0 0″和 6 0″内旋融合组之间差异无显著性 (P =0 .14 1) ,其余内旋、外旋融合各组间差异均有显著性 (P≤ 0 .0 1)。③RDSS 80 0″~ 6 0″双眼外旋融合力恢复点为 (5 .77± 1.89)°~ (3.6 7± 1.17)°,内旋融合力恢复点 (3.6 9± 1.2 1)°~ (2 .35± 1.4 0 )°。结论 :①双眼外旋、内旋融合力范围随立体视锐度的增高呈下降趋势 ,即视差越大 ,旋转融合力越大。②不同立体视锐度 ,其外旋、内旋融合力表现不同 ,能反映出与旋转融合功能的关系。临床可采用RDSS对双眼旋转融合力及范围进行检测。  相似文献   
117.
B细胞杂交瘤技术制备抗同种特异T细胞膜抗原单克隆抗体   总被引:1,自引:0,他引:1  
目的:为进一步分析TCV免疫诱导同种免疫反应低下的机制。方法:采用B细胞杂交瘤技术获得分泌单克隆抗体的杂交瘤细胞。结果:两次的细胞融合中共得到12株稳定分泌单抗的杂交瘤细胞,为分析抗体在TCV中的作用提供条件。结论:TCV免疫可引起抗TCV细胞抗体的产生,以同系免疫的方法得到的活化B细胞用于B细胞杂交生产单抗是可行的。  相似文献   
118.
应用与凝血酶原及异常凝血酶原有免疫交叉反应的非Ca(Ⅱ)依赖性抗人凝血酶原抗体,建立夹心BA-ELISA法,检测人血浆凝血酶原的最低浓度可达1ng/ml。血浆经皂土和柠檬酸钡吸附处理,除去纤维蛋白原和凝血酶原后,可用本法检出存留于血浆中的微量异常凝血酶原,并测得健康人血浆异常凝血酶原的均值为74.61±19.43ng/ml。本法操作简便,特异性强,重复性好。  相似文献   
119.
The random dot stereogram E (RDE) has been shown to be a simple and effective test for the detection of binocular abnormalities and defective visual acuity in children. We determined the validity of the RDE as a screening test for reduced visual acuity, amblyopia and strabismus in two separate populations of children.
A nonselective group of 100 school children (aged 5 to 15 years) who presented consecutively to the ophthalmology department at Auckland Public Hospital were tested with the RDE. All cases of amblyopia and strabismus were detected by the RDE. Similar screening with the RDE test of 168 preschool children (aged three to four years) in the community resulted in an unacceptably high over-referral rate. The test was unreliable in the preschool age group because of difficulty in distinguishing between test failure and non-cooperation with the test. The low positive predictive value of the test in the younger age group suggests the test to be unsuitable for preschool vision screening.  相似文献   
120.
非创伤性股骨头坏死患者的血液学改变   总被引:7,自引:0,他引:7  
目的测定非创伤性股骨头坏死(nontraumaticosteonecrosisoffemoralhead,NONFH)患者的血液学指标变化,筛选敏感分子标记物用于早期诊断和筛选高危人群。方法研究对象共分三组:(1)NONFH早期组(塌陷前期)30例,(2)NONFH晚期组(塌陷后期)30例,(3)正常对照组30例。各组对象均抽取空腹肘静脉血。应用酶联免疫吸附法(ELISA)测定血小板α-颗粒膜蛋白(GMP-140)、血浆蛋白C(PC)、D-二聚体(D-Dimer)含量;发色底物法测定血浆纤溶酶原激活剂抑制剂(PAI)活性。结果(1)NONFH早、晚期组血小板GMP-140含量均高于正常对照组,血浆PC含量均低于正常对照组,D-Dimer含量均高于正常对照组,PAI活性均高于正常对照组(P均<0.05)。骨坏死情况越严重,各项指标上升或降低的趋势越明显,而且各项指标早、晚期组间比较差异均有显著性(P均<0.05)。(2)经判别分析,筛选出PAI、D-Dimer、PC三个指标,建立NONFH早期、晚期和正常对照三类判别函数式。NONFH早期:Y1=?26.3966 41.4916X10 0.0512X4 4.1390X1;NONFH晚期:Y2=?66.7566 82.1315X10 0.1082X4 2.7233X1;正常对照组:Y3=?26.7049 20.5695X10 0.0327X4 6.1900X1。回代判对率97.78%。结论(1)NONFH患者各期均存在高凝和低纤溶状态。(2)PAI、D-Dimer、PC为NONFH患者的血液学敏感指标。  相似文献   
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