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51.
52.
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4dBWG,6dBWG和6dTEW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<005).4dBWG法和6dBWG法在0020-0500IU·d-1有较好的λ值(00660和01747)和r值(09000和09237);4dBWG,6dBWG和6dTEW法测得rhGH的效价为46132,39829和48023IU/amp.6dBWG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4dBWG,6dBWG和6dTEW法测GH活性,以6dBWG法较好. 相似文献
53.
A. Komiyama I. Kamo S. Furukawa S. Akazawa K. Hirayama E. Satoyoshi 《Journal of neurology》1988,235(4):207-213
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
54.
慢性低氧性肺动脉高压大鼠血清碱性成纤维细胞生长因子含量的变化 总被引:2,自引:0,他引:2
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
55.
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
56.
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
57.
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
58.
Shibahara Hiroaki; Shigeta Minoru; Inoue Miyuki; Hasegawa Akiko; Koyama Koji; Alexander Nancy J.; Isojima Sinzo 《Human reproduction (Oxford, England)》1996,11(12):2595-2599
The blocking effects of complement-dependent sperm immobilizingantibodies in the sera of infertile women and monoclonal antispermantibodies against humans and mice on fertilization were investigated.The hemizona assay (HZA) and sperm penetration assay (SPA) wereused to study the inhibitory effects of sera from 22 infertilepatients positive for sperm immobilizing antibodies. Use ofthese tests allowed us to differentiate whether the antibodyblocked spermzona pellucida tight binding and/or spermpenetration into the ooplasm. The zona pellucida penetrationassay (ZPA) was also used to study the effects of four monoclonalantibodies (mAbs) on human sperm penetration into the zona pellucida.Seven mAbs against murine spermatozoa were tested for theirinhibitory effects on in-vitro fertilization (IVF) and HZA inmice. Of 22 patient sera with sperm immobilizing antibodies,21 (95.5%) inhibited HZA attachment and penetration, whereasthis did not occur in any of 13 patient sera without these antibodies.However, 19 of 22 (86.4%) patient sera with sperm immobilizingantibodies and eight of 13 (61.5%) patient sera without theseantibodies inhibited the SPA. Two (2C6, 1G12) of four mAbs againsthuman spermatozoa showed strong inhibitory effects in all theassays (HZA, ZPA and SPA). One mAb (3B10) did not inhibit HZAbut blocked ZPA and SPA. Another mAb (H6-3C4) seemed to haveno inhibitory effects on fertilization. Two (Vx 5 and Vx 8)of seven mAbs against murine spermatozoa inhibited IVF in micebut did not block mouse HZA. These findings suggest that antispermantibodies block fertilization at specific stages. Some of themmay inhibit sperm capacitation and thus prevent all processesof fertilization that follow. Some other antibodies may notaffect capacitation and sperm binding to zona pellucida butinhibit the acrosome reaction, followed by the blocking of spermpenetration through zona pellucida and ooplasm. 相似文献
59.
Wilkinson Karen F. Rush Bob D. Sharma Satish K. Evans David B. Ruwart Mary J. Friis Janice M. Bohanon Michael J. Tomich Paul K. 《Pharmaceutical research》1993,10(4):562-566
We showed previously that a commercially available synthetic tetradecapeptide, Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu-Leu-Val-Tyr-Ser, produces authentic angiotensin I (Ang I) upon incubation with the HIV-1 protease (S. K. Sharma et al., Anal. Biochem. 198:363, 1991). Therefore, we developed an Ang-I based activity assay for HIV protease inhibitors based on the technology developed earlier (M. J. Ruwart et al., Pharm. Res. 7:407, 1990; S. K. Sharma et al., Anal. Biochem. 186:24, 1990) for tracking renin inhibitors in rat sera. Ditekiren was either extracted from sera with ethyl acetate or assayed after the interfering substances in sera were precipitated with acetonitrile. Purified recombinant HIV-1 protease was added to extracted rat serum and the enzymatic reaction was initiated in the presence of the tetradecapeptide substrate. The inhibition of Ang I production was measured by a commercially available RIA kit. The cleanup methodology also enabled a commercially available Proteinase Scintillation Proximity Assay (SPA, Amersham) to quantify ditekiren in rat serum through the addition of recombinant HIV-1 protease and cleavage of substrate from SPA beads. Results were confirmed by HPLC or by the renin assay for ditekiren, which inhibits both aspartyl proteases. These technologies should prove useful for assessing serum levels of HIV protease inhibitors in rat. 相似文献
60.