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81.
A novel in vitro assay of renal epithelium tight junction function was used to assess the efficacy with which rabbit anti-thymocyte globulin (ATG) blocks epithelium damage mediated by lymphokine-activated killer (LAK) cells. It was found that LAK cells lysed renal epithelial cells poorly in standard chromium-release assays but that they caused a rapid, and almost total, reduction in trans-epithelium monolayer resistance, indicating tight junction failure and, hence, loss of tissue function. LAK cell-mediated cytolysis of the sensitive K562 cell line was completely blocked in the presence of ATG at a concentration of 200 g/ml. Addition of ATG at this concentration to damaged renal cell monolayers in the presence of LAK cells allowed the trans-monolayer resistance to recover rapidly to levels approaching the values recorded before initial addition of LAK cells. On this basis it seems likely that the rapid restoration of renal function frequently observed after appropriate rescue therapy during episodes of acute rejection may reflect subtle changes in tissue function rather than recovery from widespread graft cell cytolysis.  相似文献   
82.
Praziquantel, a new anthelmintic drug with activity against all species of schistosomes pathogenic to man, and against a wide range of Cestodes, was tested for mutagenic potential. For the detection of both base substitutions and frameshift mutations, Salmonella typhimurium TA 100 and TA 98 were used as tester strains. Using the plate assay with and without added S-9, host-mediated assay and urine-mediated assay without and after incubation with -glucuronidase/arylsulfatase, no mutagenic activity could be detected.  相似文献   
83.
84.
This study determines the relative ocular lens irritancy of 16 common partially transparent or non-transparent consumer hygiene products. The irritancy was found by measuring the changes in the sharpness of focus [referred to as the back vertex distance (BVD) variability] of the cultured bovine lens using a scanning laser In Vitro Assay System. This method consists of a laser beam that scans across the lens, and a computer, which then analyses the average focal length (mm), the BVD variability (mm), and the intensity of the beam transmitted. Lenses were exposed to the 16 hygiene products and the lens’ focusing ability was monitored over 192 h. The products are semi-solids or solids (e.g. gels, lotions, shampoos). They are categorized into six groups: shampoos, body washes, lotions, toothpastes, deodorant, and anti-perspirant. Damage (measured by > 1 mm BVD variability) occurred slower for the shampoos, especially in the case of baby shampoo. The results indicate that shampoos exhibit the lowest level of ocular lens toxicity (irritability) while the deodorant is the most damaging.  相似文献   
85.
MTT法药敏试验应用于晚期乳腺癌   总被引:7,自引:0,他引:7  
[目的]探讨MTT法体外药敏试验在复发转移性乳腺癌化疗中的价值。[方法]取40例复发转移性乳腺癌患者肿瘤组织,以简易机械法制备细胞悬液,应用MTT法体外药敏试验测定其对10种常用化疗药物的敏感性,并指导临床用药,同时与临床疗效进行相关分析。[结果]MTT法检测复发转移乳腺癌患者药敏试验的成功率为92.5%,敏感性为87.5%,特异性为69.2%。阳性预测值为84.0%,阴法预测值为75%,总的预测准确率为81.1%。[结论]MTT简便快速,可作为临床上指导复发转移乳腺癌个体化化疗的有效方法.  相似文献   
86.
抗体夹心酶联免疫吸附法测定重组E.coli L-门冬酰胺酶研究   总被引:1,自引:0,他引:1  
用重组E.coliL-门冬酰胺酶免疫家兔,DEAE-纤维素柱层析纯化IgG,采用二步戊二醛交联法将辣根过氧化物酶标记抗体,建立抗体夹心酶联免疫吸附法,测定大鼠血浆中重组E.coliL-门冬酰胺酶浓度。本测定方法的线性范围为1~64U/L,灵敏度为0.4U/L。建立的抗体夹心酶联免疫吸附法测定大鼠血浆中重组E.coliL-门冬酰胺酶具有良好的精密度、回收率、灵敏度和特异性。  相似文献   
87.
高效液相色谱法测定维生素E烟酸酯胶囊的含量   总被引:1,自引:0,他引:1  
目的:采用高效液相色谱法测定维生素E烟酸酯胶囊的含量。方法:以Phenomenex Luna C18(250 mm×4.6 mm,5 μm)柱为分析柱,甲醇-0.01%三氟醋酸乙腈(80:20)为流动相,流速1.5 mL·min~1,检测波长264 nm。结果:维生素E烟酸酯在84-839 μg·mL-1范围内峰面积与浓度线性关系良好(r=1.000);平均回收率为100.4%,RSD<1%。结论:本方法准确、简便、快速,适用于测定维生素E烟酸酯胶囊的含量。  相似文献   
88.
那法瑞林长效制剂对大鼠垂体功能影响   总被引:1,自引:0,他引:1       下载免费PDF全文
 目的:观察国产那法瑞林(nafarelin )长效制剂的长效作用及对大鼠垂体功能影响,并探讨其作用部位。方法:采用大鼠间质细胞睾酮 (RICT)法检测血清LH(luteinizing hormone)生物活性水平。结果:那法瑞林长效制剂在体内的持续释药时间为((40.0±6.8)d。单次理植3周后大鼠血LH的周期性分泌高峰及激发高峰均消失。预先理植长效制剂组大鼠血LH在切除双侧卵巢后变化不明显。结论:那法瑞林长效制剂确有长效作用,其通过作用于垂体而抑制大鼠垂体功能。  相似文献   
89.
目的:测定清热解毒口服液中黄芩苷的含量。方法:采用HPLC法,用C18柱,甲醇-水-磷酸(50:50:0.3)为流动相,检测波长276nm。结果:在4.775~191μg/ml的浓度范围具有良好的线形关系。R=1.000(n=6),平均回收率105.6%,日内精密度为1.63%(n=5)。结论:此方法快速、专属,准确。  相似文献   
90.
Epitopes of human brain acetylcholinesterase   总被引:4,自引:0,他引:4  
Zhang XM  Liu G  Sun MJ 《Brain research》2000,868(1):157-164
The main purpose of the present work was to identify B-cell epitopes on human brain acetylcholinesterase (AChE) by the synthetic peptide approach. Five hundred and seventy-four decapeptides comprising amino acids No. n to n+9 (where n denotes the residue number of the 583 amino acids in the primary structure of human brain AChE and is an integer in the range 1-574) were synthesized, using the multipin combinatorial chemical synthesis technique, and biotinylated. Epitopes of human brain AChE were detected by enzyme-linked immunosorbent assay (ELISA) and compared with the predicted epitopes of human AChE by 'Goldkey' software. Among 574 synthetic decapeptides, 47 decapeptides at 11 antigenic regions showed immunoreactivity with mouse anti-human brain AChE polyclonal antibodies. The minimum sequence of epitope was defined at every antigenic region explored. The locations and sequences of the former ten continuous epitopes at the 11 antigenic regions of the human brain AChE had been identified as follows: TPVLVWIY (112-119), RTVLVSMNY (143-151), LLDQRLALQW (173-182), RRATQLAH (246-253), VFRFSFVPV (294 approximately 302), KDEGSYFLVY (332-341), RVYA (424-427), LMRY (476-479), KAPQWPPY (496-503), GLRAQACAFW (523-532). The rate of hits of the predicted epitopes from the software came out at 33%. In our work, the epitopes of human AChE have been mapped by purified polyclonal antibody at eleven distinct sites in the primary structure.  相似文献   
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