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991.
运用ABC-爱先蓝-PAS复合染色法,分别对大鼠肝,胃、肠中不同表型肥大细胞即结缔组织肥大细胞(CTMC)和粘膜肥大细胞(MMC)进行鉴别染色实验。结果表明:肝汇管区MC呈棕褐色;胃粘膜上皮及粘膜下结缔组织内MC分别被染成蓝色和棕褐色;肠粘膜固有层MC呈蓝色.通过不同颜色反应从而确定其MC表型。本实验还通过对染色顺序。固定液选择等的多次摸索。取得了较好的染色效果,与其它检测方法的结果相一致,但试剂来源方便,操作简易。一般实验室即可进行。 相似文献
992.
讨论了带随机输出噪声的线性时不变对象的参考模型自适应系统。提出一种适用于这种系统的混合自适应控制律,证明该系统所有信号的有界性,计算机仿真验证这种新的混合自适应控制律在存在随机输出噪声的系统中的性能。 相似文献
993.
将SRSV/3T3细胞DNA转染NIH/3T3细胞,转染后17d,实验组出现18个集落,对照组出现4个集落。将实验组集落细胞接种于3只BALB/C裸鼠皮下,全部长成纤维肉瘤。将SRSV/3T3细胞DNA用EcoRI和BamHI酶切电泳,分别应用5种癌基因(v-myc、KJ-ras、v-src、v-sis和e-fos)作Southern印迹和分子杂交。发现SRSV/3T3细胞DNA的BamHI酶切片段与c-fos探针杂交后,在2.2~3.0 kb处出现阳性杂交带。应用c-fos单抗检测转化细胞,细胞核内呈阳性反应。表明SRSV/3T3细胞DNA含有fos样转化基因,在转化细胞内有此基因的过度表达。 相似文献
994.
Shiro Nakaike Takehiro Yamagishi Kayoko Nanaumi Susumu Otomo Shigeru Tsukagoshi 《Cancer science》1992,83(4):402-409
A novel antitumor compound, N-β-dimethylaminoethyl 9-carboxy-5-hydroxy-10-methoxybenzo[a]-phenazine-6-carboxamide sodium salt (NC-190), was evaluated for antitumor activity in vitro against cultured tumor cell lines, and the kinetics of cell killing was elucidated. NC-190 strongly inhibited the growth of all of 3 murine tumor cell lines, 7 human tumor cell lines and 2 normal cell lines. With continuous exposure, the 50% inhibition concentrations were in the range of 0.005–0.06 μg/ml, except for KATO-III (2.15 μ g/ml). By colony-forming assay, concentrations of NC-190 giving 90% cell kill (IC90 ) at various exposure times were obtained with HeLa S3 cells. The plot of IC90 exposure time on a log-log scale was linear for NC-190 with a slope of -1, which is typical for cell cycle phase-nonspecific agents. A 2 h treatment with NC-190 induced a rapid reduction in cell viability at doses of more than 3 μ g/ml. At the dose where colony formation was completely inhibited, cell viability was persistently reduced to below 20% during the cell culture period. NC-190 cauced a dose- and time-dependent reduction in DNA synthesis. The inhibitions of RNA and protein synthesis were less than that of DNA synthesis. Spectroscopic studies of NC-190 mixed with calf thymus DNA demonstrated that NC-190 was capable of interacting with DNA. However, DNA thermal denaturation studies suggested that intercalation of NC-190 was weak in comparison with those of classical intercalating drugs. 相似文献
995.
NAOHIRO WATANABE YUKIFUMI NAWA KENICHI OKAMOTO AKIO KOBAYASHI 《Parasite immunology》1994,16(3):137-144
The roles of IgE and mast cells on expulsion of adult Hymenolepis nana from the intestine were examined in mice. IgE-dependency was determined by comparing congenitally IgE-deficient SJA/9 and IgE-producing SJL/J mice infected with 50 H. nana eggs. Anti-H. nana IgE antibody was detected at three weeks post infection (p.i.) in SJL but not in SJA mice. The number of adult worms in the intestines of SJA and of SJL mice were similar at two weeks, but significantly more were found in SJA mice at three weeks p.i. Treatment of mice with anti-ɛ antibody also resulted in an increased worm burden at three weeks, suggesting participation of IgE in expulsion of H. nana. Intestinal mastocytosis was induced by infection regardless of the IgE status of the mice. Mast cell-dependency was tested in mast cell-deficient W/Wu and in normal littermate +/+ mice infected with 100 H. nana eggs. Anti-H. nana antibody was detected in both groups of mice at three weeks p.i. Worm expulsion seemed to be mast cell dependent because expulsion was less complete in W/Wu mice at three weeks p.i. Peripheral blood eosinophilia was comparable at three weeks p.i. in both IgE and mast cell sufficient and deficient mice. These results suggest that IgE and mast cells participate in the expulsion of H. nana adults from intestine in mice. 相似文献
996.
997.
备用根大鼠脊髓后角提取液中神经营养活性组分的分离及生物活性测定 总被引:1,自引:0,他引:1
制作备用根大鼠脊髓后角提取液,取其分子量大于10kD的组分进行SDS-聚丙烯酰胺凝胶电泳分析,发现手术侧和非手术侧的电泳区带数目大致相同,但手术侧样品的第四条蛋白质区带扫描的吸收峰面积百分比大于非手术侧样品的第四条区带,两者在量上可能有差别。将手术侧样品经交联葡聚精G-75凝胶层析,得到两个洗脱峰.第一峰洗脱液有促进体外培养的背根节神经元存活及其突起生长的作用,其电泳分析显示4条主带,分子量在40~80kD之间.实验结果提示部分去传入纤维支配的脊髓后角组织含有神经营养活性物质,该物质的分子量约在40~78kD之间. 相似文献
998.
Stability of the Defibrillation Probability Curve with the Development of Ventricular Dysfunction in the Canine Rapid Paced Model 总被引:1,自引:0,他引:1
PAUL A. FRIEDMAN DAVID A. FOLEY TIMOTHY F. CHRISTIAN MARSHALL S. STANTON 《Pacing and clinical electrophysiology : PACE》1998,21(2):339-351
Most patients with implantable defibrillators have diminished cardiac function. Progressive heart failure might impair defibrillation efficacy, leading to interpreted device, failure. This study sought to determine the effect of ventricular dysfunction on defibrillation energy using a biphasic endocardial system. Eleven dogs were ventricularly paced at 225 pulses/min for 2 weeks to induce ventricular dysfunction, and five control dogs remained unpaced. Dose response defibrillation probability curves were generated for each animal at baseline, after 2 weeks (at which time the pacemakers were turned off in the paced group), and then 1 week later. The defibrillation thresholds, ED20 , ED50 , and ED80 (the 20%, 50%, and 80% effective defibrillation energies, respectively) were determined for each dog at each study. In the paced dogs, the mean ejection fraction fell from 55% to 25% after pacing (P < 0.0001), and rose to 46% after its discontinuation (P = 0.0002). The defibrillation threshold, ED20, ED50 , and ED80 remained unchanged in both the control and paced groups for all three studies, even after adjustment for dog weight or left ventricular mass. Rapid pacing produced no change in left ventricular mass. It induced ventricular cavity dilatation and wall thinning, which had opposing effects on defibrillation energy requirements, resulting in no net change of the ED50 in heart failure. In conclusion, the defibrillation efficacy of a biphasic transvenous system is not changed by the development of heart failure using the rapid paced canine model. 相似文献
999.
目的探讨低血流期间无销对再灌注心脏功能恢复的影响。方法采用等客收缩大鼠灌流心脏模型,低血流期以无钠的Krebs-Henseleit(K-H)液灌注.San-ei362型多道重理记录仪,测定再灌注不同时刻左心宝功能及乳酸脱氨酶活性.结果再灌注30min.在各相应时刻,缺钠组左心室收缩压(LVSP)、心率(HR)、左心室内压最大上升速率(dp/dtmax)的恢复均显著高于对照组(P<0.001),左心室舒张期末压(LVEDP)显著低于对照组(P<0.001),乳酸脱氢酶数据低于对照组。结论低血流缺血间无销减轻了心脏血液动力学的损害,心肌乳酸脱氢酶的漏出减少,这可能与因低血流期间无销细胞内钠超负荷减轻有关。 相似文献
1000.