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991.
992.
In the present paper we report the mitogenic effect of the sheep anti-porcine lymphocyte E-receptor antiserum IgG(APERIgG) on porcine peripheral T-lymphocytes in vitro. The effect was apparently dose-dependent and not seen in the B-lymphocyte cultures. Kinetic study showed that the maximal 3H-thymidine incorporation, similar to that induced by Con A, occurred on the third day of incubation. Neither F(ab')2 nor Fab fragment of APERIgG was able to induce cell proliferation, indicating that the integrity of IgG molecule was essential for cell response. It was very interesting to note that though there is cross antigenicity between porcine and human E-receptors, no similar effect could be produced by APERIgG in human peripheral lymphocyte cultures under the same experimental conditions, suggesting the existence of minor difference in structure between the porcine and human E-receptors. 相似文献
993.
G. S. Liu P. K. Basu G. E. Trope 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1987,225(5):325-330
The purpose of this study was to determine whether timolol maleate (Timoptic) is cytotoxic to the cornea. The drug was applied as topical drops for 1 month to control rabbit eyes and rabbit eyes from which the epithelium had been removed or to de-epithelialized full-thickness autografts. Clinically all corneas and grafts remained clear. Scanning and transmission electronmicroscopy however revealed is drug induced epithelial damage, defective epithelial wound healing, and endothelial changes. The endothelial changes were most prominent in the group of rabbits that underwent de-epithelialization before corneal grafting. 相似文献
994.
目的:本项研究针对已编制完成的具有语音平衡特性的双音节普通话测听词汇表(MSTM)进行难度等价性分析,以期挑选出具有难度一致性的一组词表应用于临床。方法:对10张(每张50词)的双音节词表进行数字化录音。选取65名年龄18~25岁具有大专以上文化程度,日常生活中以普通话为交流方式的听力正常人作为受试者。对5名受试者进行预试验,获得正式测试时所需的给声强度。对60名受试者进行正式的言语识别测试,使用SPSS11.0软件对结果进行等价性分析。结果:10张双音节测试词表中,除测试表5外,其余各表间均具有难度等价性。结论:9张双音节普通话测听词汇表具有较好的难度等价性,可应用于临床测试和实验研究中。 相似文献
995.
人冠状病毒72-62和73-50干燥毒种,用人胚器官和原代人胚肾细胞合管培养未能引起细胞病变,而将病毒液接种到人胚器官细胞或人胚肺传代细胞第一代就能引起明显的细胞病变。新传代病毒经电镜及中和试验鉴定确属人冠状病毒。实验结果证明人胚肺传代细胞比原代人胚肾细胞敏感,为进一步研究人冠状病毒提供了一株敏感的细胞。 相似文献
996.
本研究测定了荔枝果实发育期间内源激素含量的动态。结果表明果实发育前期细胞分裂素(CTK),生长素(IAA)含量较高;中期乙烯(Eth),赤霉素(GA),的含量较高,这与果实的生长发育及落果有密切相关。同时,果实发育前期应用外源CTK、中期应用GA、处理果穗可显著提高产果率。 相似文献
997.
998.
作者对10例军团菌肺炎和10例非军团菌肺炎患者临床资料进行分析。本组军团菌肺炎特点为:病情重、进展快、消化道症状及肌肉关节痛、低钠血症、低氧血症、代酸或呼碱发生率较高,X线胸片多见双侧或多叶肺浸润伴胸膜反应,病死率高。 相似文献
999.
J C Pinilla B Webster M Baetz B Reeder S Hattori L Liu 《JPEN. Journal of parenteral and enteral nutrition》1992,16(5):408-412
The objective of this study was to evaluate body composition as measured by bioelectric impedance analysis using splints and body positions differing from the standard supine position. Forty-three patients, randomized into two groups of different body positions, and 101 healthy volunteers were prospectively studied. Resistance and reactance of body tissues were measured by bioelectric impedance analysis. Body composition is described by a three-compartment model composed of body fat, body cell mass, and extra cellular mass. The patients were measured in the standard supine position and then randomized into two groups. They were then remeasured with the appropriate splinting device or position change. Volunteers were measured in the standard supine position and all four alternative positions. There was a statistically significant difference demonstrated in whole body resistance, whole body reactance, body cell mass, and the ratio of extracellular mass to body cell mass in some body positions. The percentage of change with different body positions and splints, when compared with the standard supine position, was generally below 2%, a clinically insignificant difference. We conclude that the reliability of resistance and reactance as measured by bioelectric impedance analysis is clinically valid using any of the tested body positions and/or splints. The three-compartment model may be a useful concept to measure body composition changes in both healthy and sick persons. 相似文献
1000.
Establishing orthotopic transplanted models of human pancreatic cancer in nude mice and study on their biological properties] 总被引:1,自引:1,他引:0
Two cell lines of human pancreatic cancer have been established, which can be successfully transplanted into pancreas of nude mice, the first of this kind of cell lines in China. Fresh specimens human of pancreatic cancer taken surgically were transplanted in the pancreas of pure line BALB/C-nu/nu nude mice. The transplanted tumours grew and reproduced successfully, and were named PINMP-1 and PINMP-2, respectively. So far, 9 generations of PINMP-1 and 6 generations of PINMP-2 were obtained. Their biological properties, ways of invasion and metastasis and morphological characteristics under light and electron microscope were studied. The results showed a 95%-100% transplanting success rate, with the success rate of transplanting from tissues revivified from the liquid nitrogen preservation being 100%. Both of the lines could produce large amount of CEA, and chromosome analysis confirmed that they had retained a karyotype of the human cancer cells. In nude mice transplanted with the tumours, metastasis could be found in the lymph nodes, lungs and livers. Metastasis via lymphatic channels and blood vessels were also demonstrated. The pathological and ultrastructural examination confirmed that the transplanted tumours had identical characteristics as their donor tumours. The transplanted cells grew independently in the pancreas of the nude mice, making a better model for study on tumour invasion and metastasis than subcutaneously transplanted tumours. This indicated that the microenvironment in the transplantation site had certain influence on the biological behavior of the transplanted tumours. The models could be used in the study on the invasion, metastasis and experimental therapy of pancreatic carcinomas. 相似文献