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21.
Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane
fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity
induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression
of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that
the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs
against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However,
the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated
that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding
isotypic and idiotypic determinants of IgM on the cell membrane. 相似文献
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23.
J F Cai 《中华整形烧伤外科杂志》1989,5(3):190-2, 238
Since 1985, on the basis of anatomic study of dorsal pedal artery, thumb and radial side of palm reconstruction have been successfully performed in one stage by using opposite composite dorsal pedal flap including the second toe, the second metatarsal and the first toe web. Because they were all distributed by dorsal pedal artery and great saphenous vein, dissecting these tissues was not difficult. Good function and cosmetic appearance were achieved following reconstruction. 相似文献
24.
目的评价美国强生VITROS250全自动干化学分析仪器。方法运用相关统计学方法对VITROS250全自动干化学分析仪的精密度、相关性、抗胆红素干扰方面进行分析。结果VITROS250全自动干化学分析仪精密度高,回收率高,相关性好,抗干扰能力强。结论VITROS250全自动干化学分析仪适用于临床实验诊断中心(检验科)急诊化验室生化项目的检测。 相似文献
25.
A Batak Indonesian from North Sumatra with hemoglobin (Hb) D Punjab (alpha 2 beta 2 121----Gln) and hemoglobin Constant Spring (Hb CoSp) is described. The 24-year-old man did not have clinical symptoms, and his hematological indices were normal. However, he had a persistent slight elevation of fetal hemoglobin level. His mother and his brother were heterozygous for Hb D Punjab; his father had Hb CoSp trait. A sister did not have any abnormal hemoglobin. To show the exact molecular defect leading to the synthesis of Hb CoSp in this family, genomic DNA from the father was analyzed by hybridization with synthetic oligonucleotides. Genomic DNA was digested with Sst I and Hind III producing a 1.05-kb fragment from the 3' end segment of the alpha 2-globin gene, including the termination codon. Two nonadecamers were synthesized to serve as probes: one, entirely homologous to the normal 3' end of alpha 2A-globin gene sequence, including the termination codon TAA, the other different from it by a replacement of the T in the termination codon TAA with C, changing it to CAA, the codon for the amino acid glutamine. DNA from normal controls gave a positive signal with the normal alpha 2TAA oligonucleotide probe but negative with the alpha 2 CAA probe. The father of propositus who had Hb CoSp trait gave a positive signal with the normal alpha 2TAA oligonucleotide probe as well as with the alpha 2CAA oligonucleotide probe, showing him to be heterozygous for the alpha 2CAA-globin gene. This result shows that the Hb CoSp in the Batak family is indeed due to a replacement of T by C in the TAA termination codon of the alpha 2-globin gene changing it to CAA the condon for glutamine. This explains the resulting readthrough of the untranslated sequence of the mRNA. 相似文献
26.
CAILU LIUSHUZHENG 《Biomedical and environmental sciences : BES》1992,5(1):46-52
Human lymphocytes pre-exposed to 10 mGy or 50mGy of X-rays become less sensitive to subsequent large dose irradiation,exhibited lower rate of chromosome aberration than expected.This adaptive response could be inhibited by cycloheximide,a protein synthesis inhibitor for successive 2h period ranging from 0.5h before to 4h after the low dose exposure,indicating that the adaptive response was directly related with the protein synthesis. 相似文献
27.
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29.
Most studies have been unable to identify reliable acoustic cues for the recognition of the English nonsibilant fricatives [see text]. The present study was designed to test the extent to which the perception of these fricatives by normal-hearing adults is based on other sources of information, namely, linguistic context and visual information. In Experiment 1, target words beginning with /f/, /theta/, /s/, or [see text] were preceded by either a semantically congruous or incongruous precursor sentence. Results showed an effect of linguistic context on the perception of the distinction between /f/ and /theta/ and on the acoustically more robust distinction between /s/ and [see text]. In Experiment 2, participants identified syllables consisting of the fricatives [see text] paired with the vowels /i, a, u/. Three conditions were contrasted: Stimuli were presented with (a) both auditory and visual information, (b) auditory information alone, or (c) visual information alone. When errors in terms of voicing were ignored in all 3 conditions, results indicated that perception of these fricatives is as good with visual information alone as with both auditory and visual information combined, and better than for auditory information alone. These findings suggest that accurate perception of nonsibilant fricatives derives from a combination of acoustic, linguistic, and visual information. 相似文献
30.
现将本院2006年1月-2006年12月54例经DSA全脑造影及栓塞术的麻醉处理总结如下。
1资料与方法
1.1一般资料
本组54例患者中,男29例,女25例,年龄11-70岁,ASAⅡ-Ⅲ级,急诊11例。术前昏迷5例,术中动脉瘤破裂2例。 相似文献