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31.
Makoto Suematsu Shigenari Houzawa Soichiro Miura Hiroshi Nagata Tetsuji Kitahora Tetsuo Morishita Chikara Oshio Masaharu Tsuchiya 《Luminescence》1989,4(1):531-534
Reaction difference of oxyradical generation and luminol-dependent photoemission of zymosan- and phorbol ester-treated neutrophils were investigated using a conventional photomultiplier and ultrasensitive photonic imaging technique. Zymosan-treated cells released a concentrated photonic burst corresponding to the cellular distribution. In contrast, phorbol ester-treated cells produced a negligible level of photoemission, and the additional application of Ca2+ ionophore enhanced the photonic burst, which was gradually spread out into extracellular space. Serine protease inhibitors did not attenuate PMA-induced chemiluminescence but did attenuate zymosan-induced chemiluminescence. This suggests the involvement of serine protease in the respiratory burst of phagocytizing neutrophils. 相似文献
32.
We describe the application of a CCD Imaging Luminometer (CCDIL) for the detection and quantitation of rapid, simultaneous, peroxidase-linked chemiluminescent immunoassays of multiple samples of human serum alphafetoprotein (AFP). Results from some analogous immunoassays (total IgE, and thyroid stimulating hormone (TSH)) are included for comparison. Values for precision and antigen concentration obtained using the CCDIL and colorimetric versions of the immunoassays, on human serum samples, were in good agreement. The flexibility of the CCDIL is demonstrated; its ability to detect and quantitate antigen (particularly AFP) on a variety of solid phases is indicated. The work on the AFP immunoassays illustrates not only the flexibility of the CCDIL for sample presentation on a variety of solid phase systems, but also some relative merits of such systems. 相似文献
33.
本文系统地研究了广东地区汉族人群中FⅧ:C基因内BclⅠ,XbaⅠ和BgⅡ位点RFLP的基因频率。多态性位点BclⅠ,XbaⅠ及BglⅠ的切点阳性率分别为63.5%、43.5%和100%。对Bcll和Xbal多态性切点连锁情况研究显示,19.5%的Bcll切点阳性纯合子为Xbal切点杂合子,证明联合应用此两位点RFLP可以把甲型血友病基因连锁分析的有效率提高到65.9%。用RFLP连锁分析对两例甲型血友病家系中的女性进行了致病基因携带者检测,对另一例家系进行了基因产前诊断。 相似文献
34.
35.
The Biology of the Tospoviruses 总被引:1,自引:0,他引:1
The tospoviruses are a diverse, cosmopolitan and economically important genus of plant viruses. In the recent past, interest in the tospoviruses has been rekindled with the resurgence and expansion of tomato spotted wilt virus and the appearance of new tospoviruses, including impatiens necrotic spot. This renewed interest in the tospoviruses, accompanied with the many recent advances in plant virology techniques, particularly those utilising molecular biology, have resulted in a rapid growth of our understanding of these viruses. This paper provides a review of the tospoviruses, encompassing all the major aspects of their biology, including the recent changes in the classification of the genus and current knowledge on molecular biology, vector relations, control and diagnosis. 相似文献
36.
二核苷酸重复多态性的非同位素检测及其在基因诊断中的应用 总被引:9,自引:1,他引:8
本文报道了一种检测二核苷酸重复多态性的简便的非同位素法,利用重复序列两侧的特异引物进行PCR扩增,产生的等位片段在薄层变性聚丙烯酰胺凝胶电泳上分离,再用灵敏的银染法显色。该方法不需要标记PCR产物,简便、快速,分辨率可达1bp,并可用多对引物同时进行多重PCR分析。用此方法对DMD家系成员dystrophin基因的5'-脑型外显子止游区和3'-非翻译区的两个(CA)。位点进行了扩增片段长度多态性分 相似文献
37.
Calcium ions play critical roles in neuronal differentiation. We have recorded transient, repeated elevations of calcium in embryonic Xenopus spinal neurons over periods of 1 h in vitro and in vivo, confocally imaging fluo 3-loaded cells at 5 s intervals. Calcium spikes and calcium waves are found both in neurons in culture and in the intact spinal cord. Spikes rise rapidly to approximately 400% of baseline fluorescence and have a double exponential decay, whereas waves rise slowly to approximately 200% of baseline fluorescence and decay slowly as well. Imaging of fura 2-loaded neurons indicates that intracellular calcium increases from 50 to 500 nM during spikes. Both spikes and waves are abolished by removal of extracellular calcium. Developmentally, the incidence and frequency of spikes decrease, whereas the incidence and frequency of waves are constant. Spikes are generated by spontaneous calcium-dependent action potentials and also utilize intracellular calcium stores. Waves are produced by a mechanism that does not involve classic voltage-dependent calcium channels. Spikes are required for expression of the transmitter GABA and for potassium channel modulation. Waves in growth cones are likely to regulate neurite extension. The results demonstrate the roles of a novel signaling system in regulating neuronal plasticity, that operates on a time scale 104 times slower than that of action potentials. © 1995 John Wiley & Sons, Inc. 相似文献
38.
Within the genus Mesocyclops the thermocyclopoides species-group is defined on the basis of the presence of spiniform armature on the maxillar coxa. Examination of nineteen, mainly Palaeotropical species of Mesocyclops and nine representatives of the closely related genus Thermocyclops revealed, that the coxal part of the maxillar syncoxa of the species recently unified in the thermocyclopoides group is adorned with distinct rows of big spinules on its frontal surface. This character, with only one known exception in South Indian M. cf. papuensis, is absent in other species of Mesocyclops and all the Thermocyclops studied here. These species have no spinules on the maxillar coxa at all or very tiny scattered ones. 相似文献
39.
L. Wojnowski W. T. Mason A. Schwab H. Oberleithner 《The Journal of membrane biology》1994,138(2):143-149
We investigated the relationship between intracellular Ca2+ and pH homeostasis in Madin-Darby canine kidney-focus (MDCK-F) cells, a cell line exhibiting spontaneous oscillations of intracellular Ca2+ concentration (Ca
i
2+
). Ca
i
2+
and intracellular pH (pH
i
) were measured with the fluorescent dyes Fura-2 and BCECF by means of video imaging techniques. Ca2+ influx from the extracellular space into the cell was determined with the Mn2+ quenching technique. Cells were superfused with HEPES-buffered solutions. Under control conditions (pH 7.2), spontaneous Ca
i
2+
oscillations were observed in virtually all cells investigated. Successive alkalinization and acidification of the cytoplasm induced by an ammonia ion prepulse had no apparent effect on Ca
i
2+
oscillations. On the contrary, changes of extracellular pH value strongly affected Ca
i
2+
oscillations. Extracellular alkalinization to pH 7.6 completely suppressed oscillations, whereas extracellular acidification to pH 6.8 decreased their frequency by 40%. Under the same conditions, the respective pH
i
changes were less than 0. 1 pH units. However, experiments with the Mn2+ quenching technique revealed that extracellular alkalinization significantly reduced Ca2+ entry from the extracellular space. Large increases of Ca
i
2+
triggered by the blocker of the cytoplasmic Ca2+-ATPase, thapsigargin, had no effect on pH
i
We conclude: intracellular Ca2+ homeostasis in MDCK-F cells is pH dependent. pH controls Ca2+ homeostasis mainly by effects on the level of Ca2+ entry across the plasma membrane. On the contrary, the intracellular pH value seems to be insensitive to rapid changes of Ca
i
2+
.The project was supported by the Deutsche Forschungsgemeinschaft, SFB-176 (A6) and by the Jubilämusstiftung of the University of Würzburg.The authors gratefully acknowledge the valuable discussions with Drs. M.J. Berridge, M. Carew, I. Davidson, G. Law and B. Somasundraman. We are grateful to Applied Imaging for financial and technical support and to the Medical Research Council for financial support. 相似文献
40.
We examined the dose response, time course and reversibility of the effect of methyl 2-tetradecylglycidate (McN-3716, methyl palmoxirate or MEP), an inhibitor of -oxidation of fatty acids, on incorporation of radiolabeled palmitic acid ([U-14C]PA) from plasma into brain lipids of awake rats. MEP (0.1, 1 and 10 mg/kg) or vehicle was administered intravenously from 10 min to 72 hr prior to infusion of [U-14C]PA. Two hr pretreatment with MEP (0.1 to 10 mg/kg) increased brain organic radioactivity 1.2 to 1.8 fold and decreased brain aqueous radioactivity by 1.2 to 3.0 fold when compared to control values. At 10 mg/kg, MEP significantly increased brain organic fraction from 40% in controls to 85%, 30 min to 6 hr pretreatment, and resulted in a redistribution of the radiolabeled fatty acid toward triacylglycerol. MEP changed the lipid/aqueous brain ratio of incorporated [U-14C]PA from 0.67 to 5.7. The incorporation rate coefficient, k*, was significantly increased by MEP (10 mg/kg) at 2 hr (31%), 4 hr (59%) and 6 hr (34%). All effects were reversed by 72 hr, consistent with a half-life of 2 days for carnitine palmitoyl transferase I. These results indicate that intravenous MEP may be used with [1-11C]palmitic acid for studying brain lipid metabolism in vivo by positron emission tomography, as it significantly reduces the large unincorporated aqueous fraction that would result in high background radioactivity. 相似文献