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991.
介绍一种简单、经济的同工酶染色方法:用熔化的0.4%琼脂糖处理滤纸备用,染色前将滤纸浸于同工酶染色液中,染色时将滤纸盖在聚丙烯酸胺胶上,然后将胶放在有盖塑料盒中保温染色,染色时间要比普通方法略长。染色后将胶和滤纸移入固定液中用镊子除去滤纸. 相似文献
992.
Kazuo Sano Joji Sekine Tsugio Inokuchi Michael B. Pe Guowu Ma 《Biotechnic & histochemistry》1996,71(6):273-277
A rapid enhanced polymer one-step staining for proliferating cell nuclear antigen [EPOS-PCNA) in formalin fixed, paraffin embedded sections of tongue squamous cell carcinoma is described. EPOS-PCNA was compared with PCNA immunohistochemistry using the avidin-biotin complex (ABC) method, with or without autoclave pretreatment. Significant correlation of PCNA labeling index (percentage of labeled cells/total cells counted) was observed between EPOS-PCNA and the immunohistochemical protocol using autoclave pretreatment. We consider this method a reliable, timesaving technique that would be useful in quantitative histopatbology and in performing double immunostaining. 相似文献
993.
A method is described for staining lipid in fourth-stage dispersal juvenile nematodes fixed with formal-acetic fixative (FA4:1). Bursaphelenchus xylophilus fourth-stage dispersal juveniles were fixed with hot FA4:1 for 24 hours, excess fixative was removed, and a solution of saturated oil red O in 96% ethanol added and allowed to sit for 25 minutes at 60 C. Excess oil red O was removed, nematodes were washed twice with 70% ethanol, and were processed to pure glycerin. Lipid droplets within the nematodes were viewed by light microscopy and appeared as dark red spheres of various sizes. Computerized image analysis was used to quantify lipid droplet area. 相似文献
994.
François Leitner Sylvain Paillasson Xavier Ronot Jacques Demongeot 《Acta biotheoretica》1995,43(4):299-317
Increasing interest has been paid to applications of fluorescence measurements to analyze physiological mechanisms in living cells. However, few studies have taken advantage of DNA quantification by fluorometry for dynamic assessment of chromatin organization as well as cell motion during the cell cycle. This approach involves both optimal conditions for DNA staining and cell tracking methods. In this context, this report describes a stoichiometric method for nuclear DNA specific staining, using the bisbenzimidazole dye Hoechst 33342 associated with verapamil, a calcium membrane channel blocker. This method makes it possible to correlate variations of nuclear DNA content with cell motion in cells that are maintained alive. Motion measurement is the second goal of this paper and it explains the snake-spline method, and the associated cell following method. 相似文献
995.
细胞化学研究文献报导,巨噬细胞中过氧化物酶的活性有明显的差异,只有部分巨噬细胞过氧化物酶呈阳性反应。本文用淀粉、白喉类毒素和卡介苗分别诱导和活化小鼠腹腔巨噬细胞,进行过氧化物酶反应,并以7690-Xu荧光染液复染后证明,酶反应阳性细胞呈蓝色荧光,而酶反应阴性细胞为淡蓝绿色和黄色荧光。实验表明,过氧化物酶阳性的巨噬细胞是分化程度低的幼稚细胞,因此,过氧化物酶的活性可作为低分化的巨噬细胞的一种标志酶。同时,本文用免疫荧光单克隆抗体间接染色法观察了三种物质诱导和活化的异质性荧光染色的巨噬细胞的分泌功能。 相似文献
996.
997.
Various portions of the splanchnopleural mesoderm lateral to the somites of 1.5-day chick embryos were marked in ovo by local injection of Dil, and the distribution of the labelled cells in the digestive-tract mesoderm formed after 3 days' reincubation was analysed. The presumptive area of the digestive organs was confined to bands of splanchnic mesoderm lying lateral to the somites, on both sides, with a width two or three times that between the midline of the embryo and the lateral edge of the somite. Each band generally contributed cells to its own side of the digestive-tract mesoderm, except for the region around the bile duct. The anterior and posterior portion of the pre-gut area contributed cells to the anterior and posterior region of the digestive tract, respectively, but label originating from the portion furthest from the somite took the more ventral and posterior position. Thus, the presumptive areas of the respective digestive organs were located anteroposteriorly in the same order as in the digestive tract with their boundaries lying oblique to the embryonic axis. 相似文献
998.
In Papanicolaou-stained smears certain structures such as nucleoli, Pneumocystis carinii , Charcot-Leyden crystals, bacteria and fungi show a brilliant fluorescence. the morphological characteristics of microorganisms which can be detected by this system, especially mycobacteria, are described. This screening method offers the possibility of providing the clinician with a provisional diagnosis within hours. Proof of the nature of the organisms should be obtained by culture. 相似文献
999.
A purification procedure and partial characterization of bovine pituitary fibroblast growth factor (FGF) are described. The steps of the published methods [3,4] which yield inhomogeneous material, were retained, with modifications. The final isolation, with an additional purification of ~20-fold, was achieved by electro-phoresis in polyacrylamide gels at acid pH. The mitogenic peptide has a molecular weight of 14,500–15,00 as determined on SDS gels, chromatographs as a monomer in nondenaturing conditions, and is active at the picomolar level in effecting the incorporation of 3H-thymidine in Balb/c 3T3 cells. A preliminary amino acid composition is presented. 相似文献
1000.
Summary Electrical stimulation (five minutes) of the olfactory tract in Clarias batrachus results in total degranulation of the neurons of the pars magnocellularis (PMC), while a ten-minute treatment is required for degranulation of the entire nucleus preopticus (NPO). The preoptico-neurohypophysial tract (PNT) and neurohypophysis (NH) of these animals are feebly stained. By 15 minutes of stimulation the neurosecretory material (NSM) is depleted from the entire system; only a few granules may be present in the PNT and NH. A delay for 30 minutes after a 15-minute stimulation causes restoration of NSM in the NH and PNT, while a 60-minute delay results in a higher degree of accumulation of NSM.
Zusammenfassung Eine 5 min dauernde elektrische Stimulierung des Tractus olfactorius von Clarias batrachus bewirkt eine vollständige Entgranulierung der sekretorischen Neurone der Pars magnocellularis nuclei praeoptici (PMC), während für die Entgranulierung des ganzen Nucleus praeopticus (NPO) eine Stimulierungsdauer von 10 min erforderlich ist. Die Neurosekretfärbung des Tractus praeoptico-neurohypophyseus (PNT) und der Neurohypophyse (NH) fällt bei diesen Versuchstieren mäßig aus. Nach 15 minütiger Stimulierung ist das färbbare Material (NSM) im ganzen neurosekretorischen System weitgehend abgebaut; nur noch wenige Granula finden sich im PNT und in der NH. Eine Ruhephase von 30 min, die auf eine 15 minütige Stimulierung folgt, führt zum Wiederauftreten des NSM in der NH und im PNT, während nach einer 60 minütigen Pause die Menge des NSM weiter zunimmt.相似文献