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141.
KJ Aufderheide 《Biotechnic & histochemistry》2016,91(5):352-356
The original ammoniacal silver carbonate staining technique and subsequent modification developed by Fernández-Galiano are useful for investigating ciliate protozoan systematics and/or ciliate cortical structure and morphogenesis. The technique is complicated, however, by both uncertainties arising from the need to count drops of reagents and subjective control of the staining intensity. I have resolved these complications by defining volumes of reagents rather than using drops and by defining a range of staining times. I also comment on various steps of the techniques. My techniques are simplified and refined to produce consistent, high quality staining results. 相似文献
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Many sources of fluctuation contribute to the functional magnetic resonance imaging (fMRI) signal, complicating attempts to infer those changes that are truly related to brain activation. Unlike methods of analysis of fMRI data that test the time course of each voxel against a hypothesized waveform, data-driven methods, such as independent component analysis and clustering, attempt to find common features within the data. This exploratory approach can be revealing when the brain activation is difficult to predict beforehand, such as with complex stimuli and internal shifts of activation that are not time-locked to an easily specified sensory or motor event. These methods can be further improved by incorporating prior knowledge regarding the temporal and spatial extent of brain activation. 相似文献
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Cockerill S Stubberfield C Stables J Carter M Guntrip S Smith K McKeown S Shaw R Topley P Thomsen L Affleck K Jowett A Hayes D Willson M Woollard P Spalding D 《Bioorganic & medicinal chemistry letters》2001,11(11):1401-1405
Described herein is the design and synthesis of indazolylaminopyridopyrimidines and quinazolines as inhibitors of the class 1 tyrosine kinase receptor family. Data is presented for N(4)-(1-benzyl-1H-indazol-5-yl)-N(6),N(6)-dimethylpyrido[3,4-d]pyrimidine-4,6-diamine 3B. This compound inhibited EGFr and c-erbB-2 enzymes selectively over other kinases. It inhibited the proliferation of a range of tumour cell lines in vitro and the growth of BT474 xenografts in SCID mice. 相似文献
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Summary The prolactin-producing cells are the first hormone-producing cells of the pars distalis to be differentiated within Ambystoma gracile. They first appear when the larvae attain a length of approximately 3.0 cm snout to vent length (SVL). Thyrotropes are observed as the next chromophilic cells to appear, and they occur when the larvae are approximately 4.5 cm SVL. Both thyrotropes and lactotropes increase in numbers until metamorphosis. Gonadotropes begin to appear when larvae attain a size of 5.0 cm SVL and become extremely abundant when larvae are in excess of 7.0 cm SVL. Animals, generally, exhibit the greatest number of thyrotropes just prior to the mean size for metamorphosis, and metamorphosing animals exhibit a dramatic reduction in the number of thyrotropes. Neotenous larvae have an abundant number of thyrotropes which are mainly located along the caudal periphery of the pituitary. 相似文献
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