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921.
Oliver E. Hutt Jun Inagaki Bollu S. Reddy Sajiv K. Nair Emily A. Reiff John T. Henri Jack F. Greiner David G. VanderVelde Ting-Lan Chiu Elizabeth A. Amin Richard H. Himes Gunda I. Georg 《Bioorganic & medicinal chemistry letters》2009,19(12):3293-3296
The total synthesis of 22-(3-azidobenzoyloxy)methyl epothilone C is described as a potential photoaffinity probe to elucidate the β-tubulin binding site. A sequential Suzuki-aldol-Yamaguchi macrolactonization strategy was utilized employing a novel derivatized C1–C6 fragment. The C22-functionalized analog exhibited good activity in microtubule assembly assays, but cytotoxicity was significantly reduced. Molecular modeling simulations indicated that excessive steric bulk in the C22 position is accommodated by the large hydrophobic pocket of the binding site. Photoaffinity labeling studies were inconclusive suggesting non-specific labeling. 相似文献
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924.
Luc Brendock Osman M. Alit Dirk Claeys Asim El Moghraby Henri J. Dumont 《Hydrobiologia》1989,185(2):145-151
A lightweight LRF 104 laser rangefinder was used in lake mapping. As an example, the Malha crater (Darfur, West-Sudan), containing
a lake, springs, wells, and vegetation, was mapped. 相似文献
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926.
Streptocephalus caljoni n.sp. (Crustacea: Anostraca) from Burundi and analysis of its limb structure
Streptocephalus caljoni n. sp. from Burundi is described. It is related to Streptocephalus trifidus, but differs from it and other Streptocephalus in the cheliform hand of the male antenna II. We also analyse the morphology of the setae on the endo- and exopodite of the fifth trunk limb, using light- and scanning electron microscopy. This analysis reveals additional differences between the two related species, and is a useful tool in the study of the taxonomy of the Anostraca. 相似文献
927.
Bliziotis Nikolaos G. Engelke Udo F. H. Aspers Ruud L. E. G. Engel Jasper Deinum Jaap Timmers Henri J. L. M. Wevers Ron A. Kluijtmans Leo A. J. 《Metabolomics : Official journal of the Metabolomic Society》2020,16(5):1-1
Metabolomics - Understanding the interaction between organisms and the environment is important for predicting and mitigating the effects of global phenomena such as climate change, and the fate,... 相似文献
928.
Phosphomannose isomerase deficiency: a carbohydrate-deficient glycoprotein syndrome with hepatic-intestinal presentation. 总被引:8,自引:0,他引:8 下载免费PDF全文
929.
Henri Lechenault Francine Wrisez Jean Mellinger 《Environmental Biology of Fishes》1993,38(1-3):241-252
Synopsis Using plastic embedding techniques and semithin sections, in order to overcome the difficult sectioning of yolky eggs, we have been able to carry out histological study of the external yolksac from fertilization until birth in the oviparous dogfishScyliorhinus canicula. The endoderm and its contacting giant yolk nuclei remained very flat, seemingly inactive, during the larger part of development. They became activated only when the external yolksac (EYS) began to shrink. This activation increased along a vegetal-animal gradient in the EYS, but it was essentially restricted to the parts located near the yolk stalk. A statistical study of oocyte, yolk, embryo and newborn fresh and dry weights confirmed that the mass of dry tissue in the embryo (30mg) and in EYS wall (<1 mg) at mid-development were still very low compared to 0.8–1.5 g mass of yolk available for development. This explains why yolk weight remained practically the same during the first half of development. The end of this first period was marked by entry into the pre-hatching state at 85–115 days under laboratory conditions (14–16°C). At this time, yolk began to enter the spiral gut, where it was digested during the second half of development and during one week period after eclosion. Eclosion occurred 170–220 days after egg laying or extraction from oviduct. Two internal storage organs were studied biometrically in the newborn: the internal yolksac (IYS), and the liver, which was fully developed at birth. Both IYS and liver dry weights corresponded to about 10% of the original yolk, while the gut was only 2%, and the rest of the newborn body 58%. Thus, about 20% of yolk dry mass was consumed during development, a figure that is low for oviparous animals. 相似文献
930.