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111.
The unique organism project was designed as a culminating assessment for a biological classification unit in a middle school setting. Students developed a model to represent their unique organism. Using the model, students were required to demonstrate how their unique organism interacts with its environment, and how its internal and external structure and organization allowed it to carry out those interactions. The NGSS Cross Cutting Concepts of structure and function, systems, and system models along with the Science & Engineering Practice of constructing models were integrated and emphasized throughout the unit. 相似文献
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The Ca2+-dependent regulator protein of cyclic nucleotide phosphodiesterase was labeled with 125I to the extent of 1 mol of monoiodotyrosine per mol. The iodinated protein showed a small decrease in affinity for phosphodiesterase but gave the same maximal level of activation of the enzyme as did the unmodified regulator protein. Iodinated regulator protein formed complexes with both highly purified cyclic nucleotide phosphodiesterase and phosphodiesterase inhibitory protein in the presence but not in the absence of Ca2+ as demonstrated by ultracentrifugation in glycerol gradients. Cross-linking experiments indicate that the Ca2+-dependent regulator protein interacts with the large subunit of the inhibitory protein. 相似文献
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Tokumi Maruyama Kunihiko Utzumi Yoshiko Sato Douglas D. Richman 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):527-537
Abstract 3′,5′-Di-O-protected 6-chloropurine arabinoside 4b was treated with diethylaminosulfur trifluoride (DAST) and subsequently deprotected with pyridinium p-toluenesulfonate to give 6-chloropurine 2′-deoxy-2′-fluororiboside 6a. The displacement with nucleophile afforded the 6-substituted congener 6b-e. Treatment of 5′-O-protected 6-chloropurine arabinoside 3c with DAST gave lyxoepoxide 7. 相似文献
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Town L McGlinn E Davidson TL Browne CM Chawengsaksophak K Koopman P Richman JM Wicking C 《PloS one》2011,6(9):e25228
The Tmem26 gene encodes a novel protein that we have previously shown to be regulated by hedgehog signalling in the mouse limb. We now report that Tmem26 expression is spatially and temporally restricted in other regions of the mouse embryo, most notably the facial primordia. In particular, Tmem26 expression in the mesenchyme of the maxillary and nasal prominences is coincident with fusion of the primary palate. In the secondary palate, Tmem26 is expressed in the palatal shelves during their growth and fusion but is downregulated once fusion is complete. Expression was also detected at the midline of the expanding mandible and at the tips of the eyelids as they migrate across the cornea. Given the spatio-temporally restricted expression of Tmem26, we sought to uncover a functional role in embryonic development through targeted gene inactivation in the mouse. However, ubiquitous inactivation of Tmem26 led to no overt phenotype in the resulting embryos or adult mice, suggesting that TMEM26 function is dispensable for embryonic survival. 相似文献
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George K. Hightower Susanne J. May Josué Pérez-Santiago Mary E. Pacold Gabriel A. Wagner Susan J. Little Douglas D. Richman Sanjay R. Mehta Davey M. Smith Sergei L. Kosakovsky Pond 《PloS one》2013,8(6)