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排序方式: 共有410条查询结果,搜索用时 15 毫秒
91.
Sperandio D Tai VW Lohman J Hirschbein B Mendonca R Lee CS Spencer JR Janc J Nguyen M Beltman J Sprengeler P Scheerens H Lin T Liu L Gadre A Kellogg A Green MJ McGrath ME 《Bioorganic & medicinal chemistry letters》2006,16(15):4085-4089
The synthesis of novel [1,2,4]oxadiazoles and their structure-activity relationship (SAR) for the inhibition of tryptase and related serine proteases is presented. Elaboration of the P'-side afforded potent, selective, and orally bioavailable tryptase inhibitors. 相似文献
92.
John Gray Michael Bevan Thomas Brutnell C. Robin Buell Karen Cone Sarah Hake David Jackson Elizabeth Kellogg Carolyn Lawrence Susan McCouch Todd Mockler Stephen Moose Andrew Paterson Thomas Peterson Daniel Rokshar Glaucia Mendes Souza Nathan Springer Nils Stein Marja Timmermans Guo-Liang Wang Erich Grotewold 《Plant physiology》2009,149(1):4-6
93.
Qianbin Li Adnan Al-Ayoubi Tailiang Guo Hui Zheng Aurijit Sarkar Tri Nguyen Scott T. Eblen Steven Grant Glen E. Kellogg Shijun Zhang 《Bioorganic & medicinal chemistry letters》2009,19(21):6042-6046
A series of analogs of 3-(2-amino-ethyl)-5-(4-ethoxy-benzylidene)-thiazolidine-2,4-dione, a putative substrate-specific ERK1/2 inhibitor, were synthesized and biologically characterized in human leukemia U937 cells to define its pharmacophore. It was discovered that shift of ethoxy substitution from the 4- to the 2-position on the phenyl ring significantly improved functional activities of inhibiting cell proliferation and inducing apoptosis. This may provide access to a new lead for developing ERK1/2 substrate-specific inhibitors. 相似文献
94.
Leebens-Mack J Vision T Brenner E Bowers JE Cannon S Clement MJ Cunningham CW dePamphilis C deSalle R Doyle JJ Eisen JA Gu X Harshman J Jansen RK Kellogg EA Koonin EV Mishler BD Philippe H Pires JC Qiu YL Rhee SY Sjölander K Soltis DE Soltis PS Stevenson DW Wall K Warnow T Zmasek C 《Omics : a journal of integrative biology》2006,10(2):231-237
95.
Timothy J. Gallaher Paul M. Peterson Robert J. Soreng Fernando O. Zuloaga De‐Zhu Li Lynn G. Clark Christopher D. Tyrrell Cassiano A.D. Welker Elizabeth A. Kellogg Jordan K. Teisher 《植物分类学报:英文版》2022,60(3):522-569
Grasses are widespread on every continent and are found in all terrestrial biomes. The dominance and spread of grasses and grassland ecosystems have led to significant changes in Earth′s climate, geochemistry, and biodiversity. The abundance of DNA sequence data, particularly chloroplast sequences, and advances in placing grass fossils within the family allows for a reappraisal of the family′s origins, timing, and geographic spread and the factors that have promoted diversification. We reconstructed a time-calibrated grass phylogeny and inferred ancestral areas using chloroplast DNA sequences from nearly 90% of extant grass genera. With a few notable exceptions, the phylogeny is well resolved to the subtribal level. The family began to diversify in the Early–Late Cretaceous (crown age of 98.54 Ma) on West Gondwana before the complete split between Africa and South America. Vicariance from the splitting of Gondwana may be responsible for the initial divergence in the family. However, Africa clearly served as the center of origin for much of the early diversification of the family. With this phylogenetic, temporal, and spatial framework, we review the evolution and biogeography of the family with the aim to facilitate the testing of biogeographical hypotheses about its origins, evolutionary tempo, and diversification. The current classification of the family is discussed with an extensive review of the extant diversity and distribution of species, molecular and morphological evidence supporting the current classification scheme, and the evidence informing our understanding of the biogeographical history of the family. 相似文献
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Previous observations have indicated that specific behavioral responses to anxiogenic stimuli emerge over adolescent development in male rats and that gonadal androgens during puberty are essential for this emergence. The objective of the current study was to evaluate mechanisms via which androgens might be organizing the brain during adolescence for appropriate mature adaptive responses. Male rats were exposed to fadrozole (an aromatase inhibitor, 5 mg/kg), flutamide (an androgen receptor antagonist, 10 mg/kg), or MK-434 (a 5 alpha-reductase inhibitor, 10 mg/kg) from day 29 to 60 and tested for environment-specific social interaction (SI) at 60 days of age. The emergence of adult-typical SI was impaired by exposure to the aromatase inhibitor and to the antiandrogen, whereas exposure to the 5 alpha-reductase inhibitor was without effect. Peripheral indices of drug effects indicated that the respective mechanisms had been altered by the different compounds. These results suggest that testosterone induction of aromatase is critical for the organization of mature SI behavior in male rats over adolescent development. 相似文献
98.
Recovery, Bioaccumulation, and Inactivation of Human Waterborne Pathogens by the Chesapeake Bay Nonnative Oyster, Crassostrea ariakensis 下载免费PDF全文
Thaddeus K. Graczyk Autumn S. Girouard Leena Tamang Sharon P. Nappier Kellogg J. Schwab 《Applied microbiology》2006,72(5):3390-3395
The introduction of nonnative oysters (i.e., Crassostrea ariakensis) into the Chesapeake Bay has been proposed as necessary for the restoration of the oyster industry; however, nothing is known about the public health risks related to contamination of these oysters with human pathogens. Commercial market-size C. ariakensis triploids were maintained in large marine tanks with water of low (8-ppt), medium (12-ppt), and high (20-ppt) salinities spiked with 1.0 × 105 transmissive stages of the following human pathogens: Cryptosporidium parvum oocysts, Giardia lamblia cysts, and microsporidian spores (i.e., Encephalitozoon intestinalis, Encephalitozoon hellem, and Enterocytozoon bieneusi). Viable oocysts and spores were still detected in oysters on day 33 post-water inoculation (pwi), and cysts were detected on day 14 pwi. The recovery, bioaccumulation, depuration, and inactivation rates of human waterborne pathogens by C. ariakensis triploids were driven by salinity and were optimal in medium- and high-salinity water. The concentration of human pathogens from ambient water by C. ariakensis and the retention of these pathogens without (or with minimal) inactivation and a very low depuration rate provide evidence that these oysters may present a public health threat upon entering the human food chain, if harvested from polluted water. This conclusion is reinforced by the concentration of waterborne pathogens used in the present study, which was representative of levels of infectious agents in surface waters, including the Chesapeake Bay. Aquacultures of nonnative oysters in the Chesapeake Bay will provide excellent ecological services in regard to efficient cleaning of human-infectious agents from the estuarine waters. 相似文献
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