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131.
P K Buxton 《BMJ (Clinical research ed.)》1988,296(6617):257-261
132.
133.
J. D. Buxton 《BMJ (Clinical research ed.)》1940,2(4170):802-803
134.
135.
Tsutomu Akama Yong-Kang Zhang Yvonne R. Freund Pamela Berry Joanne Lee Eric E. Easom Robert T. Jacobs Jacob J. Plattner Michael J. Witty Rosemary Peter Tim G. Rowan Kirsten Gillingwater Reto Brun Bakela Nare Luke Mercer Musheng Xu Jiangong Wang Hao Liang 《Bioorganic & medicinal chemistry letters》2018,28(1):6-10
Novel l-valinate amide benzoxaboroles and analogues were designed and synthesized for a structure-activity-relationship (SAR) investigation to optimize the growth inhibitory activity against Trypanosoma congolense (T. congolense) and Trypanosoma vivax (T. vivax) parasites. The study identified 4-fluorobenzyl (1-hydroxy-7-methyl-1,3-dihydrobenzo[c][1,2]oxaborole-6-carbonyl)-l-valinate (5, AN11736), which showed IC50 values of 0.15?nM against T. congolense and 1.3?nM against T. vivax, and demonstrated 100% efficacy with a single dose of 10?mg/kg against both T. congolense and T. vivax in mouse models of infection (IP dosing) and in the target animal, cattle, dosed intramuscularly. AN11736 has been advanced to early development studies. 相似文献
136.
137.
Maltodextrin stimulates growth of Bacillus cereus and synthesis of diarrheal enterotoxin in infant milk formulae.
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One hundred reconstituted milk-based infant formulae (IMF) representative of 10 leading brands available in many European Economic Community countries were examined for Bacillus cereus and for the presence of diarrheal enterotoxin. Sixty-three reconstituted IMF supported growth of the organism after 14 h at 25 degrees C, and in 4 of these, which contained maltodextrin, enterotoxin was detected. Reconstituted IMF (and basal synthetic media) supplemented with > or = 0.1% maltodextrin supported both growth of B. cereus and diarrheal toxin production when incubated for 14 h or more at 25 degrees C. 相似文献
138.
Rowan A. Grayling Kathryn A. Bailey John N. Reeve 《Extremophiles : life under extreme conditions》1997,1(2):79-88
The DNA-binding and nuclease-protection properties of the HMf histones from the hyperthermophilic archaeon Methanothermus fervidus have been shown to be consistent with the formation of nucleosome-like structures (NLS). These proteins bind to DNA molecules
as short as 20 bp and form complexes that protect DNA fragments from micrococcal nuclease (MNase) digestion that are 30 bp,
∼ 60 bp and multiples of ∼ 60 bp in length. The sequences of 49 of the ∼ 60-bp DNA fragments protected from MNase digestion
by HMfA have been determined and their intrinsic curvatures calculated. A circular permutation gel mobility-shift assay was
used to determine directly the curvatures for five of these sequences. HMfA bound to intrinsically curved and noncurved DNAs,
but exhibited a slight preference for the model curved DNA in binding competitions with a model noncurved DNA. The results
obtained are consistent with the concept that the archaeal NLS is analogous, and possibly homologous, to the central core
of the eukaryal nucleosome formed by a histone (H3 + H4)2 tetramer.
Received: August 11, 1996 / Accepted: November 12, 1996 相似文献
139.
The nature of the interaction between drought and elevated CO2 partial pressure (pCa) is critically important for the effects of global change on crops. Some crop models assume that the relative responses of transpiration and photosynthesis to soil water deficit are unaltered by elevated pCa, while others predict decreased sensitivity to drought at elevated pCa. These assumptions were tested by measuring canopy photosynthesis and transpiration in spring wheat (cv. Minaret) stands grown in boxes with 100 L rooting volume. Plants were grown under controlled environments with constant light (300 µmol m?2 s?1) at ambient (36 Pa) or elevated (68 Pa) pCa and were well watered throughout growth or had a controlled decline in soil water starting at ear emergence. Drought decreased final aboveground biomass (?15%) and grain yield (?19%) while elevated pCa increased biomass (+24%) and grain yield (+29%) and there was no significant interaction. Elevated pCa increased canopy photosynthesis by 15% on average for both water regimes and increased dark respiration per unit ground area in well‐watered plants, but not drought‐grown ones. Canopy transpiration and photosynthesis were decreased in drought‐grown plants relative to well‐watered plants after about 20–25 days from the start of the drought. Elevated pCa decreased transpiration only slightly during drought, but canopy photosynthesis continued to be stimulated so that net growth per unit water transpired increased by 21%. The effect of drought on canopy photosynthesis was not the consequence of a loss of photosynthetic capacity initially, as photosynthesis continued to be stimulated proportionately by a fixed increase in irradiance. Drought began to decrease canopy transpiration below a relative plant‐available soil water content of 0.6 and canopy photosynthesis and growth below 0.4. The shape of these responses were unaffected by pCa, supporting the simple assumption used in some models that they are independent of pCa. 相似文献
140.
Corals of the Montastraea annularis complex host several different dinoflagellates in the genus Symbiodinium. Here we address two questions arising from our previous studies of these associations on an offshore reef. First, do the same taxa and patterns of association (Symbiodinium A and B found in higher irradiance habitats than Symbiodinium C) occur on an inshore reef? Second, does M. franksi at the limits of its depth range host only Symbiodinium C, as it does at intermediate depths? In both surveys, a new Symbiodinium taxon and different patterns of distribution (assayed by analyses of small ribosomal subunit RNA genes [srDNA]) were observed. Inshore, a taxon we name Symbiodinium E predominated in higher irradiance habitats in M. franksi and its two sibling species; the only other zooxanthella observed was Symbiodinium C. Offshore, M. franksi mainly hosted Symbiodinium C, but hosted Symbiodinium A, B, C, and E in shallow water and Symbiodinium E and C in very deep water. Symbiodinium E may be stress-tolerant. Observed srDNA heterogeneity within samples of Symbiodinium B, C, and E is interpreted as variation across copies within this multigene family. Experimental bleaching of Symbiodinium C supported this interpretation. Thus sequences from natural samples should be interpreted cautiously. 相似文献