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1.
Gareth AD Hardy Nesrina Imami Mark R Nelson Ann K Sullivan Ron Moss Marlén MI Aasa-Chapman Brian Gazzard Frances M Gotch 《Journal of immune based therapies and vaccines》2007,5(1):6-12
Background
Fully functional HIV-1-specific CD8 and CD4 effector T-cell responses are vital to the containment of viral activity and disease progression. These responses are lacking in HIV-1-infected patients with progressive disease. We attempted to augment fully functional HIV-1-specific CD8 and CD4 effector T-cell responses in patients with advanced chronic HIV-1 infection. 相似文献2.
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We have directly time resolved the lattice motions associated with the formation of the self-trapped exciton in the quasi-one-dimensional system [Pt(en)(2)] [Pt(en)2Br2];(PF6)(4) ( en = ethylene-diamine, C2H8N2), using femtosecond impulsive excitation techniques. A strongly damped, low-frequency wave packet modulation at approximately 110 cm(-1) accompanies the formation of the self-trapped exciton on a approximately 200 fs time scale following excitation of the intervalence charge-transfer transition. Coherent oscillations at the ground state vibrational frequency and its harmonics are also detected. 相似文献
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This paper gives one-term componentwise asymptotics for theM and spectral matrices of a self-adjoint realisation of aneven-order ordinary differential expression. The underlyinginterval is assumed to have at least one regular endpoint, andthe boundary conditions are supposed to be separated. Furthermore,the weight function and the reciprocal of the highest-ordercoefficient are supposed to be of regular variation at the regularendpoint, in the sense of Bingham, Goldie and Teugels. 1991Mathematics Subject Classification: 34B24, 34E05. 相似文献
7.
Phycotoxins produced by various species of toxigenic microalgae occurring in the plankton are a global threat to the security
of seafood resources and the health of humans and coastal marine ecosystems. This has necessitated the development and application
of advanced methods in liquid chromatography coupled to mass spectrometry (LC-MS) for monitoring of these compounds, particularly
in plankton and shellfish. Most such chemical analyses are conducted in land-based laboratories on stored samples, and thus
much information on the near real-time biogeographical distribution and dynamics of phycotoxins in the plankton is unavailable.
To resolve this problem, we conducted ship-board analysis of a broad spectrum of phycotoxins collected directly from the water
column on an oceanographic cruise along the North Sea coast of Scotland, Norway, and Denmark. We equipped the ship with a
triple-quadrupole linear ion-trap hybrid LC-MS-MS system for detection and quantitative analysis of toxins, such as domoic
acid, gymnodimine, spirolides, dinophysistoxins, okadaic acid, pectenotoxins, yessotoxins, and azaspiracids (AZAs). We focused
particular attention on the detection of AZAs, a group of potent nitrogenous polyether toxins, because the culprit species
associated with the occurrence of these toxins in shellfish has been controversial. Marine toxins were analyzed directly from
size-fractionated plankton net tows (20 μm mesh size) and Niskin bottle samples from discrete depths, after rapid methanolic
extraction but without any further clean-up. Almost all expected phycotoxins were detected in North Sea plankton samples,
with domoic acid and 20-methylspirolide G being most abundant. Although AZA was the least abundant of these toxins, the high
sensitivity of the LC-MS-MS enabled detailed quantification, indicating that the highest amounts of AZA-1 were present in
the southern Skagerrak in the 3–20 μm size-fraction. The direct on-board toxin measurements enabled isolation of plankton
from stations with high AZA-1 levels and from the most suspicious size-fraction, i.e. most likely to contain the AZA-producer.
A large number (>100) of crude cultures were established by serial dilution and later screened for the presence of AZAs after
several weeks growth. From one crude culture containing AZA, a small dinoflagellate was subsequently isolated and brought
into pure culture. We have thus proved that even sophisticated mass spectrometers can be operated in ship laboratories without
any limitation caused by vibrations of the ship’s engine or by wave movement during heavy seas at wind forces up to nine Beaufort.
On-board LC–MS–MS is a valuable method for near real-time analysis of phycotoxins in plankton for studies on bloom dynamics
and the fate of toxins in the food web, and for characterization and isolation of putatively toxigenic organisms. 相似文献
8.
Weihong Lin Ejiofor AD EzekweJr Zhen Zhao Emily R Liman Diego Restrepo 《BMC neuroscience》2008,9(1):114
Background
The main olfactory epithelium (MOE) in the nasal cavity detects a variety of air borne molecules that provide information regarding the presence of food, predators and other relevant social and environmental factors. Within the epithelium are ciliated sensory neurons, supporting cells, basal cells and microvillous cells, each of which is distinct in morphology and function. Arguably, the least understood, are the microvillous cells, a population of cells that are small in number and whose function is not known. We previously found that in a mouse strain in which the TRPM5 promoter drives expression of the green fluorescent protein (GFP), a population of ciliated olfactory sensory neurons (OSNs), as well as a population of cells displaying microvilli-like structures is labeled. Here we examined the morphology and immunocytochemical properties of these microvillous-like cells using immunocytochemical methods. 相似文献9.
MacKinnon SL Cembella AD Burton IW Lewis N LeBlanc P Walter JA 《The Journal of organic chemistry》2006,71(23):8724-8731
Biosynthetic origins of the cyclic imine toxin 13-desmethyl spirolide C were determined by supplementing cultures of the toxigenic dinoflagellate Alexandrium ostenfeldii with stable isotope-labeled precursors [1,2-13C2]acetate, [1-13C]acetate, [2-13CD3]acetate, and [1,2-13C2,15N]glycine and measuring the incorporation patterns by 13C NMR spectroscopy. Despite partial scrambling of the acetate labels, the results show that most carbons of the macrocycle are polyketide-derived and that glycine is incorporated as an intact unit into the cyclic imine moiety. This work represents the first conclusive evidence that such cyclic imine toxins are polyketides and provides support for biosynthetic pathways previously defined for other polyether dinoflagellate toxins. 相似文献
10.
Marijke WA de Backer Carlos P Fitzsimons Maike AD Brans Mieneke CM Luijendijk Keith M Garner Erno Vreugdenhil Roger AH Adan 《BMC neuroscience》2010,11(1):81