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排序方式: 共有1318条查询结果,搜索用时 15 毫秒
131.
Eriksson A Bergquist J Edwards K Hagfeldt A Malmström D Hernández VA 《Analytical chemistry》2011,83(3):761-766
A simple method for on-target enrichment and subsequent separation and analysis of phosphorylated peptides is presented. The tryptic digest of a phosphorylated protein, in this case β-casein, is loaded onto a spot on a thin stripe made of mesoporous TiO(2) sintered onto a conductive glass surface. After washing with a salicylic buffer in order to remove the nonphosphorylated peptides, the stripe is placed in an elution chamber containing a phosphate solution. In a way analogous to thin layer chromatography (TLC), the phosphate solution acts as an eluent, clearly separating multi- and monophosphorylated peptides. By performing matrix-assisted laser desorption-ionization mass spectrometry (MALDI-MS) along the stripe, the detection of all phosphorylated peptides present in the digest is facilitated, as they are isolated from each other. The method was also tested on commercial drinking milk, achieving successful separation between multi- and monophosphorylated peptides, as well as a detection limit in the femtomole range. As the enrichment, separation, and analysis take place in the same substrate, sample handling and risk of contamination and sample loss is minimized. The results obtained suggest that the method, once optimized, may successfully provide a complete phosphoproteome. 相似文献
132.
G Rosenblat N Perelman E Katzir S Gal-Or A Jonas ME Nimni N Sorgente I Neeman 《Canadian Metallurgical Quarterly》1998,37(3-4):303-311
Acylated derivatives of ascorbic acid were found to be active in a number of biochemical and physiological processes. In the present study we investigated the effects of 6-O-palmitoyl ascorbate on collagen synthesis by cultured foreskin human fibroblasts. Our observations indicate a marked stimulatory effect on collagen synthesis by 6-O-palmitoyl ascorbate in the concentration range of 5-20 microM, while the synthesis stimulated by ascorbic acid was maximal at concentrations of 20-100 microM. Cells treated with 10 microM palmitoyl ascorbate for 36 h exhibited a production of collagen threefold greater than those in the presence of 10 microM ascorbic acid, and it was about the same as in cells treated with 100 microM ascorbic acid. By 48 h differences were not significant. Acylated ascorbate impaired vitality of the treated fibroblasts at concentrations exceeding 20 microM in media supplemented with 0.5% FCS. However, most of the cytotoxic effect was neutralized by FCS at a concentration of 10%. The resistance of acylated ascorbate against oxidative degradation as well as the role of free radicals in the modulation of collagen synthesis by ascorbic acid and by its derivatives is discussed. 相似文献
133.
JI Hudson SL McElroy NC Raymond S Crow PE Keck WP Carter JE Mitchell SM Strakowski HG Pope BS Coleman JM Jonas 《Canadian Metallurgical Quarterly》1998,155(12):1756-1762
OBJECTIVE: The purpose of this study was to assess the efficacy of fluvoxamine in the treatment of binge-eating disorder. Binge-eating disorder is a newly described eating disorder characterized by recurrent episodes of binge eating but without purging behaviors. Uncontrolled reports have suggested that serotonin selective reuptake inhibitors (SSRIs) may be effective in treating this disorder. METHOD: Eighty-five outpatients with a DSM-IV diagnosis of binge-eating disorder were randomly assigned to receive either fluvoxamine (N=42) or placebo (N=43) in a 9-week, parallel-group, double-blind, flexible dose (50-300 mg) study at three centers. The primary outcome measures were frequency of binge eating, expressed as log ([binges/week]+1), and Clinical Global Impression (CGI) scale ratings. Secondary measures included the level of response (based on the percentage change in frequency of binges), body mass index, and Hamilton Rating Scale for Depression score. Except for the level of response, the outcome measures were analyzed by random regression methods; the treatment-by-time interaction was the measure of treatment effect. RESULTS: Compared with placebo, fluvoxamine was associated with a significantly greater rate of reduction in the frequency of binges, rate of reduction in CGI severity scores, rate of increase in CGI improvement scores, level of response for patients who completed the 9-week study, and rate of reduction in body mass index. There was no significant difference between placebo and fluvoxamine groups in the rate of decrease in Hamilton depression scale scores. A significantly greater proportion of patients receiving fluvoxamine than those receiving placebo discontinued treatment because of an adverse medical event. CONCLUSIONS: In this placebo-controlled trial, fluvoxamine was found to be effective according to most outcome measures in the acute treatment of binge-eating disorder. 相似文献
134.
A highly specific anti-glutamate monoclonal antibody, mAb2D7, was used together with light and electron microscopy to elucidate the role played by the amino acid glutamate in the projection from the olfactory bulb to the piriform cortex in the rat. By light microscopy, glutamate-like immunoreactivity was observed in neuronal cell bodies and in the neuropil of the piriform cortex. Double labelling experiments which involved injections of wheat germ agglutinin-horse--radish peroxidase into the olfactory bulb and a post-embedding immunogold method for electron microscopy revealed anterogradely labelled terminals making asymmetric synaptic contacts on dendrites in the piriform cortex which contained high levels of glutamate as assessed by quantification. These results further support a role for glutamate as a neurotransmitter in the efferent pathway of the rat olfactory bulb. 相似文献
135.
Jonas Chapuis Alexander Schramm Ion Pappas Wock Hallermann Katja Schwenzer-Zimmerer Frank Langlotz Marco Caversaccio 《IEEE transactions on information technology in biomedicine》2007,11(3):274-287
A new system for computer-aided corrective surgery of the jaws has been developed and introduced clinically. It combines three-dimensional (3-D) surgical planning with conventional dental occlusion planning. The developed software allows simulating the surgical correction on virtual 3-D models of the facial skeleton generated from computed tomography (CT) scans. Surgery planning and simulation include dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and segment repositioning. By coupling the software with a tracking system and with the help of a special registration procedure, we are able to acquire dental occlusion plans from plaster model mounts. Upon completion of the surgical plan, the setup is used to manufacture positioning splints for intraoperative guidance. The system provides further intraoperative assistance with the help of a display showing jaw positions and 3-D positioning guides updated in real time during the surgical procedure. The proposed approach offers the advantages of 3-D visualization and tracking technology without sacrificing long-proven cast-based techniques for dental occlusion evaluation. The system has been applied on one patient. Throughout this procedure, we have experienced improved assessment of pathology, increased precision, and augmented control. 相似文献
136.
Jonas
rtegren Philippe Busson Mikael Lindgren David S. Hermann Per-Otto Arntzen Fredrik Sahlen Mikael Trollss Ulf W. Gedde Anders Hult Lechezar Komitov Sven T. Lagerwall Per Rudquist Bengt Stebler 《Optical Materials》1998,9(1-4):220-225
Second harmonic generation in novel pyroelectric liquid crystal polymers (PLCP) made from a series binary mixtures, was studied using 1100 nm as the fundamental wavelength. The PLCPs were prepared by photo-polymerization of binary mixtures of two monomers which exhibit a smectic C* phase, A2c (4″-(R)-(−)-2-[(10-acrylo-yloxy)decyl]oxy-3-nitrophenyl 4-{4′-[(11-acryloyloxy)-undecyloxy]phenyl}benzoate) and Alb (4″-((R)-(+)-2-octyloxy)-3″-nitrophenyl 4-(4′-(11-acryloyloxy)undecyloxy)-phenyl)-benzoate). The highest d16 and d23 coefficients were found to be in the range 0.65–0.8 pm/V, and differed depending on the detailed preparation of the sample. All cases of polymers formed from the chiral smectic C* phase showed an SHG-signal with no external field present, indicating that polar order became fixed. The SHG-signal was found to increase with the tilt angle of the FLC molecules. 相似文献
137.
In normal eyes, the retinal nerve fiber layer (RNFL) is usually best visible in the inferior temporal part of the fundus, followed by the superior temporal region, the nasal superior region and the nasal inferior region. This distribution correlates with the configuration of the neuroretinal rim, the diameter of the retinal arterioles, the location of the foveola, and the lamina cribrosa morphology. With increasing age, the RNFL visibility decreases diffusely without preferring special fundus regions and without the development of localized defects. With all optic nerve diseases, the visibility of the RNFL is decreased in addition to the age-related loss, in a diffuse and/or a localized manner. The localized defects are wedge-shaped and not spindle-like defects, running toward or touching the optic disk border. Typically occurring in about 20% of all glaucoma eyes, they can be found also in other ocular diseases, such as optic disk drusen, toxoplasmotic retinochoroidal scars, longstanding papilledema or optic neuritis due to multiple sclerosis. Since they are not present in normal eyes, they almost always signify an abnormality. RNFL evaluation is especially helpful for early glaucoma diagnosis and in glaucoma eyes with small optic disks. In advanced optic nerve atrophy, other examination techniques, such as perimetry, may be more helpful for following optic nerve damage. Considering its great importance in the assessment of optic nerve anomalies and diseases and taking into account the feasibility of its ophthalmoscopic evaluation using green light, the retinal nerve fiber layer should be examined during any routine ophthalmoscopy. 相似文献
138.
D Shum-Tim M Nagashima T Shinoka J Bucerius G Nollert HG Lidov A du Plessis PC Laussen RA Jonas 《Canadian Metallurgical Quarterly》1998,116(5):780-792
BACKGROUND: Aggressive surface warming is a common practice in the pediatric intensive care unit. However, recent rodent data emphasize the protective effect of mild (2 degrees - 3 degrees C) hypothermia after cerebral ischemia. This study evaluates different temperature regulation strategies after deep hypothermic circulatory arrest with a survival piglet model. METHODS: Fifteen piglets were randomly assigned to 3 groups. All groups underwent 100 minutes of deep hypothermic circulatory arrest at 15 degrees C. Brain temperature was maintained at 34 degrees C for 24 hours after cardiopulmonary bypass in group I, 37 degrees C in group II, and 40 degrees C in group III. Neurobehavioral recovery was evaluated daily for 3 days after extubation by neurologic deficit score (0, normal; 500, brain death) and overall performance category (1, normal; 5, brain death). Histologic examination was assessed for hypoxic-ischemic injury (0, normal; 5, necrosis) in a blinded fashion. RESULTS: All results are expressed as mean +/- standard deviation. Recovery of neurologic deficit score (12.0 +/- 17.8, 47.0 +/- 49.95, 191.0 +/- 179.83; P = .05 for group I vs III), overall performance category (1.0 +/- 0.0, 1.4 +/- 0.6, 2.8 +/- 1.3; P < .05 for group I vs III), and histologic scores (0.0 +/- 0.0, 1.0 +/- 1.2, 2.8 +/- 1.8; P < .05 for group I vs III cortex) were significantly worse in hyperthermic group III. These findings were associated with a significantly lower cytochrome aa3 recovery determined by near-infrared spectroscopy in group III animals (P = .0041 for group I vs III). No animal recovered to baseline electroencephalographic value by 48 hours after deep hypothermic circulatory arrest. Recovery was significantly delayed in the hyperthermic group III animals, with a lower amplitude 14 hours after the operation, which gradually increased with time (P < .05 for group III vs groups I and II). CONCLUSIONS: Mild postischemic hyperthermia significantly exacerbates functional and structural neurologic injury after deep hypothermic circulatory arrest and should therefore be avoided. 相似文献
139.
A quasi-ARMAX modelling scheme is studied for the purpose of modelling and control of multi-variable ill-conditioned and nonlinear processes. A distillation column is used as a case-study. The modelling technique is in this paper extended for use in the multi-variable case. Also, the nonlinear directionality of the distillation column is analyzed and illustrated. The nonlinear MPC formulation with the quasi-ARMAX model used for prediction is studied for control of the distillation column at different operating regions. 相似文献
140.
The business model concept is becoming increasingly popular within IS, management and strategy literature. It is used within many fields of research, including both traditional strategy theory and in the emergent body of literature on e-business. However, the concept is often used independently from theory, meaning model components and their interrelations are relatively obscure. Nonetheless, we believe that the business model concept is useful in explaining the relation between IS and strategy. This paper offers an outline for a conceptual business model, and proposes that it should include customers and competitors, the offering, activities and organisation, resources and factor market interactions. The causal inter-relations and the longitudinal processes by which business models evolve should also be included. The model criticises yet draws on traditional strategy theory and on the literature that addresses business models directly. The business model is illustrated by an ERP implementation in a European multi-national company. 相似文献