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A 59-year-old hypertensive male, 1 year after uncomplicatedmitral annuloplasty for regurgitation with MAZE procedure, witha history of chronic obstructive pulmonary disease and repeatedpulmonary 相似文献
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In thePseudemys turtle retina five functionally distinct, electrically coupled networks of horizontal cells distribute signals in the outer plexiform layer. These networks differ significantly in their architecture, as determined by intracellular labeling with Neurobiotin after physiological recording and identification. The density of H1 horizontal cells is highest, ranging around 1800 cells/mm2 at approximately 2.3 mm eccentricity. H1 horizontal cell somata are connected via 6–10 thin, short dendrites. The H1 horizontal cell axon terminal network is composed of thick axon terminals, forming a three-dimensional, sheath-like structure. Networks of coupled H2 and H3 horizontal cells have cell densities of around 210 cells/mm2 and 350 cells/mm2 respectively, at the same eccentricity of 2.3 mm. Cell bodies are connected with 6–12 long, thin dendrites. Here we report for the first time H4 horizontal cell networks. Cell density is approximately 970 cells/mm2 at 2 mm eccentricity, and cell bodies are connected with 6–10 thin, short dendrites. General properties of passive voltage spread were compared for three of these horizontal cell networks using NeuronC. Realistic network architectures were obtained by digitizing the intracellularly labeled networks, respectively. One network obtained from coupled H1 horizontal cell bodies, one from coupled H1 horizontal cell axon terminals, and one from H2 horizontal cells were simulated. These three realistic networks were compared with an artificial, electrically coupled regular triangular network. Passive signal spread in these networks strongly depended on the exact network architecture using otherwise identical parameters. Changes in coupling strength affected signal spread in these networks differently. As in the experimental situation, changes in synaptic conductance influenced signal spread. Some principal effects of extensively coupled horizontal cells on photoreceptor signal processing were simulated with one type of photoreceptor connected by telodendria, synapsing onto an underlying triangular network and receiving feedback synapses. Under certain conditions, spatial information is coded in single photoreceptors. This was also the case in the experimental situation. In the simulation, spatial filter adjustment for optimal spatial coding in photoreceptors can be achieved by changing coupling strength in the horizontal cell network. 相似文献
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Peter Schnider MD Joachim Maly PhD Josef Grünberger PhD Susanne Aull MD Karl Zeiler MD Peter Wessely MD 《Headache》1995,35(5):269-272
A considerable proportion of headache patients fulfill the criteria of "drug abuse" (definition according to the International Headache Society [IHS] criteria). These patients exhibit markedly reduced vigilance and continuous performance, as shown by the results of critical flicker frequency (CFF) analysis.
The present study deals with the question whether this impairment of vigilance and continuous performance is reversible. Forty-eight headache patients with drug abuse were investigated three times by means of CFF analysis: immediately before (A), immediately after (B), and 3 weeks after having finished (C) inpatient drug withdrawal.
Immediately after withdrawal, a significant decrease of headache intensity was observed. The CFF values, however, remained unchanged at a depressed level, probably due to withdrawal medication and the initial sedative side effects of thymoleptic agents (given as prophylaxis).
Three weeks after withdrawal, however, the CFF values were significantly improved, and were now within a range not far from the normal values known from a healthy general population. Thus, even after many years of drug abuse, headache patients have a good chance to improve their vigilance and continuous performance and to reach normal or close to normal levels. 相似文献
The present study deals with the question whether this impairment of vigilance and continuous performance is reversible. Forty-eight headache patients with drug abuse were investigated three times by means of CFF analysis: immediately before (A), immediately after (B), and 3 weeks after having finished (C) inpatient drug withdrawal.
Immediately after withdrawal, a significant decrease of headache intensity was observed. The CFF values, however, remained unchanged at a depressed level, probably due to withdrawal medication and the initial sedative side effects of thymoleptic agents (given as prophylaxis).
Three weeks after withdrawal, however, the CFF values were significantly improved, and were now within a range not far from the normal values known from a healthy general population. Thus, even after many years of drug abuse, headache patients have a good chance to improve their vigilance and continuous performance and to reach normal or close to normal levels. 相似文献
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Andreas Ritsch Christoph Ebenbichler Elisabeth Naschberger Wilfried Schgoer Ursula Stanzl Hermann Dietrich Peter C Heinrich Kazunori Saito Josef R Patsch 《Clinical chemistry and laboratory medicine》2004,42(3):247-255
Cholesteryl ester transfer protein (CETP) greatly affects the metabolism of all lipoprotein classes including low-density lipoprotein (LDL) and high-density lipoprotein (HDL), both known to constitute powerful risk factors for coronary artery disease (CAD). We now report the successful first cloning and characterization of single-chain antibody fragments specific for CETP. A recombinant phage display library was generated using spleen mRNA isolated from BALB/c mice that had been immunized with highly purified CETP. Screening of the library yielded two single-chain antibody fragments with high affinity for CETP, termed 1CL8 and 1CL10, displaying respective KD values of 4.36 x 10(-9) M and 4.64 x 10(-9) M as determined by affinity sensor technology. Amino acid sequence comparison indicated the complementarity-determining regions of the respective heavy chains to be responsible for CETP high affinity binding. Fragment 1CL8 was successfully employed in clinical chemical quantification systems that uncovered an association in humans between plasma CETP concentration and total body fat mass (r=0.50, p<0.002). Because of the demonstrated superb CETP capturing capacity, combined with high binding affinity to CETP, ready access and unlimited supply, 1CL8 and 1CL10 are expected to prove powerful tools for studies on the role of CETP in atherogenesis. 相似文献
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Claudia St?llberger Josef Finsterer Birke Schneider 《Journal of the American College of Cardiology》2006,47(7):1500; author reply 1500-1500; author reply 1501
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T. Hammen F. Kerling M. Schwarz A. Stadlbauer O. Ganslandt B. Keck B. Tomandl A. Dörfler H. Stefan 《European journal of neurology》2006,13(5):482-490
Up to 30% of patients with temporal lobe epilepsy (TLE) remain without remarkable changes in MRI. In this study we investigated the role of (1)H-MR spectroscopy ((1)H-MRS) in lateralizing the affected hemisphere in the mentioned patient group. Twenty-two consecutive patients diagnosed with TLE were investigated by high resolution MRI and (1)H-MRS. We examined the incidence and diagnostic accuracy of temporal metabolite alterations determined by Linear Combination of Model Spectra (L C Model) via water reference. Metabolite values of each hemisphere of TLE patients were compared with healthy controls. Results of metabolite alterations were related to intensive video EEG focus localization. Reduction of N-acetylaspartate + N-acetylaspartyl-glutamate (tNAA) in the affected hemisphere revealed identification in six of nine patients (66%) with unilateral TLE. Group comparison revealed a significant reduction of tNAA (6.1+/-0.8*) in the involved temporal lobe compared with controls (6.67+/-0.4*, P=0.026). Choline levels were significantly increased in the affected hemisphere (1.42+/-0.17*) compared with healthy controls (1.22+/-0.17*, P=0.035). The results of our study show that (1)H-MRS is able to identify the affected hemisphere of MRI negative TLE patients and can be used as an additive tool in multimodal focus localization. 相似文献