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排序方式: 共有310条查询结果,搜索用时 15 毫秒
1.
Cytomegalovirus infection of the colon is a late and severe complication in human immunodeficiency virus patients. Despite availability of medical treatment, occasional life-saving emergency surgery must be performed. The controversial surgical aspects of treatment are discussed based upon an unusual case of aseptic generalized peritonitis without perforation. The feasibility and value of limited resection are emphasized. 相似文献
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Marius Sebastian Secula Igor Cretescu Benoit Cagnon Liliana Rozemarie Manea Corneliu Sergiu Stan Iuliana Gabriela Breaban 《Materials》2013,6(7):2723-2746
The aim of this study was to determine the effects of main factors and interactions on the color removal performance from dye solutions using the electrocoagulation process enhanced by adsorption on Granular Activated Carbon (GAC). In this study, a mathematical approach was conducted using a two-level fractional factorial design (FFD) for a given dye solution. Three textile dyes: Acid Blue 74, Basic Red 1, and Reactive Black 5 were used. Experimental factors used and their respective levels were: current density (2.73 or 27.32 A/m2), initial pH of aqueous dye solution (3 or 9), electrocoagulation time (20 or 180 min), GAC dose (0.1 or 0.5 g/L), support electrolyte (2 or 50 mM), initial dye concentration (0.05 or 0.25 g/L) and current type (Direct Current—DC or Alternative Pulsed Current—APC). GAC-enhanced electrocoagulation performance was analyzed statistically in terms of removal efficiency, electrical energy, and electrode material consumptions, using modeling polynomial equations. The statistical significance of GAC dose level on the performance of GAC enhanced electrocoagulation and the experimental conditions that favor the process operation of electrocoagulation in APC regime were determined. The local optimal experimental conditions were established using a multi-objective desirability function method. 相似文献
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Alexandru Hanganu Stanislav A. Groppa Günther Deuschl Hartwig Siebner Friederike Moeller Michael Siniatchkin Ulrich Stephani Sergiu Groppa 《Brain topography》2015,28(5):702-709
Photoparoxysmal response (PPR) is an EEG trait of spike and spike-wave discharges in response to photic stimulation that is closely linked to idiopathic generalized epilepsy (IGE). In our previous studies we showed that PPR is associated with functional alterations in the occipital and frontal cortices. The aim of the present study was to determine structural changes associated with PPR. For this purpose we analysed the cortical thickness as derived from T1 MRI images in PPR-positive-subjects (n = 12; 15.5 ± 8.6 years; 4 males), PPR-positive-IGE-patients (n = 12; 14.9 ± 2.7 years; 4 males) and compared these groups with a group of PPR-negative-healthy-controls (HC, n = 17; 15.3 ± 3.6 years; 6 males). Our results revealed an increase of cortical thickness in the occipital, frontal and parietal cortices bilaterally in PPR-positive-subjects in comparison to HC. Moreover PPR-positive-subjects presented a significant decrease of cortical thickness in the temporal cortex in the same group contrast. IGE patients exhibited lower cortical thickness in the temporal lobe bilaterally and in the right paracentral region in comparison to PPR-positive-subjects. Our study demonstrates structural changes in the occipital lobe, frontoparietal regions and temporal lobe, which also show functional changes associated with PPR. Patients with epilepsy present changes in the temporal lobe and supplementary motor area. 相似文献
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The synthesis of three novel tetracyclosiloxane monomers modified either with a nitroaniline (NA) or with a Disperse Red 1 (DR1) push–pull group and their ring opening polymerization reaction in the presence of tetramethylammonium hydroxide are presented. The prepared monomers and polymers were characterized by different spectral methods and gel permeation chromatography. For the crystalline monomers, the structures were further proven by single crystal X-ray diffraction. Dynamic scanning calorimetry shows that the polymers that carry NA groups have a glass transition temperature (Tg) well below room temperature (RT), while the one that carries DR1 groups melts at 55 °C. The transition temperatures have a strong effect on permittivity as indicated by broadband impedance spectroscopy measurements conducted at different temperatures and frequencies. The polymers modified with NA groups have a high permittivity (maximum value of 17.3) at RT, suggesting the polar groups to be mobile and orientation polarization to be effective. However, the polar groups of the polymer modified with DR1 are frozen and thus cannot contribute to the permittivity via orientation polarization. Consequently, the permittivity is only 8.8 at RT, but increases to 22 above the melting temperature, where the dipoles are mobile. Because of the high dielectric permittivity and rather low Tg, the polymers modified with NA are attractive as active dielectric materials in actuators, capacitors, and stretchable electronics, whereas the polymer modified with DR1 may be of interest in nonlinear optical devices.The synthesis of polysiloxanes modified with a nitroaniline or with a Disperse Red 1 push–pull group and their dielectric properties are reported. 相似文献
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Liliana Lucescu Alina Ghinet Sergiu Shova Romain Magnez Xavier Thuru Amaury Farce Benoît Rigo Dalila Belei Joëlle Dubois Elena Bîcu 《Archiv der Pharmazie》2019,352(5)
Unprecedented triazinyl‐isoxazoles were afforded via an effective cycloaddition reaction between nitrile oxides and the scarcely described 2‐ethynyl‐4,6‐dimethoxy‐1,3,5‐triazine as dipolarophile. The biological evaluation of the newly synthesized compounds showed that the inhibition of human farnesyltransferase by zinc complexation could be improved with triazine‐isoxazole moieties. The replacement of the isoxazole unit by a pyrrolidin‐2‐one was detrimental to the inhibitory activity while the pyrrolidin‐2‐thione derivatives conserved the biological potential. The potential of selected compounds to disrupt protein farnesylation in Chinese hamster ovary (CHO) cells transfected with pEGFP‐CAAX was also evaluated. 相似文献
9.
Hatice Kumru Enric Portell Marti Marti Sergiu Albu Josep M Tormos Joan Vidal Josep Valls-Sole 《Clinical neurophysiology》2013,124(7):1431-1438
ObjectiveParalytic poliomyelitis (pPM) is clinically suspected in individuals experiencing a non-progressive syndrome of flaccid paralysis and atrophy as a sequel of an acute infection. Despite normal sensory perception, patients with pPM complain of pain more than matched siblings. Here, we studied the characteristics of evoked pain in a cohort of pPM patients using contact heat evoked potentials and psychophysical tests.MethodsFifteen patients with pPM and 15 controls were studied. Inclusion criteria were unilateral or asymmetric involvement of lower extremities. Mechanical, warm and heat pain perception thresholds and evoked pain were measured in both thighs. Contact heat evoked potentials were recorded from the vertex.ResultsMechanical and heat pain thresholds were significantly lower in the affected than in the less-affected leg or in the legs of controls. Evoked pain ratings were significantly higher in the affected leg than in either the less-affected leg or in controls. Evoked potentials were significantly higher in the affected than in the less-affected leg.ConclusionPatients with pPM have mechanical and thermal hyperalgesia, which suggests abnormalities in processing of somatosensory inputs in these patients.SignificanceThis phenomenon should be taken into account in the routine clinical evaluation and management of pPM patients. 相似文献
10.
Sergiu Groppa Muthuraman Muthuraman Birte Otto Günther Deuschl Hartwig R. Siebner Jan Raethjen 《Brain stimulation》2013,6(2):138-146
BackgroundTranscranial magnetic stimulation (TMS) can modulate transiently the physiological brain oscillations, e.g. the alpha rhythm. It has been hypothesized that this effect is not limited to the stimulated region but involves subcortical and distant cortical areas.MethodsWe applied single pulse TMS to the primary motor cortex (M1) of healthy subjects to interfere the cortical oscillatory activity recorded by simultaneous EEG and calculated the cortico-cortical coherence and power in the alpha and beta band. To study the structural substrate of the functional connectivity we performed diffusion tensor imaging and fractional anisotropy analysis (FA). To capture the pathways involved we applied probabilistic tractography to reconstruct the entire network.ResultsSuprathreshold TMS of M1 induced a consistent enhancement of interhemispheric cortico-cortical alpha band coherence that lasted ca. 175 ms. after the pulse has been applied. The changes were confined to the interhemispheric central EEG electrodes (i.e. C3-C4). There were no consistent changes in the beta band. Power analysis revealed a longer lasting increase in the beta band after TMS pulses. A cluster in the contralateral thalamus showed a linear relationship between regional FA and TMS induced change in alpha band coherence. Probabilistic tractography presents the transcallosal and the contralateral thalamocortical pathways as essential for the observed oscillatory synchronisation.ConclusionTMS induces an enhancement of oscillatory interaction between corresponding central regions of both hemispheres in the alpha band. The contralateral thalamus, transcallosal fibres and the contralateral thalamocortical pathways may constitute critical brain structures mediating the TMS induced change in oscillatory coupling. 相似文献