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31.
32.
Virgil Percec Gabriela Zipp Gary Johansson Uwe Beginn Martin Mller 《Macromolecular chemistry and physics.》1997,198(2):265-277
Synthesis and characterization of methacrylate-monofunctionalized crown ether compounds based on derivatives of 2-hydroxymethyl-1,4,7,10,13-pentaoxacyclopentadecane and 4′-hydroxymethyl-1,4,7,10,13-pentaoxabenzocyclopentadecane is described. By differential scanning calorimetry (DSC) and thermooptical analysis (TOA) it is shown that the synthesized compounds and their sodium triflate complexes exhibit columnar mesophases. 相似文献
33.
L. Zller J. Scholz R. Stohwasser L. B. Giebel K. K. Sethi E. K. F. Bautz G. Darai 《Journal of medical virology》1989,27(3):231-237
Sera from patients with nephropathia epidemica (NE) or Korean hemorrhagic fever (KHF) were tested for specific antibody response to antigens of H?lln?s virus and Hantaan virus strain 76-118. A Vero E6 derived cell line persistently infected with H?lln?s virus strain B1, and Vero E6 cells freshly infected with Hantaan virus type strain 76-118 were used as antigens in the immunofluorescence assay (IFA) and the immunoblot. Blots were prepared from whole cell lysates. The convalescent-phase sera of NE patients tested in this study regularly revealed a marked reaction with a 52 kilodalton (Kd) protein of H?lln?s virus and a 50 Kd protein of Hantaan virus. A convalescent serum from a patient with Korean hemorrhagic fever and a rat antiserum against Hantaan virus could recognize the 50 Kd band of Hantaan virus but showed no apparent reactivity with the 52 Kd component of H?lln?s virus in the standard dilutions. Some sera could additionally identify minor bands in the 55 Kd and/or 67 Kd region of the blots. A one-way cross reactivity between Hantaan and H?lln?s viruses was also evident from the results of the immunofluorescence assays in that NE convalescent sera reacted with both viruses, whereas KHF convalescent or anti-Hantaan sera gave strongly positive results with Hantaan virus but only faint reaction with H?lln?s virus. 相似文献
34.
J. Scholz A. Rsen-Wolff J. Bugert H. Reisner M. I. White G. Darai R. Postlethwaite 《Journal of medical virology》1989,27(2):87-90
The molecular epidemiology of molluscum contagiosum virus (MCV) infections was investigated by restriction endonuclease analysis of the genomes of 222 separate isolates collected from 147 patients living in Germany (33 patients), Hong Kong (6 patients), and Scotland (108 patients). MCV type 1 (MCV-1) caused 96.6% of the infections, and MCV type 2 (MCV-2) caused 3.4%. However, isolates from four of the 142 MCV-1-infected patients and two of the five MCV-2-infected patients showed minor differences in their DNA restriction patterns because of the loss of a single or very few recognition sites for the enzymes used. No genome variations were detected amongst isolates collected from different sites or on several occasions from individual patients or from closely related patients. Southern blot hybridization revealed a high level of relatedness between MCV-1 and 2. No differences were seen in the appearance or anatomical localization of lesions caused by either virus type. In particular, there was no preferred genital localization for MCV-2 infections. 相似文献
35.
The authors investigated the influence of human body inhomogeneities such as the lungs, blood masses and the skeletal muscle layer on the electrical body surface potential and the magnetic field. The surface potentials and magnetic fields are calculated using a boundary element method. As a rule the blood masses have a large influence on both potential and magnetic field amplitude as well as on the potential and magnetic field map orientation, but the influence on the topology of the map is less in the electric case than in the magnetic case. The single-dipole reconstruction was applied to estimate the error caused by neglecting inner inhomogeneities in source localization. The neglect of lungs and blood masses results in a localization error of less than 1 cm in the electric case but more than 1 cm for deep sources at the posterior side of the heart in the magnetic case. The authors tried to assess the influence of the skeletal muscle layer by both an analytical two-layered anisotropic half-space model and the torso extension method. The skeletal muscle layer causes a smoothing effect on the electrical surface potential and to a lesser extent on the magnetic field, leading to an overestimation of the actual source depth of about 1-2 cm. In principle this can be reduced by taking data from all over the thoracic surface. The authors designed experiments for simultaneous measurement of body surface potential and extracorporeal magnetic field from the same subject. The evaluation of data from two patients showing Wolff-Parkinson-White syndrome has shown that localization results from electric potential data and magnetocardiographic data are consistent. 相似文献
36.
In this study the influence of special memory tasks, the effect of cues and the influence of the severity of the disease on the performance of short-term memory of patients suffering from Huntington's disease was examined. Stimulus material consisted of 30 nouns for reproduction and 20 nouns to be subsumed to 5 categories. Depending on experimental condition, assistance was given or withheld. 16 healthy subjects and 48 patients suffering from Huntington's disease took part in the study. Between these groups there was a significant effect of the factor "memory task." Furthermore, it could be demonstrated that the performance level decreases and differences between individuals increase with increasing severity of the disease. There was no significant effect of the factor "cues." 相似文献
37.
38.
Notfall + Rettungsmedizin - Das akute Koronarsyndrom ist der häufigste Grund für einen Rettungsdiensteinsatz in Deutschland. So resultieren in etwa 20–25 % aller Einsätze... 相似文献
39.
40.
MRI findings in Hirayama’s disease: flexion-induced cervical myelopathy or intrinsic motor neuron disease? 总被引:6,自引:0,他引:6
Schröder R Keller E Flacke S Schmidt S Pohl C Klockgether T Schlegel U 《Journal of neurology》1999,246(11):1069-1074
Hirayama’s disease is a benign juvenile form of focal amyotrophy affecting the upper limbs. Previous studies have suggested
that the disorder is a neck flexion induced cervical myelopathy. We report clinical and magnetic resonance imaging findings
in nine patients with Hirayama’s disease. Cervical imaging of seven patients revealed spinal cord changes consisting of focal
atrophy and foci of signal alterations. On neck flexion a forward movement and mild reduction in the anteroposterior diameter
of the lower cervical cord against the vertebral bodies was noted in affected individuals as well as in five normal controls.
In contrast to earlier reports, none of our patients showed complete obliteration of the posterior subarachnoid space. Measurement
of the anteroposterior spinal cord diameter in each vertebral segment (C4–C7) revealed no significant differences in the degree
of spinal cord flattening between the two groups. Furthermore, two of our patients had significant degenerative changes in
the cervical spine (disc herniation, retrospondylosis) contralateral to the clinically affected side. These degenerative changes
resulted in a marked cord compression on neck flexion but were not associated with ipsilateral clinical abnormalities or spinal
cord alterations. Our results argue against a flexion-induced cervical myelopathy and support the view that Hirayama’s disease
is an intrinsic motor neuron disease.
Received: 15 March 1999 Received in revised form: 25 May 1999 Accepted: 1 June 1999 相似文献