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31.
The investigation of a plant cell culture of RUTA CHALEPENSIS L. yielded three compounds: isorutarin, rutacridone, and rutarensin, a so far unknown ester of daphnoretin glucoside ("daphnorin"), as well as 3-hydroxy-3-methylglutaric acid. 相似文献
32.
Molecular characterisation of two mumps virus genotypes circulating during an epidemic in Lithuania from 1998 to 2000 总被引:3,自引:0,他引:3
Summary. An epidemic of mumps in Lithuania started in December 1998 and continued until May 2000. The total registered number of cases
was about 11.000 of a total of 3,7 million inhabitants in Lithuania (29,7 cases/10000). Virus- containing samples were collected
from 80 patients treated at the hospital of Kaunas from October 1999 until the end of the epidemic. Out of the 80 patients
with parotitis, meningitis was observed in 11 patients and orchitis in 22 of 69 male patients. Twenty-seven virus strains
were genotyped by nucleotide sequencing of the small hydrophobic (SH) protein gene, and the 57 amino acid sequences of the
gene were deduced. Twenty-five virus strains belonged to the C genotype and two were of the D genotype. By phylogenetic analysis
the virus strains causing meningitis grouped in a separate cluster, designated C1, within the C genotype. Another group of
ten of the 25 genotype C strains exhibited an amino acid triplet at amino acid positions 28 to 30 of the protein, consisting
of valine, alanine and serine, instead of the previously recognised valine, valine and serine combination of genotype C. The
amino acid alanine at position 29 was found in combination with the amino acid serine at position 48. This variant was designated
C2 and it was associated with parotitis. The amino acid alanine at position 29 and serine in position 48 of the C2 genotype
may constitute a marker of low neurovirulence compared to other genotype C strains.
Received July 9, 2001 Accepted October 23, 2001 相似文献
33.
Kainate receptors have been studied extensively in vitro , but how they might function physiologically remains unclear. We studied kainate receptor modulation of synaptic responses in the rat ventrobasal thalamus using the novel antagonist LY382884 and the agonist ATPA (selective for GluR5-containing kainate receptors) as tools. No evidence could be found for a direct contribution of kainate receptors to responses of thalamic relay cells to lemniscal (sensory) input in thalamic slices studied with the aid of intracellular and field potential recordings, using selective AMPA and NMDA receptor antagonists and LY382884. However, the GluR5 agonist ATPA reduced the IPSPs originating from the thalamic reticular nucleus. Extracellular single-neurone recordings in anaesthetised rats showed that excitatory responses evoked by physiological vibrissa afferent stimulation were reduced by LY382884 applied iontophoretically at the recording site. This action of the antagonist was occluded when GABA receptors were blocked, indicating that the reduction in excitatory sensory responses by LY382884 is due to an action on GABAergic inhibition arising from the thalamic reticular nucleus. Further experiments showed that these actions depended on whether inhibition was evoked during activation of the excitatory receptive field rather than when inhibition was evoked from a surround vibrissa. We suggest that GluR5 is located presynaptically on inhibitory GABAergic terminals of thalamic reticular nucleus neurones, and that it is normally activated by glutamate spillover from synapses between excitatory afferents and relay neurones during physiological stimulation. We propose that this GluR5-activated disinhibition has an important novel role in extracting sensory information from background noise. 相似文献
34.
Sven-Erik Larsson Hongming Cai P. Åke Öberg 《European journal of applied physiology》1993,66(6):483-488
Summary Microcirculation in the upper portion of the trapezius muscle was measured percutaneously by continuous laser-Doppler flowmetry (LDF) during two 10-min series of alternating 1-min periods of static contraction and rest determined electromyographically (EMG). Stepwise increased contraction was induced by keeping the arms straight and elevated at 30, 60, 90 and 135°, which was repeated with a 1-kg load carried in each hand. Thereafter, fatigue and recovery were recorded while the subject kept her arms straight and elevated at 45° carrying the 1-kg hand load as long as possible, followed by rest with arms hanging and no load. A group of 16 healthy women of different ages was studied. Signal processing was done on line using a 386 SX computer. The LDF- and root-mean-square (rms) EMG signals were normalized. Spectrum analyses of EMG mean power frequency (MPF) and median spectrum frequency were performed. The rms-EMG increased significantly with an increase in the calculated shoulder torque (r=0.75). Accumulated local fatigue was indicated by a decrease in MPF with increased shoulder angle and added load (r = –0.54). Blood flow increased with increased shoulder angle (r=0.82, with hand loadr=0.62) and with increased shoulder torque (r=0.72), and also showed a significant increase with increased EMG activity (r=0.74). The LDF showed a negative correlation to MPF (r= –0.67), with increased values when MPF was lowered. During the endurance test, a moderate increase of LDF occurred which reached its maximum during the 1st min of recovery. Then, a slow return to the base level was recorded. The ability to increase the flow in the microcirculation with increasing muscle load was not diminished with age. 相似文献
35.
Günther Vogel Heinz Krause Elisabeth Krämer 《Pflügers Archiv : European journal of physiology》1955,261(5):486-494
Ohne ZusammenfassungBenutzte Symbole und Abkürzungen NNR
Nebennierenrinde
- DOCA
Desoxycorticosteronacetat
-
K
i
intracelluläres Kalium (sinngemäß für Natrium)
-
K
a
extracelluläres Kalium (sinngemäß für Natrium)
-
Q
Ladung
-
E
m
Membranruhepotential
-
m
Zeitkonstante der Membran
-
R
m
Membranwiderstand
-
C
m
Membrankapazität 相似文献
36.
Volker Schmidt Susanne Schneider Julian Schlömer Maria-Elisabeth Krautwald-Junghanns Elvira Richter 《Avian pathology》2008,37(6):589-592
The present report describes a case of Mycobacterium tuberculosis infection in an African Grey parrot (Psittacus erithacus erithacus) kept as a pet bird. Diagnosis was confirmed by microbiologic and pathologic results, and indicated a human–avian transmission. Clinical signs included sublingual nodules resulting in anorexia and signs of osteolysis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation without intralesional acid-fast rods. M. tuberculosis was cultured from a pooled sample of sublingual and liver nodules, and was confirmed via polymerase chain reaction. Transmission between men and parrot was proved by spoligotyping pattern analysis. The absence of facial skin lesions and acid-fast rods within the tubercles is contrary to previous publications of tuberculosis in birds. This disease in a common pet bird species is of zoonotic importance, and those parrots with close contact to owners suffering from tuberculosis may serve as a potential reservoir for human infection. 相似文献
37.
Oxytocin-, vasopressin- and neurophysin-containing axons were visualized within the rat caudal medulla using the immunoperoxidase technique. The highest densities of axons and terminals were found in the nucleus tractus solitarius, nucleus dorsalis vagus, nucleus commissuralis, nucleus reticularis lateralis and within the marginal layer of the nucleus trigeminalis. In these areas, oxytocin fibres predominated markedly over vasopressin fibres. In a series of electrophysiological experiments, neurones in these and surrounding areas were predominantly depressed following the iontophoretic application of oxytocin. This depression was seen on both spontaneous and glutamate-evoked neuronal firing. 相似文献
38.
O M Ariyürek F Balkanci Ü Aydingöz M Önerci 《Surgical and radiologic anatomy : SRA》1996,18(2):137-139
Summary Anatomic variations are important in preendoscopic CT evaluation of the paranasal sinuses. In this study, we investigated whether the superior turbinate could become pneumatised like the middle turbinate, pneumatisation of which is well-known. Images of 52 patients who underwent CT examination prior to endoscopic sinus surgery and who had normally aerated posterior ethmoidal cells and an unobscured nasal cavity were retrospectively evaluated. The patients were 12–68 years old (median age, 35 years); 28 were women and 24 were men. Pneumatisation of the superior turbinates was graded in two groups as minimal or marked. Pneumatisation was evident in 25 patients (48%). 13 unilateral (25%), 8 bilateral (15%) pneumatisations were detected in the group graded as minimal, whereas 1 unilateral and 3 bilateral pneumatisations were present in the markedly (8%) pneumatised group of patients. Superior turbinates were seemingly aerated through the posterior ethmoid cells. The superior turbinates can be pneumatised as the middle turbinate is a not frequent anatomic variation that should be taken into account in preendoscopic CT evaluation of the paranasal sinuses.
La pneumatisation du cornet nasal supérieur : une variation anatomique courante ?
Résumé Les variations anatomiques sont importantes à connaitre dans le cadre du bilan tomodensitométrique précédant une chirurgie endoscopique des sinus paranasaux. Dans cette étude, nous avons recherché si le cornet nasal supérieur pouvait être pneumatisé comme l'est le cornet nasal moyen, entité anatomique bien connue. Les images de 52 patients ayant eu une tomodensitométrie avant chirurgie endoscopique et montrant des cellules ethmoïdales postérieures normalement pneumatisées et une cavité nasale nonopaque, ont été évaluées rétrospectivement. Les patients, 28 femmes et 24 hommes, étaient âgés de 12 à 68 ans (moyenne : 35 ans). La pneumatisation du cornet nasal supérieur a été classée en deux groupes; minime et prononçée. Cette pneumatisation était patente chez 25 patients (48 %). Treize pneumatisations unilatérales (25 %) et 8 pneumatisations bilatérales (15 %) furent retrouvées dans le groupe présentant une pneumatisation minime alors que 1 pneumatisation unilatérale et 3 bilatérales (8 %) étaient présentes dans le groupe dont la pneumatisation était plus marquée. Les cornets nasaux supérieurs semblaient être aérés par les cellules ethmoïdales postérieures. Les cornets nasaux supérieurs peuvent être pneumatisés, comme le sont les cornets nasaux moyens, avec une fréquence non-exceptionnelle. Cette variation anatomique mérite d'être prise en considération dans le bilan tomodensitométrique précédant toute chirurgie endoscopique des sinus paranasaux.相似文献
39.
Our report concerns a patient with a climacterium praecox and an X-chromosomal anomaly (86% 46, XX; 7% 47, XXX; 7% 45, X0) desiring to give birth. She conceived once after down-regulation of the gonadotrophins by means of a cyclical hormone replacement therapy followed by gonadotrophin stimulation, as well as a second time under down-regulation with a GnRH-analogue and gonadotrophin stimulation. On the basis of the case report and of the literature, a possible interval therapy in such a patient, especially one even with increasing ovarian insufficiency, will be portrayed and discussed. 相似文献
40.