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991.
Fourty-four narcotized rats were split into two equal groups, one being treated with nimodipine and the other with a placebo. By use of norfenefrine the blood pressure was raised to values of 150 and 180 mm Hg within the limits of the autoregulation of brain perfusion and under continuous measurement. Fifteen minutes after application of the standard tracer, horseradish peroxidase, the animals were exsanguinated using a saline perfusion and then perfusion-fixed with Karnovsky's solution. After development of the peroxidase staining the brain sections were evaluated and then allocated to their respective groups. In brain tissues from the experimental group significantly more frequent perivascular accumulations of horseradish peroxidase reaction product were found (P less than 0.001). In electron micrographs it could be seen that the tight junctions were intact and that there was a neuroendothelial transport, with horseradish peroxidase-filled vesicles, in the endothelium, muscle cells, and brain parenchyma. These vesicles represent a medium of transport for all proteins of high molecular weight and can therefore result in brain edema. It is concluded that nimodipine damages the blood-brain barrier by disturbance of the autoregulation of the cerebral blood flow.  相似文献   
992.
993.
Modification of a hand splint for a musician who had suffered an incomplete disruption of the left ring finger extensor tendon is described. This modification enabled the patient to receive the benefit of conservative treatment of this disruption while continuing his employment. The modification can be performed easily with the standard stack splint; the success of this method is described.  相似文献   
994.
Zusammenfassung In einer In-vitro-Studie wurde die Einsatzfähigkeit des Prophy-Jet-®-Gerätes für die Schmelzpolitur nach Bracketentfernung untersucht. In die Studie wurden drei verschieden stark gefüllte orthodontische Kleber einbezogen: Concise®, Genie® und Mono Lok®. Alle Proben wurden rasterelektronenoptisch untersucht und fotografisch dokumentiert in Vergrößerungen zwischen 20- und 10 000fach. Die Oberflächenanalyse ergab, daß das Prophy-Jet®-Gerät allein zur Schmelzpolitur nach Bracketentfernung nicht ausreicht, um unter klinisch vertretbarem Zeitaufwand (1 Minute/Zahn) eine kunststofffreie Schmelzoberfläche zu erzielen. Nach konventioneller makroskopischer Vorreinigung mit Scalern oder rotierenden Hartmetallfinierern zeigten sich nach fünfsekündiger Prophy-Jet®-Bestrahlung noch geringe Kleberreste. Nach zehnsekündiger Expositionsdauer waren beim Mono Lok®-Adhäsiv keine Kleberreste mehr nachweisbar, beim Concise®-bzw. Genie®-Adhäsiv fanden sich noch vereinzelte geringe Kleberinseln. Das Prophy-Jet®-Gerät erscheint zur Unterstützung der Schmelzpolitur nach Bracketentfernung sinnvoll; eine sorgfältige Vorreinigung mit Hand- oder rotierenden Instrumenten ist jedoch erforderlich, um eine weitgehende Adhäsivreduktion zu erreichen. Die konventionelle Gummi- und Bimssteinpolitur kann nach 20sekündiger Prophy-Jet®-Bestrahlung entfallen.
Summary The purpose of this in vitro investigation was to ascertain the effects of the Prophy-Jet® air-powder abrasive system for enamel polishing after debonding. Three adhesives differing in filler content were included in this study: Concise®, Genie®, and Mono Lok®. All specimens were examined by scanning electron microscopy and documented photographically at magnifications from 20 to 10 000. Surface analysis showed that using the Prophy-Jet® exclusively is not sufficient to produce a clean and smooth enamel surface without residual adhesive after debonding and after one minute of exposure time, as might be justifiable in a clinical situation. After macroscopic conventional clean-up with scalers or rotary finishing instruments and five seconds of exposure time to the Prophy-Jet® some occasional adhesive remnants could be located. After ten seconds of Prophy-Jet® treatment all Mono Lok®-adhesive was removed from the enamel surface; in the Concise® and Genie®-group few isolated adhesive remnants could be detected. The Prophy-Jet® air-powder abrasive system was found to be efficient in supporting enamel polishing after debonding; but an accurate pretreatment with scalers or rotary finishing instruments is essential to achieve an extensive reduction of adhesive. Final polishing of the enamel surface with rubber wheels or prophy cup and pumice can be omitted after treatment with the Prophy-Jet® for 20 seconds.

Résumé Le but de ce travail était d'éxaminer à l'aide d'une étude in vitro, l'emploi du Prophy Jet® pour le polissage de l'émail après l'arrachage des brackets. Dans l'étude on a analysé trois substances adhésives différentes: Concise®, Genie® et Mono Lok®. Après avoir examiné les spécimens par le microscope électronique à balayage, on les a documentés à l'aide de photos d'un grossissement de 20 à 10 000. L'analyse de la surface montre que la seule application du Prophy Jet® (après l'arrachage des brackets) ne suffit pas pour obtenir une surface d'émail sans substance adhésive en un temps clinique d'une minute par dent. Après prétraitement macroscopique selon la méthode conventionnelle (scaler ou instruments montés sur tour) il demeurait encore de petits restes de la substance adhésive après l'application du Prophy Jet® pendant cinq secondes. Après une durée d'application de dix secondes, on ne pouvait pas déceler de restes de Mono Lok®, tandis qu'il y avait sporadiquement des restes de Concise® et Genie®. Ces résultats indiquent, que le Prophy Jet® est efficace pour le polissage de l'émail après l'arrachage des brackets, mais on a tout de même besoin d'un nettoyage précédent minutieux avec des instruments convenables (scaler ou instruments montés sur le tour) pour obtenir une réduction considérable de la substance adhésive. On peut renoncer au polissage conventionnel à l'aide de caoutchouc ou de la pierre ponce après l'application du Prophy Jet® pendant 20 secondes.


Vortrag auf der wissenschaftlichen Jahrestagung der Deutschen Gesellschaft für Kieferorthopädie 1985.  相似文献   
995.
Roentgen diagnosis of midfacial fractures   总被引:1,自引:0,他引:1  
M Litwan  C Fliegel 《Der Radiologe》1986,26(9):421-426
The course and configuration of typical maxillofacial fractures (type Le Fort I-III) and lateral maxillary fractures including the zygomatic arch were reconstructed in detail by application of barium paste on a bony skull and radiographs in standard projections were performed and evaluated. It was obvious from the resulting radiographs that for most maxillofacial fractures a half axial or Water's view was most helpful. Lateral views only give additional information when there is a considerable degree of dislocation of fragments. Comparison with a pediatric skull of 8 years of age demonstrated that fractures of the zygomatic arch in this age group cannot be demonstrated by the typical submento-vertical view, but are shown on a Towne projection. The radiographic appearance of important maxillofacial fractures is demonstrated. The necessity of further studies in cases where reconstructive surgery appears necessary is discussed and CT rather then conventional tomography is advocated.  相似文献   
996.
We investigated the degree and time course of neutrophil sequestration into human lungs during cardiac operations. At the same time, measurement of the concentration of peroxidation products in the plasma was used as an index of oxidant free radical activity. The study was performed in two groups of patients. Group A (n = 11) had studies extending over the entire operative period and showed a highly significant sequestration of neutrophils into the lung, together with a highly significant (p less than 0.001) rise in peroxidation products from 2.8 +/- 0.12 nmol/ml(mean +/- standard error of the mean)before bypass to a peak of 5.05 +/- 0.13 nmol/ml at the end of bypass. As these changes occurred only during the time after release of the aortic cross-clamp, we investigated this period in more detail in a second group of patients (Group B, n = 7). Results from this group showed that significant release of peroxidation products occurred at the same time as pulmonary neutrophil sequestration. This study has produced evidence of increased oxidant activity in the lung associated with cardiac operations. Nevertheless, it is not known whether the neutrophils sequestered into the lung alone induced the increased activity. Similarly, whether neutrophil-derived oxidant species are the sole cause of lung tissue injury remains unproved.  相似文献   
997.
19 polygraphic sleep recordings from 12 patients with Pick's Disease, including four histologically proved cases, were compared to those of an age-matched control group. Symptoms had been present for a mean 8 years, the patients being aged 59 to 78 (mean 70.5 years). All sleep stages could be identified. Total sleep time was reduced and the number of awakenings was sharply increased. High proportion of stage 1 contrasted with the reduction in the other sleep stages with disappearance of stage 4 in advanced cases. REM Sleep was identified in all recordings, although reduced as a function of the length of the illness; its production as a function of total sleep time was not different from that of the control. REM Sleep appeared often fragmented and with a remarkably short latency, reminiscent of that observed in severely depressed patients.  相似文献   
998.
Slowly progressive aphasia without generalized dementia is a degenerative syndrome selectively affecting dominant hemisphere language areas. We report changes in regional glucose metabolism measured by positron emission tomography in two patients with this condition. Striking abnormalities of glucose utilization in the left cerebral cortex were demonstrated in both patients. The findings of other neurodiagnostic studies were relatively unremarkable. The first patient had a 3-year history of progressive anomia and impaired auditory verbal recall. An electroencephalogram was normal, and computed tomography showed mild left perisylvian atrophy. Positron emission tomography revealed profound hypometabolism in the left temporal regions. The second patient also had a 3-year history of progressive anomia. Electroencephalography, computed tomography, and magnetic resonance imaging scans were normal. Positron emission tomography showed a major reduction in left parietal glucose utilization, with a lesser decrement in left temporal metabolism. Neither patient demonstrated significant contralateral or global abnormalities such as those reported in positron emission tomographic studies of Alzheimer's disease with or without focal clinical features. These observations support the concept of adult-onset progressive aphasia without dementia as a clinical syndrome distinct from Alzheimer's disease.  相似文献   
999.
Bronchial venous plexus and its communication with pulmonary circulation   总被引:2,自引:0,他引:2  
This study was undertaken to clarify the microvascular anatomy of the normal human bronchial circulation, focusing on the bronchial venous system and its communication with the pulmonary circulation. Ten normal lungs obtained at autopsy were studied. Bronchial arteriography was performed in six lungs, pulmonary arteriography in two lungs, and pulmonary venography in another two. Using radiologic methods, including microradiography, and serial histologic sections, we found numerous bronchial venous plexuses around the airways and blood vessels into which the bronchial capillaries drained. Frequent communications of the venous plexuses with the pulmonary veins and neighboring alveolar capillaries were also demonstrated. The bronchial venous plexus and its close connection with the pulmonary circulation may be important in various pathologic conditions involving the interstitial space, such as interstitial pulmonary edema.  相似文献   
1000.
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