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931.
The primary antigen-specific antibody response of various strains of mice to TEPC-15/PnC immune complexes has been examined. We found that both BALB/c and C3H mice were good responders to the PnC antigen; however, C3H mice were low responders, whereas BALB/c mice were high responders to the TEPC-15/PnC complexes. Using congenic strains on the C3H and BALB/c background, we have shown that the response to the complexes is not restricted by gene products of the H-2 complex or by the Igh (allotype) locus. However, responsiveness may be controlled by genes linked to the Igh locus, since we have shown that strains that are Ighj, Ighd, and Ighf are low responders, whereas strains that are Igha, Ighb, and Ighe are high responders to the immune complex. Moreover, responsiveness correlates with the expression of the T15 Id as measured using the anti-T15 monoclonal antibody, AB1-2. Thus, strains such as BALB/c, BALB.B, BALB.K, and CB-20, which express high levels of T15 (AB1-2) Id in their PFC response to PnC are relatively high responders to TEPC-15/PnC complexes, whereas C3H, C3H.SW, and C3H-OH, which express low levels of the T15 (AB1-2) Id, are low responders to the complexes. Finally, we found that BALB/c mice are high responders to complexes formed with T15+ antibodies, whereas they are low responders to complexes formed using T15- antibodies. The results suggest that the antigen-specific response to these immune complexes is Id-restricted.  相似文献   
932.
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   
933.
Lewis rats were immunized with a homogenate of human spinal cord. Splenocytes from the immunized rats were fused with cells from the SP2/0-Ag14 cell line to form hybrids that were subsequently screened immunohistochemically for secretion of antibodies against myelin. Thirty hybrids secreting anti-myelin antibodies were cloned. One secreted antibody (774) that immunohistochemically stained central nervous system (CNS) myelin but not peripheral nervous system (PNS) myelin also bound to the surface of peripheral blood macrophages. Hence we have identified an epitope that is shared by peripheral blood macrophages and CNS myelin.  相似文献   
934.
Necrosis of the femoral head following fracture of the femoral neck   总被引:2,自引:0,他引:2  
P Nordkild  S Sonne-Holm 《Injury》1986,17(5):345-348
One hundred and thirty fractures of the femoral neck treated with sliding screw-plate or sliding nail-plate were followed for up to 65 months postoperatively. Throughout the observation period the yearly incidence of necrosis of the femoral head was between 5 and 10 per cent, as estimated by the life table method, and after 5 years 37 per cent of the patients with united fractures had developed necrosis of the femoral head. The cases of necrosis were all characterized radiographically by one or more areas of subchondral cortical depression, generalized subchondral fragmentation or isolated patches of sclerosis. It is concluded that estimation of the frequency of femoral head necrosis after fracture of the femoral neck requires long-term follow-up and reliable, reproducible radiographical criteria for necrosis of the head. Because of the high mortality of patients sustaining these fractures, statistical methods employing censored data should be used.  相似文献   
935.
936.
937.
938.
Previous work from this laboratory reported on the effects of several autacoids and other agents on strips of human corpus cavernosum (cc) muscle. These investigations indicated the presence in the cc muscle of a) atropine-sensitive cholinoceptors, b) alpha- and beta-adrenoceptors and c) a non-adrenergic non-cholinergic mechanism. Several recent publications have presented evidence in support of the possibility that vasoactive intestinal polypeptide (VIP) is an important, or the chief, transmitter in human penile erection. This paper describes the actions of VIP and other compounds on the cc muscle and the effect of intracavernous injection of VIP in volunteers. Among the agents tested, VIP was the most potent relaxant of the cc muscle. This effect, which was seen at a dose as low as 0.03 nM, was suppressed by VIP antiserum. The response of the isolated penile vasculature to VIP was similar. VIP antiserum had no effect on the relaxation of the cc muscle produced by field stimulation. In five of the seven subjects given intracavernous VIP (1.0 micrograms.) some degree of penile enlargement was evident, but none had an erection. It is suggested that local release of VIP, withdrawal of the alpha-adrenoceptor mediated tonic supply to the penis and the activation of the latter's beta-adrenoceptors are all probably involved in penile erection in man.  相似文献   
939.
This study measured the pressures under the three most commonly used digital tourniquets--the Penrose drain, the rolled rubber glove, and the rubber band. A miniature pressure transducer and a digital strain indicator were used to measure pressures generated by the various tourniquets. The rolled rubber glove technique was highly consistent, irrespective of the clinical experience of the subject, and uniformly generated pressures of less than 500 mm Hg. Pressures generated by Penrose drains and rubber bands were highly variable and were significantly greater than 500 mm Hg. The so-called calibrated Penrose drain generated the highest pressures in the study. The relationship between tourniquet pressures and neurovascular injury in the human digit is not clearly defined.  相似文献   
940.
AIDS: what is now known. I. History and immunovirology   总被引:1,自引:0,他引:1  
  相似文献   
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