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A large number of direct bonding systems have been introduced for use by dentists and dental hygienists. Although these agents are used for direct bonding of brackets to enamel, contact with skin, oral mucosa, and gingiva is not uncommon. These products have wide clinical use, but their biocompatibility characteristics have not been extensively investigated. The present study was undertaken to determine the effects of the primer component of Mono-Lok (Rocky Mountain) and the primer component of Control (Lancer Pacific) on skin. Three adult Macaca mulatta monkeys were used in the study. The skin on their backs was shaved and the primer component of Control, primer component of Mono-Lok, and saline solution were applied at different sites every 3 days for up to four applications. The skin was examined clinically and, 5 days after the last application, a biopsy was performed for histologic evaluation. The skin in contact with the primer component of Mono-Lok exhibited pronounced inflammatory changes and was characterized by swelling, vesiculation, and ulceration. Histologic observations confirmed these findings by showing a marked inflammatory cellular response characterized by eosinophils. In contrast to these findings, the skin in contact with the primer component of Control or saline solution exhibited normal architecture. Histologic observations supported this appearance and showed minimal inflammatory cell infiltration. These results show that there are differences in the biocompatibility of direct bonding systems and that further studies are needed to clarify their long-term effects on patients and dental personnel. 相似文献
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S L Gardini U Sergiacomi G G Colarossi 《Quaderni Sclavo di diagnostica clinica e di laboratorio》1987,23(1):32-42
New parametric and non parametric statistical methods have been compared in the evaluation of experimental data of CEA and CA 19.9 using a brief program in BASIC. We have found that the distribution of the two markers is the same of that described in literature except for both the means that we have found being slightly higher than that ones described by other authors. 相似文献
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K. E. Schneweis M. Brado B. Ebers A. Friedrich M. Olbrich W. Schüler 《Medical microbiology and immunology》1987,177(1):1-8
In the model of genital herpes simplex virus (HSV)-infection of mice, early latency could be induced by passive immunization with HSV-specific antibodies and, to a lesser degree, by adoptive transfer of immune lymphocytes prepared from spleen and draining lymph nodes of genitally infected syngeneic mice. Conversely, spontaneously occurring latency was inhibited by treatment of the animals with cyclophosphamide (Cph) and, to a lesser degree, with cyclosporin A (CyA). Whereas the effect of CyA could be compensated by passively administered HSV-specific antibodies, that of Cph could not. Apparently specific antibodies cooperate with a non-specific proliferating cell type, probably macrophages and/or NK-cells, as could be demonstrated by significantly reduced antibody effect in silica-treated mice. Moreover, F(ab)2 fragments, in contrast to complete antibody molecules, were inactive. HSV-specific antibodies and also immune lymphocytes had little effect on virus production in the mucous membranes, immune lymphocytes being at least as active as antibodies. It is therefore not probable that latency is induced by attenuation of the peripheral disease. It can rather be concluded that the neuron itself is the target for the action of specific antibodies, cooperating in turn with macrophages and/or NK cells.With support of the Deutsche Forschungsgemeinschaft, Schn 174/6-3 相似文献
1000.
P M Battey J T Fulenwider R B Smith L G Martin M T Stewart G D Perdue 《Southern medical journal》1987,80(4):479-482
Peripheral arterial thromboembolism and thrombosis of arterial grafts continue to threaten viability of extremities. Percutaneous intra-arterial thrombolysis (IAT) and angiodilatation have afforded limb salvage in some of these patients. Proper patient selection appears to be the hallmark of success with IAT. During a recent three-year period, we used IAT in 32 extremities in 28 patients who had acute arterial insufficiency. Before IAT, 16 extremities were painful at rest, and 16 had incapacitating claudication. The overall success rate was 38%, but some degree of thrombolysis occurred in 88%. Limb salvage was achieved in 27 of 32 extremities (84%). Only five of 17 limbs (29%) with arterial graft thrombosis required no operation or an operation of lesser magnitude than predicted before IAT. Of six extremities with native arterial embolism, four (67%) were completely cleared with IAT. Major complications occurred in eight cases (25%), with two IAT-related deaths (6%). This study suggests that IAT is best reserved for individuals with acute limb ischemia caused by arterial embolus, those whose degree of ischemia would tolerate a 24-hour trial of IAT, and those whose femoral or tibial runoff is not likely to require remedial operation. 相似文献