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1.
Zymosan-induced chemiluminescence was investigated in whole blood and in neutrophils: in both, the peak count was frequently elevated in Beh?et's disease, and was significantly higher than in healthy controls; similarly the peak time was shorter. There were more uncommon serotypes of Streptococcus sanguis in the oral flora of patients with Beh?et's disease. Common serotypes were present in the flora of healthy controls, but not in patients with the disease. The percentage of Strep. sanguis in the oral flora was significantly correlated with the level of chemiluminescence response. Thus infection with uncommon serotypes of Strep. sanguis may play a role in the aetiology of Beh?et's disease.  相似文献   
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A case of undifferentiated carcinoma arising in the minor salivary gland is reported. Preoperative chemotherapy, surgery and postoperative immunotherapy were performed and good results were obtained for 15 months after surgery. However, metastasis to the lung occurred 18 months after surgery. The histologic diagnosis, clinical findings and origin of this tumor are discussed.  相似文献   
3.
The efficacy of enamel matrix derivative (EMD) as an adjunct to periodontal regenerative therapy has been demonstrated in recent clinical studies, however, little is known about its molecular mechanism (s). We examined the mitogenic response of cultured periodontal ligament (PDL) cells to EMD and characterized associated changes in proliferation-related intracellular signaling molecules, including mitogen-activated protein kinases (MAPK) and Akt kinases/protein kinase B (Akt/PKB) kinases. The DNA synthesis of PDL cells increased following treatment with EMD at concentrations higher than 1 microg ml(-1). This mitogenic response to EMD was associated with the selective activation of extracellular signal-regulated kinase (ERK) 1/2. No other MAPKs, or Akt/PKB kinases, responded to EMD stimulation. The EMD induction of DNA synthesis and activation of ERK 1/2 were diminished by pretreatment with suramin, an inhibitor of receptor tyrosine kinases (RTK). The signaling pathway induced by EMD from RTK to ERK 1/2 was similar to that activated by epidermal growth factor (EGF), although the specific binding of 125I-EGF to PDL cells was not affected by pretreatment or concomitant treatment with EMD. These findings suggest that EMD elicits its mitogenic signal through an EMD-specific RTK towards ERK 1/2.  相似文献   
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Abstract By cephalometric and dental cast analyses, the effects of corticotomy in combination with 45–50 days retraction of the maxillary anterior segment were evaluated in five female Japanese monkeys (Macaca fuscata). In addition, microscopic changes of the related sutures were examined. According to the analyses of the dental casts, the retraction of the maxillary anterior segment m the experimental group was increased when compared with that of the control group.‘There was no change in Occlusal molar relationship. The cephalometric analysis revealed that the “Point A” and “Metal Implant” on the mid-sagittal site between the upper central incisors in the experimental group showed more pronounced retraction than that in two untreated control animals. These results were histologically evaluated by changes of the suture structure: irregularity of functional arrangement of component cells and fibers, an increase in number of cells, resorption and formation of bone, and an enlargement of the suture width. Resorption of tooth roots and alveolar bone, and irregularity of the periodontal ligament were observed. In general, these histological changes appeared more extensive in the control specimens compared with the experimental Specimens. The osseous histological changes were mainly observed in the compact bone area, while in the spongy bone area of both control and experimental specimens only minimal changes occurred. These results demonstrated the efficacy of combining a corticotomy procedure with retraction of the maxillary anterior bone segment by an orthodontic force.  相似文献   
8.
We investigated a relationship between sialographic findings of parotid glands and histopathologic changes of labial glands, in relation to Sj?gren's syndrome. We examined 107 patients, suspected to have Sj?gren's syndrome because of dry mouth and dry eyes, in whom no other autoimmune diseases were diagnosed. Parotid sialography identified 37 patients with punctate, globular, cavitary, or destructive sialectasia (S-positive group). These sialographic findings were not seen in the other 70 patients (S-negative group). Among these patients, 54 demonstrated periductal lymphocytic infiltration in the labial glands (H-positive group), whereas the other 53 patients did not demonstrate this histologic finding (H-negative group). Significant differences in stimulated parotid salivary flow rate and incidence of keratoconjunctivitis sicca were observed between patients in the S-positive and the S-negative groups. Differences in the salivary flow rate and the incidence of keratoconjunctivitis sicca were also seen between patients in the H-positive and the H-negative groups, although the differences were not statistically significant. The rate of incidence of serum rheumatoid factor, anti-SS-A, and anti-SS-B antibodies were significantly higher in the S-positive and the H-positive groups than in their negative counterparts.  相似文献   
9.
This study was designed to determine the effects of the heat curing time on a urethane tetramethacrylate (UTMA)-based hybrid resin and specifically on the degree of conversion (DC) and cytotoxicity. The materials used in this study were Estenia, a new-generation hybrid resin, and an experimental fiber reinforcement, Br-100. The DC values of the hybrid resin samples were measured using a Fourier transform infrared (FTIR) spectrophotometer after 180s of light curing followed by heat curing (0, 15, 30, and 60min). A method comparing intensities of C = C and N—H vibrations of the sample was used to calculate the final DC values. FTIR spectra were measured both inside and on the surface of the sample. The calculated DC values increased by increasing the heat curing times. After light curing only and after 15-min heat curing, the DC values inside the samples were smaller than the corresponding DC values at the surfaces of the samples. After 60min of heat curing, the samples achieved homogeneous polymerization (DC% = 65). The cytotoxicity of the material was studied from the glass fiber-reinforced hybrid resin samples, which were first light cured and then heat cured (15, 30, and 60min). Cytotoxicity was tested using both direct contact and extract methods. For the extract tests, the test specimens were incubated in a cell culture media at 37°, 54°, or 72°C for 24h. The heat curing times used had no effect on cytotoxicity. The incubation temperature, however, did have a significant effect. The extract obtained from 72°C incubation showed a cytotoxic effect whereas the others did not. The direct contact test did not show cytotoxicity.  相似文献   
10.
The uptake of NM394, a new quinolone, by and its subsequent elution from human polymorphonuclear leukocytes were studied and compared with those of ofloxacin and ciprofloxacin. The kinetics of the uptake of NM394 was similar to that of ciprofloxacin. The maximum intracellular-to-extracellular concentration ratio was 12.3, compared with 8.6 for ciprofloxacin and 4.9 for ofloxacin at the extracellular concentration of 20 micrograms/ml. The elution of NM394 from human polymorphonuclear leukocytes occurs relatively slowly; 5 min after the removal of extracellular NM394, nearly 100% still remained in polymorphonuclear leukocytes, compared with ofloxacin, which was so rapidly eluted that only 12% remained. The uptake of NM394 was significantly decreased at 4 degrees C and by the presence of NaCN but was not affected by the presence of L-glycine, L-leucine, L-serine, adenosine, or NaF. NM394 showed intracellular activity at a concentration of 0.1 microgram/ml that significantly reduced the number of phagocytosed Pseudomonas aeruginosa cells with 2 h of incubation. These results suggest that uptake of NM394 by human polymorphonuclear leukocytes occurs via an active transport system differing from that of ofloxacin, whose uptake is affected by the presence of L-glycine and L-leucine, and that once accumulated, NM394 remains intracellularly active and participates in protection against bacterial infection.  相似文献   
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