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991.
Sarcoidosis is a chronic, multisystem disorder of unknown cause characterized by noncaseating epithelioid granulomas. Infectious agents and genetic components have been discussed. Heerfordt’s syndrome with uveitis, enlargement of the parotid glands and optional paralysis of the Nn. facialis is a form of sarcoidosis. The diagnosis is confirmed by histology. Further analyses are fiberoptic bronchoscopy with bronchoalveolar lavage or the gallium-67 scan in combination with blood findings. The therapy of choice is glucocorticoids. We present a case report of Heerfordt’s syndrome and a review of the literature covering different aspects of sarcoidosis.  相似文献   
992.
External cervical resorption of a primary canine   总被引:1,自引:0,他引:1  
Summary. The authors describe the case of a 3-year-old boy who presented with a mobile right maxillary primary canine. Clinical examination revealed this tooth to have an abnormally large crown, which appeared to have sustained a crown–root fracture. Periodontal probing depths of 5 mm were detected around the tooth. Radiographically, there was a marked constriction at the cementoenamel junction with associated alveolar rarefaction. Both upper primary canines were subsequently removed under general anaesthetic and the right canine was subject to histopathological investigation. A diagnosis of external cervical resorption was made. A review of the literature confirmed this to be a very unusual case presentation.  相似文献   
993.

Objective

The objective of this study was to describe the changes in salivary protein profiles in infants between the ages of 3 and 6 months, and to evaluate the impact of teeth eruption and introduction of solid foods on such profiles.

Design

73 infants were followed longitudinally at 3 and 6 months of age. Their whole saliva proteins were separated by SDS–PAGE electrophoresis and semi-quantified by image analysis. Amylase activity was also measured on a sub-sample of the population (n = 42 infants). Bands which abundance was significantly different between the two ages according to paired comparisons were identified by mass spectrometry techniques.

Results

Out of 21 bands, 13 were significantly different between 3 and 6 months of age. Two short variants of amylase increased in abundance with age, as did amylase activity. Other changes possibly translated developmental physiological events, for example maturation of the adaptive immune system. The balance between S-type cystatins and cystatins A and B was modified, in favour of S-type cystatins at 6 months of age. Teeth eruption resulted in an increase in albumin abundance, whilst introduction of solid foods was associated with higher levels of β-2 microglobulin and S-type cystatins.

Conclusions

Salivary profiles were modified substantially between the ages of 3 and 6 months. Both teeth eruption and diet had an impact on abundance changes for some proteins, revealing dynamic interactions between saliva proteome, oral physiology and diet.  相似文献   
994.
Most foreign bodies pass through the gastrointestinal tract uneventfully. The majority of the reported literature describes the management of ingested blunt objects. However, ingestion of sharp objects can still occur with a higher rate of perforation corresponding to treatment dilemmas. We report a case of inadvertently ingested sharp foreign body by a special child, which was retrieved by endoscopic guided forceps. Urgent endoscopic assessment and retrieval of recently ingested sharp dental foreign body is indicated and routine use of preventive measures such as rubber dam, gauze throat screens or floss ligatures is suggested.  相似文献   
995.
996.
The increased availability of devices for 3D radiological diagnosis allows the more frequent use of CAD/CAM-produced surgical guides for implant placement. The conventional workflow requires a complex logistic chain which is time-consuming and costly. In a pilot study, the workflow of directly milled surgical guides was evaluated. These surgical guides were designed based on the fusion of an optical impression and the radiological data. The clinical use showed that the surgical guides could be accurately placed on the residual dentition without tipping movements. The conventional surgical guides were used as a control for the manual check of the deviation of the implant axis. The direct transfer of the digital planning data allows the fabrication of surgical guides in an external center without the need of physical transport, which reduces the logistic effort and expense of the central fabrication of surgical guides.  相似文献   
997.
Keratocystic odontogenic tumours (KOCTs) are common benign cystic tumours that arise sporadically or associated with nevoid basal cell carcinoma syndrome (NBCCS). PTCH mutation can be found in sporadically or NBCCS associated KOCTs. Few PTCH mutations in families with non-syndromic KOCTs have been reported. Through PCR and gene sequence analysis, the authors discovered one missense mutation c.3277G>C in exon 19 of PTCH gene in a Chinese family with non-syndromic KOCTs. This mutation causes one highly conserved glycine residue transit to arginine on the 10th transmembrane region of PTCH protein. This work revealed that the missense mutation of PTCH is the causative and dominant gene of KOCTs in this family.  相似文献   
998.
The objective of this study was to examine the impact of mechanical loading on solute transport in porcine temporomandibular joint (TMJ) discs using the electrical conductivity method. The electrical conductivity, as well as ion diffusivity, of TMJ discs was determined under confined compression with 3 strains in 5 disc regions. The average electrical conductivity over the 5 regions (mean ± SD) at 0% strain was 3.10 ± 0.68 mS/cm, decreased to 2.76 ± 0.58 mS/cm (-11.0%) at 10% strain, and 2.38 ± 0.55 mS/cm (-22.2%) at 20% compressive strain. Correspondingly, the average relative ion diffusivity (mean ± SD) at 0% strain was 0.273 ± 0.055, decreased to 0.253 ± 0.048 (-7.3%) at 10% strain, and 0.231 ± 0.048 (-15.4%) at 20% compressive strain. These results indicated that compressive strain impeded solute transport in the TMJ disc. Furthermore, our results showed that the transport properties of TMJ discs were region-dependent. The electrical conductivity and ion diffusivity in the anterior region were significantly higher than in the posterior region. This regional difference is likely due to the significant differences of tissue hydration between these 2 regions. This study provides important insight into the electrical and solute transport behaviors in TMJ discs under mechanical loading and aids in the understanding of TMJ pathophysiology related to tissue nutrition.  相似文献   
999.
1000.
OBJECTIVE: High levels of serum anti-Actinobacillus actinomycetemcomitans immunoglobulin G (IgG) correlate with reduced extent and severity of periodontal disease and the present study was undertaken to begin testing the hypothesis that proinflammatory cytokines are important in the induction of optimal anti-A. actinomycetemcomitans IgG responses. BACKGROUND: Studies with pokeweed mitogen indicate that interleukin-1alpha (IL-1alpha) and IL-1beta are necessary for optimal IgG1 and IgG2 production and that prostaglandin E(2) (PGE(2)) and interferon-gamma (IFN-gamma) selectively promote IgG2, which is a major component of the anti-A. actinomycetemcomitans response in vivo. The pokeweed mitogen results suggest that these proinflammatory cytokines would also be necessary for optimal production of IgG specific for A. actinomycetemcomitans. METHODS: Peripheral blood mononuclear cells from A. actinomycetemcomitans-seropositive subjects with localized aggressive periodontitis were stimulated with A. actinomycetemcomitans in immune complexes capable of binding follicular dendritic cells that participate in the induction of recall responses in vivo. Cultures were manipulated with anti-IL-1alpha, anti-IL-1beta, anti-IFN-gamma, anti-IL-12, anti-CD21, indomethacin, and PGE(2). Actinobacillus actinomycetemcomitans specific IgG production was monitored by enzyme-linked immunosorbent assay (ELISA). RESULTS: Addition of follicular dendritic cells to peripheral blood mononuclear cells cultures resulted in follicular dendritic cell-lymphocyte clusters and increased anti-A. actinomycetemcomitans IgG responses (3-40-fold increases) compared with controls lacking follicular dendritic cells. Anti-IL-1alpha, anti-IL-1beta, anti-IFN-gamma, anti-IL-12, anti-CD21 and indomethacin suppressed anti-A. actinomycetemcomitans IgG production by half or more. PGE(2) restored IgG responses suppressed by indomethacin. CONCLUSIONS: The cytokines IL-1alpha, IL-1beta, IFN-gamma, IL-12, and PGE(2) were all necessary for optimal production of human anti-A. actinomycetemcomitans and the need for proinflammatory cytokines including the T helper 1 (Th1) cytokines is consistent with a response with a significant IgG2 component.  相似文献   
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