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Gingival squamous cell carcinoma represents less than 10% of diagnosed intraoral carcinoma. Many unique features of gingival squamous cell carcinoma clearly delineate it from oral squamous cell carcinoma arising in other sites. This article presents the clinicopathologic findings of a case. An 81-year-old woman presented for evaluation of multiple oral lesions primarily limited to the maxillary gingiva; the lesions had been present for about 2 years. Differential diagnosis included epithelial dysplasia, benign mucous membrane pemphigoid, inflammatory lesion of endodontic/periodontic origin, lichen planus, and squamous cell carcinoma. Clinical examination revealed extensive erythematous and ulcerative lesions of maxillary buccal and palatal gingiva extending into the maxillary buccal vestibule; the lesions did not respond to antibiotic therapy. Radiographic evaluation demonstrated advanced alveolar bone loss as well as displacement of the maxillary right first molar. Subsequent histology confirmed diagnosis of moderately differentiated squamous cell carcinoma. Gingival squamous cell carcinoma can mimic a multitude of oral lesions, especially those of inflammatory origin. In addition, predisposing and presenting factors are different from those of other oral squamous cell carcinomas. Careful examinations as well as routine biopsy are crucial for accurate diagnosis.  相似文献   
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The effect of dietary fats such as butter, lard, cottonseed oil, and hydrogenated cottonseed oil on the fatty acid composition of enamel and dentin lipids of rabbit molars was studied. The enamel and dentin of molars of all of the rabbits contained a variety of fatty acids, palmitic, stearic, oliec, linoleic, and eicosapentaenoic being the major ones. Enamal lipids were more unsaturated than dentinal lipids in all of the groups. A significant difference was noticed in the fatty acid composition of both the enamel and dentin between these four groups of rabbits. Linoleic acid content was highest in both the enamel and dentin lipids of rabbits fed cottonseed oil. There was no marked difference in the saturated-unsaturated fatty acid ratio in both the enamel and dentin among rabbits fed cottonseed oil, lard, and butter. It is concluded that tooth lipids are responsive to diets and are in direct equilibrium with dietary components.  相似文献   
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BACKGROUND: The purpose of this study was to investigate the relationship between transforming growth factor-beta 1 (TGF-beta1) in gingival crevicular fluid (GCF) and the periodontal status of subjects who were positive for the human immunodeficiency virus (HIV)-1. METHODS: Medical and demographic variables, including age, cigarette smoking, CD4 cell count, and viral load values, were recorded. At the baseline and 6-month visits, gingival index (GI), plaque index, bleeding on probing, probing depth (PD), and attachment loss (AL) were recorded, and GCF samples were taken with paper strips from three periodontitis sites (GI >0; PD > or =5 mm; AL > or =3 mm), three gingivitis sites (GI >0; PD < or =3 mm; AL = 0), and two healthy sites (GI = 0; PD < or =3 mm; AL < or =2 mm) in 25 subjects who were HIV-1(+). GCF TGF-beta1 levels were determined by enzyme-linked immunosorbent assays. A statistical software package was used to analyze the data. RESULTS: The mean amounts of GCF TGF-beta1 were greater in gingivitis and periodontitis sites than in healthy sites (P <0.0001). GCF levels of TGF-beta1 correlated with PD, AL, age, smoking pack-years, CD4 cell count, and viral load at the baseline and 6-month visits (0.0001 < P <0.05). An active site was defined as a site that had > or =2 mm new AL during the 6-month study period. An active patient was defined as a patient who had one or more active site(s) during the study period. Repeated-measures analysis of 18 active sites versus 182 inactive sites indicated that GCF TGF-beta1 levels were higher in active sites than in inactive sites (P <0.0001). Eleven of the 25 study subjects had active sites at the end of the 6-month study period. The mean GCF TGF-beta1 level and the mean AL and PD for these 11 active subjects were higher than for the 14 inactive subjects (P <0.0001). CONCLUSION: In subjects who are HIV-1(+), sites with high GCF levels of TGF-beta1 are at significantly greater risk for the progression of established periodontitis.  相似文献   
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In humans, intermittent and continuous theta‐burst stimulation (iTBS and cTBS) elicit long‐term changes in motor‐evoked potentials (MEPs) reflecting long‐term potentiation (LTP)‐ and depression (LTD)‐like plasticity in the primary motor cortex (M1). In this study, we used TBS to investigate M1 plasticity in patients with MSA. We also assessed whether responses to TBS reflect M1 excitability as tested by short‐interval intracortical inhibition (SICI), intracortical facilitation (ICF), short‐interval intracortical facilitation (SICF), and the input/output curves. We studied 20 patients with MSA and 20 healthy subjects (HS). Patients were clinically evaluated with the Unified Multiple System Atrophy Rating Scale. The left M1 was conditioned with TBS. Twenty MEPs were recorded from the right first dorsal interosseous muscle before TBS and 5, 15, and 30 minutes thereafter. In a subgroup of 10 patients, we also tested MEPs elicited by SICI, ICF, SICF, and input/output curves, before TBS. Between‐group analysis of variance showed that at all time points after iTBS MEPs increased, whereas after cTBS they decreased only in HS. In both subgroups tested, patients with predominant parkinsonian and cerebellar features, iTBS and cTBS left MEPs unchanged. MSA patients had reduced SICI, but normal ICF, SICF, and input/output curves. No correlation was found between patients' clinical features and responses to TBS and M1 excitability variables. These findings suggest impaired M1 plasticity in MSA. © 2013 International Parkinson and Movement Disorder Society  相似文献   
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IntroductionPostoperative pain after breast surgery is one of the major factors contributing to delay in mobilisation and prolonged hospital stay. A retrospective analysis was performed of patients undergoing skin sparing mastectomy and insertion of a subpectoral implant. The aim was to determine whether the use of an elastomeric local anaesthetic pump improved pain control and length of stay.MethodsTwenty-five consecutive patients undergoing the above procedure were sited with an elastomeric local anaesthetic infusion pump intraoperatively, in addition to standard regular and pro re nata analgesia. The control group comprised 25 patients undergoing the same procedure in the same year who received standard analgesia alone. Visual analogue scale scores were recorded for the duration of inpatient stay, as was any further analgesic requirement.ResultsThe median age was 51 years (range: 26–75 years) in the intervention group and 50 years (range: 28–70 years) in the control group. The mean visual analogue scale score was 0.28 (standard deviation [SD]: 0.61) at 24 hours for the intervention group and 1.84 (SD: 0.37) for the control group (p<0.0001). The mean length of stay was 1.8 days (SD: 0.71 days) for the intervention group and 2.28 days (SD: 0.94 days) for the control group (p=0.15). There were no complications involving catheter placement, leakage or toxicity relating to use of the local anaesthetic.ConclusionsThere was significantly reduced pain with the use of the local anaesthetic infusion pump. The elastomeric pump is a step towards enhanced patient recovery after breast surgery in the case of skin sparing mastectomy and subpectoral tissue expander reconstruction.  相似文献   
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