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61.
Purpose: The purpose of this study was to perform a longitudinal follow-up study of implant stability in grafted maxillae with the aid of clinical, radiological, and resonance frequency analysis (RFA) parameters. Materials and Methods: The atrophic edentulous maxillae in 29 patients were reconstructed with free iliac crest grafts using onlay/inlay or interpositional grafting techniques. The endpoint of the resorption pattern in the maxilla determined the grafting technique used. Endosteal implants were placed after 6 months of bone-graft healing. Implant stability was measured four times using RFA: when the implants were placed, after 6 to 8 months of healing, after 6 months and 3 years of bridge loading. Individual checkups were performed at the two later RFA registrations after removal of the supraconstructions (Procera® Implant Bridge, Nobel Biocare AB, Göteborg, Sweden). Radiological follow up of marginal bone level was performed annually. Results: Twenty-five patients remained for the follow-up period. A total of 192 implants were placed and with a survival rate of 90% at the 3-year follow up. Women and an implant position with a class 6 resorption prior to reconstruction were factors with significant increased risk for implant failure (multivariate logistic regression). Twelve of the 20 failed implants were lost before loading (early failures). The change in the marginal bone level was 0.3 ± 0.3 mm between baseline (bridge delivery) and the 3-year follow up. The implant stability quotient (ISQ) value for all implants differed significantly between abutment connection (60.2 ± 7.3) and after 6 months of bridge loading (62.5 ± 5.5) (Wilcoxon signed ranks test for paired data, p=.05) but were nonsignificant between 6 months of bridge loading and 3 years of bridge loading (61.8 ± 5.5). There was a significant difference between successful and failed implants when the ISQ values were compared for individual implants at placement (Mann-Whitney U test, p=.004). All 25 patients were provided with fixed implant bridges at the time of the 3-year follow up. Conclusion: This clinical follow up using radiological examinations and RFA measurements indicates a predictable and stable long-term result for patients with atrophic edentulous maxillae reconstructed with autogenous bone and with delayed placement of endosteal implants. The ISQ value at the time of placement can probably serve as an indicator of level of risk for implant failure.  相似文献   
62.
Aim: To evaluate, in young adults, the effect of different preventive programmes on oral hygiene and to determine whether the variables investigated are predictors of gingival health. Material and Methods: This randomized, blinded, parallel, controlled clinical study examined the effectiveness of three dental health programmes. Four hundred subjects aged 20–27 years, 211 males and 189 females, participated in the study. They were recruited from a Public Dental Service clinic and from a private dental practice in Jönköping, Sweden. The effect of the programmes on plaque and gingivitis was evaluated over a 3‐year period. The programmes included activities that were adapted for individuals as well as for groups. The plaque indices (PLI) and gingival indices (GI) were used to evaluate the programmes. Results: All programmes resulted in a decrease in PLI and GI. The greatest decrease was found in the group that was followed‐up every 2 months. Professional tooth cleaning was non‐significant for the clinical result. Gingival health at baseline, participation in any of the test programmes, and knowledge of the dental diseases caries, gingivitis or periodontitis were significant predictors of good gingival health. Conclusions: The study confirms the efficacy of three different preventive programmes in reducing supragingival plaque and gingival inflammation. Professional tooth cleaning provided no clinical benefit beyond that derived from individual and group‐based health education.  相似文献   
63.
AIM: The purpose of this study was to determine inter-examiner reproducibility of two modified Winkel tongue coating indices and to study the relationship between each of these two indices and the amount of tongue coating as determined by wet weight of scrapings from the dorsum of the tongue. MATERIALS AND METHODS: Twenty-five participants were selected for the study from among dental students. The selection was made to assure that a wide range of degrees of tongue coating were represented. Two independent examiners scored the tongue coatings using the two modified Winkel tongue coating indices (mWTCI 1 + 2 and mWTCI 2). After completion of index recordings, tongue scrapings were performed by one of the examiners. RESULTS: Inter-examiner reproducibility of mWTCI 1 + 2 and mWTCI 2 using Pearson's coefficients of correlation amounted to r = 0.48 and 0.93 respectively. Overall, mWTCI 2 showed higher correlations to wet weight of tongue scrapings than mWTCI 1 + 2. CONCLUSION: The mWTCI 2 was found to be highly reproducible and also valid as related to wet weight of tongue scrapings. This index would seem suitable for further studies on tongue coatings; effect of tongue cleaning; and rate of reformation of coatings after cleaning.  相似文献   
64.
BACKGROUND: Temperament has been associated with dental fear (DF) and dental behavioural management problems (DBMP) in children, but little is known about what role temperament plays in the aetiology of DF. Thus, measures of temperament suitable for use among children, adolescents, and adults would be of value for longitudinal and family studies of DF, where relations between children's and parent's ratings are investigated. AIM: Our aim was to explore the adapted EASI (emotionality, activity, sociability, and impulsivity) in adult patients, and to evaluate the instrument in comparison with established measures of DF and general emotional reactions in adults. DESIGN: The subjects were 230 adult patients applying for treatment for DF and 41 nonfearful patients (reference group). Questionnaires investigated temperament (general and DF) and general anxiety and depression. RESULTS: The previously described factor structure of the EASI among children was confirmed and the adapted EASI had acceptable psychometric qualities. Emotionality correlated with DF and with measures of general psychological distress. No differences were found in mean scores of EASI dimensions between DF group and the reference group, which was in contrast with studies in children. CONCLUSIONS: The adapted EASI seem promising for use in future longitudinal and familial studies of development of DF and DBMP.  相似文献   
65.
66.
Amyloid is the result of an anomalous protein and peptide aggregation, leading to the formation of insoluble fibril deposits. At present, 18 human diseases have been associated with amyloid deposits-e.g., Alzheimer's disease and Prion-transmissible Spongiform Encephalopathies. The molecular structure of amyloid is to a large extent unknown, because of lack of high-resolution structural information within the amyloid state. However, from other experimental data it has been established that amyloid fibrils predominantly consist of beta-strands arranged perpendicular to the fibril axis. Identification of residues involved in these secondary structural elements is therefore of vital importance to rationally designing appropriate inhibitors. We have designed a hydrogen/deuterium exchange NMR experiment that can be applied on mature amyloid to enable identification of the residues located inside the fibril core. Using a highly amyloidogenic peptide, corresponding to residues 25-35 within the Alzheimer Abeta(1-43) peptide, we could establish that residues 28-35 constitute the amyloid core, with residues 31 and 32 being the most protected. In addition, quantitative values for the solvent accessibility for each involved residue could be obtained. Based on our data, two models of peptide assembly are proposed. The method provides a general way to identify the core of amyloid structures and thereby pinpoint areas suitable for design of inhibitors.  相似文献   
67.

Background

Takotsubo cardiomyopathy (TCM) is characterized by regional left ventricular dysfunction that cannot be explained by an occlusive lesion in a coronary artery. Catecholamines are implicated in the pathogenesis of TCM but the mechanisms involved are unknown. Because the endogenous and the most commonly used exogenous catecholamines have well defined adrenoceptor subtype affinities, inferences can be made about the importance of each adrenoceptor subtype based on the ability of different catecholamines to induce TCM. We therefore studied which of five well-known catecholamines, that differ in receptor subtype affinity, are able to induce TCM-like cardiac dysfunction in the rat.

Methods

255 rats received intraperitoneally isoprenaline (β12-adrenoceptor agonist), epinephrine (β12/α-adrenoceptor agonist), norepinephrine (β1/α-adrenoceptor agonist), dopamine (α/β12-adrenoceptor agonist) or phenylephrine (α-adrenoceptor agonist). Each catecholamine was given in five different doses. We measured blood pressure through a catheter inserted in the right carotid artery and studied cardiac morphology and function by echocardiography.

Results

All catecholamines induced takotsubo-like cardiac dysfunction. Isoprenaline induced low blood pressure and predominantly apical dysfunction whereas the other catecholamines induced high blood pressure and basal dysfunction. In another set of experiments, we continuously infused hydralazine or nitroprusside to rats that received epinephrine or norepinephrine to maintain systolic blood pressure < 120 mm Hg. These rats developed akinesia of the apex instead of the base. Infusion of phenylephrine to maintain blood pressure > 120 mm Hg after isoprenaline administration prevented apical TCM-like dysfunction.

Conclusions

Catecholamine-induced takotsubo-like cardiac dysfunction appears to be afterload dependent rather than depend on stimulation of a specific adrenergic receptor subtype.  相似文献   
68.
Young children are very susceptible to typhoid fever, emphasizing the need for vaccination in under five age groups. The parenteral Vi polysaccharide vaccine is not immunogenic in children under 2 years and the oral Ty21a vaccine (Vivotif) available in capsular formulation is only recommended for those over 5 years.  相似文献   
69.
Major surgery is associated with substantial morbidity and mortality with early post-operative adverse events (POAE) occurring in 30% of patients within the first 30 days. The underlying pathogenesis is multifactorial, including immune dysfunction and increased inflammatory response to surgery. We investigated preoperative immune function by the TruCulture® whole blood technique in a cohort of patients undergoing pancreaticoduodenectomy (PD), hypothesizing that patients developing inflammatory POAE defined as leucocytosis, fever or high (above median) area under the curve (AUC) C-reactive protein (CRP) the first post-operative week would display perturbed preoperative immune function. Sixty-two adult patients were screened, 30 included and 11 excluded post-inclusion due to other surgical procedures than PD and post-operative complications directly attributed to surgery, leaving 19 patients for analysis of preoperative immune function. Patients developing leucocytosis (n = 5, 26%) had lower Toll-like receptor (TLR)-3–stimulated IL-12p40 and higher Candida Albicans (TLR1/2/4/6, Dectin-1)-stimulated TNF-α, compared to patients without leucocytosis (all P < .05). Patients developing fever (n = 7, 37%) had lower TLR7/8-stimulated IFN-γ and patients with high AUC CRP (n = 9, 47%) had lower TLR3-stimulated IFN-γ and IL-6 and lower TLR7/8-stimulated IL-10 (all P < .05), compared to patients without fever or low CRP, respectively. In conclusion, patients with inflammatory POAE displayed lower preoperative stimulated IL-12p40, IFN-γ, IL-6 and IL-10 and higher TNF-α response, compared to patients without inflammatory POAE. This finding suggests that TruCulture is a feasible immunologic screening tool in surgical patients, with a potential for preoperative identification of patients at increased risk for inflammatory POAE, allowing for risk-based intervention trials.  相似文献   
70.
Journal of Neurology - Continuous subcutaneous (s.c.) apomorphine infusion is an effective therapy for Parkinson’s disease (PD), but a limitation is the formation of troublesome s.c. nodules....  相似文献   
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