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1.
OBJECTIVE: The aim of this study was to test the effectiveness of a newly developed system, using masking noises with specific frequencies and amplitudes, adjusted to typical noises experienced during dental treatment such as the high-speed hand-held drill. METHOD AND MATERIALS: In accordance with an analysis of typical noises experienced during dental treatment, masking noises with specific frequencies (frequency range 0.02 to 20 kHz) and amplitudes were created, with the aim of reducing the patients' awareness of typical treatment noises by overlaying frequencies. Two hundred fifty-four outpatients (113 males, 141 females) with a mean age of 32 years (+/- 10.5 years) were enrolled in this study. Patients were treated 15 minutes with and 15 minutes without the masking noise. Patients and practitioners filled out questionnaires aimed to evaluate the effectiveness of the system, sensitivity to noise (scale 0 to 10; 0 = effective, 10 = noneffective), psychologic aspects, and statements of fear. RESULTS: There was a significant reduction in patients' awareness of noise using this system during dental treatment. Most of the patients regarded the masking noise as a pleasureable supplementation to common treatment and would select this manner of dental treatment employing the device again (81.5%); 48.2% said they were more relaxed. The system does not, in principle, interfere with dental treatment, and in most instances, the device does not impede the communication between practitioners and patients. CONCLUSION: The present study demonstrates that using masking noises during dental treatment reduces the sensitivity to drill noise, reduces fear and stress, and may be useful in dental practice as an adjunct to common dental treatment. 相似文献
2.
Brita Gaudecker 《Anatomy and embryology》1991,183(1):1-15
Summary The thymus develops from a paired epithelial anlage in the neck. This review considers how ectoderm (vesicula cervicalis) and endoderm (third pharyngeal pouch) contribute to the epithelial stroma of the thymus. Stromal elements of mesodermal origin are capillaries, septae and perivascular spaces and single invading cells. These elements separate the thymus into pseudolobuli. The thymus epithelial space and the perivascular spaces are always separated from each other by a closed, flat epithelial cell layer, with a basal lamina which contributes to the blood-thymus barrier. From the 9th gestational week, prethymic precursor cells from hemopoietic centers, begin to invade the thymus anlage. There they finally mature to committed post-thymic T cells. The thymus microenvironment of postnatal thymus is composed of six different types of epithelial cells and several stromal cells of mesodermal origin. The location of these diverse stationary cells is described, and their functional significance is discussed. Obviously these stromal cell types have a special function in providing the proper environment for T-cell maturation. The function of the thymus includes the maturation and/or selection of antigen specific T-cells. The main issue of intra-thymic T-cell differentiation is the development and expression of T-cell-antigen receptors. The great diversity of these receptors is generated by a rearrangement of the T-cell-receptor-genes in order to furnish the host with a mature T-cell repertoire that is capable of recognizing the world of extrinsic antigens. In a synopsis the manyfold interrelationships between the thymus microenvironment and the developing thymocytes are summarised.Abbreviations
BALT
Bronchus Associated Lymphoid Tissue
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CD
Cluster of Differentiation
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cCD3
cytoplasmic CD3
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mCD3
membranous CD3
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C.R.
Crown Rump
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GALT
Gut Associated Lymphoid Tissue
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HLA
Human Leucocyte antigen
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HLA-DR
Gene product of the MHC-class II (this antigen is a surface molecule of numerous stationary and free cells of the immune system)
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IDC
Interdigitating Cell
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IL1
Interleukin 1 (cytokine derived mainly from makrophages, but also from other cell types)
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IL2 and IL4
Interleukin 2 and 4 (cytokines derived mainly from T-cell, but also from other cell types)
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IL4R
Interleukin 4-Receptor
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Mab
Monoclonal antibody
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MHC
Major Histocompatibility Complex
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p.c.
post conception
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TCR
T-Cell-Receptor
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TNC
Thymic Nurse Cell
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TdT
Terminal deoxynucleotidyl Transferase 相似文献
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5.
Pawar PP Jones LG Feller M Guichard JL Mujib M Ahmed MI Roy B Rahman T Aban IB Love TE White M Aronow WS Fonarow GC Ahmed A 《Archives of gerontology and geriatrics》2012,55(1):85-90
Tobacco smoking is a risk factor for atrial fibrillation (AF), but little is known about the impact of smoking in patients with AF. Of the 4060 patients with recurrent AF in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) trial, 496 (12%) reported having smoked during the past two years. Propensity scores for smoking were estimated for each of the 4060 patients using a multivariable logistic regression model and were used to assemble a matched cohort of 487 pairs of smokers and nonsmokers, who were balanced on 46 baseline characteristics. Cox and logistic regression models were used to estimate the associations of smoking with all-cause mortality and all-cause hospitalization, respectively, during over 5 years of follow-up. Matched participants had a mean age of 70 ± 9 years (± S.D.), 39% were women, and 11% were non-white. All-cause mortality occurred in 21% and 16% of matched smokers and nonsmokers, respectively (when smokers were compared with nonsmokers, hazard ratio=HR=1.35; 95% confidence interval=95%CI=1.01-1.81; p=0.046). Unadjusted, multivariable-adjusted and propensity-adjusted HR (95% CI) for all-cause mortality associated with smoking in the pre-match cohort were: 1.40 (1.13-1.72; p=0.002), 1.45 (1.16-1.81; p=0.001), and 1.39 (1.12-1.74; p=0.003), respectively. Smoking had no association with all-cause hospitalization (when smokers were compared with nonsmokers, odds ratio=OR=1.21; 95%CI=0.94-1.57, p=0.146). Among patients with AF, a recent history of smoking was associated with an increased risk of all-cause mortality, but had no association with all-cause hospitalization. 相似文献
6.
Daubländer M Kämmerer PW Willershausen B Leckel M Lauer HC Buff S Rösl B 《Clinical oral investigations》2012,16(4):1289-1295
The addition of epinephrine in dental local anaesthesia results in a longer and deeper anaesthesia under almost ischemic conditions. For short-time dental treatments, epinephrine-reduced anaesthetics may offer shorter and more individual anaesthesia with reduced potential side effects. The aim of this study was a clinical evaluation of anaesthetic potency and adverse effects of an epinephrine-reduced articaine formulation in dental patients undergoing short-time routine treatment. In a prospective clinical, not interventional, study between January 2008 and February 2009, 908 patients undergoing short-time dental treatment in five medical centers were anaesthetized with 4% articaine 1:400,000 epinephrine (Ubistesin, 3M/ESPE, Seefeld, Germany). Efficacy and safety in clinical use were evaluated. A follow-up after 1 day was conducted by telephone survey. A mean amount of 1.3-ml anaesthetic solution was needed to achieve a complete or sufficient anaesthesia in 97% (n = 876) of cases. A second injection had to be done in 3.7% (n = 34) before and in 11.9% (n = 108) during treatment. Here, the second injection had to be applied after a mean of 48.6 min. The mean duration of soft tissue anaesthesia after infiltration was 146.6 min, after nerve block 187.7 min. The painful treatment took a mean of 50.2 min and the total treatment time summed up to 68.8 min. In 1.7% cases (n = 15), unwanted side effects were observed. The results indicate that a lower concentration of epinephrine in combination with the 4% articaine solution leads to a high success rate of efficacy. The clinical use of a 4% articaine 1:400,000 epinephrine solution can be stated as safe and effective in short dental routine treatments. Reconsiderations concerning limitations of indication or additional contraindications are not necessary. 相似文献
7.
The aim of the present study was to investigate the association between caries frequency and body mass index (BMI) in German
elementary school children. A total of 1,290 elementary school children (648 boys, 642 girls) were examined. The dental examination
included the determination of caries frequency (DF-T/df-t values). The medical evaluation assessed the pupils’ general health
and BMI. The study showed that 3.6% of the children were underweight, 74.8% had a normal weight, 11.9% were overweight, and
9.7% were obese. Underweight children showed natural healthy teeth in 44.7%, those with normal weight in 40.7%, whereas children
with high weight and obese children showed natural healthy teeth in 30.5% and 31.7%, respectively. A significant association
between high weight and caries frequency in the first dentition (p = 0.0067) and in the permanent dentition (p = 0.0002) could be observed. The association remains statistically significant after adjusting for age. The number of natural
healthy teeth decreased with age (p = 0.001) and BMI (p = 0.0061) and was different between girls and boys (p = 0.0334). This study demonstrated a significant association between caries frequency and weight in school children. In future
preventive programs, the importance of nutrition should not only be emphasized with respect to general diseases but also with
regard to carious lesions. 相似文献
8.
Virginia Gonzalez Kerstin Sandelin Anders Karlsson Wiveca Åberg Lars Löfgren Gabriela Iliescu Staffan Eriksson Brita Arver 《World journal of surgery》2014,38(7):1685-1693
Background
Breast magnetic resonance imaging (MRI) has shown high sensitivity in determining tumor extent, multifocality, and occult contralateral breast cancer. Low specificity, unnecessary mastectomies, and costs are arguments against MRI. The purpose of this study was to determine whether preoperative breast MRI would affect primary surgical management, reduce reexcision/reoperation procedures, and influence the choice of neoadjuvant treatment in patients with newly diagnosed breast cancer.Methods
This prospective, randomized, multicenter study included 440 breast cancer patients younger than aged 56 years from three, Swedish, large-volume breast units. Patients were randomly allocated on a 1:1 basis to either preoperative staging with breast MRI (n = 220) or no breast MRI (n = 220) (control group). Treatment planning of all patients was discussed at multidisciplinary team conferences.Results
In patients randomized to the MRI group, who had an observed higher percentage of planned breast-conserving surgery (BCS) compared with the control group, a change from suggested breast conservation to mastectomy occurred in 23 of 153 (15 %) patients. Breast MRI provided additional information in 83 of 220 (38 %) patients, which caused a change in treatment plan in 40 (18 %). The breast reoperation rate was significantly lower in the MRI group: 11 of 220 (5 %) versus 33 of 220 (15 %) in the control group (p < 0.001). The number of mastectomies, axillary reoperations, and the number of patients receiving neoadjuvant chemotherapy after definitive treatment did not differ significantly between the groups.Conclusions
Preoperative staging with breast MRI in women younger than age 56 years altered the treatment plan in 18 % of the patients. Although a higher MRI-related conversion rate from breast conservation to mastectomy was found, the final numbers of mastectomies did not differ between the two groups. The breast reoperation rate in the MRI group was significantly reduced. 相似文献9.
Gazanfer Belge Sandra Bruckmann Brita Thode Sabine Bartnitzke Jrn Bullerdiek 《Genes, chromosomes & cancer》1996,16(2):149-151
Cytogenetic studies of thyroid hyperplasias and adenomas have shown that besides cases with an apparently normal karyotype different groups of cytogenetic abnormalities exist. Herein we describe the cytogenetic analyses of two benign thyroid tumors with deletions of the short arm of chromosome 2. A similar case has been described previously. Besides the previously well-established subgroups, alterations of chromosome 2 may thus characterize a new cytogenetic subgroup of benign thyroid tumors. Genes Chromosom Cancer 16:149–151 (1996). © 1996 Wiley-Liss, Inc. 相似文献
10.
Brita Sedlmayr Martin Sedlmayr Bjrn Kroll Hans-Ulrich Prokosch Julian Gruendner Christina Schüttler 《Applied clinical informatics》2022,13(2):400
Background Within the German “Network University Medicine,” a portal is to be developed to enable researchers to query on novel coronavirus disease 2019 (COVID-19) data from university hospitals for assessing the feasibility of a clinical study. Objectives The usability of a prototype for federated feasibility queries was evaluated to identify design strengths and weaknesses and derive improvement recommendations for further development. Methods In the course of a remote usability test with the thinking-aloud method and posttask interviews, 15 clinical researchers evaluated the usability of a prototype of the Feasibility Portal. The identified usability problems were rated according to severity, and improvement recommendations were derived. Results The design of the prototype was rated as simple, intuitive, and as usable with little effort. The usability test reported a total of 26 problems, 8 of these were rated as “critical.” Usability problems and revision recommendations focus primarily on improving the visual distinguishability of selected inclusion and exclusion criteria, enabling a flexible approach to criteria linking, and enhancing the free-text search. Conclusion Improvement proposals were developed for these user problems which will guide further development and the adaptation of the portal to user needs. This is an important prerequisite for correct and efficient use in everyday clinical work in the future. Results can provide developers of similar systems with a good starting point for interface conceptualizations. The methodological approach/the developed test guideline can serve as a template for similar evaluations. 相似文献