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Influence of posts and cores on light transmission through different all-ceramic crowns: spectrophotometric and clinical evaluation 总被引:7,自引:0,他引:7
Carossa S Lombardo S Pera P Corsalini M Rastello ML Preti PG 《The International journal of prosthodontics》2001,14(1):9-14
PURPOSE: The influence of different types of posts and cores on light transmission through all-ceramic crowns was assessed by spectrophotometric analysis and clinical evaluation. MATERIALS AND METHODS: Three extracted natural teeth were replicated in acrylic resin, with roots prepared to receive standardized posts and cores. Using a silicone impression material as a template, various prosthodontic reconstructions were obtained by combining four types of posts and cores (polished and matte-finished gold alloy, all-ceramic, and ceramized metal alloy) and three types of all-ceramic crowns (IPS-Empress 2 surface-colored, IPS-Empress 2 stratified, and In-Ceram). The spectrophotometric analysis was performed in the dark at 25 degrees C. The teeth were backlit with an incandescent lamp at the color temperature of A illuminant and shielded to avoid spurious light entering the spectrophotometer. The transmitted light was analyzed in terms of luminance at four points of the sample surface (cervical, middle, incisal, and proximal). Twelve measurements were performed for the natural teeth, and 144 were performed for the artificial teeth. RESULTS: Natural teeth had the highest luminance. Among all-ceramic crowns, surface-colored IPS-Empress 2 had the highest luminance, and stratified IPS-Empress 2 had the lowest. Regarding posts and cores, the luminance was highest with the all ceramic, lower with the ceramized and the polished gold alloy (which had very similar luminance), and lowest with the matte-finished gold alloy. No significant difference among prosthodontic combinations was detected under clinical observation. CONCLUSION: The surface-colored glass ceramic (IPS-Empress 2) was the most translucent crown. At the standard crown thickness used, there were small, significant spectrophotometric, but not clinical, differences among the combinations tested. These findings show no esthetic contraindications for the use of polished gold alloy posts and cores with all-ceramic crowns. 相似文献
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Fibroblast growth factor 2 decreases bleomycin‐induced pulmonary fibrosis and inhibits fibroblast collagen production and myofibroblast differentiation 下载免费PDF全文
Hyun Young Koo Lamis MF El‐Baz StaceyL House Sarah N Cilvik Samuel J Dorry Nahla M Shoukry Mohamed L Salem Hani S Hafez Nickolai O Dulin David M Ornitz Robert D Guzy 《The Journal of pathology》2018,246(1):54-66
Fibroblast growth factor (FGF) signaling has been implicated in the pathogenesis of pulmonary fibrosis. Mice lacking FGF2 have increased mortality and impaired epithelial recovery after bleomycin exposure, supporting a protective or reparative function following lung injury. To determine whether FGF2 overexpression reduces bleomycin‐induced injury, we developed an inducible genetic system to express FGF2 in type II pneumocytes. Double‐transgenic (DTG) mice with doxycycline‐inducible overexpression of human FGF2 (SPC‐rtTA;TRE‐hFGF2) or single‐transgenic controls were administered intratracheal bleomycin and fed doxycycline chow, starting at either day 0 or day 7. In addition, wild‐type mice received intratracheal or intravenous recombinant FGF2, starting at the time of bleomycin treatment. Compared to controls, doxycycline‐induced DTG mice had decreased pulmonary fibrosis 21 days after bleomycin, as assessed by gene expression and histology. This beneficial effect was seen when FGF2 overexpression was induced at day 0 or day 7 after bleomycin. FGF2 overexpression did not alter epithelial gene expression, bronchoalveolar lavage cellularity or total protein. In vitro studies using primary mouse and human lung fibroblasts showed that FGF2 strongly inhibited baseline and TGFβ1‐induced expression of alpha smooth muscle actin (αSMA), collagen, and connective tissue growth factor. While FGF2 did not suppress phosphorylation of Smad2 or Smad‐dependent gene expression, FGF2 inhibited TGFβ1‐induced stress fiber formation and serum response factor‐dependent gene expression. FGF2 inhibition of stress fiber formation and αSMA requires FGF receptor 1 (FGFR1) and downstream MEK/ERK, but not AKT signaling. In summary, overexpression of FGF2 protects against bleomycin‐induced pulmonary fibrosis in vivo and reverses TGFβ1‐induced collagen and αSMA expression and stress fiber formation in lung fibroblasts in vitro, without affecting either inflammation or epithelial gene expression. Our results suggest that in the lung, FGF2 is antifibrotic in part through decreased collagen expression and fibroblast to myofibroblast differentiation. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
5.
Integration of Ultrasound in Undergraduate Medical Education at the California Medical Schools 下载免费PDF全文
Alan T. Chiem MD MPH Zachary Soucy DO Vi Am Dinh MD Mikaela Chilstrom MD Laleh Gharahbaghian MD Virag Shah MD Anthony Medak MD Arun Nagdev MD Timothy Jang MD Elena Stark MD PhD Aliasgher Hussain MD Viveta Lobo MD Abraham Pera DO J. Christian Fox MD 《Journal of ultrasound in medicine》2016,35(2):221-233
Since the first medical student ultrasound electives became available more than a decade ago, ultrasound in undergraduate medical education has gained increasing popularity. More than a dozen medical schools have fully integrated ultrasound education in their curricula, with several dozen more institutions planning to follow suit. Starting in June 2012, a working group of emergency ultrasound faculty at the California medical schools began to meet to discuss barriers as well as innovative approaches to implementing ultrasound education in undergraduate medical education. It became clear that an ongoing collaborative could be formed to discuss barriers, exchange ideas, and lend support for this initiative. The group, termed Ultrasound in Medical Education, California (UMeCali), was formed with 2 main goals: to exchange ideas and resources in facilitating ultrasound education and to develop a white paper to discuss our experiences. Five common themes integral to successful ultrasound education in undergraduate medical education are discussed in this article: (1) initiating an ultrasound education program; (2) the role of medical student involvement; (3) integration of ultrasound in the preclinical years; (4) developing longitudinal ultrasound education; and (5) addressing competency. 相似文献
6.
Elena Mazzone PT Jacqueline Montes PT MA Marion Main MA Anna Mayhew PT PhD Danielle Ramsey PT Allan M. Glanzman PT DPT Sally Dunaway PT DPT Rachel Salazar PT Amy Pasternak PT Janet Quigley PT Marika Pane MD PhD Maria C. Pera MD Mariacristina Scoto MD Sonia Messina MD PhD Maria Sframeli MD Adele D'amico MD PhD Marleen Van Den Hauwe PT Serena Sivo MD Nathalie Goemans MD Basil T. Darras MD Petra Kaufmann MD MSc Enrico Bertini MD Darryl C. De Vivo MD Francesco Muntoni MD Richard Finkel MD Eugenio Mercuri MD PhD 《Muscle & nerve》2015,52(3):435-437
Introduction: A recent Rasch analysis performed on the Hammersmith Functional Motor Scale—Expanded (HFMSE) in patients with spinal muscular atrophy (SMA) identified issues impacting scale validity, redundant items, and disordered thresholds on some items. Methods: We modified the HMFSE scoring based on the Rasch analysis and on expert consensus to establish whether the traditional scoring overestimated the number of patients with changes within 2 points from baseline. Data were collected retrospectively from multicenter data sets in 255 type 2 and 3 SMA patients. Results: The mean 12‐month changes using the new and the traditional scoring system did not differ significantly (P > 0.05). The numbers of patients who improved or decreased by >2 points were also similar. Conclusions: The presence of outliers using the traditional scoring system was not due to overestimation of changes in activities that were tested bilaterally or to discrepancies in the scoring hierarchy of individual items. Muscle Nerve 52:435–437, 2015 相似文献
7.
Del Percio C Le Pera D Arendt-Nielsen L Babiloni C Brancucci A Chen AC De Armas L Miliucci R Restuccia D Valeriani M Rossini PM 《NeuroImage》2006,31(3):1268-1277
Previous electroencephalographic (EEG) evidence has shown event-related desynchronization (ERD) of alpha rhythms before predictable painful stimuli, as a possible neural concomitant of attentional preparatory processes (Babiloni, C., Brancucci, A., Babiloni, F., Capotosto, P., Carducci, F., Cincotti, F., Arendt-Nielsen, L., Chen, A.C., Rossini, P.M., 2003. Anticipatory cortical responses during the expectancy of a predictable painful stimulation. A high-resolution electroencephalography study. Eur. J. Neurosci. 18 (6) 1692-700). This study tested the hypothesis that alpha ERD before predictable painful stimuli is reduced as an effect of distraction. A visual warning stimulus preceded a laser painful stimulation, which was strictly followed by visual imperative stimuli. In the Pain (control) condition, no task was required after the imperative stimuli. In the Pain + Movement condition, subjects had to perform a movement of the right index finger. In the Pain + Cognition condition, they had to mentally perform an arithmetical task. EEG data were recorded in 10 subjects from 30 electrodes. Artifact-free recordings were spatially enhanced by surface Laplacian transformation. Alpha ERD was computed at three alpha sub-bands according to subjects' individual alpha frequency peak (i.e., about 6-8 Hz, 8-10 Hz, 10-12 Hz). Compared to the control condition, the subjects reported a significantly lower stimulus intensity perception and unpleasantness in the Pain + Movement and Pain + Cognition conditions. In addition, there was a cancellation of the alpha 3 ERD (i.e., about 10-12 Hz) in Pain + Cognition condition and even a generation of a statistically significant alpha 3 ERS in Pain + Movement condition. These effects were maximum over fronto-central midline. These results suggest that distraction during the expectancy of pain is related to a reduced neural desynchronization of fronto-central midline alpha rhythms (i.e., reduced cortical activation) towards an overt hyper-synchronization (cortical idling). 相似文献
8.
José Antonio Pereira Miguel Pera Manuel López-Cano Marta Pascual Sandra Alonso Silvia Salvans Marta Jiménez-Toscano Alba González-Martín Luis Grande-Posa 《Cirugía espa?ola》2019,97(1):20-26
Objectives
To determine the incidence of incisional hernia (IH) in the extraction incision (EI) in colorectal resection for cancer. To analyze whether the location of the incision has any relationship with the incidence of hernias and whether mesh could be useful for prevention in high-risk patients.Methods
Retrospective review of the colon and rectal surgery database from January 2015 to December 2016. Data were classified into 2 groups, transverse (TI) and midline incision (MI), and the latter was divided into 2 subgroups (mesh [MIM] and suture [MIS]). Patients were classified using the HERNIAscore. Hernias were diagnosed by clinical and/or CT examination.Results
A total of 182 out of 210 surgical patients were included. After a median follow-up of 13.0 months, 39 IH (21.9%) were detected, 23 of which (13.4%) were in the EI; their frequency was lower in the TI group (3.4%) and in the MIM group (5.9%) than in the MIS group (29.5%; p = 0.007). The probability of developing IH in the MIS group showed an OR = 11.7 (95%CI: 3.3-42.0) compared to the TI group and 4.3 (IC 95%: 1.1-16.3) versus the MIM group.Conclusions
The location of the incision is relevant to avoid incisional hernias. Transverse incisions should be used as the first option. When a midline incision is needed, a prophylactic mesh could be considered in high risk patients because it is safe and associated with low morbidity. 相似文献9.
Nemesio Moreno Guillem Pera Manolo Medina Rosa Morral Clara Pareja 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2021,53(1):67-72
AimTo determine which variables determine the average annual attendance time per patient in Primary Care (PC) in Catalonia to improve the adequacy of the budget allocation.DesignCross-sectional ecological study.SettingThe Primary Care health centers (EAP) from the Institut Català de la Salut (ICS) in 2016.ParticipantsThe 285 EAPs from the ICS, which cover 75% of citizens over 14 years of age in Catalonia.Main measurementsAnnual average time of visits by a family doctor per patient for each EAP. It was studied how this time depended on potential explanatory variables, at the EAP level, using linear regression models.Resultsthe average visit time per patient/year was 49 minutes, varying between 23-87 minutes according to EAP. The EAPs with older population, more comorbidity, more home care, worse socioeconomic index, greater number of young pensioners and greater dispersion had more visiting time, while the EAPs with more population and more women expended less time to visit. These variables explained 64% of the visit time variability.ConclusionsThe budget allocation in PC can be based on a model that incorporates the main determinants of patient’ frequentation and adapts to their real needs. It would be necessary to deepen those factors that depend on the professional or health organizations to finish finding an optimal model of resource allocation in the PC. 相似文献
10.
Gastric and masticatory performances in full‐arch immediate loading rehabilitated patients 下载免费PDF全文
P. Pesce M. Menini M. Furnari F. Pera T. Tealdo P. Pera 《Journal of oral rehabilitation》2015,42(9):663-669
Full‐arch immediate loading implant rehabilitations provide patients with compromised dentition an effective treatment to improve their aesthetic and function. Aim of this prospective cohort study was to investigate the correlation between masticatory ability and gastric emptying rates among these patients. Ten subjects (five men and five women) with compromised dentition were tested in two occasions: before treatment and 30 days after the immediate loading rehabilitation. Masticatory ability was evaluated using the sieves test, and the gastric half emptying time (T1/2) was assessed by means of the 13C‐octanoic acid breath test. A statistically significant increment (P < 0·005) in masticatory ability was found only in reference to the particles smaller than or equal to 4·75 mm, whereas the gastric emptying rate showed a statistically significant reduction between pre‐ and post‐treatment (P = 0·003). A moderate negative correlation (rho = 0·64, P = 0·048) between the percentage change in masticatory ability and the percentage change in gastric emptying rate was evidenced. Patients with compromised dentition rehabilitated with full‐arch immediate implant prostheses present a significant improvement of the gastric process. 相似文献