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41.
PURPOSE: This study was performed to retrospectively evaluate treatment of deep caries in primary molars with formocresol pulpotomy (FP) and indirect pulp therapy (IPT). METHODS: 133 primary molars with deep caries approaching the pulp were treated with FP (N = 78) or IPT (N = 55) and followed 2-7 years. All IPTs received immediate stainless steel crowns (SSCs); 61 FPs got an immediate SSC, 13 an intermediate restorative material (IRM), and 4 amalgam. Thirteen IPTs and 25 FPs had pre-operative pain compatible with a diagnosis of reversible pulpitis. Treatment notes and radiographs were independently assessed. RESULTS: Overall IPT success was 93% (51/55) versus 74% (58/78) for FP. Molars with pain compatible with a diagnosis of reversible pulpitis were successfully treated by IPT 85% (11/13) versus 76% (19/25) for FP. FP-treated molars exhibited earlier exfoliation 38% (30/78), while all IPT molars exhibited normal exfoliation. FPs receiving immediate SSCs had 50/61 (82%) succeed; FPs restored with an IRM temporary succeeded 5/13 (39%), amalgam 3/4 (75%). CONCLUSIONS: IPT success was significantly higher than FP (P = 0.01) in the treatment of deep caries. Both IPT and FP were successful in treating teeth with pain compatible with the diagnosis of reversible pulpitis. FP significantly hastened the exfoliation of pulpotomized primary molars (P = 0.001). IPT in primary teeth can be successfully used in a one step procedure. SSCs placed immediately after FP significantly increased FP success vs. FP followed by IRM temporary (P = 0.01).  相似文献   
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ObjectiveTo compare the attitudes of preclinical and clinical dental students toward their own oral health using the Hiroshima University-Dental Behavioral Inventory (HU-DBI).MethodsThe English-language version of the 20-item HU-DBI was distributed to all preclinical and clinical students at the College of Dentistry, University of Dammam, Kingdom of Saudi Arabia. Dichotomized (agree/disagree) responses to 12 HU-DBI items were used in this study, with a maximum possible score of 12. Responses to the remaining eight statements reflected general oral health attitudes and were excluded from the analysis. Data were analyzed statistically.ResultsThe overall response rate was 72.2% (preclinical, 72.5%; clinical, 72%). The mean HU-DBI score was significantly higher among clinical than among preclinical dental students (7 vs. 5.8; P < 0.05). Higher proportions of preclinical than clinical students did not worry about visiting the dentist but postponed dental visits until they experienced toothache. Furthermore, more preclinical than clinical students reported that their gums bled upon brushing, used a child-sized toothbrush, had observed white, sticky deposits on their teeth, and used strong strokes for toothbrushing. More clinical than preclinical students reported that they did not feel that the condition of their teeth was worsening despite brushing, worried about the color of their teeth, brushed each of their teeth carefully, and checked their teeth in the mirror after brushing.ConclusionsDental health awareness programs should be implemented and information about positive oral health attitudes should be provided to the students at an initial stage of dental training.  相似文献   
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In this study, we tested whether the human heart possesses a cardiac stem cell (CSC) pool that promotes regeneration after infarction. For this purpose, CSC growth and senescence were measured in 20 hearts with acute infarcts, 20 hearts with end-stage postinfarction cardiomyopathy, and 12 control hearts. CSC number increased markedly in acute and, to a lesser extent, in chronic infarcts. CSC growth correlated with the increase in telomerase-competent dividing CSCs from 1.5% in controls to 28% in acute infarcts and 14% in chronic infarcts. The CSC mitotic index increased 29-fold in acute and 14-fold in chronic infarcts. CSCs committed to the myocyte, smooth muscle, and endothelial cell lineages increased approximately 85-fold in acute infarcts and approximately 25-fold in chronic infarcts. However, p16(INK4a)-p53-positive senescent CSCs also increased and were 10%, 18%, and 40% in controls, acute infarcts, and chronic infarcts, respectively. Old CSCs had short telomeres and apoptosis involved 0.3%, 3.8%, and 9.6% of CSCs in controls, acute infarcts, and chronic infarcts, respectively. These variables reduced the number of functionally competent CSCs from approximately 26,000/cm3 of viable myocardium in acute to approximately 7,000/cm3 in chronic infarcts, respectively. In seven acute infarcts, foci of spontaneous myocardial regeneration that did not involve cell fusion were identified. In conclusion, the human heart possesses a CSC compartment, and CSC activation occurs in response to ischemic injury. The loss of functionally competent CSCs in chronic ischemic cardiomyopathy may underlie the progressive functional deterioration and the onset of terminal failure.  相似文献   
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A simple, efficient, cost-effective, recyclable and green approach has been developed for the synthesis of new dihydropyrimidinone analogs via the Biginelli reaction. The methodology involves a multicomponent reaction catalyzed by “HPA-Montmorillonite-KSF” as a reusable and heterogeneous catalyst. This method gives an efficient and much improved modification of the original Biginelli reaction, in terms of yield and short reaction times under solvent free conditions. All the derivatives were subjected to cytotoxicity screening against a panel of four different human cancer cell lines viz. colon (Colo-205), prostate (PC-3), leukemia (THP-1) and lung (A549) to check their effect on percentage growth. MTT [3-(4,5-dimethylthiazol-yl)-diphenyl tetrazoliumbromide] cytotoxicity assay was employed to check IC50 values. Of the synthesized analogs, 16a showed the best activity with IC50 of 7.1 ± 0.8, 13.1 ± 1.4, 13.8 ± 0.9 and 14.7 ± 1.1 μM against lung (A549), leukemia (THP-1), prostate (PC-3) and colon (Colo-205) cancer lines, respectively. The 16a analog was further checked for its effect on cancer cell properties through clonogenic (colony formation) and scratch motility (wound healing) assays and thereby was found that it reduced both the colony formation and migratory properties of the lung cancer cell line (A549). Further, molecular docking studies were performed with 16a to show its binding mode.

The general method for the preparation of DHPM analogs; cytotoxic activity and binding mode of the most active derivative against PI3Kγ and CDK2 targets.  相似文献   
46.
Zinc sulfide (ZnS) thin films with variable structural, optical, electrical, and thermoelectric properties were obtained by changing the source-to-substrate (SSD) distance in the physical-vapor-thermal-coating (PVTC) system. The films crystallized into a zinc-blende cubic structure with (111) preferred orientation. The films had a wide 3.54 eV optical band gap. High-quality homogenous thin films were obtained at 60 mm SSD. The sheet resistance and resistivity of the films decreased from 1011 to 1010 Ω/Sq. and from 106 to 105 Ω-cm, when SSD was increased from 20 mm to 60 mm, respectively. The phase and band gap were also verified by first principles that were in agreement with the experimental results. Thermoelectric characteristics were studied by using the semi-classical Boltzmann transport theory. The high quality, wide band gap, and reduced electrical resistance make ZnS a suitable candidate for the window layer in solar cells.  相似文献   
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Serial intravascular ultrasound virtual histology (IVUS-VH) after implantation of metallic stents has been unable to show any changes in the composition of the scaffolded plaque overtime. The everolimus-eluting ABSORB scaffold potentially allows for the formation of new fibrotic tissue on the scaffolded coronary plaque during bioresorption. We examined the 12?month IVUS-VH changes in composition of the plaque behind the struts (PBS) following the implantation of the ABSORB scaffold. Using IVUS-VH and dedicated software, the composition of the PBS was analyzed in all patients from the ABSORB Cohort B2 trial, who were imaged with a commercially available IVUS-VH console (s5i system, Volcano Corporation, Rancho Cordova, CA, USA), immediately post-ABSORB implantation and at 12?month follow-up. Paired IVUS-VH data, recorded with s5i system, were available in 17 patients (18 lesions). The analysis demonstrated an increase in mean PBS area (2.39?±?1.85?mm(2) vs. 2.76?±?1.79?mm(2), P?=?0.078) and a reduction in the mean lumen area (6.37?±?0.90?mm(2) vs. 5.98?±?0.97?mm(2), P?=?0.006). Conversely, a significant decrease of 16 and 30% in necrotic core (NC) and dense calcium (DC) content, respectively, were evident (median % NC from 43.24 to 36.06%, P?=?0.016; median % DC from 20.28 to 11.36%, P?=?0.002). Serial IVUS-VH analyses of plaque located behind the ABSORB struts at 12-month demonstrated an increase in plaque area with a decrease in its NC and DC content. Larger studies are required to investigate the clinical impact of these findings.  相似文献   
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Sustained ventricular tachycardia and ventricular fibrillation (VF) are life-threatening arrhythmias which remain highly prevalent in patients with advanced heart failure. These ventricular arrhythmias may impair the support provided by continuous-flow left ventricular assist devices (CF-LVADs) and lead to frequent hospitalizations, antiarrhythmic medication use, external defibrillations, and need for heart transplantation. We report a case in which a patient with a CF-LVAD and an implantable cardioverter defibrillator at end of life presented with asymptomatic low-flow alarms and was found to have VF of unknown duration. Unique in our case was the presence of apparent organized contractility and rhythmic opening of the mitral valve on echocardiogram despite VF on electrocardiogram.  相似文献   
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