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21.
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Calcifications can develop within the crypts of the palatine tonsil. During routine dental panoramic radiography, these tonsillar calcifications, or tonsilloliths, may be visualized superimposed upon the mandibular ramus. Their anatomic location and radiographic appearance are such that confusion with parotid sialolithiasis may occur. This report defines the symptomatology and differential diagnosis of these tonsilloliths.  相似文献   
23.
Objective: The aims of this work were to histologically examine the healing of mineralized human bone allograft (MHBA) in sinus augmentation for elevating a severe maxillary atrophy ridge (≤2 mm residual ridge height) and to correlate the results to the sinus cavity size. Material and methods: A two‐stage protocol was conducted in 23 patients, all having crestal bone ≤2 mm. A mixture of 80/20 cortical/cancellous of MHBA particles was used to augment sinus using the lateral window approach in narrow (NS; <15 mm bucco‐palatal distance) and wide (WS; ≥15 mm bucco‐palatal distance) sinuses, based upon computerized tomography (CT) assessment. A bone core biopsy was taken at implant placement, 6 and 9 months after surgery. Microradiography, histology and histochemistry of methacrylate‐embedded sections were performed to analyze and to evaluate the bone and graft amount. Results: Newly formed bone around MBHA particles was found in all 28 biopsies. Bone showed a woven structure at 6 months after surgery and a lamellar structure 9 months after surgery. At 6 months after surgery, the 13 NS and 15 WS had 30.5±8.8% and 20.7±4.9% mean±SD bone formation, respectively. At 9 months after surgery, it was 38.8±7% (NS) and 30.7±3% (WS). Residual graft was about 16% (6 months) and 6% (9 months), in both NS and WS. The Mann–Whitney test showed a greater bone formation in NS than in WS (P<0.005). Conclusions: The used 80/20 MHBA mixture appears to promote, in the severe atrophic maxilla, a satisfactory bone formation. Our results prove that the larger the sinus, the longer the maturation time needed to achieve a suitable amount of new bone formation. To cite this article:
Maria Soardi C, Spinato S, Zaffe D, Wang H‐L. Atrophic maxillary floor augmentation by mineralized human bone allograft in sinuses of different size: an histologic and histomorphometric analysis.
Clin. Oral Impl. Res. 22 , 2011; 560–566
doi: 10.1111/j.1600‐0501.2010.02034.x  相似文献   
24.
Objective. Impulsivity represents a key dimension in obsessive–compulsive disorder (OCD), in relation to outcome and course. It can be assessed through the Barratt Impulsiveness Scale (BIS), which explores three main areas: attentional, motor, and nonplanning. Present study was aimed to assess level of impulsivity in a sample of OCD patients, in comparison with healthy controls, using the BIS. Methods. Seventy-five OCD outpatients, 48 of them having psychiatric comorbidities and 70 healthy controls, were assessed through the BIS, and their scores were analyzed using Student's t-test for independent samples, on the basis of demographic and clinical characteristics. Results. BIS total scores were significantly higher (P: 0.01) in patients compared to controls, with no difference between pure and comorbid patients. Attentional impulsivity scores were significantly higher than controls in patients with pure (P < 0.001) and comorbid OCD (P < 0.001), without differences among them. Patients with multiple OC phenotypes showed higher, though statistically non significant, total and attentional scores, compared to single phenotype patients. In addition, patients with comorbid major depressive disorder had higher, though statistically non significant, total and attentional scores, compared to patients with comorbid bipolar disorder, generalized anxiety disorder, and other disorders. Conclusions. Present findings showed higher impulsivity levels in OCD patients versus controls, particularly in the attentional area, and ultimately suggest a potential cognitive implication.  相似文献   
25.
Patent foramen ovale (PFO) is a common congenital anatomical defect in the general population with a mean prevalence of 20 %. Transcranial Doppler sonography and echocardiography, both with infusion of agitated saline as an echo contrast, have been introduced for the diagnosis of PFO. Transesophageal echocardiography is considered the gold standard. Several studies have suggested an association between cryptogenetic stroke and PFO, but the role of this condition as a risk factor for stroke is still debated. The aims of this prospective multicentre study are the evaluation of PFO prevalence in the whole ischemic stroke population and the identification of a stroke recurrence profile risk in patients with PFO. All consecutive patients admitted for acute ischemic stroke and with a confirmed diagnosis at discharge are eligible cases for the study. Demographic and vascular risk factors are registered. Clinical severity is summarized by the National Institute of Health stroke scale. Echocardiographic and transcranial studies are performed in each patient to detect the presence of PFO. Prevalence of PFO will be calculated with 95 % CIs. Univariate analysis will be performed to detect the correlation of PFO with different registered factors and multivariable analysis with PFO as independent variable. The present study should contribute to better identify the role of PFO in ischemic stroke risk and recurrence-related events. Qualifying findings of the study are represented by the high number of enrolled patients, the prospective methodology of the study and the presence of secondary instrumental endpoints.  相似文献   
26.
Notwithstanding fundamental methodological advancements, scientific information about disorders of consciousness (DOCs)—e.g. Vegetative State/Unresponsive Wakefulness Syndrome (VS/UWS) and Minimally Conscious State (MCS)—is incomplete. The possibility to discriminate between different levels of consciousness in DOC states entails treatment strategies and ethical concerns. Here we attempted to investigate Italian clinicians’ and basic scientists’ opinions regarding some issues emerging from the care and the research on patients with DOCs. From our survey emerged that Italian physicians working with patients with DOCs give a central role to ethics. Current Italian regulation regarding basic research conducted in patients with DOCs apparently risks to be inadequate to support scientific advancement, and would deserve a different assessment compared to ordinary treatments. We think the results of our survey deserve attention from an international audience because they exemplify the difficulty to define a shared approach to the issues related to patients with DOCs and the necessity to better assess both the ordinary and experimental treatment of patients with DOCs at the ethical and legal level.  相似文献   
27.
After three proceedings in which neuroscience was a relevant factor for the final verdict in Italian courts, for the first time a recent case puts in question the legal relevance of neuroscientific evidence. This decision deserves international attention in its underlining that the uncertainty still affecting neuroscientific knowledge can have a significant impact on the law. It urges the consideration of such uncertainty and the development of a shared management of it.  相似文献   
28.
Coronary spasm during coronary angiography for vasculopathy in children can be prevented by the intracoronary administration of nitroglycerin. We reviewed the anesthesia and catheterization reports and charts for pediatric transplant recipients who underwent angiography from 2005 through 2010. Correlation analysis was used to study the relation of post-injection systolic blood pressure (SBP) to nitroglycerin dose. Forty-one angiographic evaluations were performed on 25 patients (13 male and 12 female). Mean age was 9.9 ± 3.2 years (range, 3.3–16.1 yr). The mean total dose of nitroglycerin was 2.93 ± 1.60 µg/kg (range, 1–8 µg/kg).There was a significant drop between the baseline SBP (mean, 106 ± 21.6 mmHg) and the lowest mean SBP before nitroglycerin administration (78 ± 13.2, P <0.0001, paired t test). There was no significant additional change in SBP (mean after nitroglycerin administration, 80.7 ± 13.1 mmHg; P = 0.2). There was a significant drop in lowest heart rate between baseline (109 ± 16.5 beats/min) and before nitroglycerin administration (89 ± 14.3 beats/min; P <0.0001, paired t test). There was no significant additional change in heart rate (mean heart rate after nitroglycerin, 84 ± 17.7 beats/min; P = 0.09). There were 2 interventions for SBP before nitroglycerin and 2 after nitroglycerin. One child experienced a transient ST-T–segment change during angiography after nitroglycerin. In the highest dose range, the additional decrease in SBP was 7.2 mmHg (P=0.03). Routine intracoronary nitroglycerin administration in this dose range produced no significant changes in SBP or heart rate in children.Key words: Child, coronary angiography, coronary vasospasm/etiology, dose-response relationship, drug, heart transplantation/adverse effects, hemodynamics/drug effects, nitroglycerin/administration & dosage/therapeutic use, postoperative complications/therapy, retrospective studies, vasodilation/drug effectsAllograft coronary disease in children occurs with increasing frequency after transplantation, as a function of time. In a multicenter study,1 the incidence of coronary artery disease in children 5 years post-transplant was 17% of all recipients. Coronary angiography remains the gold standard in the detection of vasculopathy in heart-transplant recipients.2 Coronary artery spasm can complicate selective coronary angiography and result in myocardial ischemia. Coronary spasm can simulate the angiographic appearance of graft vasculopathy and cause diagnostic confusion.3 The spasm can arise from manipulation of the arterial wall by the catheter or from intraluminal injection of contrast material. In cardiac transplant recipients, coronary artery spasm has been reported in as many as 4.9% of coronary angiograms.3In adults, intracoronary nitroglycerin is routinely administered during coronary angiography to prevent coronary artery spasm.4 In children, however, safety and dosage guidelines for intracoronary nitroglycerin have not yet been firmly established. A dose of 3 µg/kg can be extrapolated by weight from the established adult dose of 200 µg; this dose was used in a study of children after the arterial switch operation and was shown to produce coronary vasodilation—with a small reduction in systolic blood pressure (SBP) and no noteworthy change in heart rate—in a control group of patients.5,6We previously reported a case of coronary artery spasm during routine coronary angiographic monitoring in a 9-year-old boy who had undergone heart transplantation as an infant.7 After left main coronary artery injection of contrast material, the patient''s left anterior descending and left circumflex coronary arteries appeared to be diffusely narrow, and he developed marked ST-segment elevation, hypotension, and ventricular tachycardia. After cardiopulmonary resuscitation, he recovered uneventfully and displayed normal systolic function. Coronary angiography one month later, with the administration of intracoronary nitroglycerin before the injection of contrast material, revealed normal coronary artery diameter and was accomplished without complication.Since 2005, intracoronary nitroglycerin has routinely been used in pediatric transplant patients during biennial selective coronary angiographic monitoring at our institution. The purpose of the study is to report our experience with the routine use of intracoronary nitroglycerin for coronary angiography in children: its effects on blood pressure, on heart rate, and on the occurrence of arrhythmia and ST-segment elevation.  相似文献   
29.
Since the mechanisms by which specific immunity destroys Her-2/neu carcinoma cells are highly undetermined, these were assessed in BALB/c mice vaccinated with plasmids encoding extracellular and transmembrane domains of the protein product (p185(neu)) of the rat Her-2/neu oncogene shot into the skin by gene gun. Vaccinated mice rejected a lethal challenge of TUBO carcinoma cells expressing p185(neu). Depletion of CD4 T cells during immunization abolished the protection, while depletion of CD8 cells during the effector phase halved it, and depletion of polymorphonuclear granulocytes abolished all protection. By contrast, Ig mu-chain gene KO mice, as well as Fcgamma receptor I/III, beta-2 microglobulin, CD1, monocyte chemoattractant protein 1 (MCP1), IFN-gamma, and perforin gene KO mice were protected. Only mice with both IFN-gamma and perforin gene KOs were not protected. Although immunization also cured all BALB/c mice bearing established TUBO carcinomas, it did not cure any of the perforin KO or perforin and IFN-gamma KO mice. Few mice were cured that had knockouts of the gene for Ig mu-chain, Fcgamma receptor I/III, IFN-gamma, or beta-2 microglobulin. Moreover, vaccination cured half of the CD1 and the majority of the MCP1 KO mice. The eradication of established p185(neu) carcinomas involves distinct mechanisms, each endowed with a different curative potential.  相似文献   
30.
Surgery had been the traditional treatment for native coarctation of the aorta, one of the most common cardiovascular congenital malformations. As a less invasive mode of treatment, balloon angioplasty has emerged as an alternative to surgery but has not gained universal acceptance due to its rates of restenosis secondary to vessel recoil and concerns over aortic wall injury resulting in aneurysm formation. To overcome these problems, endovascular stents were introduced in the management of this condition. The early- and intermediate-term results are encouraging, with low rates of restenosis and complications. In this article, the authors review the current evidence on coarctation stenting and discuss future trends in this area.  相似文献   
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