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131.
Philip Gerretsen M. Mallar Chakravarty David Mamo Mahesh Menon Bruce G. Pollock Tarek K. Rajji Ariel Graff‐Guerrero 《Human brain mapping》2013,34(5):1035-1043
Introduction: Lack of illness awareness or anosognosia occurs in both schizophrenia and right hemisphere lesions due to stroke, dementia, and traumatic brain injury. In the latter conditions, anosognosia is thought to arise from unilateral hemispheric dysfunction or interhemispheric disequilibrium, which provides an anatomical model for exploring illness unawareness in other neuropsychiatric disorders, such as schizophrenia. Methods: Both voxel‐based morphometry using Diffeomorphic Anatomical Registration through Exponentiated Lie Algebra (DARTEL) and a deformation‐based morphology analysis of hemispheric asymmetry were performed on 52 treated schizophrenia subjects, exploring the relationship between illness awareness and gray matter volume. Analyses included age, gender, and total intracranial volume as covariates. Results: Hemispheric asymmetry analyses revealed illness unawareness was significantly associated with right < left hemisphere volumes in the anteroinferior temporal lobe (t = 4.83, P = 0.051) using DARTEL, and the dorsolateral prefrontal cortex (t = 5.80, P = 0.003) and parietal lobe (t = 4.3, P = 0.050) using the deformation‐based approach. Trend level associations were identified in the right medial prefrontal cortex (t = 4.49, P = 0.127) using DARTEL. Lack of illness awareness was also strongly associated with reduced total white matter volume (r = 0.401, P < 0.01) and illness severity (r = 0.559, P < 0.01). Conclusion: These results suggest a relationship between anosognosia and hemispheric asymmetry in schizophrenia, supporting previous volume‐based MRI studies in schizophrenia that found a relationship between illness unawareness and reduced right hemisphere gray matter volume. Functional imaging studies are required to examine the neural mechanisms contributing to these structural observations. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
132.
133.
Objective
To evaluate the open laminate technique using glass ionomer cements (GIC) in association with a low shrink composite for restoring root filled premolars.Methods
Extensive MOD cavities plus endodontic access and root filling were performed in intact extracted maxillary premolars. Three restoration types were evaluated: (1) resin composite alone; (2) resin-modified GIC (RM-GIC) open laminate plus resin composite; (3) conventional GIC open laminate plus resin composite (n = 8 for all groups and tests). Three tests were conducted to assess restorations: (A) inward cusp deflection during light curing, using DCDTs; (B) fracture strength using a ramped oblique load at 45° to the long axis in a servohydraulic testing machine in comparison with intact and unrestored teeth; (C) proximal marginal leakage using methylene blue dye and the effect of thermocycling. Data were analysed using 1-way ANOVA for cuspal deflection and fracture strength and Fisher's exact test for leakage.Results
Laminate restorations resulted in significantly less cuspal deflection compared with resin composite (4.2 ± 1.2 μm for RM-GIC and 5.1 ± 2.3 μm for conventional GIC vs. 12.2 ± 2.6 μm for composite, P < 0.001). Fracture strength was not significantly different among all groups. Failure with all restorations was predominantly adhesive at the tooth-restoration interface. The two laminate groups showed significantly better marginal seal than composite alone, but sealing ability of conventional GIC deteriorated after thermocycling.Conclusions
Laminate restoration of root filled teeth had beneficial effects in terms of reducing cuspal deflection and marginal seal, with acceptable fracture strength. 相似文献134.
Andrew B. Rosenkrantz Tarek N. Hanna Scott D. Steenburg Mary Jo Tarrant Robert S. Pyatt Eric B. Friedberg 《Journal of the American College of Radiology》2019,16(12):1677-1687
PurposeTo explore the current state of teleradiology practice, defined as the interpretation of imaging examinations at a different facility from where the examination was performed.MethodsA national survey addressing radiologists’ habits, attitudes, and perceptions regarding teleradiology was distributed by e-mail to a random sample of ACR members in early 2019.ResultsAmong 731 of 936 respondents who indicated a non-teleradiologist primary work setting, 85.6% reported performing teleradiology within the past 10 years and 25.4% reported that teleradiology represents a majority of their annual imaging volumes; 84.4% performed teleradiology for internal examinations and 45.7% for external examinations; 46.2% performed teleradiology for rural areas and 37.2% for critical access hospitals; 91.3% performed teleradiology during weekday normal business hours and 44.5% to 79.6% over evening, overnight, and weekend hours. In all, 76.9% to 86.2% perceived value from teleradiology for geographic, after-hours, and multispecialty coverage, as well as reduced interpretation turnaround times. The most common challenges for teleradiology were electronic health record access (62.8%), quality assurance (53.8%), and technologist proximity (48.4%). The strategy most commonly considered useful for improving teleradiology was technical interpretation standards (33.3%). Radiologists in smaller practices were less likely to perform teleradiology or performed teleradiology for lower fractions of work, were less likely to experience coverage advantages of teleradiology, and reported larger implementation challenges, particularly relating to electronic health records and prior examination access.ConclusionDespite historic concerns, teleradiology is widespread throughout modern radiology practice, helping practices achieve geographic, after-hours, and multispecialty coverage; reducing turnaround times; and expanding underserved access. Nonetheless, quality assurance of offsite examinations remains necessary. IT integration solutions could help smaller practices achieve teleradiology’s benefits. 相似文献
135.
Alloush Taha K. Mansour Osama Alloush Adel T. Roushdy Tamer Hamid Eman El-Shamy Mahmoud Shokri Hossam M. 《Neurological sciences》2022,43(2):799-809
Neurological Sciences - COVID-19 is a pandemic disease which predominantly affects the respiratory system with high critical care mortality and morbidity; however, it also causes multi-organ... 相似文献
136.
Tarek N. Hanna Haris Shekhani Matthew E. Zygmont James Matthew Kerchberger Jamlik-Omari Johnson 《Emergency radiology》2016,23(2):169-174
The purpose of this study was to evaluate the frequency of incidental findings (IFs) in emergency department (ED) imaging reports and evaluate the adherence of imaging recommendations to consensus societal guidelines for IFs. A retrospective review of consecutive ED computed tomography (CT) and ultrasonography (US) reports from two university-affiliated EDs over a 2-month period was performed. Each imaging report was reviewed in its entirety, and incidental findings were documented along with recommendations for additional imaging. Imaging recommendations were compared to published societal guidelines from the American College of Radiology (ACR) and Fleischner Society. Three thousand one hundred thirty-one total cases consisting of 1967 CTs and 1164 US contained 514 incidental findings (16.4 %), with 329 CT IFs (64 %) and 185 US IFs (36 %). The ovary was the most common organ for an IF (n?=?214, 42 %). Of all IFs, 347 (67.5 %) recommendations were concordant with societal guidelines and 167 (32.5 %) were discordant. 39.8 % of CT recommendations were discordant, while 19.5 % of US recommendations were discordant (p?<?0.0001). Incidental findings are commonly encountered in the emergent setting. Variable adherence to societal guidelines is noted. Targeted radiologist education and technological solutions may decrease rates of discordance. 相似文献
137.
Objective: To assess the impact of unilateral dose adjusted ovarian drilling (ULOD) compared to bilateral ovarian drilling (BLOD) on ovarian reserve and pregnancy rate.Methods: This randomized clinical study included 105 patients with polycystic ovary syndrome. Patients were assigned to two groups; group 1 (n?=?52) underwent dose adjusted ULOD using 60 Joules/cm3 applied to the larger ovary, while group 2 (n?=?53) underwent BLOD with fixed doses of 1200 J. Ovulation rate, anti-Mullerian hormone (AMH), antral follicle count (AFC), and pregnancy rates were assessed at 3 and 6 months of follow-up.Results: Ovulation and pregnancy rates at 3 months periods were comparable (p?>?0.05), but was significantly higher in BLOD at 6 months period (p?0.05). There was a highly significant difference between the two groups regarding the AMH level at 3- and 6-month follow-up periods (p?0.001) with lower levels in the BLOD group. The AFC was comparable in the two groups after 3 months (p?>?0.05) but became higher in the ULOD at 6-month follow-up period (p?0.001).Conclusion: Dose-adjusted ULOD applied to the larger ovary has comparable ovulation and pregnancy rates to fixed dose BLOD at 3-month follow-up periods with decrease in its effectiveness after 6 months. 相似文献
138.
Omar Bauomy Ahmed Usama Taha Mahmoud Sara Elganady Allam Mohamed Nafady Salah Mohamed Hassan Afifi 《Ultrastructural pathology》2016,40(6):342-350
Silver nanoparticles (SNP) are used in many pharmaceutical, cosmetic, and industrial products already available in the market. Although they are considered relatively safe, many toxic and pathological alterations in different organs including immune organs were reported after SNP administration. In this study, 10-week-old male mice (n = 20) were divided into two groups. Ten mice received greenly synthesized gelatin-coated silver nanoparticles in a dose of 10 mg/kg body weight for five consecutive days while the other 10 received 0.5 ml of distilled water daily for 5 days and kept as control. At the sixth day, all mice were sacrificed; blood and tissue samples were collected and prepared for pathological analysis. Liver and kidney lesions were in the form of degenerative and inflammatory changes. Interestingly, the immune organs were drastically affected by SNP treatment. Severe hyperplasia of the Peyer’s patches was noticed in the intestines of intoxicated animals both in gross and microscopic examination. Spleen was enlarged and showed large number of megakaryocytes. The particles were encountered in membrane-bound phagosomes inside macrophages in different organs like lungs and spleen. Blood picture complied to morphological findings with an increase in monocytes and eosinophils accompanied by drop in the platelets count in the intoxicated animals. 相似文献
139.
Femoral arterial cannulation performed by residents: a comparison between ultrasound‐guided and palpation technique in infants and children undergoing cardiac surgery 下载免费PDF全文
140.
Zarantonelli ML Szatanik M Giorgini D Hong E Huerre M Guillou F Alonso JM Taha MK 《Infection and immunity》2007,75(12):5609-5614
The pathogenesis of meningococcal disease is poorly understood due to the lack of a relevant animal model. Moreover, the use of animal models is not optimal as most meningococcal virulence determinants recognize receptors that are specifically expressed in human tissues. One major element of the host specificity is the system of meningococcal iron uptake by transferrin-binding proteins that bind specifically human transferrin but not murine transferrin. We developed a new mouse model for experimental meningococcal infection using transgenic mice expressing human transferrin. Intraperitoneal challenge of transgenic mice induced bacteremia for at least 48 h with an early stage of multiplication, whereas the initial inoculum was rapidly cleared from blood in wild-type mice. Inflammation in the subarachnoidal space with a high influx of polymorphonuclear cells was observed only in transgenic mice. Meningococcal mutants that were unable to use transferrin as a source of iron were rapidly cleared from both wild-type and transgenic mice. Thus, transgenic mice expressing human transferrin may represent an important advance as a new mouse model for in vivo studies of meningococcal virulence and immunogenicity factors. 相似文献