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61.
Permanent hypoparathyroidism is a severe clinical condition accompanied by low parathyroid hormone level. Conventional treatment requires lifelong medication, and daily drug usage has some side effects. To avoid this circumstance, transplantation is an alternative and curative option. Microencapsulation may be used as a transplantation approach particularly to evade immune response. In order to define treatment of permanent hypoparathyroidism, a 37‐year‐old female recipient who has permanent hypoparathyroidism was evaluated for 3 years. Routine tests, viral markers, and T and B lymphocyte cross‐match tests were analyzed. In addition intradermal skin test was performed for ultrapure alginate. Microencapsulation of cultured parathyroid cells was performed with ultrapure alginate. Cell suspension was prepared and spheroids were generated with calcium chloride. Afterward, transplantation was performed with a laparoscopic approach in the omental tissue. The recipient was discharged from the hospital without complications. Serum calcium, parathyroid hormone (PTH), and phosphorus levels were observed throughout 1 year. During the follow‐up period, no complications were observed. Serum calcium levels were increased significantly on day 10 and PTH levels were increased on day 25 as well. According to our knowledge, this is the first study where ultrapure alginate‐based microencapsulated parathyroid cells were transplanted in the omental tissue. A significant increment of PTH levels was detected. Microencapsulated parathyroid cells showed the functionality of this technique for more than 1 year. This study showed that using ultrapure alginate‐based microencapsulation without immunosuppression appears to be a promising technique.  相似文献   
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Composite tissue allografts (CTAs) are currently accepted in the clinic; however, long-term immunosuppression is still needed for allograft survival. The presence of donor-specific chimerism may induce tolerance. Thirty-six vascularized bone marrow transplantation (VBMT) allotransplantation were performed across MHC barrier under short-term protocol of 7-day alphabeta-TCRmAb and Cyclosporin A therapy to determine the efficacy of VBMT alone and VBMT augmented with donor bone marrow transplantation (BMT) in chimerism induction. Flow cytometry analysis revealed that VBMT supported with donor BMT directly into the bone resulted in chimerism augmentation and maintenance compared to VBMT. In vivo and in vitro tolerance testing showed prolonged survival of donor skin graft up to 35 days and moderate reactivity in MLR assay that suggests only tolerance induction. Transplantation of vascularized bone without chronic immunosuppression provides a substantial source of bone marrow cells, leading to the development of stable donor-specific chimerism.  相似文献   
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This case report describes the prosthodontic treatment for a 28-year-old man and a 16-year-old boy diagnosed with amelogenesis imperfecta. The aim of treatment was to reduce dental sensitivity and to restore esthetics and masticatory function. Because of the socioeconomic status of the patients, direct resin composite laminate veneers were used to improve the esthetics of their maxillary and mandibular anterior teeth. Clinical examination 12 months after treatment revealed no evidence of disorders associated with the restored teeth or their supporting structures. Definitive treatment outcomes in terms of function and esthetics satisfied the expectations of both the patient and the interdisciplinary team.  相似文献   
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Recent evidence indicates experience-dependent brain volume changes in humans, but the functional and histological nature of such changes is unknown. Here, we report that adult men performing a cognitively demanding spatial navigation task every other day over 4 months display increases in hippocampal N-acetylaspartate (NAA) as measured with magnetic resonance spectroscopy. Unlike measures of brain volume, changes in NAA are sensitive to metabolic and functional aspects of neural and glia tissue and unlikely to reflect changes in microvasculature. Training-induced changes in NAA were, however, absent in carriers of the Met substitution in the brain-derived neurotrophic factor (BDNF) gene, which is known to reduce activity-dependent secretion of BDNF. Among BDNF Val homozygotes, increases in NAA were strongly related to the degree of practice-related improvement in navigation performance and normalized to pretraining levels 4 months after the last training session. We conclude that changes in demands on spatial navigation can alter hippocampal NAA concentrations, confirming epidemiological studies suggesting that mental experience may have direct effects on neural integrity and cognitive performance. BDNF genotype moderates these plastic changes, in line with the contention that gene-context interactions shape the ontogeny of complex phenotypes.  相似文献   
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The purpose of the study was to determine if the irradiation of enamel with laser of different output powers might be viable alternatives to acid etching for the bonding of resin luting agents. Seventy-seven maxillary central incisors, extracted for periodontal reasons, were used. The enamel was etched with an erbium, chromium:yttrium–scandium–gallium–garnet (Er,Cr:YSGG) laser operated at one of six power outputs (0.5 W, 0.75 W, 1 W, 1.5 W, 1.75 W and 2 W) or with 38% phosphoric acid. Seventy teeth were used for the bond strength experiments, and the remaining seven (one specimen for each group) were used for scanning electron microscopy (SEM) to determine the topography and morphology of the treated enamel surface. The acid-etched group yielded the highest mean of shear bond strength (13.5 ± 2.8 MPa). The means of the shear bond strength for the teeth irradiated at 0.5 W, 0.75 W, 1 W, 1.5 W , 1.75 W and 2 W laser were 3.28 ± 2.4 MPa, 5.44 ± 3.4 MPa, 8.8 ± 4.5 MPa, 10.2 ± 4.0 MPa, 11.4 ± 4.8 MPa and 11.9 ± 4.3 MPa, respectively. Laser irradiation at 1.5 W, 1.75 W and 2 W produced a type III acid-etched pattern similar to that produced by acid etching. No significant enamel surface etching was obtained by 0.5 W or 0.75 W laser irradiation. Irradiation at 0.5 W and 0.75 W produced a type V acid-etched pattern. We concluded that the mean shear bond strength and enamel surface etching obtained with Er,Cr:YSGG laser (operated at 1.5 W and 1.75 W for 15 s) is comparable to that obtained with acid etching.  相似文献   
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Abstract Background: This study was undertaken to identify the incremental risk factors for early mortality in operations for proximal aortic pathologies. Methods: Between September 2000 and May 2010, 240 consecutive patients underwent replacement of various portions of the proximal aorta. Mean age was 56 ± 13 years (range 18 to 84) and female/male ratio was 3/7. Operations were performed emergently in 97, urgently in 21, and electively in 122 patients. Thirty‐four patients had previous cardiac or aortic operations. Etiology was acute dissection in 102, chronic dissection in 41, degenerative aneurysm in 61, and other factors (endocarditis, pseudoaneurysm, aortitis, etc.) in 36 patients. The ascending aorta was replaced in all patients. In addition, the aortic arch was replaced in 20 and the root was replaced in 106 patients. Results: The in‐hospital mortality rate was 10.4% in the overall group (25/240), 21.6% in emergent cases (21/97), 9.5% in urgent cases (2/21), and 1.6% in elective cases (2/122). Morbidity rates were as follows: stroke 2.7%, temporary neurological dysfunction 13.3%, nonoliguric renal failure 3%, dialysis 5.4%, tracheostomy 3.3%, bleeding requiring revision 3.3%. In multivariate analysis, the presence of malperfusion in patients with acute aortic dissection emerged as the incremental risk factor for mortality (p < 0.0001, odds ratio = 10.37). There was no variable associated with stroke. Emergency/urgency of operation did not emerge as incremental risk factors for mortality. Conclusion: Immediate outcomes of elective aortic operations for proximal aortic pathologies are excellent. Complicated acute dissections with malperfusion remain the major cause of early mortality. (J Card Surg 2011;26:393‐396)  相似文献   
70.
Recent studies in humans and animals raise the possibility that actively maintaining a detailed memory of a scene within working memory may require the hippocampus, a brain structure better known for its role in long-term memory. We show that the hippocampus is behaviorally and functionally critical for configural-relational (CR) maintenance by orchestrating the synchrony of occipital and temporal brain regions in the theta-frequency range. Using magnetoencephalography in healthy adults and patients with bilateral hippocampal sclerosis, we distinguish this hippocampus-dependent theta-network from one that is independent of the hippocampus and used for non-CR scene maintenance. This non-CR theta-network involved frontal and parietal brain regions. We also show that the functional and topographical dissociation between these two networks cannot be accounted for by perceptual difficulty or the amount of information to be maintained (“load”). Also, we confirm in healthy adults that active maintenance of the CR arrangement of objects within a scene is impaired by task-interference during the delay in a manner akin to working-memory maintenance processes. Together, these findings demand reconsideration of the classical functional-anatomical distinctions between long- and short-term memory.  相似文献   
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