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Lipoblastoma is a relatively rare tumor that occurs in infancy and early childhood and arises from embryonic white fat. Although a benign tumor, lipoblastomas tend to recur and may resemble myxoid liposarcoma. The authors report 26 cases over a 15-year period at Texas Children's Hospital. There was a slight female predilection (14F:12M). The most common symptom was a painless mass with or without increasing size. The trunk, extremities, head and neck, retroperitoneum, inguinal canal, peritoneal cavity, and lung were the tumor sites. Most tumors were circumscribed lipoblastomas and the minority were diffuse infiltrative lipoblastomatosis. Reexcision for residual or recurrent tumor was necessary more frequently in patients with lipoblastomatosis. Histopathologic examination and ultrastructural examination revealed cellular neoplasms composed of immature adipocytes with relatively well-defined septa, frequent lipoblasts, a fine vascular network, and often a myxoid appearance resembling myxoid liposarcoma. Cytogenetics was performed in 4 cases with chromosome 8q abnormality being most common. The major concern with lipoblastoma in children is to completely excise the tumor to avoid leaving residual tumor and to prevent recurrences. Confusion with myxoid liposarcoma, well-differentiated liposarcoma, and typical lipomas may occur. Although asymptomatic, lipoblastomas may cause dysfunction of other organ systems due to mass effect. Complete surgical excision with at least 2 years of follow-up is the preferred therapy.  相似文献   
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Kniest dysplasia is an autosomal-dominant chondrodysplastic condition characterized by disproportionate dwarfism, short trunk, small pelvis, kyphoscoliosis, short limbs, prominent joints, premature osteoarthritis, and craniofacial manifestations. The craniofacial abnormalities include tracheomalacia, midface hypoplasia, cleft palate, early onset myopia, retinal detachment, prominent eyes, and sensorineural hearing loss. Radiologic features include dumbbell-shaped femora, platyspondylia with anterior wedging of vertebral bodies, coronal clefts of thoracolumbar vertebral bodies, low broad ilia, and short tubular bones with broad metaphyses and deformed large epiphyses. This form of chondrodysplasia is associated with mutations in type II collagen splicing sequences. Mutations have been identified in the COL2A1 (type II collagen) gene between exons 12 and 24. Type II collagen is the predominant structural protein in cartilage, and mutations in this collagen account for the Kniest dysplasia phenotype. Histopathologic and ultrastructural features of epiphyseal plate cartilage have been described, but tracheal cartilage in an affected neonate has not been examined. The authors report the histopathologic and ultrastructural findings of anterior tracheal cartilage from a 35-day-old female with suspected chondrodysplasia who had tracheomalacia with airway obstruction. The tracheal cartilage was moderately cellular, but lacked cystic and myxoid changes in its matrix. The chondrocytes had abundant cytoplasmic PAS-positive inclusions. Some of these inclusions were diastase-resistant and were also highlighted on Alcian blue staining. Ultrastructural examination revealed chondrocytes with greatly dilated rough endoplasmic reticulum containing granular proteinaceous material. There were also frequent aggregates of typical glycogen. The defect in the COL2A1 gene is secondary to mutations, especially at splice junctions, and this markedly disrupts triple helix formation. The mutated type II procollagen results in intracellular retention within the chondrocytes, as abundant granular proteinaceous material within the dilated RER. A relationship is known to exist between the proportion of mutated to normal type II collagen in the matrix and the severity of the phenotype. With low levels of normal type II collagen, the phenotypic manifestations become more severe, such as in achondrogenesis type II. Both the quantity and quality of type II collagen modulates the phenotypic expression of type II collagenopathies.  相似文献   
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Journal of Neurology - The Clinch Token Transfer Test (C3t) is a bi-manual coin transfer task that incorporates cognitive tasks to add complexity. This study explored the concurrent and convergent...  相似文献   
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BackgroundWomen who engage in higher levels of exercise while trying to quit smoking have been shown to be less likely to relapse and to sustain their smoking abstinence longer. This study sought to examine the benefits of exercise for improving smoking cessation among Black women.MethodsWe evaluated the feasibility of a 12-week smoking and exercise intervention, Quit and Fit, tailored for Black women. All participants (intervention and control) received 12 weeks of smoking cessation counseling via telephone and 9 weeks of nicotine lozenges. Participants who were randomly assigned to the intervention condition were also assigned to a 12-week exercise group.ResultsThirty-eight women were enrolled and 27 completed a 12-week follow-up assessment. Women from the intervention group were more likely to complete the 12-week follow-up assessment compared to participants in the control group (80% vs. 61%). Overall, 7 of the 38 participants (18%) were abstinent at 12 weeks (biochemically verified by expired carbon monoxide). Among the 25 women who completed the 12-week follow-up, abstinence was reported in 33% of the intervention group and 20% of the control group. Using an intent-to-treat approach, 25% of women in the intervention group were abstinent at 12 weeks (n = 5), compared to 11.1% for the control group (n = 2). These differences were not statistically significant.ConclusionsThe overall retention rate was 71% (27/38) at 12 weeks with higher among the intervention group (16/20; 80%) compared to the control group (11/18; 61%). The study demonstrates that it is feasible to retain African-American women in a short-term study of smoking cessation and exercise.  相似文献   
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Avulsion of permanent teeth is one of the most serious dental injuries. Prompt and correct emergency management is essential for attaining the best outcome after this injury. The International Association of Dental Traumatology (IADT) has developed these Guidelines as a consensus statement after a comprehensive review of the dental literature and working group discussions. It represents the current best evidence and practice based on that literature search and expert opinions. Experienced researchers and clinicians from various specialties and the general dentistry community were included in the working group. In cases where the published data did not appear conclusive, recommendations were based on consensus opinions or majority decisions of the working group. They were then reviewed and approved by the members of the IADT Board of Directors. The purpose of these Guidelines is to provide clinicians with the most widely accepted and scientifically plausible approaches for the immediate or urgent care of avulsed permanent teeth. The IADT does not, and cannot, guarantee favorable outcomes from adherence to the Guidelines. However, the IADT believes that their application can maximize the probability of favorable outcomes.  相似文献   
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Traumatic dental injuries (TDIs) occur most frequently in children and young adults. Older adults also suffer TDIs but at significantly lower rates than individuals in the younger cohorts. Luxation injuries are the most common TDIs in the primary dentition, whereas crown fractures are more commonly reported for the permanent teeth. Proper diagnosis, treatment planning and follow up are very important to assure a favorable outcome. These updates of the International Association of Dental Traumatology's (IADT) Guidelines include a comprehensive review of the current dental literature using EMBASE, MEDLINE, PUBMED, Scopus, and Cochrane Databases for Systematic Reviews searches from 1996 to 2019 and a search of the journal Dental Traumatology from 2000 to 2019. The goal of these guidelines is to provide information for the immediate or urgent care of TDIs. It is understood that some follow‐up treatment may require secondary and tertiary interventions involving dental and medical specialists with experience in dental trauma. As with previous guidelines, the current working group included experienced investigators and clinicians from various dental specialties and general practice. The current revision represents the best evidence based on the available literature and expert opinions. In cases where the published data were not conclusive, recommendations were based on the consensus opinions of the working group. They were then reviewed and approved by the members of the IADT Board of Directors. It is understood that guidelines are to be applied using careful evaluation of the specific clinical circumstances, the clinician's judgment, and the patient's characteristics, including the probability of compliance, finances and a clear understanding of the immediate and long‐term outcomes of the various treatment options vs non‐treatment. The IADT does not, and cannot, guarantee favorable outcomes from adherence to the Guidelines. However, the IADT believes that their application can maximize the probability of favorable outcomes.  相似文献   
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