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We report the case of an 8-year-old boy with a parotid mass diagnosed to be a leiomyosarcoma. Considering the unresectable extent of the mass, the patient was subjected to radiotherapy. The patient developed distant metastasis following the course of radiotherapy and was put on chemotherapy. The child was lost to further follow up. To our knowledge, this is the first reported case in the English-language literature of such an entity in the pediatric age group.  相似文献   
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The effect of dietary supplementation with Vitamin E was studied in sensitized guinea pigs. After measurement of baseline airway reactivity and sensitization with ovalbumin, the animals were randomized into two groups: Group A, on a commercial feed and Group B, on dietary supplementation with oral Vitamin E (0.7 IU/kg). These were challenged with inhaled ovalbumin after 4 weeks. The following outcomes were studied: airway responses to ovalbumin inhalation, airway reactivity, sodium and calcium ion influx in isolated tracheal cells, Na+ K+ ATPase and Ca2+ ATPase activity in tracheal homogenate and plasma malonaldehyde. Sensitization increased airway reactivity in Group A but not in Group B. The tracheal cells of animals in Group B showed significantly lower rates of 45Ca and 22Na influx and lower activities of tracheal Na+ K+ ATPase and Ca2+ ATPase as compared to Group A. Plasma malonaldehyde was similar between two groups. We concluded that Vitamin E suppresses the increase in airway reactivity following sensitization and has membrane stabilizing actions.  相似文献   
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In the Women's Health Initiative (WHI), we investigated associations between baseline dual-energy X-ray absorptiometry (DXA) appendicular lean mass (ALM) and risk of incident fractures, falls, and mortality (separately for each outcome) among older postmenopausal women, accounting for bone mineral density (BMD), prior falls, and Fracture Risk Assessment Tool (FRAX®) probability. The WHI is a prospective study of postmenopausal women undertaken at 40 US sites. We used an extension of Poisson regression to investigate the relationship between baseline ALM (corrected for height2) and incident fracture outcomes, presented here for major osteoporotic fracture (MOF: hip, clinical vertebral, forearm, or proximal humerus), falls, and death. Associations were adjusted for age, time since baseline and randomization group, or additionally for femoral neck (FN) BMD, prior falls, or FRAX probability (MOF without BMD) and are reported as gradient of risk (GR: hazard ratio for first incident fracture per SD increment) in ALM/height2 (GR). Data were available for 11,187 women (mean [SD] age 63.3 [7.4] years). In the base models (adjusted for age, follow-up time, and randomization group), greater ALM/height2 was associated with lower risk of incident MOF (GR = 0.88; 95% confidence interval [CI] 0.83–0.94). The association was independent of prior falls but was attenuated by FRAX probability. Adjustment for FN BMD T-score led to attenuation and inversion of the risk relationship (GR = 1.06; 95% CI 0.98–1.14). There were no associations between ALM/height2 and incident falls. However, there was a 7% to 15% increase in risk of death during follow-up for each SD greater ALM/height2, depending on specific adjustment. In WHI, and consistent with our findings in older men (Osteoporotic Fractures in Men [MrOS] study cohorts), the predictive value of DXA-ALM for future clinical fracture is attenuated (and potentially inverted) after adjustment for femoral neck BMD T-score. However, intriguing positive, but modest, associations between ALM/height2 and mortality remain robust. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Individuals with cystic fibrosis (CF) have an increased risk for gallbladder abnormalities and biliary tract disease, but the reported incidence of these manifestations of CF varies widely in the literature. With the approval of elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA), increasing numbers of CF patients have been initiated on highly effective cystic fibrosis transmembrane regulator (CFTR) modulator therapy. While elevations in hepatic panel are known potential side effects of CFTR modulators, there have been no published cases of biliary disease or acute cholecystitis attributed to these medications. In this case series, we describe seven patients at two adult CF centers with biliary colic shortly after initiation with ELX/TEZ/IVA, six of whom required cholecystectomy.  相似文献   
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A rare case of splenic abscess occurring after blunt abdominal trauma in a previously healthy boy is reported. The diagnosis was made by ultrasonography. The patient recovered after splenectomy and drainage of subphrenic and intraperitoneal pus.  相似文献   
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The advent of biologics in dermatologic treatment armentarium has added refreshing dimensions, for it is a major breakthrough. Several agents are now available for use. It is therefore imperative to succinctly comprehend their pharmacokinetics for their apt use. A concerted endeavor has been made to delve on this subject. The major groups of biologics have been covered and include: Drugs acting against TNF-α, Alefacept, Ustekinumab, Rituximab, IVIG and Omalizumab. The relevant pharmacokinetic characteristics have been detailed. Their respective label (approved) and off-label (unapproved) indications have been defined, highlighting their dosage protocol, availability and mode of administration. The evidence level of each indication has also been discussed to apprise the clinician of their current and prospective uses. Individual anti-TNF drugs are not identical in their actions and often one is superior to the other in a particular disease. Hence, the section on anti-TNF agents mentions the literature on each drug separately, and not as a group. The limitations for their use have also been clearly brought out.  相似文献   
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Abstract

Cell microencapsulation can be used in tissue engineering as a scaffold or physical barrier that provides immunoisolation for donor cells. When used as a barrier, microencapsulation shields donor cells from the host immune system when implanted for cell therapies. Maximizing therapeutic product delivery per volume of microencapsulated cells necessitates first optimising the viability of entrapped cells. Although cell microencapsulation within alginate is well described, best practices for cell microencapsulation within polyethylene glycol is still being elucidated. In this study we microencapsulate mouse preosteoblast cells within polyethylene glycol diacrylate (PEGDA) hydrogel microspheres of varying molecular weight or seeding densities to assess cell viability in relation to cell density and polymer molecular weight. Diffusion studies revealed molecule size permissible by each molecular weight PEGDA towards correlating viability with polymer mesh size. Results demonstrated higher cell viability in higher molecular weight PEGDA microspheres and when cells were seeded at higher cell densities.  相似文献   
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