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31.
Unprecedented opportunities and daunting difficulties are anticipated in the future of pediatric pulmonary medicine. To address these issues and optimize pediatric pulmonary training, a group of faculty from various institutions met in 2019 and proposed specific, long‐term solutions to the emerging problems in the field. Input on these ideas was then solicited more broadly from faculty with relevant expertise and from recent trainees. This proposal is a synthesis of these ideas. Pediatric pulmonology was among the first pediatric specialties to be grounded deliberately in science, requiring its fellows to demonstrate expertise in scientific inquiry (1). In the future, we will need more training in science, not less. Specifically, the scope of scientific inquiry will need to be broader. The proposal outlined below is designed to help optimize the practices of current providers and to prepare the next generation to be leaders in pediatric care in the future. We are optimistic that this can be accomplished. Our broad objectives are (a) to meet the pediatric subspecialty workforce demand by increasing interest and participation in pediatric pulmonary training; (b) to modernize training to ensure that future pediatric pulmonologists will be prepared clinically and scientifically for the future of the field; (c) to train pediatric pulmonologists who will add value in the future of pediatric healthcare, complemented by advanced practice providers and artificial intelligence systems that are well‐informed to optimize quality healthcare delivery; and (d) to decrease the cost and improve the quality of care provided to children with respiratory diseases.  相似文献   
32.
Loss of major histocompatibility complex class II (MHC II) expression is associated with poor patient outcome in diffuse large B-cell lymphoma (DLBCL). As MHC II molecules are lost with plasmacytic differentiation in normal cells, we asked whether MHC II loss in DLBCL is associated with an altered differentiation state. We used gene expression profiling, quantum dots, and immunohistochemistry to study the relationship between MHC II and plasma cell markers in DLBCL and plasmablastic lymphoma (PBL). Results demonstrate that MHC II(-) DLBCL immunophenotypically overlap with PBL and demonstrate an inverse correlation between MHC II and plasma cell markers MUM1, PRDM1/Blimp1, and XBP1s. In addition, MHC II expression is significantly higher in germinal center-DLBCL than activated B cell-DLBCL. A minor subset of cases with an unusual pattern of mislocalized punctate MHC II staining and intermediate levels of mRNA is also described. Finally, we show that PBL is negative for MHC II. The results imply a spectrum of MHC II expression that is more frequently diminished in tumors derived from B cells at the later stages of differentiation (with complete loss in PBL). Our observations provide a possible unifying concept that may contribute to the poor outcome reported in all MHC II(-) B-cell tumors.  相似文献   
33.
手术是脉管性病变治疗的一种手段,其主要作用是与放射治疗及各种药物治疗协同作用。对于血管瘤患者,手术仅限于普萘洛尔治疗无效,出现并发症及位于眼部的病变。整形手术可使血管瘤消退后遗留的面部畸形得到改善。对于一些范围较小的局灶性病变,手术往往可以取得满意的效果;对于巨大、多发的血管瘤,手术治疗往往作用有限,常常为减瘤术。手术患者一般在术前均经过栓塞硬化治疗,这样可以大大减少术中出血。手术无法治愈脉管性疾病,是一种辅助  相似文献   
34.
A theory-driven treatment was designed to facilitate access to the impaired output lexicons of a 47-year-old woman with aphasia resulting from a left parietal haemorrhage. In the context of a multiple-baseline design, lists of rhymed word pairs from four semantic categories were trained using a systematic cueing hierarchy. Performance measures were based on the subject's generation of targeted words, verbally and in writing, when presented with a rhyme of the target. Results demonstrated positive acquisition, generalization and maintenance effects for treated and untreated items across semantic categories. Delayed generalization patterns may be explained by retrieval inhibition (Blaxton and Bookheimer 1993) or lateral inhibition (McClelland and Rumelhart 1981).  相似文献   
35.
Abstract

A study by McNeil et al. reported no generalization effects in two individuals with aphasia following application of a word finding treatment in which subjects were trained sequentially on lexical items arranged by form class. The present investigation examined, in one of the two subjects from the original study, whether training on lexical items from a variety of form classes concurrently would result in greater response generalization than was observed previously in this subject. Results replicated earlier findings with positive acquisition and maintenance effects and little evidence of generalization to untrained items within or across form classes.  相似文献   
36.
Urinary exosomes secreted by multiple cell types in the kidney may participate in intercellular signaling and provide an enriched source of kidney-specific proteins for biomarker discovery. Factors that alter the exosomal protein content remain unknown. To determine whether endogenous and exogenous hormones modify urinary exosomal protein content, we analyzed samples from 14 mildly hypertensive patients in a crossover study during a high-sodium (HS, 160 mmol/d) diet and low-sodium (LS, 20 mmol/d) diet to activate the endogenous renin-angiotensin-aldosterone system. We further analyzed selected exosomal protein content in a separate cohort of healthy persons receiving intravenous aldosterone (0.7 μg/kg per hour for 10 hours) versus vehicle infusion. The LS diet increased plasma renin activity and aldosterone concentration, whereas aldosterone infusion increased only aldosterone concentration. Protein analysis of paired urine exosome samples by liquid chromatography-tandem mass spectrometry–based multidimensional protein identification technology detected 2775 unique proteins, of which 316 exhibited significantly altered abundance during LS diet. Sodium chloride cotransporter (NCC) and α- and γ-epithelial sodium channel (ENaC) subunits from the discovery set were verified using targeted multiple reaction monitoring mass spectrometry quantified with isotope-labeled peptide standards. Dietary sodium restriction or acute aldosterone infusion similarly increased urine exosomal γENaC[112–122] peptide concentrations nearly 20-fold, which correlated with plasma aldosterone concentration and urinary Na/K ratio. Urine exosomal NCC and αENaC concentrations were relatively unchanged during these interventions. We conclude that urinary exosome content is altered by renin-angiotensin-aldosterone system activation. Urinary measurement of exosomal γENaC[112–122] concentration may provide a useful biomarker of ENaC activation in future clinical studies.  相似文献   
37.
Glucose is a major source of energy and carbon in promastigotes of Leishmania mexicana, and its uptake is mediated by three glucose transporters whose genes are encoded within a single cluster. A null mutant in which the glucose transporter gene cluster was deleted by homologous gene replacement was generated previously and shown to grow more slowly than wild type promastigotes but not to be viable as amastigotes in primary tissue culture macrophages or in axenic culture. Further phenotypic characterization demonstrates that the null mutant is unable to import glucose, mannose, fructose, or galactose and that each of the three glucose transporter isoforms, LmGT1, LmGT2, and LmGT3, is capable of transporting each of these hexoses. Complementation of the null mutant with each isoform is able to restore growth in each of the four hexoses to wild type levels. Null mutant promastigotes are reduced in size to about 2/3 the volume of wild type parasites. In addition, the null mutants are significantly more sensitive to oxidative stress than their wild type counterparts. These results underscore the importance of glucose transporters in the parasite life cycle and suggest reasons for their non-viability in the disease-causing amastigote stage.  相似文献   
38.

Background

Children with cerebral palsy (CP) have lower habitual physical activity (HPA) than their typically developing peers. There are limited studies of HPA in young children with CP under the age of 5 years.

Objective

To investigate the relationships between HPA, sedentary time, motor capacity and capability in children with CP aged 4–5 years.

Methods

Sixty-seven participants were classified using Gross Motor Function Classification System (GMFCS), assessed for motor capacity using Gross Motor Function Measure (GMFM) and wore accelerometers for three days to measure HPA and sedentary time. Motor capability was assessed using parent-reported Pediatric Evaluation of Disability Inventory (PEDI) functional skills of mobility domain. Mixed-effects regression models were used for analyses.

Results

GMFM was positively associated with HPA (mean difference (MD)?=?19.6 counts/min; 95%CI?=?16.6 to 22.7, p?<?0.001) and negatively associated with sedentary time (MD?=??0.6%; 95%CI?=??0.7 to ?0.5, p?<?0.001). The PEDI was also positively associated with HPA (MD?=?16.0 counts/min; 95%CI?=?13.1 to 18.8, p?<?0.001) and negatively associated with sedentary time (MD?=??0.5%; 95%CI?=??0.6 to ?0.4, p?<?0.001). After stratification for ambulatory status, GMFM and PEDI were associated with HPA and sedentary time in ambulant participants but not in non-ambulant participants.

Conclusions

Gross motor capacity and motor capability are related to HPA and sedentary time in ambulant children with CP aged 4–5 years.  相似文献   
39.
Although research shows that minorities exhibit higher levels of medical mistrust, perceived racism, and discrimination in healthcare settings, the degree to which these underlying sociocultural factors preclude end‐stage renal disease (ESRD) patients from initiating kidney transplant evaluation is unknown. We telephone surveyed 528 adult ESRD patients of black or white race referred for evaluation to a Georgia transplant center (N = 3) in 2014‐2016. We used multivariable logistic regression to examine associations between sociocultural factors and evaluation initiation, adjusting for demographic, clinical, and socioeconomic characteristics. Despite blacks (n = 407) reporting higher levels of medical mistrust (40.0% vs 26.4%, P < .01), perceived racism (55.5% vs 18.2%, P < .01), and experienced discrimination (29.0% vs 15.7%, P < .01) than whites (n = 121), blacks were only slightly less likely than whites to initiate evaluation (49.6% vs 57.9%, P = .11). However, after adjustment, medical mistrust (odds ratio [OR]: 0.59; 95% confidence interval [CI]: 0.39, 0.91), experienced discrimination (OR: 0.62, 95% CI: 0.41, 0.95), and perceived racism (OR: 0.61; 95% CI: 0.40, 0.92) were associated with lower evaluation initiation. Results suggest that sociocultural disparities exist in early kidney transplant access and occur despite the absence of a significant racial disparity in evaluation initiation. Interventions to reduce disparities in transplantation access should target underlying sociocultural factors, not just race.  相似文献   
40.
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