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101.
Introduction: Pulmonary hypertension is a hemodynamic condition occurring rarely in pediatrics. Nevertheless, it is associated with significant morbidity and mortality. When characterized by progressive pulmonary vascular structural changes, the disease is called pulmonary arterial hypertension (PAH). It results in increased pulmonary vascular resistance and eventual right ventricular failure. In the vast majority of cases, pediatric PAH is idiopathic or associated with congenital heart disease, and, contrary to adult PAH, is rarely associated with connective tissue, portal hypertension, HIV infection or thromboembolic disease.

Areas covered: This article reviews the current drug therapies available for the management of pediatric PAH. These treatments target the recognized pathophysiological pathways of PAH with endothelin-1 receptor antagonists, prostacyclin analogs and PDE type 5 inhibitors. New treatments and explored pathways are briefly discussed.

Expert opinion: Although there is still no cure for PAH, quality of life and survival have been improved significantly with specific drug therapies. Nevertheless, management of pediatric PAH remains challenging, and depends mainly on results from adult clinical trials and pediatric experts. Further research on PAH-specific treatments in the pediatric population and data from international registries are needed to identify optimal therapeutic strategies and treatment goals in the pediatric population.  相似文献   

102.
Gastrointestinal stromal tumour (GIST) is a rare tumour of the gastrointestinal tract which does not generally originate in the rectum. The authors describe a case of a 70-year-old man who underwent an anterior resection of the rectum for a low-risk GIST. The patient was not given adjuvant chemotherapy with imatinib and is still disease-free 30 mo after surgery. The authors conclude that although rectal GIST is extremely uncommon, it should be included in differential diagnosis when a tumour in the rectum is detected. Biopsy of the tumour is essential, since this makes it possible to reach a sure preoperative diagnosis based on the immunohistological features of the CDl17 and CD34. Although complete surgical resection with negative tumour margins is the principal curative procedure for primary and nonmetastatic tumours, further studies are still needed for the determination of the most effective treatment strategy for patients with rectal GIST.  相似文献   
103.
目的 探讨术中经食道超声心动图(Transesophageal Echocardiography,TEE)在急性Stanford A型主动脉夹层(AAD)手术中的应用价值。 方法 选取经全主动脉CTA诊断为ADD的患者41例,术前行TEE检查,根据TEE检出主动脉根部受累情况分为三组:夹层未累及主动脉根部组(A组)16例,主动脉根部轻-中度受累组(B组)9例,主动脉根部重度受累组(C组)16例。均行术前TEE检查观察主动脉根部形态、夹层受累情况,包括主动脉瓣叶形态、功能,测量并比较各组主动脉瓣环内径、主动脉窦部内径、窦管交界内径及可显示升主动脉段的最大内径,观察冠状动脉起始段形态;术后TEE即刻观察手术效果。并将TEE结果与术中所见进行比较。结果 41例患者术前TEE对升主动脉内撕裂的内膜片显示阳性率为100%。B、C组主动脉窦部内径均大于A组,C组主动脉窦部内径大于B组,差异均有统计学意义(P<0.05);A、B、C三组患者主动脉瓣环及升主动脉内径比较差异均无统计学意义。经手术证实,术前TEE诊断夹层累及冠状动脉的特异性为62.5%,敏感性为56%。术后TEE可评估人工主动脉瓣或修复主动脉瓣形态、功能,以及人工血管、冠状动脉等吻合情况。结论 术前TEE能准确评估AAD主动脉根部及冠状动脉受累情况,术后TEE可即刻评估手术效果,具有重要的临床应用价值。  相似文献   
104.
为解决医疗费用过快上涨、医保对供方行为约束不足、基金运行风险加剧等问题,人力资源和社会保障部等要求在统筹地区开展以总额控制为主的医保支付方式改革.总额控制对城市大型公立医院的经营管理产生了较大的影响.按照总额控制政策,提出3个层面的转型策略.在发展战略方面,转变增长方式,发挥医联体作用,增强辐射能力;在业务管理方面,确保医疗质量和安全,落实临床路径,优化服务流程;在行政管理方面,强化成本控制,加强信息化建设,转变管理职能.  相似文献   
105.
106.
Background: Children with cerebral palsy (CP) face particular challenges, e.g. daily pain that threaten their participation in school activities. This study focuses on how teachers, personal assistants, and clinicians in two countries with different cultural prerequisites, Sweden and South Africa, manage the pain of children in school settings.

Method: Participants’ statements collected in focus groups were analysed using a directed qualitative content analysis framed by a Frequency of attendance-Intensity of involvement model, which was modified into a Knowing-Doing model.

Results: Findings indicated that pain management focused more on children’s attendance in the classroom than on their involvement, and a difference between countries in terms of action-versus-reaction approaches. Swedish participants reported action strategies to prevent pain whereas South African participants primarily discussed interventions when observing a child in pain.

Conclusion: Differences might be due to school- and healthcare systems. To provide effective support when children with CP are in pain in school settings, an action-and-reaction approach would be optimal and the use of alternative and augmentative communication strategies would help to communicate children’s pain. As prevention of pain is desired, structured surveillance and treatment programs are recommended along with trustful collaboration with parents and access to “hands-on” pain management when needed.
  • Implications for rehabilitation
  • ??When providing support, hands-on interventions should be supplemented by structured preventive programs and routines for parent collaboration (action-and-reaction approach).

  • ??When regulating support, Sweden and South Africa can learn from each other;

  • ○?In Sweden, the implementation of a prevention program has been successful.

  • ○?In South Africa, the possibilities giving support directly when pain in children is observed have been beneficial.

  相似文献   
107.
Purpose: The aim of the present study was to investigate the effectiveness of a prospective memory aid that combines smartphones with Internet-based calendars among community-dwelling patients with traumatic brain injury.

Method: An uncontrolled pre- and post-assessment design was employed to study the use of unmodified, low-cost, off-the-shelf smartphones combined with Internet-calendars as a compensatory memory strategy in community-dwelling patients with traumatic brain injury. Thirteen participants received a 6-week group-based intervention with pre-, post- and 2-month follow-up-assessments by questionnaires and by daily assessment of target behaviors for 2-week periods.

Results: Participants reported significantly fewer retro- and prospective memory problems on questionnaires after the intervention and at follow-up with large effect sizes. The performance of target behaviors, however, improved insignificantly with moderate effect sizes. There were no changes in quality of life or symptoms of emotional distress.

Conclusions: This study adds to a growing body of evidence that smartphones are a useful compensatory aid in rehabilitation of prospective memory that should routinely be considered in rehabilitation of traumatic brain injury patients.

  • Implication for rehabilitation
  • Smartphones are easy-to-use and accessible assistive technology for compensatory memory rehabilitation to most traumatic brain injury patients.

  • By using low-cost, off-the-shelf devices, the technology becomes available to a broader range of patients.

  • By combining smartphones with Internet-based and cross-platform services (e.g., calendars, contacts) the participants are less device-dependent and less vulnerable to data loss.

  • Smartphones should routinely be considered as compensatory aid in rehabilitation of prospective memory of traumatic brain injured patients.

  相似文献   
108.
109.
The regression limited sampling strategy approach (R‐LSS), which is based on a small number of blood samples drawn at selected time points, has been used as an alternative method for the estimation of the area under the concentration–time curve (AUC). However, deviations from planned sampling times may affect the performance of R‐LSS, influencing related therapeutic decisions and outcomes. The aim of this study was to investigate the impact of different sampling time deviation (STD) scenarios on the estimation of AUC by the R‐LSS using a simulation approach. Three types of scenarios were considered going from the simplest case of fixed deviations, to random deviations and then to a more realistic case where deviations of mixed nature can occur. In addition, the sensitivity of the R‐LSS to STD in each involved sampling point was evaluated. A significant impact of STD on the performance of R‐LSS was demonstrated. The tolerance of R‐LSS to STD was found to depend not only on the number of sampling points but more importantly on the duration of the sampling process. Sensitivity analysis showed that sampling points at which rapid concentration changes occur were relatively more critical for AUC prediction by R‐LSS. As a practical approach, nomograms were proposed, where the expected predictive performance of R‐LSS was provided as a function of STD information. The investigation of STD impact on the predictive performance of R‐LSS is a critical element and should be routinely performed to guide R‐LSS selection and use. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
110.
Supervised learning methods promise to improve integrated testing strategies (ITS), but must be adjusted to handle high dimensionality and dose–response data. ITS approaches are currently fueled by the increasing mechanistic understanding of adverse outcome pathways (AOP) and the development of tests reflecting these mechanisms. Simple approaches to combine skin sensitization data sets, such as weight of evidence, fail due to problems in information redundancy and high dimensionality. The problem is further amplified when potency information (dose/response) of hazards would be estimated. Skin sensitization currently serves as the foster child for AOP and ITS development, as legislative pressures combined with a very good mechanistic understanding of contact dermatitis have led to test development and relatively large high‐quality data sets. We curated such a data set and combined a recursive variable selection algorithm to evaluate the information available through in silico, in chemico and in vitro assays. Chemical similarity alone could not cluster chemicals' potency, and in vitro models consistently ranked high in recursive feature elimination. This allows reducing the number of tests included in an ITS. Next, we analyzed with a hidden Markov model that takes advantage of an intrinsic inter‐relationship among the local lymph node assay classes, i.e. the monotonous connection between local lymph node assay and dose. The dose‐informed random forest/hidden Markov model was superior to the dose‐naive random forest model on all data sets. Although balanced accuracy improvement may seem small, this obscures the actual improvement in misclassifications as the dose‐informed hidden Markov model strongly reduced " false‐negatives" (i.e. extreme sensitizers as non‐sensitizer) on all data sets. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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