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Attenuation coefficient estimation has the potential to be a useful tool for placental tissue characterization. A current challenge is the presence of inhomogeneities in biological tissue that result in a large variance in the attenuation coefficient estimate (ACE), restricting its clinical utility. In this work, we propose a new Attenuation Estimation Region Of Interest (AEROI) selection method for computing the ACE based on the (i) envelope signal-to-noise ratio deviation and (ii) coefficient of variation of the transmit pulse bandwidth. The method was first validated on a tissue-mimicking phantom, for which an 18%–21% reduction in the standard deviation of ACE and a 14%–24% reduction in the ACE error, expressed as a percentage of reported ACE, were obtained. A study on 59 post-delivery clinically normal placentas was then performed. The proposed AEROI selection method reduced the intra-subject standard deviation of ACE from 0.72 to 0.39 dB/cm/MHz. The measured ACE of 59 placentas was 0.77 ± 0.37 dB/cm/MHz, which establishes a baseline for future studies on placental tissue characterization.  相似文献   
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Purpose: Discuss the effectiveness of locomotor training (LT) in children following spinal cord injury (SCI). This intervention was assessed following an exhaustive search of the literature using the Preferred Reporting Items for Systematic Reviews and Meta- Analyses: The PRISMA Statement as a guideline.

Method: Six databases were searched including PubMed, PEDro, CINAHL, Cochrane, PsycINFO, and Web of Knowledge in January 2016 and November 2016, without date restrictions. Inclusion criteria were: studies in English and peer-reviewed and journal articles with a primary intervention of LT in children following SCI.

Results: Twelve articles, reporting eleven studies, were included. A systematic review assessing locomotor training in children with SCI published in April 2016 was also included. Participants were ages 15 months to 18 years old. Forms of LT included body-weight supported treadmill or over ground training, functional electrical stimulation, robotics, and virtual reality. Protocols differed in set-up and delivery mode, with improvements seen in ambulation for all 41 participants following LT.

Conclusion: Children might benefit from LT to develop or restore ambulation following SCI. Age, completeness, and level of injury remain the most important prognostic factors to consider with this intervention. Additional benefits include improved bowel/ bladder management and control, bone density, cardiovascular endurance, and overall quality of life. Looking beyond the effects LT has just on ambulation is crucial because it can offer benefits to all children sustaining a SCI, even if restoration or development of walking is not the primary goal. Further rigorous research is required to determine the overall effectiveness of LT.  相似文献   

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World Journal of Surgery - Routine preoperative staging in pancreas cancer is controversial. We sought to evaluate the rates of diagnostic laparoscopy (DLAP) for pancreatic cancer. We queried the...  相似文献   
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Objective

Adverse events which result from medication errors are considered to be one of the most frequently encountered patient safety issues in clinical settings. We undertook a qualitative investigation to identify and explore factors relating to medication error in an adult oncology department in Saudi Arabia from the perspective of healthcare professionals.

Methods

This was a qualitative study conducted in an adult oncology department in Saudi Arabia. After obtaining required ethical approvals and written consents from the participants, semi-structured interviews and focus group discussions were carried out for data collection. A stratified purposive sampling strategy was used to recruit medical doctors, pharmacists, and nurses. NVivo Pro version 11 was used for data analyses. Inductive thematic analysis was adopted in the primary coding of data while secondary coding of data was carried out deductively applying the Hospital Survey of Patient Safety Culture (HSOPSC) framework.

Result

The total number of participants were 38. Majority of the participants were nurses (n?=?24), females (n?=?30), and not of Saudi nationality (n?=?31) with an average age of 36?years old. Causes of medication errors were categorized into 6 themes. These causes were related teamwork across units, staffing, handover of medication related information, accepted behavioural norms, frequency of events reported, and non-punitive response to error.

Conclusion

There were numerous causes for medication errors in the adult oncology department. This means substantive improvement in medication safety is likely to require multiple, inter-relating, complex interventions. More research should be conducted to examine context-specific interventions that may have the potential to improve medication safety in this and similar departments.  相似文献   
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