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71.
Correction for ‘Self-assembled fibrillar networks comprised of a naturally-occurring cyclic peptide—LOB3’ by M. A. Rogers et al., RSC Adv., 2016, 6, 40765–40776.

The authors regret the omission of the following conflict of interest statement.Dr Martin J. T. Reaney is the founder of, and has an equity interest in, Prairie Tide Diversified Inc. (PTD, Saskatoon, SK, Canada: previous company name is Prairie Tide Chemicals Inc.). Dr Youn Young Shim is a Market Consultant for PTD in Korea. The terms of this arrangement have been reviewed and approved by the University of Saskatchewan in accordance with its conflict of interest policies.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
72.

Purpose

Cost effectiveness is an increasingly important factor in today’s healthcare environment, and selection of arthroplasty implant is not exempt from such concerns. Quality adjusted life years (QALYs) are the typical tool for this type of evaluation. Using this methodology, joint arthroplasty has been shown to be cost effective; however, studies directly comparing differing prostheses are lacking.

Methods

Data was gathered in a single-centre prospective double-blind randomised controlled trial comparing the outcome of modern and traditional knee implants, using the Short Form 6 dimensional (SF-6D) score and quality adjusted life year (QALY) methodology.

Results

There was significant improvement in the SF-6D score for both groups at one year (p?<?0.0001). The calculated overall life expectancy for the study cohort was 15.1 years, resulting in an overall QALY gain of 2.144 (95 % CI 1.752–2.507). The modern implant group demonstrated a small improvement in SF-6D score compared to the traditional design at one year (0.141 versus 0.143, p?=?0.94). This difference resulted in the modern implant costing £298 less per QALY at one year.

Conclusion

This study demonstrates that modern implant technology does not influence the cost-effectiveness of TKA using the SF-6D and QALY methodology. This type of analysis however assesses health status, and is not sensitive to joint specific function. Evolutionary design changes in implant technology are thus unlikely to influence QALY analysis following joint replacement, which has important implications for implant procurement.  相似文献   
73.

Background

The odontoid lateral mass interspace (OLMI) is the space between the lateral aspect of the dens axis and the medial circumference of the massa lateralis atlantis. The position of OLMI asymmetry as a normal variant or pathologic finding is an area of debate and clinical interest in trauma patients. We designed this prospective study to lay a framework for proposing strategies for the appropriate use of OLMI.

Methods

A total of 301 adult patients admitted for trauma were included. Computed tomography (CT) and magnetic resonance imaging (MRI) of the cervical spine were performed and examined for the presence OLMI asymmetry and bony/ligamentous lesions of the occipitoatlantoaxial complex.

Results

Head rotation is linked to the occurrence of OLMI asymmetry. Reliable OLMI asymmetry evaluation is limited by observer agreement under a threshold value of 1.0 mm. In all, 86 patients (28.6 %) were found to have OLMI asymmetry on CT after trauma. Among these patients, 17.4 % had a bony/ligamentous lesion of the occipitoatlantoaxial complex. Among the patients without OLMI asymmetry, 8.8 % were found to have such lesions.

Conclusions

OLMI asymmetry should only be investigated by CT scans of the head in optimal position and with the threshold value of 1.0 mm. OLMI asymmetry should not be used alone as a sign of a cervical spine lesion. MRI should be performed if: (1) the physician has a high degree of suspicion of a cervical spine lesion; (2) OLMI asymmetry was demonstrated on a technically adequate CT scan; (3) clinical symptoms persist in patients with OLMI asymmetry when no acute MRI was performed.  相似文献   
74.
Cervical spine injuries in Rugby Union are a concerning issue at all levels of the game. The primary aim of this retrospective analysis conducted in a professional Rugby Union squad was to determine whether a 26-week isometric neck strengthening intervention program (13-week strengthening phase and 13-week maintenance phase) was effective in reducing the number and severity of cervical spine injuries. The secondary aim was to determine whether at week five, where the program had been the similar for all players, there was increased isometric neck strength. All 27 players who were common to both the 2007-2008 and 2008-2009 seasons were included in this analysis and data was extracted from a Sports Medicine/Sports Science database which included the squad''s injury records. Primary outcome variables included; the number of cervical spine injuries and the severity of these injuries as determined by the total number of days lost from training and competition. Secondary outcome variables included isometric neck strength in flexion, extension and left and right lateral flexion. Using non-parametric statistical methods, no significant differences were evident for the total number of cervical spine injuries (n = 8 in 2007-2008, n = 6 in 2008-2009) or time loss due to these injuries (100 days in 2007-2008, 40 days in 2008-2009). However, a significant (p = 0.03) reduction in the number of match injuries was evident from 2007-2008 (n = 11) to 2008-09 (n = 2). Non-significant increases in isometric neck strength were found in all directions examined. A significant reduction in the number of match injuries was evident in this study. However, no other significant changes to primary outcome variables were achieved. Further, no significant increases in isometric neck strength were found in this well-trained group of professional athletes.

Key Points

  • While many authors have proposed that neck strengthening could be an effective strategy in preventing cervical spine injuries in Rugby Union, there is currently little information in the literature pertaining to how such a study might be conducted.
  • A significant decrease in the number of injuries recorded in matches can be achieved using a specific neck strengthening program at the elite level.
  • In an elite rugby union team as investigated in this study a significant increase in neck strength is difficult to achieve in a short period of time such as five weeks.
Key words: Rugby Union, cervical spine, injury, isometric, neck strength  相似文献   
75.
In 2007 in the UK, 5410 people were diagnosed with an oral cancer. It is therefore imperative that all dentists, medical practitioners and dental care practitioners are vigilant when examining the oral cavity so that any suspicious ulcers, swellings or changes in colour of the mucosa are referred at the earliest stage. To give the patient the best prognosis with an orofacial defect following tumour removal or trauma, it is most important to have the appropriate skills in a multidisciplinary team. The management of patients comprises pre-surgical, surgical and post-surgical phases.  相似文献   
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78.
Venous thromboembolism (VTE) is a significant healthcare burden with approximately 900,000 events annually in the United States, over half of which are healthcare-associated. This number is anticipated to double by 2050. Group prophylaxis strategies confined to the inpatient setting appear to have minimal impact on the reduction of post-discharge VTE in medically ill patients due to shortened lengths of stay and a heterogenous population that includes patients at low risk for VTE. In accordance with current guideline recommendations, very few (<5%) medically ill patients are discharged with extended prophylaxis, which potentially creates a clinical gap for at-risk patients as VTE risk has been shown to persist for up to 90 days. Initial studies of extended thromboprophylaxis in acutely ill medical patients with enoxaparin, rivaroxaban and apixaban showed little to no benefit towards VTE reduction that was consistently outweighed by increased bleeding. The more recent APEX study that compared betrixaban to enoxaparin in an enriched patient population at high-risk for VTE was the first study of extended thromboprophylaxis that showed similar efficacy in VTE prevention without an increase in major bleeding. Based on the APEX results, betrixaban recently gained FDA approval for extended thromboprophylaxis in acutely ill medical patients. Recognition that up to half of medically ill patients are not at sufficient risk to warrant thromboprophylaxis has driven extensive research towards development of scientifically derived and validated VTE risk assessment models intended to identify patients who do not warrant prophylaxis, as well as those at high risk who may derive benefit from extended thromboprophylaxis. This article will review prior and ongoing extended thromboprophylaxis studies, VTE and bleed risk assessment models, incorporation of biomarkers in VTE risk assessment and key issues in the paradigm shift towards individualized VTE prophylaxis in acutely ill medical patients.  相似文献   
79.
Precision requirements for cost-effective operation of analytical processes   总被引:13,自引:0,他引:13  
Current performance criteria for analytical methods are often based on recommendations developed many years ago. A common criterion for imprecision requires that two times the standard deviation (s) of the method be less than the allowable total error (TEa). Unfortunately, when this criterion is minimally satisfied, commonly used control procedures cannot achieve reliable detection of medically important errors. Studies of the power functions for statistical quality-control (QC) procedures show that the magnitude of medically important errors must be at least 3s to fall near the plateau of the power curves and be readily detected by current QC procedures. For methods that just meet the precision criterion 2s less than TEa, however, medically important errors will fall on the rising portion of the power curves and typically be detected less than half of the time. From a "reverse engineering" perspective, the 2s less than TEa criterion is inadequate because it does not allow for the known performance limitations (lack of sensitivity) of commonly used control procedures. A strong case can be made for using a criterion of at least '4s less than TEa, which calls for a twofold improvement in imprecision over, the current minimum requirements. This recommendation is consistent with current industrial guidelines for process capability and would lead to more reliable detection of medically important errors.  相似文献   
80.
目的:神经断端保留小间隙的静脉桥接模拟神经外膜形成神经再生室,为周围神经再生创造了良好的生理环境,从而保证神经束的良好对合。实验采用部分脱乙酰甲壳质作为套管材料,用小间隙桥接方法修复坐骨神经损伤,观察套管内的神经再生情况,并与传统外膜缝合法进行比较。方法:实验于2001-01/2002-10在北京大学人民医院创伤骨科实验室完成。①主要材料:实验所用中空圆柱形套管为北京大学人民医院与中国纺织科学院共同发明的一种部分脱乙酰甲壳质生物套管(专利号:01136314.2)。实验中所用套管尺寸为:管长4 mm,壁厚0.1 mm,内径1.5 mm。②实验动物:健康成年雄性SD大鼠20只,随机分成2大组,每组10只,每一大组全部10只动物的左腿坐骨神经为一组,右腿坐骨神经为另一组,每组10根坐骨神经。另取5只同样大鼠双侧坐骨神经未做处理作为正常对照组。③实验方法:外膜原位缝合组:切断坐骨神经,显微镜下神经外膜原位缝合;生物套管小间隙原位桥接组:切断坐骨神经,显微镜下小间隙套管桥接;断端旋转180°外膜缝合组:切断坐骨神经,显微镜下远端旋转180°后,神经外膜缝合;断端旋转180°生物套管小间隙桥接组:切断坐骨神经,显微镜下远端旋转180°后,小间隙套管桥接。④实验评估:术后第7,14,21,28,42天取坐骨神经,进行免疫组织化学染色及观察。结果:再生神经延套管中央走行,7 d时已有部分纤维通过2 mm间隙,14 d时有髓纤维数量明显多于近端。21 d后,套管组与原位外膜组新生有髓神经纤维数相近。再生纤维胞核数量较多,髓鞘纤细。套管结构完整。结论:此种部分脱乙酰甲壳质生物套管内的再生神经连续、整齐,髓鞘完整,其神经再生情况好于传统外膜缝合法。  相似文献   
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