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Pre-operative optimisation is a heterogenous group of interventions aimed at improving peri-operative outcomes. To understand the evidence for pre-operative optimisation in the developing world, we systematically reviewed Cochrane reviews on the topic according to the Human Developmental Index (HDI) of the country where patient recruitment occurred. We used summary statistics and cartograms to describe the HDI, year of publication, timing of pre-operative intervention and risk of bias associated with each included trial. We assessed the impact of multinational trials on the risk of bias introduced by countries of differing HDI. Four-hundred and nine trials representing 51 countries and 89,389 randomly allocated participants were summarised in this review. Four-hundred and nineteen out of 451 (93%) trial populations (i.e. a group of study participants from one country) were from high and very high HDI countries. The median (IQR [range]) HDI of countries were 0.862 (0.806–0.892 [0.445–0.949]). Three of the 409 included trials were multinational, representing 32 countries and 37,736 out of 89,389 (42.2%) included participants. Africa was the least represented continent, with only 4 included trials and 566 participants, of which 62.3% were from one multinational trial. The overall risk of bias was high or unclear in 381 out of 409 (93%) trials. Inclusion of multinational trials decreased the proportion of trial populations introducing high or unclear risk of bias by 9.4% (95%CI 5.1–13.7; p < 0.0001). Half of the world's population live in low- and middle-HDI countries. This population is poorly represented in systematically reviewed evidence on pre-operative optimisation. Multinational trials increase the knowledge contribution from low- and middle-HDI countries and decrease risk of bias in systematic reviews.  相似文献   
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Purpose

The aim of this investigation was to suggest practices to improve the delivery of work-integrated learning (WIL) in radiography training in South Africa (SA).

Methods

An extensive survey was conducted among all universities in SA involved in the training of radiography students, to investigate the current delivery of WIL. Data were collected by means of quantitative questionnaires with open-ended qualitative components. The questionnaire was distributed to lecturers (n = 32), clinical supervisors (n = 44) and final-year students in Radiography (n = 146).

Results

The quantitative (closed questions) and qualitative (open-ended comments) findings from the stakeholders with regard to the improvement of practice in the delivery of WIL in radiography training are presented in this article. The main themes discussed relate to curriculum design for WIL, teaching/learning of WIL, assessment of WIL and management and coordination of WIL.

Conclusion

WIL is a powerful pedagogy if implemented and managed correctly. The results from this study may enable lecturers in radiography programmes in SA to improve the delivery of WIL in the training of high quality, employable graduates.  相似文献   
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目的 利用高频超声对女性肛门括约肌进行显像与评价,验证高频超声运用于女性肛门括约肌完整性评估的可行性。方法 2020年1月-2021年3月期间行盆底超声检查的110例女性受检者,通过高频线阵探头分别从横断面及矢状面对其肛门括约肌进行连续性扫查,而后两位经验不同的研究人员在互盲情况下独立对肛门括约肌的影像进行完整性评价,记录肛门括约肌损伤情况并进行统计分析。结果 在全部受检者中,高频超声均可从横断面及矢状面清晰地显示各水平肛管特征性的解剖结构,从而当出现异常的超声表现时,可以实现对肛门括约肌损伤的检出。通过Kappa一致性检验可得高频超声对肛门括约肌的完整性评价在不同经验的研究人员间也具有较强的一致性(Kappa=0.888,P<0.05)。结论 高频超声通过对各水平肛管的清晰成像,可以实现对肛门括约肌的完整性评价,为肛门括约肌的评估提供一种新的影像学手段。  相似文献   
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Spermatozoa are highly specialized cells. Adenosine triphosphate (ATP), which provides the energy for supporting the key functions of the spermatozoa, is formed by 2 metabolic pathways, namely glycolysis and oxidative phosphorylation (OXPHOS). It is produced in the mitochondria through OXPHOS as well as in the head and principal piece of the flagellum through glycolysis. However, there is a great discrepancy as to which method of ATP production is primarily utilized by the spermatozoa for successful fertilization. Mitochondrial respiration is considered to be a more efficient metabolic process for ATP synthesis in comparison to glycolysis. However, studies have shown that the diffusion potential of ATP from the mitochondria to the distal end of the flagellum is not sufficient to support sperm motility, suggesting that glycolysis in the tail region is the preferred pathway for energy production. It is suggested by many investigators that although glycolysis forms the major source of ATP along the flagellum, energy required for sperm motility is mainly produced during mitochondrial respiration. Nevertheless, some studies have shown that when glycolysis is inhibited, proper functioning and motility of spermatozoa remains intact although it is unclear whether such motility can be sustained for prolonged periods of time, or is sufficiently vigorous to achieve optimal fertilization. The purpose of this article is to provide an overview of mammalian sperm energy metabolism and identify the preferred metabolic pathway for ATP generation which forms the basis of energy production in human spermatozoa during fertilization.  相似文献   
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David M. Fleischer  Scott Sicherer  Matthew Greenhawt  Dianne Campbell  Edmond Chan  Antonella Muraro  Susanne Halken  Yitzhak Katz  Motohiro Ebisawa  Lawrence Eichenfield  Hugh Sampson  Gideon Lack  George Du Toit  Graham Roberts  Henry Bahnson  Mary Feeney  Jonathan Hourihane  Jonathan Spergel  Michael Young  Amal As'aad  Katrina Allen  Susan Prescott  Sandeep Kapur  Hirohisa Saito  Ioana Agache  Cezmi A. Akdis  Hasan Arshad  Kirsten Beyer  Anthony Dubois  Philippe Eigenmann  Monserrat Fernandez‐Rivas  Kate Grimshaw  Karin Hoffman‐Sommergruber  Arne Host  Susanne Lau  Liam O'Mahony  Clare Mills  Nikolaus Papadopoulos  Carina Venter  Nancy Agmon‐Levin  Aaron Kessel  Richard Antaya  Beth Drolet  Lanny Rosenwasser 《Pediatric dermatology》2016,33(1):103-106
The purpose of this brief communication is to highlight emerging evidence regarding potential benefits of supporting early rather than delayed peanut introduction during the period of complementary food introduction in infants. This document should be considered as interim guidance based on consensus among the following organizations: American Academy of Allergy, Asthma, and Immunology, American Academy of Pediatrics, American College of Allergy, Asthma, and Immunology, Australasian Society of Clinical Immunology and Allergy, Canadian Society of Allergy and Clinical Immunology, European Academy of Allergy and Clinical Immunology, Israel Association of Allergy and Clinical Immunology, Japanese Society for Allergology, Society for Pediatric Dermatology, and World Allergy Organization. More formal guidelines regarding early‐life, complementary feeding practices and the risk of allergy development will follow in the next year from the National Institute of Allergy and Infectious Diseases—sponsored Working Group and the European Academy of Allergy and Clinical Immunology.  相似文献   
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