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Natalie Brown Camilla J. Knight Laura J. Forrest 《Scandinavian journal of medicine & science in sports》2021,31(1):52-69
The purpose of the current study was twofold (a) to examine elite female athletes’ experiences of their menstrual cycle, with a focus upon the impact on training and competition performance and (b) the openness of conversation pertaining to the menstrual cycle with coaching and support staff. Following receipt of institutional ethical approval, individual semi‐structured interviews were conducted with 17 elite female athletes (25.5 ± 4.7 years) from multiple sports. Results revealed athletes’ experiencing a natural menstrual cycle reported physical symptoms alongside mood disturbances and reduced motivation to train. The decision to actively control the menstrual cycle was often triggered by a desire to reduce the effect on competition, to lessen anxieties about making required weight or reduce distraction to manage during competition. Athletes indicated an openness to talk about the menstrual cycle to other females, however, there was variation in the comfort athletes experienced regarding talking to male coaches. Overall, the findings highlight the need to educate elite athletes and coaches on the menstrual cycle, considering it in the same light as other physiological functions in sport to improve health, well‐being, and performance. Furthermore, providing education on how to construct positive conversations, equipping individuals with the correct terminology, and confidence to talk about the menstrual cycle will reduce some reservations identified through improved knowledge and understanding. 相似文献
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Mentorship is considered to play a paramount role in empowering nursing students to recieve superlative benefit from clinical placement. Although the new standards for student supervision and assessment approved by the Nursing and Midwifery Council in 2018 seemed to lead to the disillusionment of mentorship, they support clinical education and devotion to nursing students' clinical learning globally. The aim of this synthesis was to review and explore the experiences of mentorship of preregistration nursing students and nurses. A systematic search of databases was performed for qualitative studies published in English from 2000 to 2018. Eleven qualitative studies were selected, from which three analytical themes emerged: mentors' capabilities and readiness for preregistration nursing student mentorship, humanistic approach as foundation to the effectiveness of preregistration nursing student mentorship, and the collaboration of stakeholders in health care and educational settings to enhance preregistration nursing student mentorship. A thematic framework of mentorship in preregistration nursing education was introduced. The thematic synthesis sheds light on how to improve a formal system of mentorship and clinical supervision for nursing education. 相似文献
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Constantinos Zamboglou Peter Bronsert Simon Küsters Natalie Salm Marc Azèmar Thomas Brunner 《Strahlentherapie und Onkologie》2015,191(1):67-72
Background
Pancreatic cancer (PC) predominantly metastasizes to liver, lung, and peritoneum. Metastatic disease correlates with SMAD4 status. Musculoskeletal metastases (MSM) are rare in pancreatic cancer. The role of radiation therapy (RT) in patients with musculoskeletal metastases is not clear.Methods
We present a case of a woman with musculoskeletal metastases of PC evolving 4 years after Whipple’s procedure and adjuvant therapy. She was treated with RT for 7 MSM. Radiation dose was 15–45 Gy, delivered in doses of 2.5–5 Gy per fraction. SMAD4 status was examined by immunohistochemistry. Furthermore we undertook a review of the literature to examine the value of RT in musculoskeletal metastasis of PC.Results
In the presented patient we treated 7 MSM of SMAD4-mutant PC with RT. RT achieved local control in 4 of the 7 MSM. At the resection margin of one MSM recurrent tumor was observed after RT. The status of one MSM was unknown and one MSM showed local progression. Follow-up revealed progression of pain in 1 of the 7 MSM. Except of hyperpigmentation no side effects occurred. There was no dose–correlation effect on tumor control observed. A review of the literature showed that a musculoskeletotrophic phenotype of metastases is rare in PC. MSM of PC are rapidly increasing soft tissue masses causing pain and loss of anatomical function. RT as a treatment option for musculoskeletal metastasis is described in the current literature in only 2 cases. Radiotherapy aims to achieve local control, pain relief, and to maintain anatomical function.Conclusion
Radiotherapy is an effective and well-tolerated approach for multiple musculoskeletal metastases of PC.107.
Background
Ultrahigh-molecular-weight polyethylene (UHMWPE) is subjected to radiation crosslinking to form highly crosslinked polyethylene (HXLPE), which has improved wear resistance. First-generation HXLPE was subjected to thermal treatment to reduce or quench free radicals that can induce long-term oxidative degeneration. Most recently, antioxidants have been added to HXLPE to induce oxidative resistance rather than by thermal treatment. However, antioxidants can interfere with the efficiency of radiation crosslinking.Questions/purposes
We sought to identify (1) which antioxidant from among those tested (vitamin E, β-carotene, butylated hydroxytoluene, or pentaerythritol tetrakis [methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate]) causes the least reduction of crosslinking; (2) which promotes the greatest oxidative stability; and (3) which had the lowest ratio of oxidation index to crosslink density.Methods
Medical-grade polyethylene (PE) resin was blended with 0.1 weight % of the following stabilizers: alpha tocopherol (vitamin E), β-carotene, butylated hydroxytoluene (BHT), and pentaerythritol tetrakis [methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (a hindered phenol antioxidant [HPAO]). These blends were compression-molded into sheets and subjected to electron beam irradiation to a dose of 100 kGy. Equilibrium swelling experiments were conducted to calculate crosslink density. Each PE was subjected to accelerated aging for a period of 2 weeks and Fourier transform infrared spectroscopy was used to measure the maximum oxidation. Statistical analysis was conducted using analysis of variance with Fisher’s protected least significant difference in which a p value of < 0.05 was used to define a significant difference.Results
The least reduction of crosslinking in antioxidant-containing HXLPE was observed with HPAO, which had a crosslink density (n = 6) of 0.167 (effect size [ES] = 0.87; 95% confidence interval [CI], 0.162–0.173) mol/dm3 compared with 0.139 (ES = 1.57; 95% CI, 0.132–0.146) mol/dm3 (p = 0.020) for BHT, 0.131 (ES = 1.77; 95% CI, 0.123–0.139) mol/dm3 (p = 0.004) for β-carotene, and 0.130 (ES = 1.79; 95% CI, 0.124–0.136) mol/dm3 (p = 0.003) for vitamin E, whereas pure HXLPE had a crosslink density of 0.203 (95% CI, 0.170–0.235) mol/dm3 (p = 0.005). BHT-PE had an oxidation index of 0.21 (ES = 13.14; 95% CI, 0.19–0.22) followed by HPAO-PE, vitamin E-PE and β-carotene-PE, which had oxidation indices of 0.28 (ES = 9.68; 95% CI, 0.28–0.29), 0.29 (ES = 9.59; 95% CI, 0.27–0.30), and 0.35 (ES = 6.68; 95% CI, 0.34–0.37), respectively (p < 0.001 for all groups). BHT-PE had the lowest ratio of oxidation index to crosslink density of the materials tested (1.49, ES = 1.94; 95% CI, 1.32–1.66) followed by HPAO-PE (1.70, ES = 1.52; 95% CI, 1.61–1.80), vitamin E-PE (2.21, ES = 0.52; 95% CI, 2.05–2.38), and β-carotene-PE (2.69, ES = -0.43; 95% CI, 2.46–2.93) compared with control PE (2.47, 95% CI, 2.07–2.88) with β-carotene (p = 0.208) and vitamin E (p = 0.129) not being different from the control.Conclusions
BHT-modified HXLPE was found in this study to have the lowest oxidation index as well as the lowest ratio of oxidation index to crosslink density compared with vitamin E, HPAO, and β-carotene-modified HXLPEs. More comprehensive studies are required such as wear testing using joint simulators as well as biocompatibility studies before BHT-modified HXLPE can be considered for clinical use.Clinical Relevance
BHT is a synthetic antioxidant commonly used in the polymer industry to prevent long-term oxidative degradation and has been approved by the FDA for use in cosmetics and foodstuffs. It may be an attractive potential stabilizer for HXLPE in total joint replacements. 相似文献108.
Rebecca E. Graff Andreas Pettersson Rosina T. Lis Natalie DuPre Kristina M. Jordahl Elizabeth Nuttall Jennifer R. Rider Michelangelo Fiorentino Howard D. Sesso Stacey A. Kenfield Massimo Loda Edward L. Giovannucci Bernard Rosner Paul L. Nguyen Christopher J. Sweeney Lorelei A. Mucci 《The Prostate》2015,75(9):897-906
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