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991.
BackgroundTotal shoulder arthroplasty (TSA) is an increasingly common treatment for end-stage glenohumeral osteoarthritis. Current established radiographic measures and classification systems do not predict patient-reported outcomes from TSA. We hypothesized that the MRI-based Shoulder Osteoarthritis Severity (SOAS) Score would correlate with subjective improvement following TSA.MethodsPatients undergoing TSA with preoperative shoulder MRIs and pre- and postoperative ASES scores with minimum 2-year follow-up were included from a prospectively collected institutional shoulder arthroplasty database. SOAS scores, which is measured from 0 to 100 with an increasing score reflecting greater global degenerative changes, were assessed by two independent reviewers, and Samilson-Prieto grade and Walch classification were scored by one reviewer. Average SOAS scores were correlated with demographic factors and pre-, post-, and change (Δ) in ASES scores. Statistical analysis was performed with STATA with Pearson's correlation, one-way ANOVA, and ROC analysis, with significance defined by p <.05.Results30 patients (age 63 ± 10 years, 14 females, 16 males) who underwent primary anatomic TSA were included. The intraclass correlation coefficient (ICC) for total SOAS scores calculated by reviewers was 0.91. SOAS score correlated significantly with ΔASES (r = 0.61, p = .0003) and preoperative ASES (r = -0.37, p = .042), with greater MRI-based degenerative change associated with greater improvement after TSA and lower preoperative ASES score. No significant relationship was found between either Samilson-Prieto or Walch classification and SOAS or ASES scores. No significant relationship was found between SOAS scores and age, sex, or BMI. Using an MCID of 21 as previously reported, an ROC curve was generated and found to have an AUC of 0.96. A SOAS score cut-point of 36.25 was found to maximize sensitivity and specificity in predicting reaching MCID.ConclusionWe observed a significant positive correlation between the MRI-based SOAS score and functional improvement following TSA measured using change in ASES scores, indicating that patients with more advanced degenerative changes on MRI had greater improvement after shoulder replacement surgery. We found that the correlation strength was highest when comparing total SOAS score to ΔASES as opposed to any individual sub-component of the SOAS score. The MRI-based SOAS score for shoulder osteoarthritis may be a valuable tool for predicting patient outcomes following TSA.Level of evidenceLevel III; Retrospective Cohort Comparison; Prognosis Study  相似文献   
992.
Australia has the second highest rate of non-traumatic lower extremity amputation (LEA) globally. Australia's large geographical size is one of the biggest challenges facing limb preservation services and may be contributing to LEA. The aim of this study was to determine what factors contribute to the likelihood of LEA in people with active foot ulceration in regional Australia. This retrospective cohort study audited patients with active foot ulceration in a multidisciplinary high risk foot service (HRFS) in regional Australia. Neurological, vascular and wound characteristics were systematically extracted, along with demographic information. Participants were followed for at least 12 months until healing or LEA occurred. Correlations between LEA and clinical and demographic characteristics were assessed using the Pearson's product moment correlation coefficient and chi squared test for independence. Significant variables (p < 0.05) were included in the model. Direct logistic regression assessed the independent contribution of significantly correlated variables on the likelihood of LEA. Of note, 1876 records were hand screened with 476 participants (25%) meeting the inclusion criteria. Geographical distance from the HRFS, toe systolic pressure (TSP), diabetes and infection were all significantly correlated with LEA and included in the logistic regression model. TSP decrease of 1 mmHg (OR 1.02, 95% CI 1.01–1.03), increased geographical distance (1 km) from HRFS (OR 1.006, 95% CI 1.001–1.01) infection (OR 2.08, 95% CI 1.06–4.07) and presence of diabetes (OR 3.77, 95% CI 1.12–12.65) were all significantly associated with increased likelihood of LEA. HRFS should account for the disparity in outcomes between patients living in close proximity to their service, compared to those in rural areas. Optimal management of diabetes, vascular perfusion and control of infection may also contribute to preventing LEA in people with active foot ulceration.  相似文献   
993.
The essential oil of Melaleuca alternifolia (tea tree) has broad-spectrum antimicrobial activity. The mechanisms of action of tea tree oil and three of its components, 1,8-cineole, terpinen-4-ol, and alpha-terpineol, against Staphylococcus aureus ATCC 9144 were investigated. Treatment with these agents at their MICs and two times their MICs, particularly treatment with terpinen-4-ol and alpha-terpineol, reduced the viability of S. aureus. None of the agents caused lysis, as determined by measurement of the optical density at 620 nm, although cells became disproportionately sensitive to subsequent autolysis. Loss of 260-nm-absorbing material occurred after treatment with concentrations equivalent to the MIC, particularly after treatment with 1,8-cineole and alpha-terpineol. S. aureus organisms treated with tea tree oil or its components at the MIC or two times the MIC showed a significant loss of tolerance to NaCl. When the agents were tested at one-half the MIC, only 1,8-cineole significantly reduced the tolerance of S. aureus to NaCl. Electron microscopy of terpinen-4-ol-treated cells showed the formation of mesosomes and the loss of cytoplasmic contents. The predisposition to lysis, the loss of 260-nm-absorbing material, the loss of tolerance to NaCl, and the altered morphology seen by electron microscopy all suggest that tea tree oil and its components compromise the cytoplasmic membrane.  相似文献   
994.
Objective: To determine perceived preparedness of Australian hospital‐based prevocational doctors for resuscitation skills and management of emergencies, and to identify differences between doctors who perceive themselves well prepared and those who perceive themselves poorly prepared for emergencies, in demographics and exposure to desired learning methods. Methods: Questionnaire consisting of a mix of graded Likert scales and free‐text answers distributed to 36 Australian hospitals for secondary distribution to hospital medical officers. Results: From 2607 questionnaires posted, 470 (18.1%) were returned. Thirty‐one per cent (95% confidence interval [CI] 26–35%) felt well prepared for resuscitation and management of emergencies, 41% (CI 37–45%) felt adequately prepared and 28% (CI 24–32%) felt they were not well prepared. Those who felt well prepared reported that they had experienced more exposure to a range of educational methods, including consultant contact, supervisor feedback, clinical skills, high fidelity simulator sessions and unit meetings. Well‐prepared and poorly prepared doctors had similar opinions of the usefulness of various learning methods, but the poorly prepared group more frequently expressed a desire for increased exposure to contact with registrars and consultants, clinical skills sessions and hospital and unit meetings. There were no differences in gender, age or country of origin (Australia vs international medical graduates) between those who felt well or poorly prepared. Conclusions: Many prevocational hospital doctors feel inadequately prepared for the management of emergencies. Perceived preparedness is associated with more exposure to particular educational activities. Increasing exposure to learning of emergencies in undergraduate and prevocational years could reduce the number of junior doctors who feel poorly prepared for emergencies.  相似文献   
995.
996.
BACKGROUND: Surgical treatment of keloid scars is associated with an approximately 70% recurrence rate at the excision site. OBJECTIVE: We sought to assess keloid recurrence rates when superficial radiation therapy (SRT) was applied following surgical excision. METHODS: Medical records were reviewed of subjects treated for keloid scars followed by SRT (SRT-100™; Sensus Healthcare, Boca Raton, Florida) using a biologically effective dose (BED) of 30Gy and for whom the required retrospective data was available. Eligible subjects (N=61) were treated for 96 keloid scars with SRT. Subjects were male (48%) and female (52%) with a mean age of 38.87 years. Subjects were treated for ≥1 keloid scars following removal by sutured excision (93%) or tangential excision with secondary intention technique (7%). Almost all subjects (98%) received BED 30Gy with irradiation scheme of three 6Gy SRT treatments on Days 1, 2 and 3 following surgery. Mean energy of 100KV (73%) or 70KV (27%) were applied. RESULTS: Ten treated keloidectomy sites (10.4%) had recurrences (i.e., presence of any new tissue growth on the surgical scar) within 12 months increasing to 11 (12.7%) at 18 months. Kaplan-Meier survival probability cure rate was 85.6% from 24 months post-SRT treatment onwards. Transient hyperpigmentation was the most frequent adverse event and there were no malignancies in the treatment area during follow-up evaluations. CONCLUSIONS: SRT with a BED value of 30 Gy delivered to keloidectomy excision sites immediately following excision was well-tolerated and resulted in markedly fewer long-term recurrences than reported following keloidectomy alone. Most keloid scar recurrences occurred within one year. There were no malignancies during follow-up evaluations.  相似文献   
997.
Although not commonly available in Canada, cryosurgery (cryoablation) for prostate cancer has been practiced in many countries. The field of cryoablation has evolved significantly over the past 30 years. Two prostate cryoablation programs were started in Canada in the early 1990s, in London, ON and Calgary, AB, focusing, respectively, on salvage therapy following radiation failure and primary local treatment. This article chronicles the development of the two programs and outlines the scientific and clinical contributions by investigators at the two centers.  相似文献   
998.
999.
In our first survey of transplant centers in March 2020, >75% of kidney and liver programs were either suspended or operating under restrictions. To safely resume transplantation, we must understand the evolving impact of COVID-19 on transplant recipients and center-level practices. We therefore conducted a six-week follow-up survey May 7-15, 2020, and linked responses to the COVID-19 incidence map, with a response rate of 84%. Suspension of live donor transplantation decreased from 72% in March to 30% in May for kidneys and from 68% to 52% for livers. Restrictions/suspension of deceased donor transplantation decreased from 84% to 58% for kidneys and from 73% to 42% for livers. Resuming transplantation at normal capacity was envisioned by 83% of programs by August 2020. Exclusively using local recovery teams for deceased donor procurement was reported by 28%. Respondents reported caring for a total of 1166 COVID-19–positive transplant recipients; 25% were critically ill. Telemedicine challenges were reported by 81%. There was a lack of consensus regarding management of potential living donors or candidates with SARS-CoV-2. Our findings demonstrate persistent heterogeneity in center-level response to COVID-19 even as transplant activity resumes, making ongoing national data collection and real-time analysis critical to inform best practices.  相似文献   
1000.
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