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91.
92.
随机模拟是统计学研究中的一种常用方法,将其运用到医药数理统计教学中,有很好的演示效果。以Excel软件里的随机数发生器为基础,进行简单的随机模拟。通过几个例子,说明了随机模拟在教学中可以起到模拟随机试验、验证重要结论和解释重要概念等作用。  相似文献   
93.
An increased biological effect is realized when hyperthermia and radiation therapy are combined simultaneously. To take advantage of this effect, techniques have been developed that combine existing hyperthermia devices with a linear accelerator. This allows concomitant delivery of either ultrasound or microwave hyperthermia with photon radiation therapy. Two techniques have been used clinically: the orthogonal technique, in which the microwave or ultrasound beam and the radiation beam are orthogonal to one another, and the en face technique, in which the ultrasound or microwave beam and the radiation beam travel into the tumour through the same treatment window. The en face technique has necessitated the development of special attachments so that the hyperthermia device can be mounted to the linear accelerator and so that non-uniform portions of the hyperthermia device can be removed from the radiation beam. For microwave therapy, applicators are mounted onto the linear accelerator using the compensating filter tray holder. For ultrasound, special reflector devices are mounted to a frame that is mounted onto the compensating filter tray holder of the linear accelerator. Because the linear accelerator is an isocentric device, the height of the radiation source is fixed, and this has necessitated specially designed devices so that the ultrasound support system is compatible with the linear accelerator. The treatment setups for both the en face technique and the orthogonal technique require the interaction of both hyperthermia and radiation therapy personnel and equipment. The dosimetry and day-to-day operations for each technique are unique. The simulation for the en face technique is much different from the simulation of a normal radiation treatment and requires the presence of a hyperthermia physicist. Also, for the en face technique, the attenuation of the microwave applicator and the thickness and attenuation of the ultrasound reflector system are taken into account for radiation dosimetry. This paper presents details of the dosimetry and logistics of the techniques for simultaneous thermoradiotherapy based on 7 years of experience treating more than 50 patients.  相似文献   
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Aim. The objectives of this study were to evaluate an Internet education programme provided to primigravida in the third trimester of pregnancy with the aim of enhancing mothers’ knowledge about newborn care and increasing their maternal confidence. Background. Shorter hospital stays have had an impact on the traditional role of mother–baby nurses in providing education about parenting to their parturient women. Internet education is an efficient way to provide nursing instruction. Design. A randomised controlled trial was used. A total of 118 women receiving prenatal care in a hospital clinic who met study criteria and who consented were assigned randomly to intervention and control groups. The study was conducted at a hospital in Taiwan. Methods. The target population was women at 32–34 weeks gestation, using the Internet on a regular basis. The primigravida were randomly assigned to either the control group (n = 57) or the experimental group (n = 61). Two primary outcome measures were newborn‐care knowledge and maternal confidence. Results. The changes in newborn‐care knowledge were 7·21 for the experimental group, compared with 1·95 for the control group; the difference between the least‐squares means computed by ancova was 5·73 and statistically significant (p < 0·001). The changes in maternal confidence were 8·46 for the experimental group and 3·05 for the control group; the difference between the least‐squares means computed by ancova was 5·94 and statistically significant (p < 0·001). Conclusion. Results suggest that Internet education about newborn care may contribute to greater care knowledge and maternal confidence. Relevance to clinical practice. Internet newborn‐care education programmes can achieve success in promoting newborn care and provide health professionals with evidence‐based intervention.  相似文献   
95.
Background & AimsThe Charlson Comorbidity Index (CACI) has been suggested as a tool to determine comorbidity burden and guide management for patients with mucinous pancreatic cysts (Intrapapillary Mucinous Neoplasms and Mucinous Cystic Neoplasms), but has not been studied well among “low-risk” mucinous pancreatic cysts i.e. without worrisome features (WF) and high-risk stigmata (HRS). This study sought to determine the comorbidity burden among surveillance population of low-risk pancreatic cysts and provide their follow-up mortality outcomes.MethodsA single center study retrospectively reviewed a prospective pancreatic cyst database and included individuals with low-risk cysts undergoing serial imaging during 2016. Electronic medical records were reviewed to determine their baseline age-adjusted CACI (age-CACI). After 4 years, their progression to WF, disease specific (pancreatic malignancy-related, DSM), extra-pancreatic (EPM), and overall mortalities (OM) were determined using Kaplan-Meir Survival Analysis.Results502 individuals underwent prospective surveillance. The study included 440 individuals with low-risk suspected or presumed mucinous cysts and excluded 50 and 12 individuals with WF and HRS respectively. Over a median follow-up of 56 months, 12 WF progressions, 2 DSMs, 42 EPMs, and 44 OMs were observed. Baseline age-CACI had good predictive capacity for 4-year EPM (Area-Under Curve: 0.87; p< .0001). The median age-CACI of 4 enabled cohort stratification into Low (age-CACI <4) and High CACI (age-CACI ≥4) groups. A significantly higher OM (p< .001) was observed among the High CACI group as compared to the Low CACI group.ConclusionThrough real-time application of CACI to patient outcomes, our analysis supports incorporation of this comorbidity assessment tool in making shared surveillance decisions among low-risk pancreatic cyst population.  相似文献   
96.
BackgroundIn the SPARCL (Stroke Prevention by Aggressive Reduction in Cholesterol Levels) trial, atorvastatin was compared with placebo in 4,731 participants with recent stroke or transient ischemic attack and no known coronary heart disease. Atorvastatin reduced the first occurrence of stroke and the first occurrence of a composite of vascular events.ObjectivesThe aim of this post hoc analysis was to assess the occurrence of all (first and subsequent) vascular events and the effect of atorvastatin to reduce these events by vascular territory (cerebrovascular, coronary, or peripheral) in SPARCL.MethodsTreatment effects on total adjudicated vascular events, overall and by vascular territory, were summarized by marginal proportional hazards models. Vascular event rates were estimated for each treatment group with cumulative incidence functions.ResultsThe placebo group had an estimated 41.2 first and 62.7 total vascular events per 100 participants over 6 years. There were 164 fewer first and 390 fewer total vascular events in the atorvastatin group (total events hazard ratio: 0.68; 95% confidence interval: 0.60 to 0.77). The total events reduction included 177 fewer cerebrovascular, 170 fewer coronary, and 43 fewer peripheral events. Over 6 years, an estimated 20 vascular events per 100 participants were avoided with atorvastatin treatment.ConclusionsIn participants with recent stroke or transient ischemic attack, the total number of vascular events prevented with atorvastatin was more than twice the number of first events prevented. Total event reduction provides a comprehensive metric to capture the totality of atorvastatin clinical efficacy in reducing disease burden after stroke or transient ischemic attack. (Lipitor in the Prevention of Stroke, for Patients Who Have Had a Previous Stroke [SPARCL]; NCT00147602)  相似文献   
97.
98.
BackgroundCasirivimab and imdevimab are effective in preventing hospitalization in outpatients with coronavirus disease 2019 (COVID-19); however, disease progression after casirivimab and imdevimab administration has been reported. This study aimed to elucidate the risk factors for disease progression after casirivimab and imdevimab administration.MethodsThis retrospective study included patients with COVID-19 who received casirivimab and imdevimab at Hiroshima City Funairi Citizens Hospital between August 6, 2021, and October 10, 2021. All patients had at least one risk factor for severe disease and were treated on admission. The patients’ background characteristics and test results at the first visit were analyzed. The patients were divided into two groups (progressed and improved) based on whether they progressed to acute respiratory failure during hospitalization.ResultsSixty-seven patients were included: 9 patients in the progressed group (median age, 56 years) and 58 patients in the improved group (median age, 51 years). Age, coexistence rate of diabetes, cycle threshold value of polymerase chain reaction test, rate of detectable pneumonia on chest radiographs or chest computed tomography images, lymphocyte count, and the levels of C-reactive protein, interleukin-6, glucose, and glycated hemoglobin were significantly different between the two groups. Multivariate logistic regression analysis revealed that the coexistence of diabetes and the presence of detectable pneumonia on chest radiographs were independent factors predicting the progression to acute respiratory failure.ConclusionAcute respiratory failure after antibody therapy with casirivimab and imdevimab may develop in patients with diabetes or detectable pneumonia on chest radiographs at the first visit.  相似文献   
99.
ObjectivesThe goal of this study was to examine prognostic relationships between cardiac imaging measures and cardiovascular outcome in people living with human immunodeficiency virus (HIV) (PLWH) on highly active antiretroviral therapy (HAART).BackgroundPLWH have a higher prevalence of cardiovascular disease and heart failure (HF) compared with the noninfected population. The pathophysiological drivers of myocardial dysfunction and worse cardiovascular outcome in HIV remain poorly understood.MethodsThis prospective observational longitudinal study included consecutive PLWH on long-term HAART undergoing cardiac magnetic resonance (CMR) examination for assessment of myocardial volumes and function, T1 and T2 mapping, perfusion, and scar. Time-to-event analysis was performed from the index CMR examination to the first single event per patient. The primary endpoint was an adjudicated adverse cardiovascular event (cardiovascular mortality, nonfatal acute coronary syndrome, an appropriate device discharge, or a documented HF hospitalization).ResultsA total of 156 participants (62% male; age [median, interquartile range]: 50 years [42 to 57 years]) were included. During a median follow-up of 13 months (9 to 19 months), 24 events were observed (4 HF deaths, 1 sudden cardiac death, 2 nonfatal acute myocardial infarction, 1 appropriate device discharge, and 16 HF hospitalizations). Patients with events had higher native T1 (median [interquartile range]: 1,149 ms [1,115 to 1,163 ms] vs. 1,110 ms [1,075 to 1,138 ms]); native T2 (40 ms [38 to 41 ms] vs. 37 ms [36 to 39 ms]); left ventricular (LV) mass index (65 g/m2 [49 to 77 g/m2] vs. 57 g/m2 [49 to 64 g/m2]), and N-terminal pro–B-type natriuretic peptide (109 pg/l [25 to 337 pg/l] vs. 48 pg/l [23 to 82 pg/l]) (all p < 0.05). In multivariable analyses, native T1 was independently predictive of adverse events (chi-square test, 15.9; p < 0.001; native T1 [10 ms] hazard ratio [95% confidence interval]: 1.20 [1.08 to 1.33]; p = 0.001), followed by a model that also included LV mass (chi-square test, 17.1; p < 0.001). Traditional cardiovascular risk scores were not predictive of the adverse events.ConclusionsOur findings reveal important prognostic associations of diffuse myocardial fibrosis and LV remodeling in PLWH. These results may support development of personalized approaches to screening and early intervention to reduce the burden of HF in PLWH (International T1 Multicenter Outcome Study; NCT03749343).  相似文献   
100.
ObjectivesThe aim of this study was to evaluate the long-term outcomes of patients with acute coronary syndromes (ACS) with multivessel disease undergoing percutaneous coronary intervention (PCI).BackgroundControversy exists regarding the benefit of multivessel PCI across the spectrum of ACS.MethodsA total of 9,094 patients with ACS and multivessel disease (≥70% stenosis in 2 or more major epicardial vessels) undergoing PCI from the Alberta COAPT (Contemporary Acute Coronary Syndrome Patients Invasive Treatment Strategies) registry (April 1, 2007, to March 31, 2013) were reviewed. Comparisons were made between patients who underwent complete revascularization and those with incomplete revascularization. Complete revascularization was defined as multivessel PCI with a residual angiographic jeopardy score ≤10%. Associations between revascularization status and all-cause death or new myocardial infarction (primary composite endpoint) and all-cause death, new myocardial infarction, or repeat revascularization (secondary composite endpoint) were evaluated.ResultsOf the study cohort, 66.0% underwent complete revascularization. Compared with incomplete revascularization, the primary composite endpoint occurred less frequently with complete revascularization (event rate within 5 years 15.4% vs. 22.2%; inverse probability-weighted hazard ratio [IPW-HR]: 0.78; 95% confidence interval [CI]: 0.73 to 0.84; p < 0.0001). The secondary composite endpoint was less likely to occur with complete revascularization (event rate within 5 years 23.3% vs. 37.5%; IPW-HR: 0.61; 95% CI: 0.58 to 0.65; p < 0.0001). Complete revascularization was associated with a reduction in all-cause death (IPW-HR: 0.79; 95% CI: 0.73 to 0.86; p = 0.0004), new myocardial infarction (IPW-HR: 0.76; 95% CI: 0.69 to 0.84; p < 0.0001), and repeat revascularization (IPW-HR: 0.53; 95% CI: 0.49 to 0.57; p < 0.0001).ConclusionsResults from this large contemporary registry of patients with ACS and PCI for multivessel disease suggest that complete revascularization occurs commonly and is associated with improved clinical outcomes (including survival) within 5 years.  相似文献   
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