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61.
F.Andrew Gaffney Jui-Chin Lin Ronald M. Peshock Larry Bush L.Maximilian Buja 《The American journal of cardiology》1983,52(5):607-609
Several agents are used as echocardiographic contrast agents, but their unreliability discourages routine clinical use. Studies from the early 1960s suggest that dilute hydrogen peroxide (H2O2) is a safe intravascular agent. Its use was evaluated in contrast echocardiography. To obtain dense opacification reliably, H2O2 (3%) was passed through a sterile 0.2 μ Millipore filter and diluted with heparinized saline solution to make a 0.1 to 0.2% solution. A drop of blood was withdrawn from an indwelling peripheral venous needle into a syringe containing 0.5 to 2.0 ml of the dilute H2O2 and the contents injected. Studies in dogs, normal adults and 36 patients with noncyanotic congenital and acquired cardiac disorders produced dense opacification with no complications. In vitro mixture of H2O2 (0.3%) with leukocyte-poor blood or plasma produced only a few microbubbles, while addition to whole blood or buffy coat produced many, suggesting a role for leukocyte peroxidase. H2O2 contrast echocardiography is simple, inexpensive, and reliably provides dense, sustained opacification. This study and previous studies suggest that intravenous injection of 0.2% H2O2 can be done safely. Great caution should be exercised in patients with severe pulmonary hypertension or large right-to-left shunts because little clinical experience with H2O2 is available. 相似文献
62.
Gardiwal Ajmal; Yu Hong; Oswald Hanno; Luesebrink Ulrich; Ludwig Andreas; Pichlmaier Andreas Maximilian; Drexler Helmut; Klein Gunnar 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2008,10(3):358-363
Aims: There is increasing evidence that right ventricular (RV) pacingmay have detrimental effects by increasing morbidity and mortalityfor heart failure in implantable cardioverter–defibrillator(ICD) patients. In this study we prospectively tested the hypothesisthat cumulative RV pacing increases ventricular tachycardia/ventricularfibrillation (VT/VF) occurrence (primary endpoint) and hospitalizationand mortality for heart failure (secondary endpoint) in a predominantlysecondary prophylactic ICD patient population. Methods and results: Two hundred and fifty patients were divided into two groupsaccording to the median of cumulative RV pacing (2 vs. >2%)and prospectively followed-up for occurrence of primary andsecondary endpoints for 18 ± 4 months. Established predictorsfor VT/VF occurrence and heart failure events such as age, leftventricular ejection fraction (EF), QRS duration, history ofatrial fibrillation, and NT-proBNP were collected at enrolment.Multivariate Cox regression analysis revealed that cumulativeRV pacing > 2% and EF < 40% were independent predictorsfor VT/VF occurrence and heart failure events. Kaplan–Meieranalysis showed that patients with >2% cumulative RV pacingmore frequently suffered from VT/VF occurrence and heart failurehospitalization. Conclusion: Cumulative RV pacing > 2% and EF < 40% are independentpredictors for VT/VF occurrence and mortality and hospitalizationfor heart failure in predominantly secondary prophylactic ICDpatients. Our data show that algorithms capable of reducingcumulative RV pacing should be used more frequently in clinicalpractice. 相似文献
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64.
Luigi Villa Thilo Krüger Claudia Seikrit Anja S. Mühlfeld Uta Kunter Cornelius Werner Michael Kleines Maximilian Schulze-Hagen Michael Dreher Alexander Kersten Nikolaus Marx Jürgen Floege Thomas Rauen Gerald S. Braun 《Medicine》2021,100(10)
Chronic renal replacement therapy by either a kidney transplant (KTX) or hemodialysis (HD) predisposes patients to an increased risk for adverse outcomes of COVID-19. However, details on this interaction remain incomplete. To provide further characterization, we undertook a retrospective observational cohort analysis of the majority of the hemodialysis and renal transplant population affected by the first regional outbreak of severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) in Germany. In a region of 250,000 inhabitants we identified a total of 21 cases with SARS-CoV-2 among 100 KTX and 260 HD patients, that is, 7 KTX with COVID-19, 14 HD with COVID-19, and 3 HD with asymptomatic carrier status. As a first observation, KTX recipients exhibited trends for a higher mortality (43 vs 18%) and a higher proportion of acute respiratory distress syndrome (ARDS) (57 vs 27%) when compared to their HD counterparts. As a novel finding, development of ARDS was significantly associated with the time spent on previous renal replacement therapy (RRT), defined as the composite of dialysis time and time on the transplant (non-ARDS 4.3 vs ARDS 10.6 years, P = .016). Multivariate logistic regression analysis showed an OR of 1.7 per year of RRT. The association remained robust when analysis was confined to KTX patients (5.1 vs 13.2 years, P = .002) or when correlating the time spent on a renal transplant alone (P = .038). Similarly, longer RRT correlated with death vs survival (P = .0002). In conclusion our data suggest renal replacement vintage as a novel risk factor for COVID-19-associated ARDS and death. The findings should be validated by larger cohorts. 相似文献
65.
Marco Armbruster Sebastian Gassenmaier Mareike Haack Maximilian Reiter Dominik Nörenberg Thomas Henzler Nora N. Sommer Wieland H. Sommer Franziska Braun 《International journal of computer assisted radiology and surgery》2018,13(12):1971-1980
Purpose
To investigate whether structured reports (SRs) provide benefits regarding the completeness and the clarity of reports, as well as regarding the satisfaction of the referring physicians compared to narrative freetext reports (NRs) of MRI examinations of the petrous bone.Methods
After sample size calculation, 32 patients with clinically indicated MRI examinations of the petrous bone were included in this retrospective study. The already existing NRs were taken from the radiologic information system. The corresponding SRs were retrospectively generated by two radiologists using an online-based application. All 64 reports (one NR and one SR per patient) were evaluated by two head and neck physicians using a questionnaire.Results
While 41% of the SRs showed no missing report key feature, all NRs exhibited at least one missing key feature (p?<?0.001). SRs achieved significantly higher satisfaction rates regarding the linguistic quality and overall report quality compared to NRs: Using a 6-point Likert scale (1?=?insufficient to 6?=?excellent), SRs were rated with a median value of 6 [interquartile range (IQR): 1] for linguistic as well as overall quality, and NRs were rated with a median of 5 (IQR: 0) for linguistic as well as overall quality (p?<?0.001).Conclusions
Structured reporting of petrous bone MRI examinations may positively influence the completeness and quality of radiologic reports. Due to the easier readability and facilitation of information extraction, SRs improve the satisfaction level of the referring physicians.66.
Maximilian Petri Ingo Stoffels Klaus Griewank Jithin Jose Peter Engels Andrea Schulz Harald Pötzschke Philipp Jansen Dirk Schadendorf Joachim Dissemond Joachim Klode 《Molecular imaging and biology》2018,20(1):124-130
Purpose
Chronic leg ulcers can be a challenge to treat and long-term therapy a significant cost factor in western public health budgets. Objective wound assessment assays enabling selection of appropriate wound therapy regimes would be desirable. Oxygenation status in ulcer tissue has obtained increased attention as a relevant factor in wound healing. To increase oxygenation in wounds, a topical hemoglobin spray was developed. Although favorable results have been noted, the link between clinical efficacy and the mode of action has not been demonstrated. The aims were to determine if changes in tissue oxygenation can be measured after topical application of hemoglobin on chronic wounds and to evaluate the findings in terms of therapy strategies.Procedures
Photoacoustic imaging was used to measure the local oxygen saturation (StO2) in leg ulcers before and after hemoglobin spray treatment. Sclerosis of the leg ulcers was histopathologically graded and the change in wound size was documented in a follow-up examination.Results
Measuring 49 patients, an increase in StO2 after topical hemoglobin application from on average 66.1 to 71 % (p = 0.017) after 20 min was observed. Depending on the increase in StO2 (>10 % or <10 %) patients were stratified into a Responder and a Non-Responder group. Wound size significantly decreased in the Responder Group (p = 0.001), while no significant difference in the Non-Responder group (p = 0.950) was noted.Conclusion
Our findings suggest that the likelihood of wound healing under conservative therapy can be predicted by measuring changes in StO2 after topical hemoglobin application. This assay may reduce treatment time and costs by avoiding ineffective conservative long-term therapy.Trial Registration
German Clinical Trials Register: DRKS0000599367.
Jason N. Houle J. Michael Collins Maximilian D. Schmeiser 《American journal of public health》2015,105(9):e75-e80
Objectives. We examined the association between influenza outbreaks in 83 metropolitan areas and credit card and mortgage defaults, as measured in quarterly zip code–level credit data over the period of 2004 to 2012.Methods. We used ordinary least squares, fixed effects, and 2-stage least squares instrumental variables regression strategies to examine the relationship between influenza-related Google searches and 30-, 60-, and 90-day credit card and mortgage delinquency rates.Results. We found that a proxy for influenza outbreaks is associated with a small but statistically significant increase in credit card and mortgage default rates, net of other factors. These effects are largest for 90-day defaults, suggesting that influenza outbreaks have a disproportionate impact on vulnerable borrowers who are already behind on their payments.Conclusions. Overall, it appears there is a relationship between exogenous health shocks (such as influenza) and credit default. The results suggest that consumer finances could benefit from policies that aim to reduce the financial shocks of illness, particularly for vulnerable borrowers.Seasonal influenza is a viral airborne disease that generally spreads each fall and winter, causing an estimated 1.5 million people to get sick and 200 000 to be hospitalized in a typical year in the United States.1,2 Symptoms can range from mild and hardly distinguishable from a common cold to severe and life-threatening. Influenza accounts for at least 500 000 deaths in the United States in the past 3 decades.3For employed individuals, influenza can make attending work difficult, because of either personal illness or caring for sick household members. This generates significant costs to employers and employees. Estimates from 2007 suggest that annual influenza outbreaks lead to $16.3 billion in lost productivity and wages, and $10.4 billion in medical costs,4 although these costs vary considerably across place.5Although there is a robust literature on the economic costs of influenza, we know little about how such unexpected health shocks are associated with other aspects of the economy, such as loan defaults. We built on existing knowledge of the economic costs of influenza by examining how influenza outbreaks influence credit card and mortgage default rates in US cities.In the wake of the Great Recession, loan defaults have increased, with negative financial consequences for families.6 For loans due on a monthly basis, such as mortgages and credit cards, past-due balances and late fees accumulate each month. Three missed payments (90-day delinquent) is a signal of a loan at high risk for failure and in most states triggers legal collections processes.7In the microeconomic literature, illness is seen as a shock—an unexpected event—that can affect household income and expenses. If the shock results in a disruption to income, households will respond with shifts in consumption and expenditure patterns.8 We contend that influenza, as a health shock, has the potential to trigger loan default by constraining a family’s budget because of personal illness or caretaking burdens. Influenza may also trigger inattention to household financial management and a lack of planning for future bill payments.9–11 This may be especially problematic for borrowers who are already behind on their payments, whom we define as vulnerable borrowers. For these borrowers, who also tend to be economically vulnerable and disadvantaged in other ways,12,13 an influenza outbreak could increase the likelihood of further missed payments. A recent study supports this notion, and shows that economically vulnerable households are more likely to borrow and borrow more in the event of a health shock than less vulnerable households.14 However, this study did not examine credit default.A growing literature examines the complex and potentially multidirectional relationship between health and default.15–19 Most research examines whether defaults influence health,15,19,20 and less examines how health may have an impact on default risk.21 However, a key problem inherent in this literature is that health status is endogenous, and it is difficult if not impossible to disentangle processes of causation, selection, and reverse causation with survey data.Our interest in influenza provides us with a unique opportunity to improve causal estimates of health shocks on default. Influenza occurs to varying degrees in every city and year in the United States, and the intensity of the outbreak is an ostensibly exogenous health shock for communities. Thus, influenza outbreaks provide a natural experiment in which we use variation in influenza severity across time and place to identify the effects of a particular health shock on default. Specifically, we ask whether influenza outbreaks in US metropolitan statistical areas (MSAs) are associated with defaults from the first quarter (March) of 2004 (Q1 2004) to the second quarter (June) of 2012 (Q2 2012).We make 3 contributions with this study. First, we extended the literature on the economic costs of influenza. Second, we contributed to the literature on health shocks and default by providing a stronger test of the potential causal impacts of health shocks on loan default. Third, we considered whether effects vary across types of default, including 30-, 60-, and 90-day defaults. We predicted that influenza may have the greatest effect on borrowers who are already in default, such that the association between influenza and default should be stronger for borrowers who are farther behind. 相似文献
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69.