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51.
52.
Epstein–Barr virus (EBV) reactivation is a very common and potentially lethal complication of renal transplantation. However, its risk factors and effects on transplant outcome are not well known. Here, we have analysed a large, multi-centre cohort (N = 512) in which 18.4% of the patients experienced EBV reactivation during the first post-transplant year. The patients were characterized pre-transplant and two weeks post-transplant by a multi-level biomarker panel. EBV reactivation was episodic for most patients, only 12 patients showed prolonged viraemia for over four months. Pre-transplant EBV shedding and male sex were associated with significantly increased incidence of post-transplant EBV reactivation. Importantly, we also identified a significant association of post-transplant EBV with acute rejection and with decreased haemoglobin levels. No further severe complications associated with EBV, either episodic or chronic, could be detected. Our data suggest that despite relatively frequent EBV reactivation, it had no association with serious complications during the first post-transplantation year. EBV shedding prior to transplantation could be employed as biomarkers for personalized immunosuppressive therapy. In summary, our results support the employed immunosuppressive regimes as relatively safe with regard to EBV. However, long-term studies are paramount to support these conclusions.  相似文献   
53.
BackgroundIncreasing cancer incidence among children alongside improved treatments has resulted in a growing number of pediatric cancer survivors. Despite childhood cancer survivors’ exposure to various factors that compromise kidney function, few studies have investigated the association between childhood cancer and future kidney disease.MethodsTo assess the risk of ESKD among childhood cancer survivors, we conducted a nationwide, population-based, retrospective cohort study that encompassed all Israeli adolescents evaluated for mandatory military service from 1967 to 1997. After obtaining detailed histories, we divided the cohort into three groups: participants without a history of tumors, those with a history of a benign tumor (nonmalignant tumor with functional impairment), and those with a history of malignancy (excluding kidney cancer). This database was linked to the Israeli ESKD registry to identify incident ESKD cases. We used Cox proportional hazards models to estimate the hazard ratio (HR) of ESKD.ResultsOf the 1,468,600 participants in the cohort, 1,444,345 had no history of tumors, 23,282 had a history of a benign tumor, and 973 had a history of malignancy. During a mean follow-up of 30.3 years, 2416 (0.2%) participants without a history of tumors developed ESKD. Although a history of benign tumors was not associated with an increased ESKD risk, participants with a history of malignancy exhibited a substantially elevated risk for ESKD compared with participants lacking a history of tumors, after controlling for age, sex, enrollment period, and paternal origin (adjusted HR, 3.2; 95% confidence interval, 1.3 to 7.7).ConclusionsChildhood cancer is associated with an increased risk for ESKD, suggesting the need for tighter and longer nephrological follow-up.  相似文献   
54.
Background ContextSmartphone-based applications enable new prospects to monitor symptoms and assess functional outcome in patients with lumbar degenerative spinal disorders. However, little is known regarding patient acceptance and preference towards new modes of digital objective outcome assessment.PurposeTo assess patient preference of an objective smartphone-based outcome measure compared to conventional paper-based subjective methods of outcome assessment.Study designProspective observational cohort study.Patient sampleFourty-nine consecutive patients undergoing surgery for lumbar degenerative spinal disorder.Outcome measuresPatients completed a preference survey to assess different methods of outcome assessment. A 5-level Likert scale ranged from strong disagreement (2 points) over neutral (6 points) to strong agreement (10 points) was used.MethodsPatients self-determined their objective functional impairment using the 6-minute Walking Test application (6WT-app) and completed a set of paper-based patient-reported outcome measures (PROMs) before and 6 weeks after surgery. Patients were then asked to rate the methods of outcome assessment in terms of suitability, convenience, and responsiveness to their symptoms.ResultsThe majority of patients considered the 6WT-app a suitable instrument (median 8.0, interquartile range [IQR] 4.0). Patients found the 6WT more convenient (median 10.0, IQR 2.0) than the Zurich Claudication Questionnaire (ZCQ; median 8.0, IQR 4.0, p=.019) and Core Outcome Measure Index (COMI; median 8.0, IQR 4.0, p=.007). There was good agreement that the 6WT-app detects change in physical performance (8.0, IQR 4.0). 78 % of patients considered the 6WT superior in detecting differences in symptoms (vs. 22% for PROMs). Seventy-six percent of patients would select the 6WT over the other, 18% the ZCQ and 6% the COMI. Eighty-two percent of patients indicated their preference to use a smartphone app for the assessment and monitoring of their spine-related symptoms in the future.ConclusionsPatients included in this study favored the smartphone-based evaluation of objective functional impairment over paper-based PROMs. Involving patients more actively by means of digital technology may increase patient compliance and satisfaction as well as diagnostic accuracy.  相似文献   
55.
This article describes policy processes that have led to the re-organisation of stroke care in the Czech Republic since 2011, which has been part of a broader process of care concentration in several medical fields. Currently, stroke care is provided by 13 Comprehensive and 32 Primary Stroke Centres. The paper explains factors that supported the reform implementation, reviews implications, and discusses future challenges.Mandatory reporting of quality indicators, the introduction of a benchmarking system, integration with pre-hospital emergency care, and the introduction of countrywide patient triage have supported more timely treatment for stroke patients and better quality of care. Data from the Stroke Care Quality Indicators of the Czech Stroke Society show positive trends in many areas: the number of patients treated with intravenous thrombolysis quadrupled in eight years, with 26.4 % of all acute stroke patients receiving thrombolysis in 2018. Czech Republic now ranks third in Europe in the number of thrombolysis per population and second in the number of mechanical thrombectomies per population. The Czech experience provides an example of positive outcomes of concentrated stroke care, while highlighting the importance of proper implementation processes. In particular, it is essential to involve stakeholders and to provide reputational incentives through continuous benchmarking.  相似文献   
56.
This paper provides guidance for researchers with some mathematical background on the conduct of time‐to‐event analysis in observational studies based on intensity (hazard) models. Discussions of basic concepts like time axis, event definition and censoring are given. Hazard models are introduced, with special emphasis on the Cox proportional hazards regression model. We provide check lists that may be useful both when fitting the model and assessing its goodness of fit and when interpreting the results. Special attention is paid to how to avoid problems with immortal time bias by introducing time‐dependent covariates. We discuss prediction based on hazard models and difficulties when attempting to draw proper causal conclusions from such models. Finally, we present a series of examples where the methods and check lists are exemplified. Computational details and implementation using the freely available R software are documented in Supplementary Material. The paper was prepared as part of the STRATOS initiative.  相似文献   
57.
58.
The final depth of a necrosis resulting from burn trauma is determined within 3 days. The zone of stasis has the potential for complete regeneration or there may be ischemic influences that lead to necrosis. In our model, we examined the dermal influence of vasoconstrictors with reference to the development of burn necrosis. On the backs of New Zealand white rabbits (4.0–4.5 kg) standardized lesions were made with a heated aluminum stamp at 80°C, 14 s in duration.

The lesions were intradermal, whereby the border zone of the coagulated tissue was found in the middle two quarters of the dermis in 100% of untreated animals after 72 h. For dermal vasoconstriction epinephrine in a dose of 0.5 μg/kg/min was used.

There were two groups of seven animals each. One group received epinephrine and the dosage was dependent on the clinical state of the animal. Several cycles were administered within a 3-day period. The reduction of skin perfusion was documented by Laser–Doppler-flowmetry. After 3 days, the skin with the lesions was excised and using a hematoxylin dye, a histological examination followed. The parameter used to determine the efficacy was the thickness of the uncoagulated part of the excised dermis.

Over a period of 48 h, an average of 2.3 epinephrine cycles of average of 88 min per animal in duration resulted in an average reduction of skin diffusion of 41%. The uncoagulated part of the dermis in the epinephrine group was 28.6% average; in the control group, this was 43.5%. The statistical analysis revealed significant differences with a p-value of 0.0312 (significant, when value is less than 0.05). The test results indicate that temporary reduction of skin perfusion through external administration of vasocontrictors may lead to progression of burn necrosis in our animal model.

Clinically, this result indicates that for patients with burn injuries and systemic inflammatory response syndrome who have insufficient volume therapy, the administration of vasocontrictors may produce similar results in the injured area.  相似文献   

59.
In severely burned patients the approach to the central vein is often difficult due to concomitant edema, but also due to the fact that the skin area, where commonly used approaches are performed, is burned as well, whereas the axillary region is often not involved. In order to perform an axillary approach to the central vein as an alternative to the commonly used approaches in patients, an anatomical dissection in fresh human cadavers was carried out. Considering the anatomical landmarks which were found during dissection of the axillary region, the axillary approach to the central vein was used in 35 patients in our intensive burn care unit with unaffected axillary skin. In three cases the only complication observed was an occasional puncture of the axillary artery without major hematoma. The infection rate of the catheters was similar to the commonly used puncture sites. This approach to the central venous line in severely burned patients can be recommended.  相似文献   
60.
Phalloarteriography in the diagnosis of erectile impotence   总被引:1,自引:0,他引:1  
An angiographic method has been developed for x-ray visualization of the arteries supplying the cavernous bodies of the penis, namely, the internal iliac, internal pudendal, and penile artery and its branches (dorsal, deep, and bulbocavernous arteries). Under normal conditions the technique makes pulsations in both dorsal penile arteries palpable, and the flow rate of fluid into the cavernous bodies necessary to produce and maintain erection can be determined. The principle of the method involves artificial passive erection or semierection, during which we perform selective or semiselective arteriography of the bed supplied by the internal iliac artery, or retrograde arteriography by puncture of the dorsal artery of the penis. Thirty males complaining of more than 1 year of impotence (including 12 diabetics) were investigated, 29 by our standard technique and 1 by translumbar pelvic arteriography with retrograde arteriography of the dorsal penile artery. All patients showed severe stenosis or obliteration of the vessels supplying the cavernous bodies. There was agreement between absence of pulsation in the dorsal penile arteries and the angiographic findings. Flow rates necessary to produce erection varied from 45 to 160 ml/min, with a mean of 90 ml/min. For controls, angiographic studies were performed in 4 men with clearly psychogenic impotence, all of whom were found to have normal-appearing arteries supplying the cavernous bodies. On the basis of these findings and previously reported histological investigations, we believe that most impotence is the symptomatic and functional result of arterial disease. The arteriographic technique described allows a precise anatomical diagnosis to be made, and can indicate surgical and microsurgical correction.
Résumé Nous avons mis au point une technique d'angiographic qui visualise la vascularisatioh artérielle des corps caverneux, soit les artères iliaques internes, honteuses internes, péniennes et leurs branches dorsales, profondes et bulbocaverneuses. Dans les conditions normales, la technique permet de palper le pouls dans les artères dorsales de la verge et de mesurer, dans les corps caverneux, le débit nécessaire pour produire et maintenir une érection. Le principe de la méthode repose sur une érection ou semi-érection artificielle passive associée, soit à une artériographie sélective ou semi-sélective du territoire de l'iliaque interne, soit à une artériographie rétrograde par ponction de l'artère dorsale de la verge.Trente hommes (dont 12 diabétiques) ont été étudiés: ils présentaient tous une impuissance depuis plus d'un an. L'investigation a été faite, dans 29 cas avec notre technique standard, dans un cas par aortographie translombaire et arteriographie rétrograde de l'artère dorsale de la verge. Il existait dans tous les cas des sténoses serrées ou des oblitérations de l'arbre artériel allant aux corps caverneux. Les lésions mises en évidence par l'artériographie concordaient avec l'absence de pulsations dans les artères dorsales de la verge. Les débits nécessaires pour produire l'érection ont varié entre 45 et 160 ml/min, avec une moyenne de 90 ml/min. A titre de contrôle, des artériographies ont été faites chez 4 hommes atteints d'impuissance manifestement psychogène: chez tous, l'irrigation artérielle des corps caverneux était normale.Ces résultats, et des études histologiques antérieures, nous amènent à penser que, dans la plupart des cas, l'impuissance est la manifestation symptomatique et fonctionnelle d'une maladie artérielle. La technique d'angiographic que nous avons décrite donne un diagnostic anatomique précis et permet de poser les indications de la chirurgie ou de la microchirurgie correctrice.
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