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41.
According to the guidelines on early cancer detection measures of the German Federal Joint Committee exploration of the medical history and physical examination of the penis and testes as well as digital rectal examination are recommended in men. The interdisciplinary S3 guidelines on prostate cancer recommend that for early detection of prostate cancer the combination of digital rectal examination and prostate-specific-antigen determination should always be offered for well-informed men. Data on prostate cancer screening suggest a significant reduction of tumor-specific mortality. The results of the ERSPC study revealed a number needed to screen (NNS) of 357 and a number needed to treat of 23 to prevent 1 man dying from metastatic prostate cancer. The G?teborg study with a median follow-up of 14 years even shows a NNS of 293 and 12 men needed to be diagnosed to prevent 1 prostate cancer death. Thus, PSA-based early detection reduces the rate of cancer-specific mortality by 31-56%. In contrast insufficient data exist to allow a risk-benefit analysis of screening for kidney cancer, transitional cell carcinoma of the bladder or upper urinary tract as well as for testicular cancer.  相似文献   
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Bevacizumab has been reported to cause diffusion restriction in the tumor bed of patients with malignant gliomas. This study evaluated prolonged diffusion restriction, in the corpus callosum (CC), of patients with malignant brain tumors treated with bevacizumab. We retrospectively reviewed our database of patients treated with bevacizumab for malignant brain tumors looking for those with restricted diffusion in the CC. CC ADC ratio measurements were obtained prior to and following treatment. Correlation was made with biopsy (n = 3) and MR perfusion (n = 7) and PET (n = 4). The temporal evolution of these changes relative to therapy was examined with mixed effects regression analysis. Nine patients (eight malignant gliomas, one malignant meningioma) out of 146 patients were found to have developed areas of diffusion restriction in the CC. These areas tended to enlarge and coalesce over serial MRIs and persisted for up to 22 months. Hypoperfusion was demonstrated in MR perfusion in 7/7. PET was hypometabolic in all 4. Biopsy of the CC showed no tumor in 3/3. ADC ratio measurements indicated a significant overall effect of time (F(16,60) = 11.2; p < 0.0001), consistent with persistent diffusion restriction over the measured time periods. Bevacizumab causes prolonged diffusion restriction in the CC. The negative MR perfusion, FDG PET and histopathology suggest this is a toxicity of bevacizumab and not active tumor. Awareness of these changes can assist in patient care.  相似文献   
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BackgroundNonbacterial thrombotic endocarditis, or marantic endocarditis, is rare. Contemporary data on the etiology, echocardiographic evaluation, and management of nonbacterial thrombotic endocarditis are limited.MethodsA single-center retrospective cohort study was performed. Electronic medical records and echocardiographic records were searched for patients ages ≥18 years with a confirmed diagnosis of nonbacterial thrombotic endocarditis between January 1999 and November 2019. Demographic, echocardiographic, and management data were collected.ResultsOf 600,577 transthoracic echocardiograms (TTEs) and 89,264 transesophageal echocardiograms (TEEs), 42 patients had nonbacterial thrombotic endocarditis (mean age: 54 ± 14.5 years; 66.7% were female). The median duration of follow-up was 8.2 (interquartile range 3.3-24.4) months. Seventeen patients (40.5%) had malignancy, 33.3% had systemic lupus erythematosus, and 35.7% had antiphospholipid antibody syndrome. Stroke was the most common presentation (59.5%).TTE enabled the diagnosis in 19 cases (45.2%), compared with TEE, which identified the condition in 33 of 34 (97.1%) cases in which it was utilized. Three-dimensional echocardiography was performed in 17 TEEs. The most common valves involved were mitral (61.9%), and aortic (23.8%) valves. Thirty-two patients were managed with anticoagulation. Ten patients underwent surgery. Sixteen (38.1%) patients died, most of whom had a diagnosis of advanced malignancy.ConclusionIn a contemporary 20-year cohort, TTE and TEE played important roles in diagnosis, with superior diagnostic performance of TEE for nonbacterial thrombotic endocarditis. Mortality was high, and advanced malignancy portended a worse prognosis. Management in most cases was therapeutic anticoagulation. In select cases, surgery provided favorable outcomes.  相似文献   
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Allocation of deceased donor kidneys is based on several criteria; however, the final decision to accept or reject the offered kidney is made by the potential recipient's transplant team (surgeon/nephrologist). Several considerations including assessment of the donor quality, the HLA match between the donor and the recipient, several recipient factors, the geographical location of the recipient, and the organ all affect the decision of whether or not to finally accept the organ for a particular recipient. This decision needs to be made quickly, often on the spot. Maximizing the benefit from this scarce resource raises difficult ethical issues. The philosophies of equity and utility are often competing. This article will discuss the several considerations for the pediatric nephrologist while accepting a deceased donor kidney for a particular pediatric patient.  相似文献   
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Background: QT dispersion, measured as interlead variability of QT intervals in the surface electrocardiogram, has been demonstrated to provide an indirect measurement of the inhomogeneity of myocardial repolarization as a potential substrate for ventricular arrhythmias. Methods: QT dispersion was measured in the standard 12-lead ECG in 51 patients at the time of implantation of a third generation implantable cardioverter defibrillator (ICD) with automatic electrogram storage capability for electrical events triggering device therapy. In addition, QT dispersion was measured in 100 age- and sex-matched healthy controls. All 5 1 study patients with ICD were prospectively followed to determine possible associations between QT dispersion at implant and subsequent spontaneous ICD shocks for ventricular tachyarrhythmias (VT). Results: Rate-corrected QT dispersion and adjusted QTc dispersion, which takes account of the number of leads measured, were significantly greater in ICD patients compared to controls (76 ± 25 ms vs 46 ± 11 ms, and 24 ± 7 ms vs 14 ± 3 ms respectively, P < 0.0 1). During 15 ± 8 months follow-up, ventricular tachyarrhythmias occurred in 23 (45%) of 51 ICD patients. QTc dispersion and adjusted QTc dispersion were not significantly different between ICD patients with ventricular tachyarrhythmias and ICD patients without ventricular tachyarrhythmias during follow-up (74 ± 19 ms versus 77 ± 29 ms, and 23 ± 6 ms vs 25 ± 8 ms respectively). Conclusion: Increased QT dispersion measured in the 12-lead standard ECG does not appear to be a useful marker for future arrhythmic events in a mixed patient population with ICD.  相似文献   
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Purpose

To evaluate whether ultrasmall superparamagnetic iron oxide nanoparticle (USPIO)-enhanced magnetic resonance imaging (MRI) can detect allograft rejection in pediatric kidney transplant patients.

Procedures

The USPIO ferumoxytol has a long blood half-life and is phagocytosed by macrophages. In an IRB-approved single-center prospective clinical trial, 26 pediatric patients and adolescents (age 10–26 years) with acute allograft rejection (n = 5), non-rejecting allografts (n = 13), and normal native kidneys (n = 8) underwent multi-echo T2* fast spoiled gradient-echo (FSPGR) MRI after intravenous injection (p.i.) of 5 mg Fe/kg ferumoxytol. T2* relaxation times at 4 h p.i. (perfusion phase) and more than 20 h p.i. (macrophage phase) were compared with biopsy results. The presence of rejection was assessed using the Banff criteria, and the prevalence of macrophages on CD163 immunostains was determined based on a semi-quantitative scoring system. MRI and histology data were compared among patient groups using t tests, analysis of variance, and regression analyses with a significance threshold of p < 0.05.

Results

At 4 h p.i., mean T2* values were 6.6 ± 1.5 ms for native kidneys and 3.9 ms for one allograft undergoing acute immune rejection. Surprisingly, at 20–24 h p.i., one rejecting allograft showed significantly prolonged T2* relaxation times (37.0 ms) compared to native kidneys (6.3 ± 1.7 ms) and non-rejecting allografts (7.6 ± 0.1 ms). Likewise, three additional rejecting allografts showed significantly prolonged T2* relaxation times compared to non-rejecting allografts at later post-contrast time points, 25–97 h p.i. (p = 0.008). Histological analysis revealed edema and compressed microvessels in biopsies of rejecting allografts. Allografts with and without rejection showed insignificant differences in macrophage content on histopathology (p = 0.44).

Conclusion

After ferumoxytol administration, renal allografts undergoing acute rejection show prolonged T2* values compared to non-rejecting allografts. Since histology revealed no significant differences in macrophage content, the increasing T2* value is likely due to the combined effect of reduced perfusion and increased edema in rejecting allografts.
  相似文献   
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