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1.
Widely Metastatic Squamous Cell Carcinoma Originating from Malignant Transformation of Hypertrophic Lichen Planus in a 24‐Year‐Old Woman: Case Report and Review of the Literature
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Lana X. Tong B.A. Matthew J. Weinstock M.D. Reed Drews M.D. Caroline C. Kim M.D. 《Pediatric dermatology》2015,32(3):e98-e101
Hypertrophic lichen planus (HLP) is a T‐cell‐mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24‐year‐old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated. 相似文献
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Radiofrequency-ablation of unresectable primary and secondary liver tumors: results in 88 patients 总被引:5,自引:0,他引:5
Philipp Hildebrand Markus Kleemann Uwe J. Roblick Lutz Mirow Matthias Birth Thorsten Leibecke Hans-Peter Bruch 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2006,391(2):118-123
Background and aims Radiofrequency-ablation (RFA) is increasingly used for destruction of unresectable primary and secondary liver tumors. We
report our experience in the use of RFA for the management of unresectable hepatic malignancies.
Patients and methods Between February 2000 and December 2004 we have undertaken 120 RFA procedures to ablate 426 unresectable primary or metastatic
liver tumors in 88 patients. RFA was performed via laparotomy (n=68), laparoscopy (n=9) or a percutaneous approach (n=43). Primary liver cancer was treated in seven patients (8%) and metastatic liver tumors were treated in 81 patients (92%).
All patients were followed to assess complications, treatment response and recurrence of malignant disease.
Results Procedure-related complication rate was low (3.4%). During a mean follow-up of 21.2 months, 15 patients had local tumor progression
(17%), 21 patients (23,9%) had new malignant disease and 27 patients (30.7%) died from intervention-unrelated complications
of their malignant disease. Additional liver lesions were identified in 27 (35%) of 77 cases by intraoperative ultrasound.
Thirty-six patients received simultaneous resection and RFA.
Conclusion RFA is a safe, well-tolerated and effective treatment for patients with unresectable primary and secondary liver malignancies. 相似文献
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Thorsten Grund Konrad Lehmann Nathalie Bock Aribert Rothenberger Gertraud Teuchert-Noodt 《Behavioral and brain functions : BBF》2006,2(1):2-14
Methylphenidate (MPH) is the most commonly used drug to treat attention deficit/hyperactivity disorder (ADHD) in children
effectively and safely. In spite of its widespread application throughout one of the most plastic and sensitive phases of
brain development, very little is known to date about its long-term effects on brain structure and function. Hence, this short
review updates the influence of MPH on brain development, since recent human and animal studies suggest that MPH alters the
dopaminergic system with long-term effects beyond the termination of treatment. 相似文献
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Dr. med. Thorsten Schäfer Heike Vogelsang 《Somnologie - Schlafforschung und Schlafmedizin》2002,6(2):79-84
Summary Question of the study Nasal continuous positive airway pressure (CPAP) prevents collapse of the upper airway during sleep in patients with obstructive sleep apnea provided that a positive transmural pressure can be maintained during inspiration. We examined pressure-flow characteristics in seven CPAP and bilevel devices during spontaneous breathing.
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H2 O) and adapted to a pneumotachograph using a standard CPAP hose and an outlet valve. We continuously measured flow, volume and pressure during resting ventilation and increasing voluntary hyperventilation and analysed the dependence of the variables on a breath-to-breath basis.
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献
Methods The CPAP devices were set to a pressure level of 9.8 hPa (10 cm H
Results Mean CPAP pressures differed between the devices (9.9 – 10.6 hPa) despite the same settings. In all machines pressure fell during inspiration to 8.4 – 9.8 hPa and increased during expiration to 11.1 – 11.7 hPa. This effect increased with higher flow rates. Maximum expiratory pressures rose to 12 – 19 hPa at peak flow rates of 2 l/s, mean expiratory pressures to 9.5 – 16 hPa. Inspiratory pressures dropped to 8.5 – 4.5 hPa (minimum) and 10.5 – 6.0 (mean). Bilevel devices showed a higher stability than CPAP devices. Pressure swings during the respiratory cycle increased the additional work of breathing.
Conclusions Due to differences in mean and effective CPAP levels CPAP devices are not simply exchangeable but should be individually adapted. Patients with higher minute ventilation might benefit from more stable CPAP machines. The impact on patients' compliance remains to be evaluated. 相似文献
9.
Association of human polyomavirus JC with peripheral blood of immunoimpaired and healthy individuals
Drries Kristina Sbiera Silviu Drews Klaus Arendt Gabriele Eggers Christian Drries Rdiger 《Journal of neurovirology》2003,9(1):81-87
JC virus (JCV) infection is regularly asymptomatic in healthy individuals. In contrast, in immunocompromised individuals, highly activated virus replication may lead to PML. Peripheral blood cells (PBCs) are found to habor JCV DNA in healthy and diseased individuals and it is discussed that they might be responsible for dissemination of the virus to the central nervous system (CNS) during persistence. To better understand the role of JCV DNA in PBCs for persistent infection and pathogenesis, the authors characterized the extent of JCV infection in Ficoll-gradient purified blood cells (peripheral blood mononuclear cells [PBMCs]) of healthy and human immunodeficiency virus type 1 (HIV-1)-infected individuals. Virus activation in PBMCs from healthy JCV-infected individuals was found at a rate of 0% to 38% at low polymerase chain reaction (PCR) sensitivity. In progressive multifocal leukoencephalopathy (PML) patients, a stronger signal was found, indicating increased virus activation. JCV DNA was regularly detected in T and B lymphocytes and in monocytes at low levels. However, granulocytes were shown to be the predominant reservoir of JCV DNA harboring high copy numbers. Although the overall distribution of viral genomes holds true for the population studied, in the individual, a markedly changed pattern of distribution can be found. 相似文献
10.
T. A. Drews K. G. Lamping D. E. Laughlin W. P. Dole 《Medical & biological engineering & computing》1987,25(4):420-427
Although present sonomicrometer techniques for measuring continuous changes in vascular diameter are very useful, two problems
with available methods are difficulty in maintaining crystal alignment throughout an acute experiment and inability to measure
absolute dimensions less than 1 mm. We have designed and ultrasonic dimension gauge system to over come these problems. The
design uses a gate to pass a 20 MHz signal to a counter during the sonic travel time between crystals, and then converts the
digital count to an analogue voltage. Interference from the transmitting impulse in the received signal was minimised using
MOSFET transistors allowing measurements of absolute dimensions from 0.00 mm to 99.9 mm. An averaging effect which depends
upon the asynchrony between the basic timer and the counter clock results in a resolution of at least 10 μm. Repeated calibration
curves showed an accuracy of 2.5 μm without significant bias. Piezoelectric crystals were mounted to a lighweight stainless-steel
clip to facilitate attachment to the vessel and to maintain the crystals in focus during changes in diameter. Mean and phasic
diameters measured in the femoral artery with the clip device correlated well with measurements obtained with crystals sewn
to the adventitia of the femoral artery of the dog (slope =0.97, r=0.99). 相似文献