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排序方式: 共有605条查询结果,搜索用时 23 毫秒
1.
Studies have shown a high correlation between measurements of bone mineral density (BMD) obtained on differentdual-energy X-ray absorptiometry machines. Challenger osteodensitometers (Diagnostic Medical System [DMS],Montpellier, France) are becoming widely used but little is known about their clinical performance. The aim of this study was to compare BMD measurements and the resulting patient classification based on T-scores obtained on a DMS Challenger device to those obtained on Hologic 4500A (Bedford, MA) device. Fifty-three volunteers were studied.The BMD of the spine and of the hip were simultaneously measured on both densitometers. BMD values obtained on the Challenger were significantly higher than those obtained with the Hologic QDR4500 (p<0.001). The correlations coefficients between the Hologic QDR4500 and the DMS Challenger measured BMDs were r=0.70 at the femoral neck, r=0.70 at the trochanter, and r=0.83 at the spine (p<0.001). Among the 35 postmenopausal women, there was discordance in the WHO T-score-based classification in 28 subjects (80%) at the spine, 18 subjects (52%) at the femoral neck, and 14 subjects (42%) at the trochanter. The intermachine agreement was low: The kappa score was -0.10 at the spine, 0.2 at the femoral neck, and 0.3 at the trochanter. In conclusion, this study cautions against the use of non established densitometers that leads to underdiagnosis of patients and, subsequently, to inappropriate treatment strategies.  相似文献   
2.
Venous thrombosis is rare in children. It can be either acquired or of constitutional origin. Thrombosis during non-Hodgkin lymphoma remains exceptional and is usually locally associated to the tumoral process, raising the issue of its tumoral or cruoric nature. The treatment is based on anticoagulation concomitantly to chemotherapy. We report on a 4-year-old boy admitted for mediastinal non-Hodgkin lymphoma, who developed a thrombosis of the superior vena cava associated to protein S-deficiency. The mechanism of thrombosis may have been multifactorial: associated protein S-deficiency, vascular compression, tumoral process and chemotherapy.  相似文献   
3.
The WIMSD4 code was used to calculate the fast neutron flux spectrum and the fast neutron fission cross-sections for (238)U, using six energy groups ranging from 0.5 to 10 MeV. These results, with the measured radioactivities of the (140)Ba, (131)I, (103)Ru, (95)Zr and (97)Zr fission products emerging from the fission of the (238)U foil covered with a cadmium filter, were used to measure the fast neutron flux in the Syrian Miniature Neutron Source Reactor inner irradiation site.  相似文献   
4.
Dermatofibrosarcoma protuberans is a rare entity. Due to its high propensity for local recurrence, knowledge of the appropriate management, both surgical and medical, is important for optimal patient outcomes.  相似文献   
5.
Posterior reversible encephalopathy syndrome is a rare underestimated condition, that generally complicates a rise in blood pressure in an acute setting. This entity has been increasingly identified in patients with systemic lupus erythematosus disease. PRES is challenging to diagnose seeing as it presents with nonspecific neurological symptoms, such as head-aches, confusion, seizures, visual changes or a coma, and can mimic neuropsychiatric lupus. Imaging plays a necessary role in confirming this diagnosis, as it is characterized by vasogenic edema of the posterior white matter, in which the distribution is bilateral and symmetrical. Although this syndrome is rare, early diagnosis allows a prompt treatment and therefore a favorable outcome. We present a case report of PRES in a 14-year-old female previously diagnosed with lupus nephropathy, who presented to the emergency department with seizures and uncontrolled hypertension, that was unfortunately not reversible is this patient.  相似文献   
6.
Cyclosporine A is one of the most widely used drugs in organ transplant and oncology patients. But its use is accompanied by many toxicities. This study aimed to investigate the possible protective effect of Costus afer (C. afer) leaf extract on cyclosporine A-induced testicular toxicity. This study was carried out on 40 adult male Wistar rats were divided into four groups: control, C. afer, cyclosporine A and cyclosporine A+ C. afer groups. The investigations include genital weight, sperm count and characters, serum luteinising hormone (LH) and testosterone, testicular tissue contents of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) and lipid peroxidation (MDA). Besides, a histopathological examination of testicular tissue stained with haematoxylin and eosin (H & E) was performed. Cyclosporine A+ C. afer group showed a significant increase in the genital weight, serum testosterone, sperm count, motility and viability. Besides, the extract significantly decreased testicular content of MDA and increased SOD, CAT and GSHPx. C. afer coadministration significantly decreased serum LH and sperm abnormalities and protected against testicular histopathological alterations. The extract showed a protective effect against testicular toxicity associated with cyclosporine A and that was through an antioxidant mechanism.  相似文献   
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Despite the advent of drug-eluting stents and dual antiplatelet therapy in the interventional management of cardiovascular disease, restenosis rates remain high with significant sequelae. Endovascular brachytherapy—popular in the 1990s and early 2000s—has recently resurfaced as a cost-effective treatment option. In this work, we outline the history of endovascular brachytherapy starting with its earliest promise in the 1990s. We discuss the development of drug-eluting stents and dual antiplatelet strategies and their impact on the perceived benefit of endovascular brachytherapy. For the contemporary era, we propose novel roles for endovascular brachytherapy in complex coronary artery disease and in high-risk patients managed with drug-eluting stents. We discuss the impetus for reducing the requirement and duration of dual antiplatelet therapy using endovascular brachytherapy. We also review innovative opportunities for endovascular brachytherapy after bare-metal stent placement in both coronary and noncoronary territories and offer economic arguments in favor of endovascular brachytherapy. Trials of endovascular brachytherapy in these regimes are merited.  相似文献   
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