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BACKGROUND: Hematopoiesis outside the bone marrow is known to occur in patients with severe anemia, leukemia, polycythemia, or myelofibrosis, and in patients affected by chronic poisoning by marrow-toxic substances. CASE DESCRIPTION: A 66-year-old right-handed man complained of 4 days of terrible right-sided, sharp, and shooting headache for which he saw his primary care provider. Routine laboratory examination showed a WBC count of 30800/microL. Neuroimaging showed a large, right frontotemporal, extra-axial, heterogeneously enhancing, dural based mass with associated recent intramural hemorrhage with evidence of midline shift and uncal herniation. The mass was resected using a right-sided extended craniotomy with anterior fossa and middle fossa approach. A hematoxylin-eosin-stained biopsy specimen showed whorls of tumor cells, diagnostic of a meningioma. Interspersed within the tumor bulk were nucleated RBCs, representing areas of extramedullary erythropoiesis within a meningioma. Flow cytometric evaluation confirmed the clinical suspicion of an underlying chronic lymphocytic leukemia. CONCLUSION: Occurrence of extramedullary hematopoiesis within a meningioma is extremely rare. Various theories may explain the occurrence of extramedullary hematopoiesis occurring within a meningioma in our patient, such as hematopoietic differentiation of multipotent mesenchymal tumor cells; direct extension of hematopoietic activity from the neighboring marrow cavity; displacement from bone marrow of stem cells that settle and develop in tissues where capillaries and blood vessels proliferate, such as a meningioma; or congenital heterotopia of totipotent connective tissue cells, which, under certain circumstances, may transform into hematopoietic tissue.  相似文献   
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The migration of the medical staff represents an increasingly worring reason for romanian health policy-makers. According to the Ministry of Health, in 2009 year, the human resources indicators pointed out 26.5 physicians/ 10,000 inhabitants (whereas the European Union average was 32.8) and 60.4 nurses and midwives (whereas the European Union average was 108.5). Between 2007-2010, over 9000 physicians requested professional certificates in order to practice abroad and the majority have left the country. This phenomenon is related to the Romania's entrance in European Union and it is supposed to continue in the coming years. The direct consequences of the migration of the medical staff consist of significant differences between the country's regions in the health workforce distribution, the most affected by the critical shortage of health service providers being the North-Eastern region, especially in rural area. In order to limit the migration phenomenon, the Ministry of Health elaborated some strategies and workforce policies on medium and long-term, but the results will be difficult to assess.  相似文献   
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INTRODUCTION: Immune system activation and oxidative stress are involved in the pathogenesis of heart failure (HF). We aimed to test the hypothesis that upgrading from right ventricular pacing (RVp) to biventricular pacing (BiVp) can counteract these phenomena. METHODS: 28 HF patients, with BiVp were switched to RVp for one week, and then returned to BiVp. Immediately prior to, and 48 h after the return to BiVp, left ventricular (LV) systolic function was evaluated by echocardiography, and serum N-terminal pro-brain natriuretic peptide (NTproBNP), C-reactive protein (CRP), tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL6), nitric oxide metabolites (NO(x)) and malondialdehyde (MDA) were assayed. RESULTS: LV systolic function significantly improved 48 h after switching from RVp to BiVp: Ao-VTI (p<0.001), SV (p<0.001) and CO (p<0.001), and mitral regurgitation significantly decreased (p=0.003). At the same time, indices of peripheral immune activation decreased: TNF-alpha (p=0.02) and IL6 (p<0.001). MDA decreased (p<0.001), whereas NO(x) increased (p=0.04). NTproBNP and CRP did not change. In addition, in "responders" (i.e. CO increase >10% during BiVp vs. RVp) NTproBNP decreased and NO(x) increased. However, during BiVp, the decreases in TNF-alpha, IL6, and MDA occurred both in responders and in non-responders and were accompanied by a reduction in mitral regurgitation. CONCLUSION: The beneficial effect of BiVp compared to RVp extends beyond improving cardiac haemodynamics and comprises a decrease in immune activation accompanied by an increase in serum NO(x) and decrease in serum MDA.  相似文献   
176.
BACKGROUND: Technological advances in military equipment have resulted in more devices being mounted on the helmet to enhance the capability of the soldier. The soldier's neck must bear this head-supported mass (HSM) and the resulting dynamic characteristics of the head and neck system are changed. The purpose of this study was to vary the conditions of impact as well as the design criteria to quantify the effect of HSM on neck injury risk through computational modeling. METHODS: The TNO MADYMO detailed neck model was used for a matrix of 196 simulations designed to vary the impact conditions and HSM properties added to the model. These parameters included seven impact directions, three impact magnitudes, nine mass locations, and three mass magnitudes. The data collected from these simulations were evaluated for injury risk using the lower neck beam criterion equation. RESULTS: The results from these simulations provide detailed information regarding the risk of injury based on a particular HSM configuration and the acceleration of the body. The predominant factor in increasing risk in the lower neck is the increase in pulse magnitude. The effect of pulse magnitude is more dominant in the directions that create a flexion or lateral bending moment. CONCLUSION: HSM increases the level of injury, but the impact level that the subject is exposed to is a more dominating factor in determining injury risk.  相似文献   
177.
Image-guided helical Tomotherapy for treatment of spine tumors   总被引:1,自引:0,他引:1  
OBJECTIVES: One of the most common indications for radiotherapy is treatment of the spine. The vast majority of cases are related to metastatic disease with primary tumors of the spine being rare. Conventional radiation therapy often plays an important role in the management of spine tumors although at times with significant side effects and disadvantages. Furthermore, retreatment of spine tumors is a challenge due to concerns over spinal cord toxicity. In this series, we examine the efficacy of using image-guided helical Tomotherapy and the possible advantages offered by this new technology. PATIENTS AND METHODS: Eight patients at Hoag Memorial Hospital Presbyterian were treated between November 2005 and November 2006. The median age was 66 years. Of the eight patients, seven had metastatic disease with one patient having a primary neuroendocrine tumor of the spine. Five patients were previously treated to the spine with conventional radiation planning. Two patients received single fraction stereotactic radiosurgery (15 Gy) while the remaining patients received hypofractionated stereotactic radiotherapy to a median total dose of 2,500 cGy in 500 cGy fractions. RESULTS: At the time of last follow-up, radiographic control was seen in all eight patients with a median local control rate of 2.5 months (range of 1-5.8 months). Four of the eight patients are still alive with median overall survival of 5.1 months (range 1.4-6.9 months). Acute toxicity ranged from Radiation Therapy Oncology Group (RTOG) score 0-2 and no patients experienced late complications of radiation myelitis. CONCLUSIONS: The TomoTherapy Hi-ART system can be an alternative treatment option for upfront or retreatment of spine tumors. Minimal acute and late toxicity were seen in patients treated with Tomotherapy. Intensity-modulated radiation delivery combined with megavoltage CT image guidance offered by the TomoTherapy Hi-ART system allows for set-up and delivery accuracy that is required for stereotactic treatment of spine tumors and eliminates the need for any internal or external fiducial marker placement.  相似文献   
178.
Duma  M.-N.  Brambs  C.  Wittig  A. 《Best Practice Onkologie》2020,15(1-2):24-30
best practice onkologie - Ziel dieses Beitrags ist es, einen Überblick über neue Techniken der Strahlentherapie in der gynäkologischen Onkologie zu geben. Vorgestellt und...  相似文献   
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