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Versatility of vertical rectus abdominis musculocutaneous flaps   总被引:2,自引:0,他引:2  
The purpose of the study was to demonstrate a variety of indications for the vertical rectus abdominis musculocutaneous (VRAM) flap with respect to donor-site morbidity and alternative procedures. Fifteen VRAM flaps were performed in 15 patients during a 4-year period. The average age of patients was 58 years (range, 34-76 years). Inferiorly based VRAM flaps were used for defect coverage after tumor resection and for penile reconstruction in 7 cases. Superiorly based VRAM flaps were performed in 7 cases for reconstruction of osteocutaneous defects following sternal osteomyelitis and tumor resection. Arterial and venous "supercharging" was necessary in one case. One free VRAM flap was performed in a patient suffering from an osteocutaneous defect after resection of a malignant melanoma metastasis with infiltration of the brain and skull. The reconstructive goals were achieved in all cases using VRAM flap procedures. No total flap loss occurred. Minor complications as well as abdominal wall bulging and hernias were observed in four cases. The pedicled VRAM flap provides a reliable tool for coverage of large soft-tissue defects of the chest wall, groin, hip, and perineum even in a high-risk population, in which a safe and fast forward flap procedure is the primary reconstructive goal. Arterial and/or venous supercharging may be necessary, particularly in superiorly based VRAM flaps. An inferiorly based VRAM flap is a reliable tool for phalloplasty under special circumstances. The indication for free VRAM flaps is given in rare clinical situations. Stabilization of the donor site using artificial mesh is highly recommended.  相似文献   
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Proinflammatory cytokines such as TNFα are elevated in patients with myeloproliferative neoplasms (MPN), but their contribution to disease pathogenesis is unknown. Here we reveal a central role for TNFα in promoting clonal dominance of JAK2(V617F) expressing cells in MPN. We show that JAK2(V617F) kinase regulates TNFα expression in cell lines and primary MPN cells and TNFα expression is correlated with JAK2(V617F) allele burden. In clonogenic assays, normal controls show reduced colony formation in the presence of TNFα while colony formation by JAK2(V617F)-positive progenitor cells is resistant or stimulated by exposure to TNFα. Ectopic JAK2(V617F) expression confers TNFα resistance to normal murine progenitor cells and overcomes inherent TNFα hypersensitivity of Fanconi anemia complementation group C deficient progenitors. Lastly, absence of TNFα limits clonal expansion and attenuates disease in a murine model of JAK2(V617F)-positive MPN. Altogether our data are consistent with a model where JAK2(V617F) promotes clonal selection by conferring TNFα resistance to a preneoplastic TNFα sensitive cell, while simultaneously generating a TNFα-rich environment. Mutations that confer resistance to environmental stem cell stressors are a recognized mechanism of clonal selection and leukemogenesis in bone marrow failure syndromes and our data suggest that this mechanism is also critical to clonal selection in MPN.  相似文献   
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The assumption that antidepressants may reduce suicide risk by reducing depressive symptoms is not based on data. Further, it is unclear if the retrospectively based anti-suicidal effects of lithium can be prospectively evaluated using lithium as an augmenting agent to antidepressants.To verify our hypothesis, we designed and conducted an exploratory proof of concept trial of four weeks duration using a randomized, double-blind, parallel group method. Forty patients were assigned to citalopram + lithium and 40 were assigned to citalopram + placebo. The primary dependent measures were the Sheehan-Suicidality Tracking Scale (S-STS) and the Montgomery-Asberg Depression Rating Scale (MADRS).The reduction of S-STS scores was large (43%) and twice that seen in MADRS scores (25%) among the eighty patients included in the trial. Both response (χ2 = 8.8, p < 0.01) and remission (χ2 = 4.6, p = 0.03) rates showed similar patterns.There were no significant differences in mean total S-STS change scores among patients assigned to citalopram with placebo (4.8 ± 5.1) and patients assigned to citalopram with lithium (5.1 ± 5.2). When explored further, a subgroup of the patients assigned to citalopram and lithium achieved therapeutic serum levels and had significantly higher S-STS remission rates (45% compared to 19%, p < 0.05).There were no deaths by suicide or other causes indicating that trials enrolling acutely suicidal patients are feasible. These results suggest that citalopram may have a direct therapeutic effect on suicidal thoughts and behaviors. Further, lithium when used in therapeutic doses may augment such effects. These data warrant further exploration of lithium and an antidepressant combination for anti-suicidal effects.  相似文献   
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De novo cholangiocarcinoma associated with recurrent primary sclerosing cholangitis in the transplanted liver is rare. This case report reviews the literature and highlights the need to consider cholangiocarcinoma in transplanted patients with PSC that clinically/biochemically deteriorate.  相似文献   
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The Symphony study showed superior 1‐year kidney graft outcome in patients on immunosuppression with tacrolimus/mycophenolate mofetil (Tacr/MMF). To analyze whether differences in clinical outcome between maintenance regimens may be explained by their impact on clinically relevant immune parameters, we assessed CD4 helper activity, immunoglobulin‐secreting cell (ISC) formation, neopterin, sCD30, and intracellular cytokine production in a prospective study in 77 renal transplant recipients treated with cyclosporine A/azathioprine (CsA/Aza), CsA/MMF, Tacr/Aza or Tacr/MMF at 2 years post‐transplant. Tacr‐ compared with CsA‐based immunosuppression was independently associated with increased IL‐2 (P < 0.0001, CD4 cells; P = 0.014, CD8 cells) and CD4 cell IL‐4 responses (P = 0.046; stepwise logistic regression) resulting in physiological responses in Tacr/Aza patients as compared with 25 healthy controls. MMF versus Aza treatment was proven to be an independent variable associated with suppression of CD4 cell IL‐10 responses (P = 0.008), B‐cell IL‐6R expression (P < 0.0001) and ISC formation [P = 0.020, staphylococcus cowan strain I (SAC I); P = 0.021, pokeweed mitogen (PWM)]. Our data suggest that Tacr/MMF had the most effective impact on graft protective Th2 responses (enhanced CD4 cell IL‐4 by Tacr, decreased CD4 cell IL‐10 responses by MMF) and suppression of B‐cell functions (MMF), whereas Tacr/Aza was associated with physiological IL‐2 and IL‐4 and stronger humoral responses which may reduce the risk of infectious disease complications. (ClinicalTrials.gov number: NCT00150891).  相似文献   
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Objectives: Concern for driving safety has prompted research into understanding factors related to performance. Brake reaction speed (BRS), the speed with which persons react to a sudden change in driving conditions, is a measure of performance. Our aim is to determine the visual, cognitive, and physical factors predicting BRS in a population sample of 1425 older drivers. Methods: The Maryland Department of Motor Vehicles roster of persons aged 67–87 and residing in Salisbury, MD, was used for recruitment of the study population. Procedures included the following: habitual, binocular visual acuity using ETDRS charts, contrast sensitivity using a Pelli-Robson chart, visual fields assessed with a 81-point screening Humphrey field at a single intensity threshold, and a questionnaire to ascertain medical conditions. Cognitive status was assessed using a standard battery of tests for attention, memory, visuo-spatial, and scanning. BRS was assessed using a computer-driven device that measured separately the initial reaction speed (IRS) (from light change to red until removing foot from accelerator) and physical response speed (PRS) (removing foot from accelerator to full brake depression). Five trial times were averaged, and time was converted to speed. Results: The median brake reaction time varied from 384 to 5688 milliseconds. Age, gender, and cognition predicted total BRS, a non-informative result as there are two distinct parts to the task. Once separated, decrease in IRS was associated with low scores on cognitive factors and missing points on the visual field. A decrease in PRS was associated with having three or more physical complaints related to legs and feet, and poorer vision search. Vision was not related to PRS. Conclusion: We have demonstrated the importance of segregating the speeds for the two tasks involved in brake reaction. Only the IRS depends on vision. Persons in good physical condition may perform poorly on brake reaction tests if their vision or cognition is compromised.  相似文献   
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