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Pancreatic transplant imaging   总被引:1,自引:0,他引:1  
Forty-four clinical episodes of suspected (pancreas) transplant rejection in 17 pancreatic transplantation patients were reviewed retrospectively. The clinical impression of acute graft rejection, chronic rejection, or nonrejection in each episode was correlated with the results of 19 nuclear medicine, 12 ultrasound (US), and 44 magnetic resonance (MR) imaging studies. US was found to be a moderately sensitive (82%) method of detecting graft rejection. US also was effective in identifying intra- and peripancreatic fluid accumulations. Nuclear medicine imaging was also a sensitive technique (86%) and the only modality that provided physiologic information regarding graft perfusion. MR imaging allowed correct prediction of the presence or absence of graft rejection in 39 of 44 cases (sensitivity, 100%; specificity, 76%) and was an effective means of detecting pathologic fluid collections. Nuclear medicine, US, and MR imaging are all believed to be sensitive methods of detecting graft rejection and are complementary adjuncts to the clinical evaluation of pancreatic transplants.  相似文献   
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长期以来,一直存在抗高血压药物是否有致癌作用的争议.自从在年龄>50岁的妇女中使用萝芙碱提取物造成乳腺癌发病率增加的报道后[1],这一争议已持续了30年.Sipahi和同事们最近的研究显示:血管紧张素受体拮抗剂(angiotensin receptor-blockers,ARB)有较高的致癌风险.这一发现再次引发了抗...  相似文献   
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BACKGROUND:Serogroup B Neisseria meningitidis (MenB) has always been a major cause of invasive meningococcal disease (IMD) in Canada. With the successful implementation of a meningitis C conjugate vaccine, the majority of IMD in Canada is now caused by MenB.OBJECTIVE:To investigate IMD case isolates in Atlantic Canada from 2009 to 2013. Data were analyzed to determine the potential coverage of the newly licensed MenB vaccine.METHODS:Serogroup, serotype and serosubtype antigens were determined from IMD case isolates. Clonal analysis was performed using multilocus sequence typing. The protein-based vaccine antigen genes were sequenced and the predicted peptides were investigated.RESULTS:The majority of the IMD isolates were MenB (82.5%, 33 of 40) and, in particular, sequence type (ST)-154 B:4:P1.4 was responsible for 47.5% (19 of 40) of all IMD case isolates in Atlantic Canada. Isolates of this clone expressed the PorA antigen P1.4 and possessed the nhba genes encoding for Neisseria heparin-binding antigen peptide 2, which together matched exactly with two of the four components of the new four-component meningococcal B vaccine. Nineteen MenB isolates had two antigenic matches, another five MenB and one meningitis Y isolate had one antigenic match. This provided 75.8% (25 of 33) potential coverage for MenB, or a 62.5% (25 of 40) overall potential coverage for IMD.CONCLUSION:From 2009 to 2013, IMD in Atlantic Canada was mainly caused by MenB and, in particular, the B:4:P1.4 ST-154 clone, which accounted for 47.5% of all IMD case isolates. The new four-component meningococcal B vaccine appeared to offer adequate coverage against MenB in Atlantic Canada.  相似文献   
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Akagawa  KS; Takasuka  N; Nozaki  Y; Komuro  I; Azuma  M; Ueda  M; Naito  M; Takahashi  K 《Blood》1996,88(10):4029-4039
We previously showed that granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF) stimulate the differentiation of human monocytes into two phenotypically distinct types of macrophages. However, in vivo, not only CSF but also many other cytokines are produced under various conditions. Those cytokines may modulate the differentiation of monocytes by CSFs. In the present study, we showed that CD14+ adherent human monocytes can differentiate into CD1+relB+ dendritic cells (DC) by the combination of GM-CSF plus interleukin-4 (IL-4) and that they differentiate into tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like multinucleated giant cells (MGC) by the combination of M-CSF plus IL-4. However, the monocyte-derived DC were not terminally differentiated cells; they could still convert to macrophages in response to M-CSF. Tumor necrosis factor-alpha (TNF-alpha) stimulated the terminal differentiation of the DC by downregulating the expression of the M-CSF receptor, cfms mRNA, and aborting the potential to convert to macrophages. In contrast to IL-4, interferon-gamma (IFN-gamma) had no demonstrable effect on the differentiation of monocytes. Rather, IFN- gamma antagonized the effect of IL-4 and suppressed the DC and MGC formation induced by GM-CSF + IL-4 and M-CSF + IL-4, respectively. Taken together, these results provide a new aspect to our knowledge of monocyte differentiation and provide evidence that human monocytes are flexible in their differentiation potential and are precursors not only of macrophages but also of CD1+relB+DC and TRAP-positive MGC. Such a diverse pathway of monocyte differentiation may constitute one of the basic mechanisms of immune regulation.  相似文献   
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