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1.
A 63-year-old woman with an 18-year history of idiopathic thrombocytopenic purpura (ITP) was admitted with a persistent fever of unknown cause. Blood culture was positive for alpha-Streptococcus and echocardiography revealed severe mitral regurgitation and vegetation on the mitral valve. After antimicrobial therapy for six weeks, she underwent mitral valve repair using a Cosgrove ring. The platelet count increased and remained stable by perioperative treatment with intravenous high-dose gamma-globulin and platelet transfusion without steroids therapy or splenectomy. The hospital course was uneventful. Perioperative high-dose gamma-globulin therapy and platelet transfusion for the cardiac operation were useful to increase and maintain the platelet count for an ITP patient complicated with infective endocarditis.  相似文献   
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We evaluated the clinico-pathological characteristics of thirty-four cases with previous malignant tumor who was operated under thoracoscopy for pulmonary nodules. In twenty-three cases (67.6%), including 20 cases suspected metastatic pulmonary tumor before operation, thoracoscopic surgery was performed without doing the preoperative examinations for the definite diagnosis. The mean diameter of resected tumors was 13.5 mm and the definite diagnosis was determined in all cases by the intraoperative pathological diagnosis. There were 26(76.5%) cases of malignancy, including 20 cases(58.8%) of metastatic pulmonary tumor and 6 cases (17.7%) of primary lung cancer. Accuracy rate of predictive diagnosis before operation was 67.6%. From the analysis of difference between pre- and post-operative diagnoses, inflammatory nodules or tuberculoma in the solitary nodule and intrapulmonary lymph nodes or silicotic nodules in the multiple nodules should have been considered with more carefully attention. Univariate and multivariate analysis showed that patients with metastatic tumor previously was only a predictive factor for metastatic tumor. Age, gender, CT findings, the number of nodules, disease free interval and tumor markers were unreliable factors in this study. In conclusion, there were a lot of cases with previous malignant tumor in which thoracoscopic surgery could become a first choice of modalities for the diagnosis of pulmonary nodules. Early thoracoscopic procedure will be recommended for such patients to perform the immediate treatment.  相似文献   
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A 78-year-old male who had a bronchial asthma underwent coronary artery bypass grafting (CABG) using the left internal thoracic artery and the radial artery. The patient could not be weaned from the cardiopulmonary bypass because the radial artery which anastomosed to the obtuse marginal artery (OM) had a spasm after CABG. An additional bypass using a long saphenous vein to OM was carried out immediately. It brought a weaning from cardiopulmonary bypass. If the cardiac function after CABG is insufficient in patients with bronchial asthma, CABG must be re-done immediately, considering that they cause the arterial spasm more than patients without bronchial asthma.  相似文献   
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Sixteen patients who involved in chest wall disease underwent major chest wall resection between April 1995 and January 1999. The underlying diseases were 6 recurrence of breast cancers, 4 direct invasion by primary lung cancer, 2 metastatic chest wall tumor, one direct invasion by metastatic lung tumor, one direct invasion by metastatic mediastinal tumor, one radio-induced-necrosis of the chest wall, and one chest wall infection. In 9 patients, the thoracic cage reconstruction was performed using double sheets of absorbable mesh (Dexon mesh), cross string sutures and autologous ribs grafts. None of the patients had major respiratory failure and chest wall unstability. No late complications including infections, pains, recurrence and others related to reconstruction materials have been observed.  相似文献   
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Degradation of p57Kip2 mediated by SCFSkp2-dependent ubiquitylation   总被引:19,自引:0,他引:19       下载免费PDF全文
The abundance of the cyclin-dependent kinase (CDK) inhibitor p57Kip2, an important regulator of cell cycle progression, is thought to be controlled by the ubiquitin-proteasome pathway. The Skp1/Cul1/F-box (SCF)-type E3 ubiquitin ligase complex SCFSkp2 has now been shown to be responsible for regulating the cellular level of p57Kip2 by targeting it for ubiquitylation and proteolysis. The elimination of p57Kip2 was impaired in Skp2-/- cells, resulting in abnormal accumulation of the protein. Coimmunoprecipitation analysis also revealed that Skp2 interacts with p57Kip2 in vivo. Overexpression of WT Skp2 promoted degradation of p57Kip2, whereas expression of a dominant negative mutant of Skp2 prolonged the half-life of p57Kip2. Mutation of the threonine residue (Thr-310) of human p57Kip2 that is conserved between the COOH-terminal QT domains of p57Kip2 and p27Kip1 prevented the effect of Skp2 on the stability of p57Kip2, suggesting that phosphorylation at this site is required for SCFSkp2-mediated ubiquitylation. Finally, the purified recombinant SCFSkp2 complex mediated p57Kip2 ubiquitylation in vitro in a manner dependent on the presence of the cyclin E-CDK2 complex. These observations thus demonstrate that the SCFSkp2 complex plays an important role in cell-cycle progression by determining the abundance of p57Kip2 and that of the related CDK inhibitor p27Kip1.  相似文献   
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Background

Familial pancreatic cancer (FPC) is defined as a family in which at least two first-degree relatives have pancreatic cancer (PC). The prognostic significance of PC in an FPC family after surgery is not fully understood.

Methods

This was a retrospective study of 427 patients who underwent pancreatectomy for pancreatic ductal adenocarcinoma between January 2008 and December 2016. PC patients who also had at least one first-degree relative with PC were defined as FPC patients. The associations between recurrence and clinicopathological characteristics were analyzed for both FPC and non-FPC patients.

Results

FPC patients accounted for 31 of the 427 (7.3%) patients. Recurrence occurred in 72.1% of the total cohort and in 87.1% of the 31 FPC patients. Multivariate analysis showed that being an FPC patient was an independent predictor for relapse-free survival (RFS) (hazard ratio [HR] 1.52, P = 0.038). Although univariate analysis revealed that being an FPC patient was significantly associated with poorer overall survival (OS) (P < 0.001), multivariate analysis showed that being an FPC patient was not an independent predictor for OS (P = 0.164). Dichotomization of the 427 patients into those who received (n = 317: 17 FPC and 300 non-FPC patients) and did not receive (n = 110: 14 FPC and 96 non-FPC patients) adjuvant chemotherapy revealed that being an FPC patient was an independent predictor for RFS (HR 2.50, P < 0.001) and OS (HR 2.30, P = 0.003) only for patients who received adjuvant chemotherapy.

Conclusions

This study has shown that being an FPC patient is a significant prognostic indicator for PC patients who undergo resection and receive adjuvant chemotherapy.

  相似文献   
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AIM: The pathologic feature of aortic aneurysm is considered to be the remodeling of the aortic wall, involving fragmentation and decrease of elastic fibers in the tunica media. Matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9, have been implicated in collagen and elastin degeneration within the aortic wall. The precise relationship among MMPs and tissue inhibitor of metalloproteinases (TIMPs) is still unclear. We have studied the expression of MMP-2, MMP-9 tissue inhibitor of metalloprotein-1 (TIMP-1), TIMP-2 and membrane type 1-MMP (MT-1-MMP) in the wall of small AAAs (30-45 mm), large AAAs (>45 mm) and controls (<25 mm). We investigated the relationship among expressions of MMP-2, TIMP-2 and MT1-MMP in the walls. METHODS: The aortic walls in the patients with AAA were harvested from the maximum diameter, while the aortic walls in autopsy cases were harvested as controls. We analyzed tissue distribution of cell types by immunochemistry, protein expression by Western blotting and mRNA expression by competitive polymerase chain reaction. RESULTS: They consisted of 11 in controls, 8 in small AAAs and 26 in large AAAs. Among the MMPs-positive-cells, mainly macrophage, MMP-2-positive cells were in the intima, but MMP-9-positive cells in the intima and adventitia. In the small size, MMP-2 and MMP-9 mRNA were higher than those of control. In the large size, MT1-MMP and MMP-9 mRNA were higher than those of the controls. In the mRNA level of the whole AAA, significant correlations were present between MMP-2 and MMP-9, between MMP-2 and TIMP-1, and between MMP-9 and TIMP-1. These expressions were confirmed by Western blotting. CONCLUSION: We concluded as follows: 1) MMP-2 and MMP-9 may play an important role in the developmental process of AAA. 2) TIMP-1 plays an important role of interacting MMP-2 and/or MMP-9. 3) MMP-2 and MT1-MMP may play an important role in the early stages of AAAs.  相似文献   
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No reports have described experiments designed to determine the strength characteristics of spinal nerve roots and rami radiculares for the purpose of explaining the complexity of symptoms of medullary cone lesions and cauda equina syndrome. In this study, to explain the pathogenesis of cauda equina syndrome, monoaxial tensile tests were performed to determine the strength characteristics of spinal nerve roots and rami radiculares, and analysis was conducted to evaluate the stress-strain relationship and strength characteristics. Using the same tensile test device, the nerve root and ramus radiculares isolated from the spinal cords of pigs were subjected to the tensile test and stress relaxation test at load strain rates of 0.1, 1, 10, and 100 s-1 under identical settings. The tensile strength of the nerve root was not rate dependent, while the ramus radiculares tensile strength tended to decrease as the strain rate increased. These findings provide important insights into cauda equina symptoms, radiculopathy, and clinical symptoms of the medullary cone.  相似文献   
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