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31.
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Coronary artery perforation is a known complication of percutaneous coronary intervention and potentially life threatening. Normally, these perforations are small and localized. We report the successful surgical management of a coronary artery perforation following stent insertion with extrusion of an 8-cm endarterectomy length of the circumflex coronary artery with a brief review of the recent literature.  相似文献   
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The loss of Gimap5 (GTPase of the immune-associated protein 5) gene function is the underlying cause of lymphopenia and autoimmune diabetes in the BioBreeding (BB) rat. The in vivo function of murine gimap5 is largely unknown. We show that selective gene ablation of the mouse gimap5 gene impairs the final intrathymic maturation of CD8 and CD4 T cells and compromises the survival of postthymic CD4 and CD8 cells, replicating findings in the BB rat model. In addition, gimap5 deficiency imposes a block of natural killer (NK)- and NKT-cell differentiation. Development of NK/NKT cells is restored on transfer of gimap5(-/-) bone marrow into a wild-type environment. Mice lacking gimap5 have a median survival of 15 weeks, exhibit chronic hepatic hematopoiesis, and in later stages show pronounced hepatocyte apoptosis, leading to liver failure. This pathology persists in a Rag2-deficient background in the absence of mature B, T, or NK cells and cannot be adoptively transferred by transplanting gimap5(-/-) bone marrow into wild-type recipients. We conclude that mouse gimap5 is necessary for the survival of peripheral T cells, NK/NKT-cell development, and the maintenance of normal liver function. These functions involve cell-intrinsic as well as cell-extrinsic mechanisms.  相似文献   
35.
The recommended operative management of unruptured sinus of Valsalva aneurysm consists of closure of the mouth of the aneurysm with or without aortic valve surgery. We report a case of unruptured aneurysm producing right ventricular outflow tract obstruction. Closure of the mouth of the aneurysm failed to relieve the obstruction, which was subsequently achieved by excising the aneurysmal wall overlying the outflow tract.  相似文献   
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In order to assess the effects of free or resin-bound bile acids on colonic topography, adult rats were surgically provided with an indwelling infusion catheter in the proximal cecum, which exited at the neck behind the head. Conscious, unrestrained rats were allowed chowad libitum and were administered 1 ml of an infusion mixture twice daily for five days. The infusion mixtures included either carrier saline, 100 mg cholestyramine, 165 μmol mixed bile acids, or the bile acids bound to cholestyramine. Additional groups of rats were fed defined diets with and without 2% cholestyramine. Compared to fed controls, colonic infusions of saline had little effect on colon topography. Infusions of 100 mg of cholestyramine in saline twice each day did cause some apparent damage to surface morphology of the colon, but not to the extent observed during feeding of the resin as 2% of the diet. In contrast, extensive surface damage of the colon was observed by twice daily infusions of either 165 μmol of an equimolar mixture of cholic, deoxycholic, and chenodeoxycholic acids, or by the bile acids mixed previously with the ion-exchange resin. The data suggest that topographical damage of the colon observed during feeding of bile acid-sequestering resins is in large part due to increased concentrations of either bound or unbound bile acids in the large bowel.  相似文献   
38.
Virus Genes - The genus Megalocytivirus includes viruses known to cause significant disease in aquacultured fish stocks. Herein, we report the complete genome sequences of two megalocytiviruses...  相似文献   
39.
The objective of this study was to compare the morphological and chemical composition of bone graft (BG) and coral graft (CG) as well as their osteogenic differentiation potential using rabbit mesenchymal stem cells (rMSCs) in vitro. SEM analysis of BG and CG revealed that the pores in these grafts were interconnected, and their micro-CT confirmed pore sizes in the range of 107-315 µm and 103-514 µm with a total porosity of 92% and 94%, respectively. EDS analysis indicated that the level of calcium in CG was relatively higher than that in BG. FTIR of BG and CG confirmed the presence of functional groups corresponding to carbonyl, aromatic, alkyl, and alkane groups. XRD results revealed that the phase content of the inorganic layer comprised highly crystalline form of calcium carbonate and carbon. Atomic force microscopy analysis showed CG had better surface roughness compared to BG. In addition, significantly higher levels of osteogenic differentiation markers, namely, alkaline phosphatase (ALP), Osteocalcin (OC) levels, and Osteonectin and Runx2, Integrin gene expression were detected in the CG cultures, when compared with those in the BG cultures. In conclusion, our results demonstrate that the osteogenic differentiation of rMSCs is relatively superior in coral graft than in bone graft culture system.  相似文献   
40.

Purpose

Hypoxia is an important factor influencing tumor progression and treatment efficacy. The aim of this study was to investigate the repeatability of hypoxia PET imaging with [18F]HX4 in patients with head and neck and lung cancer.

Methods

Nine patients with lung cancer and ten with head and neck cancer were included in the analysis (NCT01075399). Two sequential pretreatment [18F]HX4 PET/CT scans were acquired within 1 week. The maximal and mean standardized uptake values (SUVmax and SUVmean) were defined and the tumor-to-background ratios (TBR) were calculated. In addition, hypoxic volumes were determined as the volume of the tumor with a TBR >1.2 (HV1.2). Bland Altman analysis of the uptake parameters was performed and coefficients of repeatability were calculated. To evaluate the spatial repeatability of the uptake, the PET/CT images were registered and a voxel-wise comparison of the uptake was performed, providing a correlation coefficient.

Results

All parameters of [18F]HX4 uptake were significantly correlated between scans: SUVmax (r?=?0.958, p?<?0.001), SUVmean (r?=?0.946, p?<?0.001), TBRmax (r?=?0.962, p?<?0.001) and HV1.2 (r?=?0.995, p?<?0.001). The relative coefficients of repeatability were 15 % (SUVmean), 17 % (SUVmax) and 17 % (TBRmax). Voxel-wise analysis of the spatial uptake pattern within the tumors provided an average correlation of 0.65?±?0.14.

Conclusion

Repeated hypoxia PET scans with [18F]HX4 provide reproducible and spatially stable results in patients with head and neck cancer and patients with lung cancer. [18F]HX4 PET imaging can be used to assess the hypoxic status of tumors and has the potential to aid hypoxia-targeted treatments.
  相似文献   
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