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Hamid R Djalilian Khashayar Lessan Vahid Grami Stefan E Pambuccian Stephen R Spellman Walter C Low Walter A Hall Frank G Ondrey 《Otolaryngology--head and neck surgery》2004,131(5):781-783
OBJECTIVES: To develop an immune-competent animal model for mucosally derived squamous cell carcinoma (SCCA). STUDY DESIGN: Fifteen Fischer 344 rats were inoculated with 1, 2, 5, 10, or 20 x 10(6) FAT7 cells in their flanks. The animals were observed for tumor growth and metastasis. RESULTS: All animals developed tumors that grew exponentially. Pulmonary metastases developed in all animals and 13% developed lymph node metastases. CONCLUSION: The FAT7 flank tumor in Fischer 344 rats is a new animal model that closely resembles the behavior of human mucosal head and neck cancer. SIGNIFICANCE: The existence of an immune-competent, mucosally derived, and reliable animal model of SCCA that somewhat resembles human head and neck SCCA gives the opportunity to perform immune-modulating experiments on head and neck cancer in these animals. EBM rating: B-3. 相似文献
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Organ preservation and reperfusion injury have significant detrimental effects on both short- and long-term organ function. Ischemia reperfusion injury (IRI) underlies organ transplant dysfunction, myocardial infarction, stroke, and shock. Multiple molecular pathways are engaged in reactive oxygen production, apoptosis, signaling, and tissue regeneration. There has been an increased understanding of the important role of immune and inflammatory pathways in IRI, both in humans and in experimental models. Both cellular and soluble components of the immune system are directly activated during IRI, and there is evidence that immune mediators directly contribute to organ dysfunction. Immune activation during IRI likely underlies the enhanced immunogenicity of ischemic organs, with resultant increased rejection and fibrosis. Novel human therapies targeting T and B cells for classic immune diseases can now be considered to prevent and treat IRI. Organ preservation injury and cold ischemia could well have distinct pathophysiology from warm IRI and represent an opportunity to develop improved preservation methods. 相似文献
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INTRODUCTION: Broncholithiasis is often seen after chronic granulomatous diseases such as tuberculosis and hystoplasmosis and leads to a wide spectrum of signs and symptoms; including hemoptysis which often needs surgical management. The goal of this study is evaluation of surgery in patients with tuberculous broncholithiasis who present with hemoptysis. MATERIALS AND METHODS: In this study all patients with tuberculous broncholithiasis had been operated on between 1991 and 2005, followed up at least 6 months and at most 9 years, and studied relating to age, sex, clinical symptoms, diagnostic methods, type of surgical treatment, complications and mortality. RESULTS: Overall 5 patients have been studied (male:female=2:3, mean=31 years); 2 with severe and 3 mild to moderate and recurring hemoptysis, lesion at left in 80% and at right in 1, in 3 patients some degree of bronchiectasia was seen, in 4 the lesion was visible in bronchoscopy and endoscopic removal of the lesion failed in all. Three of patients underwent pulmonary resections and in 2 broncholithotomy has been done. In follow-up, patients treated with pulmonary resection have had no subsequent problems, but in patients treated with broncholithotomy due to occurring late bronchiectasia, re-operation and pulmonary resection was inavoidable. There was no mortality. CONCLUSION: Regarding the dangers of hemoptysis and excellent results of surgery and possible occurance of late bronchiectasia after broncholithotomy, the results of our study show that pulmonary resection distal to the lesion and as the retention of lung of parenchyma is preferable. Broncholithotomy should be done only in patients in whom pulmonary resection is not technically possible. Because of the very low occurance of this complication complete studies are needed. 相似文献
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Whole-heart cine MRI using real-time respiratory self-gating. 总被引:1,自引:0,他引:1
Sergio Uribe Vivek Muthurangu Redha Boubertakh Tobias Schaeffter Reza Razavi Derek L G Hill Michael S Hansen 《Magnetic resonance in medicine》2007,57(3):606-613
Two-dimensional (2D) breath-hold cine MRI is used to assess cardiac anatomy and function. However, this technique requires cooperation from the patient, and in some cases the scan planning is complicated. Isotropic nonangulated three-dimensional (3D) cardiac MR can overcome some of these problems because it requires minimal planning and can be reformatted in any plane. However, current methods, even those that use undersampling techniques, involve breath-holding for periods that are too long for many patients. Free-breathing respiratory gating sequences represent a possible solution for realizing 3D cine imaging. A real-time respiratory self-gating technique for whole-heart cine MRI is presented. The technique enables assessment of cardiac anatomy and function with minimum planning or patient cooperation. Nonangulated isotropic 3D data were acquired from five healthy volunteers and then reformatted into 2D clinical views. The respiratory self-gating technique is shown to improve image quality in free-breathing scanning. In addition, ventricular volumetric data obtained using the 3D approach were comparable to those acquired with the conventional multislice 2D approach. 相似文献
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James D Fogarty Jason M Hafron David M Hoenig Reza Ghavamian 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(2):199-204
OBJECTIVES: Nephron-sparing surgery has emerged as the treatment of choice for the incidentally detected small renal mass, especially those less than 4 cm in size. We describe our technique and experience with the laparoscopic excision of these lesions. METHODS: Between June 2001 and October 2003, 20 patients underwent nephron-sparing surgery at our institution. Twenty-one laparoscopic partial nephrectomy procedures were performed. All tumors were detected incidentally by cross-sectional imaging. All patients had a solid renal mass or a complex cystic renal mass of Bosniak category III or greater. All solid tumors were exophytic and less than 4cm in diameter. Both transperitoneal and retroperitoneal approaches were used. Hemostasis was achieved without hilar control in 20 of the 21 cases. RESULTS: Twenty renal units were approached transperitoneally, and 1 retroperitoneally. Mean tumor size was 2.6 cm (range, 1.2 to 4). Mean estimated blood loss was 211 mL (range, 50 to 500), and mean operative time was 165 minutes. Pathology revealed renal cell carcinoma in 14 (70%). No intraoperative complications occurred. Two patients required blood transfusions postoperatively. CONCLUSION: Carefully selected patients with small, exophytic renal masses can safely undergo laparoscopic excision. When achievable, this procedure can be a more logical alternative to ablative techniques for the minimally invasive management of such lesions. 相似文献
39.
Magnetically-labeled sensitized splenocytes to identify glioma by MRI: a preliminary study. 总被引:1,自引:0,他引:1
Ali S Arbab Ali M Rad A S M Iskander Kourosh Jafari-Khouzani Stephen L Brown Jamie L Churchman Guangliang Ding Quan Jiang Joseph A Frank Hamid Soltanian-Zadeh Donald J Peck 《Magnetic resonance in medicine》2007,58(3):519-526
This study investigated the feasibility of imaging the migration and incorporation of magnetically-labeled sensitized splenocytes in an experimental 9L glioma brain tumor model. Splenocytes collected from tumor-bearing (sensitized splenocytes) or control (nonsensitized splenocytes) host rats were analyzed to determine the population of different cells, labeled with ferumoxides-protamine sulfate (FePro) and injected intravenously to recipient rats (N=4, for each group) bearing intracranial 9L tumors. Day 3 postinjection of splenocytes multiecho T2*-weighted and three-dimensional (3D) gradient echo MRI were obtained using a 7 Tesla MR system. R2* (1/T2*) maps were created from the T2*-weighted images. Signal intensities (SIs) and R2* values in the tumors and contralateral brain were determined by hand drawn regions of interest (ROIs). Brain sections were stained for the evidence of administered cells. Both 3D and T2*-weighted MRI showed low signal intensity areas in and around the tumors in rats that received labeled sensitized splenocytes. Prussian blue (PB), CD45- and CD8-positive cells were present in areas at the corresponding sites of low signal intensities seen on MRI. Rats that received labeled nonsensitized splenocytes did not show low signal intensity areas or PB positive cells in or around the implanted tumors. In conclusion, the immunogenic reaction can be exploited to delineate recurrent glioma using MRI following systemically delivered magnetically labeled sensitized splenocytes or T-cells. 相似文献
40.
Accelerating cardiac cine 3D imaging using k-t BLAST. 总被引:1,自引:0,他引:1
Sebastian Kozerke Jeffrey Tsao Reza Razavi Peter Boesiger 《Magnetic resonance in medicine》2004,52(1):19-26
By exploiting spatiotemporal correlations in cardiac acquisitions using k-t BLAST, gated cine 3D acquisitions of the heart were accelerated by a net factor of 4.3, making single breathhold acquisitions possible. Sparse sampling of k-t space along a sheared grid pattern was implemented into a cine 3D SSFP sequence. The acquisition of low-resolution training data, which was required to resolve aliasing in the k-t BLAST method, was either interleaved into the sampling process or obtained in a separate prescan to allow for shorter breathhold durations in patients with heart disease. Volumetric datasets covering the heart with 20 slices at a spatial resolution of 2 x 2 x 5 mm3 were recorded with 20 cardiac phases in a total breathhold duration of 25-27 sec, or 18 sec if partial Fourier sampling was additionally employed. The feasibility of the method was demonstrated on healthy volunteers and on patients. The comparison of endocardial area derived from single slices of the 3D dataset with values extracted from separate single-slice acquisitions showed no significant differences. By shortening the acquisition substantially, k-t BLAST may greatly facilitate volumetric imaging of the heart for evaluation of regional wall motion and the assessment of ventricular volume and ejection fraction. 相似文献