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991.
992.
Gastroesophageal reflux disease in lung transplant recipients   总被引:3,自引:0,他引:3  
BACKGROUND: Chronic allograft dysfunction after lung transplantation contributes to poor long-term survival. A link between gastric aspiration and post-transplant lung dysfunction has been suggested, but little is known about the significance of gastroesophageal reflux disease (GERD) after lung transplantation. METHODS: A retrospective study was performed to determine the prevalence of GERD in lung transplant recipients. Patients who underwent lung transplantation at Duke University, survived at least 6 months and had post-transplant 24-h pH studies were included in the analysis. Antireflux medications were discontinued prior to the pH study. Demographic data, pH study date and results, FEV1 at the time of the pH study, confirmed acute rejection episodes, and current medications were collected. The FEV1 ratio was calculated at the time of pH study (current FEV1/best post-transplant FEV1). RESULTS: Forty-three patients met entry criteria. Studies were performed at a median of 558 d post-transplant. Thirty of forty-three (69.8%) patients tested had abnormal total acid contact times (normal: <5%). The mean acid contact times for all patients were 10% total, 11.8% upright and 7.9% supine. A negative correlation was found between total or upright acid reflux and FEV1 ratio at the time of studies (-0.341 and -0.419; p = 0.025 and p = 0.005, respectively). The effect of acid reflux on FEV1 ratio remained significant after multivariable analysis. CONCLUSIONS: There is a high prevalence of GERD among selected lung transplant recipients who had pH studies performed and its presence is associated with worse pulmonary function. Future studies are needed to assess whether GERD contributes to the pathogenesis of bronchiolitis obliterans syndrome (BOS).  相似文献   
993.
Comparison of autograft and allograft aortic valve replacement in children   总被引:3,自引:0,他引:3  
OBJECTIVE: This study was undertaken to compare the clinical and hemodynamic results following aortic valve replacement with a pulmonary valve autograft (Ross procedure) or an allograft valve in children. METHODS: The records of 107 pediatric aortic valve replacements from 1994 through 2001 were reviewed, including 78 autografts and 25 allografts. Four mechanical aortic valve replacements performed during this period were excluded from analysis. RESULTS: There were 3 perioperative deaths and 1 late death. Reoperations were required in 5 autograft recipients (with autograft preservation in 4) and in 3 allograft recipients (all requiring valve re-replacement). Seven-year survival (96% in both groups) and reoperation-free survival (88% in the autograft group; 73% in the allograft group, P =.5) were not significantly different. Serial echocardiographic studies showed that in the autograft group, left ventricular outflow tract maximal velocity (2.0-1.8 m/s, P =.02) and left ventricular thickness (10.1-8.4 mm, P <.0001) fell significantly. In the allograft group, maximal velocity (2.3-3.0 m/s, P =.03) increased significantly and left ventricular thickness (9.5-9.0 mm, P =.2) showed minimal change. Analysis according to preoperative physiology (aortic stenosis versus insufficiency), congenital cardiac anatomy, number or type of previous operations, age of patient, and use of balloon valvotomy did not predict outcomes. CONCLUSIONS: Aortic valve replacement with either the autograft or allograft provides excellent clinical results in children during an intermediate duration of observation. The Ross procedure achieves a superior hemodynamic result, which may be clinically important with longer follow-up.  相似文献   
994.
995.

INTRODUCTION

Schwannomas that arise within the muscle plane are called intramuscular schwannomas. The low incidence of these tumours and the lack of specific clinical features make preoperative diagnosis difficult. Herein, we report our experience with intramuscular schwannomas. We present details of the clinical presentation, radiological diagnosis and management of these tumours.

METHODS

Between January 2011 and December 2013, 29 patients were diagnosed and treated for histologically proven schwannoma at the National University Hospital, Singapore. Among these 29 patients, eight (five male, three female) had intramuscular schwannomas.

RESULTS

The mean age of the eight patients was 40 (range 27–57) years. The most common presenting feature was a palpable mass. The mean interval between surgical treatment and the onset of clinical symptoms was 17.1 (range 4–72) months. Six of the eight tumours (75.0%) were located in the lower limb, while 2 (25.0%) were located in the upper limb. None of the patients had any preoperative neurological deficits. Tinel’s sign was present in one patient. Magnetic resonance (MR) imaging showed that the findings of split-fat sign, low signal margin and fascicular sign were present in all patients. The entry and exit sign was observed in 4 (50.0%) patients, a hyperintense rim was observed in 7 (87.5%) patients and the target sign was observed in 5 (62.5%) patients. All patients underwent microsurgical excision of the tumour and none developed any postoperative neurological deficits.

CONCLUSION

Intramuscular schwannomas demonstrate the findings of split-fat sign, low signal margin and fascicular sign on MR imaging. These findings are useful for the radiological diagnosis of intramuscular schwannoma.  相似文献   
996.
目的探讨增强CT扫描与MRI在肝癌诊断中的价值。方法回顾性分析2014年5月至2016年3月在本院进行影像检查并经手术病理确认的60例肝癌患者的临床资料和影像资料,同时对患者癌变部进行归类分析,并通过两种影像检查方法的确诊率来评判两种检查方式的价值。结果60例中,巨块型占总数,结节型占总数54.5%,小肝癌例数占总数30.3%。增强CT对肝癌患者的总检出率为91.2%,MRI对肝癌患者的总检出率为92.3%。两者无明显统计学差异。结论在肝癌的确诊方面,MRI和增强CT扫描均具有较高的精度,可以作进一步推广应用。  相似文献   
997.
Background Extending the length of the Roux limb (RL) in gastric bypass (GBP) may improve weight loss in super obese patients (body mass index [BMI] > 50 kg/m2), but no consensus exists about the optimal length of the RL. We sought to determine the impact of RL length on weight loss in super obese patients 1 year after GBP. Materials and Methods One-year weight loss outcomes were analyzed in all super obese patients who underwent consecutive and primary laparoscopic or open GBP between January 2003 and June 2006. Patients were divided into two groups according to RL length (100 vs. 150 cm). The RL length was at the discretion of the attending surgeon. Baseline and follow-up data were collected prospectively. Multiple linear regression was used to adjust for potential confounders in the weight loss outcomes. Results Twelve-month follow-up data were available in 137 (85%) of 161 patients with a BMI ≥ 50 who underwent GBP during the study period. An RL of 100 or 150 cm was used in 102 (74.5%) and 35 patients (25.5%), respectively. In multivariate analysis, patients with the 150-cm RL lost more weight (68.5 vs. 55.3 kg, p < 0.01), had a greater change in BMI (25 vs. 21 kg/m2, p = 0.01), and had greater excess weight loss (64 vs. 53%, p < 0.01). Conclusion A 150-cm RL provides better weight loss outcomes in super obese patients at 1-year follow-up.  相似文献   
998.
BACKGROUND: Failure of cancer immunotherapy is essentially due to immunological tolerance to tumor-associated antigens (TAAs), as these antigens are also expressed in healthy tissues. METHODS: Here, we used transgenic adenocarcinoma of mouse prostate (TRAMP) mice, which develop lethal prostate cancer due to prostate-specific expression of SV40 T antigen (Tag), to evaluate effects of prostatic transformation on oncogene TAA-specific tolerance and to test the possibility of breaking such tolerance using a modified recombinant vaccinia virus. RESULTS: We showed that Tag expression in TRAMP mice is uniquely extra-thymic, and levels of prostatic Tag expression positively correlate with malignant transformation of the prostate. Yet, young tumor-free TRAMP mice were tolerant to Tag antigen. We therefore attempted overcoming such peripheral oncogene-specific T cell tolerance through immunization with a vaccinia construct encoding Tag immunogenic epitopes. This vaccination modality showed that oncogene-specific tolerance was successfully overcome by effective in vivo priming of Tag-specific cytotoxic T cells (CTLs). However, this was restricted to young TRAMP mice. Tag-specific CTL from "tumor na?ve" young TRAMP mice showed significant anti-tumor efficacy in vivo by eliminating established heterotopic prostate tumors and prolonging survival in SCID mice harboring Tag-expressing tumors. In contrast, older TRAMP mice with established prostate tumors exhibited oncogene-specific tolerance as evidenced by failure to generate Tag-specific CTL following Tag-specific immunization. CONCLUSIONS: Peripheral tolerance can be overcome for effective anti-tumor therapy following oncogene-specific immunization. However, this ability to elicit oncogene-specific CTL is impeded in the tumor-bearing host, in the context of increased oncogene expression associated with tumor progression.  相似文献   
999.
We present a case of bilateral intrathoracic kidneys and adrenal glands associated with bilateral posterior diaphragmatic defects in a symptomatic 18-month-old baby boy. The diaphragmatic defect did not appear to be the typical posterolateral diaphragmatic hernia of Bochdalek. The patient underwent primary surgical correction through an abdominal approach. Postoperatively, the patient enjoyed an uneventful course and was discharged home without any further events. We discuss this report of bilateral intrathoracic kidneys associated with bilateral diaphragmatic hernias, we describe the operative management, and we analyze the possible embryological development of this defect.  相似文献   
1000.
Diagnosis of basaloid squamous carcinoma (BSCC) currently relies mainly on histological criteria, with variable immunohistochemical results reported in small series. We explored the use of a battery of immunohistochemical stains to elucidate this diagnosis on 45 cases of BSCC. To further elucidate the immunohistochemical profile of BSCC, to explore potential genetic pathways of malignant transformation using proliferation markers, and to investigate a possible link with Human Papillomavirus (HPV). Forty-five cases of BSCC and 34 site-matched cases of squamous cell carcinoma (SCC) were obtained from the archives of the pathology department at our institution. Extensive literature review was undertaken utilizing Medline. Ber-EP4 is a useful diagnostic marker for BSCC, positive in 82% (37/45) of the cases and in 68% (23/34) of SCC. An alternative is the combination of cytokeratins CK14 and CK7, known to be negative, and CK1, known to be positive, which achieves an accuracy of 73% (33/45) in BSCC and 88% (30/34) in SCC. The two diagnostic approaches were in agreement in 66% of the cases; both methods were equally accurate in the divergent cases. Increased expression of the proliferation markers supports the concept that BSCC is a rapidly growing tumor. Results of p16 stains support an etiological link between BSCC and HPV; interestingly, HPV was present significantly more in BSCC (71% (32/45)), than in SCC (59% (20/34)) in this study (P = 0.02). This data has been presented, in abstract form, at the 2008 United States and Canadian Academy of Pathology Annual Meeting, March 4, in Denver, Colorado.  相似文献   
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