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101.
Background. This study was designed to determine whether overweight or obese status is independently associated with myocardial flow reserve (MFR), an established predictor of cardiovascular mortality, in a group of postmenopausal women with no previous cardiovascular disease. Postmenopausal women are the largest group of overweight and physically inactive individuals in the United States. Increased body mass index (BMI) is consistently associated with increased cardiovascular mortality in this population. Whether this is because of obesity itself or the accompanying increase in cardiovascular risk factors (CRFs) remains controversial. Methods. We examined the relationship of myocardial blood flow (MBF), coronary vascular resistance, and MFR to BMI in 60 postmenopausal women with no coronary heart disease. Subjects underwent dynamic N-13 ammonia positron emission tomography for the measurement of MBF and MFR. Baseline demographics, CRF, and hemodynamic parameters were recorded for each subject. Datasets were divided into 3 groups according to BMI: normal (18 to 24), overweight (25 to 29), and obese (≥30). Results. The overweight and obese groups showed significantly higher resting MBF and lower MFR than the normal-weight group (both P<.001), even after adjusting for CRF. A further analysis of subjects without any CRF (n=35) showed that the MFR remained significantly lower in the obese compared with normal-weight subjects (P=.05). Levels of known markers of vascular inflammation (high-sensitivity C-reactive protein and homocysteine) and high-density lipoprotein cholesterol levels correlated with declining MFR. Conclusions. These findings provide a mechanistic link between obesity and coronary heart disease in this population. This study was funded by a Veterans Health Administration MERIT Review Award. C.S.D. is on the Speaker’s Bureau at Pfizer, Inc., and has received grant support from Pfizer, Inc., Eli Lilly & Co., and the Veterans Health Administration.  相似文献   
102.
Introduction  Several studies have shown the usefulness of positron emission tomography (PET) quantification using standardised uptake values (SUV) for diagnosis and staging, prognosis and response monitoring. Many factors affect SUV, such as patient preparation procedures, scan acquisition, image reconstruction and data analysis settings, and the variability in methodology across centres prohibits exchange of SUV data. Therefore, standardisation of 2-[18F] fluoro-2-deoxy-D-glucose (FDG) PET whole body procedures is required in multi-centre trials. Methods  A protocol for standardisation of quantitative FDG whole body PET studies in the Netherlands (NL) was defined. This protocol is based on standardisation of: (1) patient preparation; (2) matching of scan statistics by prescribing dosage as function of patient weight, scan time per bed position, percentage of bed overlap and image acquisition mode (2D or 3D); (3) matching of image resolution by prescribing reconstruction settings for each type of scanner; (4) matching of data analysis procedure by defining volume of interest methods and SUV calculations and; (5) finally, a multi-centre QC procedure is defined using a 20-cm diameter phantom for verification of scanner calibration and the NEMA NU 2 2001 Image Quality phantom for verification of activity concentration recoveries (i.e., verification of image resolution and reconstruction convergence). Discussion  This paper describes a protocol for standardization of quantitative FDG whole body multi-centre PET studies. Conclusion  The protocol was successfully implemented in the Netherlands and has been approved by the Netherlands Society of Nuclear Medicine. An erratum to this article can be found at  相似文献   
103.
104.

OBJECTIVE

To evaluate, in a long‐term follow‐up of T1 high‐grade bladder cancer treated in a prospective, randomized trial, whether fluorescence diagnosis (FD) increases recurrence‐free survival (RFS) or reduces progression to muscle‐invasive stages.

PATIENTS AND METHODS

In all, 191 patients with suspected superficial bladder cancer were treated with transurethral resection under white light (WL) or with FD; 46 presented with initial T1 high‐grade BC (WL, 25; FD, 21). There were no differences in multifocality of tumours, concomitant carcinoma in situ or tumour size in either group.

RESULTS

Patients were followed for a median of 7.3 (WL) and 7.5 (FD) years to evaluate RFS. In the WL group there were 11, and in the FD group three, recurrent tumours of the same stage and grade. The RFS at 4 and 8 years was 69% and 52% in the WL, and 91% and 80% in FD group, respectively. With FD, the RFS was significantly longer according to Kaplan‐Meier analysis (P = 0.025). In the WL group, three (12%), and in the FD group four (19%) patients progressed to muscle‐invasive stages (≥ T2).

CONCLUSION

In initial T1 high‐grade bladder cancer, FD is significantly better than conventional WL transurethral resection for RFS. However, the progression rate to muscle‐invasive disease was not reduced by FD. Thus the clinical course (progression) of T1 high‐grade bladder cancer remains unaffected by FD.  相似文献   
105.
Posterior cruciate ligament (PCL) reconstruction remains a difficult procedure even in experienced hands0 because there is a lack of consensus regarding the most reliable and least technically challenging technique. The commonly used retrograde anteromedial tibial tunnel leads to excessive angulation at the posterior tibia and risks catastrophic neurovascular complications. We present a technique of drilling the transtibial PCL tunnel in an antegrade fashion through a posteromedial portal. This technique offers the advantage of an anterolateral route to reduce graft angulation, as well as drilling away from the important posterior neurovascular structures.  相似文献   
106.
Trauma und Berufskrankheit - Zusammenfassung Der Processus coronoideus ist der wichtigste knöcherne Stabilisator des Ellbogengelenks, der vordere Anteil des Lig. collaterale ulnae, welcher am...  相似文献   
107.
Allogeneic skin substitutes applied to burns patients   总被引:1,自引:0,他引:1  
Early re-surfacing of burn wounds remains the ideal but is limited by the availability of skin graft donor sites. Cultured grafts overcome these problems and autologous keratinocytes can be grown in culture and placed on a dermal substitute, but this results in delay and requires two operations. We developed an organotypic skin substitute, which achieves cover in one procedure, and have previously found allogeneic cell survival up to 2.5 years after grafting onto clean elective wounds (tattoo removal). Here, we report a short series using the same model applied to burns patients with less than 20% total body surface area affected. The skin substitutes consisted of allogeneic dermal fibroblasts embedded in a collagen gel overlain with allogeneic epidermal keratinocytes, and were grafted to patients with tangentially excised burns. A side-by-side comparison with meshed split-thickness autografts was performed. No grafts became infected. The allogeneic skin substitute showed little effective take at 1 week, and by 2 weeks only small islands of keratinocytes survived. These sites were subsequently covered with meshed split-thickness autograft, which took well. It is concluded that further development of this model is needed to overcome the hostile wound bed seen in burns patients.  相似文献   
108.
109.
The objective of this retrospective analysis was to determine the reliability of transcutaneous oxygen tension measurement (TcPO2) in predicting outcomes of diabetics who underwent hyperbaric oxygen therapy for lower extremity wounds. Six hyperbaric facilities provided TcPO2 data under several possible conditions: breathing air, breathing oxygen at sea level, and breathing oxygen in the chamber. Overall, 75.6% of the patients improved after hyperbaric oxygen therapy. Baseline sea-level air TcPO2 identified the degree of tissue hypoxia but had little statistical relationship with outcome prediction because some patients healed after hyperbaric oxygen therapy despite very low prehyperbaric TcPO2 values. Breathing oxygen at sea level was unreliable for predicting failure, but 68% reliable for predicting success after hyperbaric oxygen therapy. TcPO2 measured in chamber provides the best single discriminator between success and failure of hyperbaric oxygen therapy using a cutoff score of 200 mmHg. The reliability of in-chamber TcPO2 as an isolated measure was 74% with a positive predictive value of 58%. Better results can be obtained by combining information about sea-level air and in-chamber oxygen. A sea-level air TcPO2 < 15 mmHg combined with an in-chamber TcPO2 < 400 mmHg predicts failure of hyperbaric oxygen therapy with a reliability of 75.8% and a positive predictive value of 73.3%.  相似文献   
110.
OBJECTIVES: To review 26 consecutive patients with sustained monomorphic ventricular tachycardia (VT) of left ventricular origin, who underwent direct VT surgery. METHODS: Economic factors precluded the use of an implantable cardioverter defibrillator (ICD) in the majority of these patients, and the indication for surgery in 81% of patients was for failed medical drug therapy and 27% of patients had frequent or incessant life-threatening VT. The principles of direct VT surgery included intraoperative mapping, extended endocardial resection, cryoablation, left ventricular aneurysm repair by left ventricular remodelling and endoaneurysmorrhaphy, as well as coronary artery bypass grafting. RESULTS: Two patients with non-ischaemic VT were significantly younger (37.7 +/- 19.4 years, P = 0.03), had lower preoperative New York Heart Association class (P = 0.03), and had better left ventricular ejection fractions of 59.5 +/- 2.1% (P = 0.001) than the 24 ischaemic patients. No operative mortality or recurrence of VT occurred in this group. Ischaemic VT patients had an operative mortality of 8.3%; risk factors were concomitant valve surgery (P = 0.02), and perioperative intra-aortic balloon pump (P = 0.02). Surgery improved the left ventricular ejection fraction from 28.4 +/- 9.8% to 43.2 +/- 8.2% (P = 0.0001). Freedom from recurrence or inducibility of VT in operative survivors was 78.8 +/- 9.6% at 10 years; risk factors were arrhythmic focus remote to the left ventricular aneurysm (P = 0.015), and simple cryoablation or endocardial resection alone and not in combination (P = 0.003). Survival was 54.1 +/- 11.6% and 43.3 +/- 13.4% at 5 and 10 years, respectively, and there were no arrhythmic or sudden cardiac deaths. Patients with immediately life-threatening VT unsuitable for ICD implantation requiring urgent or emergent VT surgery had a 10-year survival of 22.2 +/- 13.9% compared to the more elective surgical group with a rate of 73.3 +/- 13.9% (P = 0.08). CONCLUSIONS: Direct VT surgery should remain an objective for symptomatic drug refractory VT of left ventricular origin.  相似文献   
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