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81.
Effect of an acrylic intraocular lens with a sharp posterior optic edge on posterior capsule opacification 总被引:3,自引:0,他引:3
Buehl W Findl O Menapace R Rainer G Sacu S Kiss B Petternel V Georgopoulos M 《Journal of cataract and refractive surgery》2002,28(7):1105-1111
PURPOSE: To compare the posterior capsule opacification (PCO) inhibiting effect of the sharp posterior optic edge design of the Sensar OptiEdge AR40e intraocular lens (IOL) (Allergan Surgical) with that of the round-edged design of the Sensar AR40 IOL.Setting Department of Ophthalmology, University of Vienna, Vienna, Austria.METHODS: This prospective randomized patient- and examiner-masked study comprised 106 eyes of 53 patients with bilateral age-related cataract. Each patient had cataract surgery in both eyes and received an AR40 IOL in 1 eye and an AR40e IOL in the other eye. Postoperative examinations were at 1 week, 2 and 6 months, and 1 year. Digital slitlamp and digital retroillumination images of each eye were taken. The amount of PCO was assessed subjectively at the slitlamp and objectively using automated image-analysis software.RESULTS: The AR40e group had significantly less regeneratory and fibrotic PCO 1 year after surgery. The mean automated image-analysis software PCO score (scale 0 to 10) was 2.19 in the AR40 group and 1.10 in the AR40e group (P <.001). The AR40e group had less peripheral fibrotic PCO. There was no significant difference in patient-reported edge glare between the 2 IOL groups.CONCLUSIONS: The sharp-edged design of the Sensar OptiEdge AR40e IOL led to significantly less PCO than the round-edged AR40 IOL 1 year postoperatively. 相似文献
82.
83.
The vacuum-assisted closure system for the treatment of deep sternal wound infections after cardiac surgery 总被引:3,自引:0,他引:3
Fleck TM Fleck M Moidl R Czerny M Koller R Giovanoli P Hiesmayer MJ Zimpfer D Wolner E Grabenwoger M 《The Annals of thoracic surgery》2002,74(5):1596-600; discussion 1600
BACKGROUND: The VAC system (vacuum-assisted wound closure) is a noninvasive active therapy to promote healing in difficult wounds that fail to respond to established treatment modalities. The system is based on the application of negative pressure by controlled suction to the wound surface. The method was introduced into clinical practice in 1996. Since then, numerous studies proved the effectiveness of the VAC System on microcirculation and the promotion of granulation tissue proliferation. METHODS: Eleven patients (5 men, 6 women) with a median age of 64.4 years (range 50 to 78 years) with sternal wound infection after cardiac surgery (coronary artery bypass grafting = 5, aortic valve replacement = 5, ascending aortic replacement = 1) were fitted with the VAC system by the time of initial surgical debridement. RESULTS: Complete healing was achieved in all patients. The VAC system was removed after a mean of 9.3 days (range 4 to 15 days), when systemic signs of infection resolved and quantitative cultures were negative. In 6 patients (54.5%), the VAC system was used as a bridge to reconstructive surgery with a pectoralis muscle flap, and in the remaining 5 patients (45.5%), primary wound closure could be achieved. Intensive care unit stay ranged from 1 to 4 days (median 1 day). Duration of hospital stay varied from 13 to 45 days (median 30 days). In-hospital mortality was 0%, and 30-day survival was 100%. CONCLUSIONS: The VAC system can be considered as an effective and safe adjunct to conventional and established treatment modalities for the therapy of sternal wound infections after cardiac surgery. 相似文献
84.
Measurement of brain tissue oxygenation performed using positron emission tomography scanning to validate a novel monitoring method 总被引:8,自引:0,他引:8
Gupta AK Hutchinson PJ Fryer T Al-Rawi PG Parry DA Minhas PS Kett-White R Kirkpatrick PJ Mathews JC Downey S Aigbirhio F Clark J Pickard JD Menon DK 《Journal of neurosurgery》2002,96(2):263-268
OBJECT: The benefits of measuring cerebral oxygenation in patients with brain injury are well accepted; however, jugular bulb oximetry, which is currently the most popular monitoring technique used has several shortcomings. The goal of this study was to validate the use of a new multiparameter sensor that measures brain tissue oxygenation and metabolism (Neurotrend) by comparing it with positron emission tomography (PET) scanning. METHODS: A Neurotrend sensor was inserted into the frontal region of the brain in 19 patients admitted to the neurointensive care unit. After a period of stabilization, the patients were transferred to the PET scanner suite where C15O, 15O2, and H2(15)O PET scans were obtained to facilitate calculation of regional cerebral blood volume, O2 metabolism, blood flow, and O2 extraction fraction (OEF). Patients were given hyperventilation therapy to decrease arterial CO2 by approximately 1 kPa (7.5 mm Hg) and the same sequence of PET scans was repeated. For each scanning sequence, end-capillary O2 tension (PvO2) was calculated from the OEF and compared with the reading of brain tissue O2 pressure (PbO2) provided by the sensor. In three patients the sensor was inserted into areas of contusion and these patients were eliminated from the analysis. In the subset of 16 patients in whom the sensor was placed in healthy brain, no correlation was found between the absolute values of PbO2 and PvO2 (r = 0.2, p = 0.29); however a significant correlation was obtained between the change in PbO2 (deltaPbO2) and the change in PvO2 (deltaPvO2) produced by hyperventilation in a 20-mm region of interest around the sensor (p = 0.78, p = 0.0035). CONCLUSIONS: The lack of correlation between the absolute values of PbO2 and PvO2 indicates that PbO2 cannot be used as a substitute for PvO2. Nevertheless, the positive correlation between deltaPbO2 and deltaPvO2 when the sensor had been inserted into healthy brain suggests that tissue PO2 monitoring may provide a useful tool to assess the effect of therapeutic interventions in brain injury. 相似文献
85.
Wareham NJ Jakes RW Rennie KL Mitchell J Hennings S Day NE 《International journal of epidemiology》2002,31(1):168-174
BACKGROUND: Physical activity is an important lifestyle which is often poorly assessed in epidemiological studies. The European Prospective Investigation into Cancer Study-Norfolk cohort (EPIC-Norfolk), a large population-based cohort study, has developed a comprehensive questionnaire to assess activity in different domains of life aimed at assessing total energy expenditure. We report the repeatability of this instrument and its validity against repeated objective measures of fitness and energy expenditure undertaken throughout the time frame of reference of the questionnaire. METHODS: The validity of the instrument was measured in 173 individuals randomly selected from a continuing population-based cohort study. Energy expenditure was assessed by four separate episodes of 4-day heart-rate monitoring, a method previously validated against whole body calorimetry and doubly-labelled water. Cardio-respiratory fitness was assessed by four repeated measures of sub-maximum oxygen uptake. At the end of the 12-month period, participants completed the physical activity questionnaire that assesses past-year activity at home, work and in recreation. Repeatability was assessed in a separate group of 399 randomly selected participants in EPIC who completed the physical activity questionnaire twice with a 3-month interval. RESULTS: The age- and sex-adjusted correlation between the objective measure of daytime energy expenditure and the sum of recreational and occupational reported physical activity (in MET h per week) was 0.28 (P < 0.001). The reported time spent in vigorous activity was correlated with cardio-respiratory fitness (0.16, P < 0.05) and with the proportion of time when energy expenditure was more than five times basal (0.17, P < 0.05). The repeatability of the sum of recreational and occupational reported activity was high, r = 0.73. CONCLUSIONS: The indices of physical activity derived from this questionnaire have levels of validity and repeatability comparable to other physical activity instruments that are used in large epidemiological studies and which have undergone such intense development and testing. 相似文献
86.
Dixelius J Cross M Matsumoto T Sasaki T Timpl R Claesson-Welsh L 《Cancer research》2002,62(7):1944-1947
Endostatin, an endogenous angiogenesis inhibitor, attenuates endothelial cell migration through an unknown mechanism. We show that endostatin induced tyrosine phosphorylation of focal adhesion kinase and paxillin, and promoted formation of focal adhesions and actin stress fibers, similar to fibroblast growth factor-2 (FGF-2). In cells cotreated with endostatin and FGF-2, focal adhesions and actin stress fibers were decreased, indicating that endostatin disturbs cell-matrix adhesion. Reduced tyrosine phosphorylation and cytoplasmic relocalization of beta-catenin in cells treated with FGF-2 and endostatin indicates that loosening of cell-cell adhesion is also disturbed by endostatin. These data provide a molecular basis both for the lack of effect of endostatin on the normal, quiescent vasculature, and its antagonistic effects on stimulated tumor vessels. 相似文献
87.
Local staging of pancreatic carcinoma with multi-detector row CT: use of curved planar reformations initial experience 总被引:24,自引:0,他引:24
Prokesch RW Chow LC Beaulieu CF Nino-Murcia M Mindelzun RE Bammer R Huang J Jeffrey RB 《Radiology》2002,225(3):759-765
PURPOSE: To evaluate the utility of curved planar reformations compared with standard transverse images in the assessment of pancreatic tumors. MATERIALS AND METHODS: Forty-three patients suspected of having pancreatic tumors underwent contrast material-enhanced biphasic multi-detector row computed tomography (CT). Curved planar reformations were generated along the pancreatic duct, common bile duct, and major mesenteric vessels. Three blinded independent readers assessed the curved planar reformations and transverse images separately for the presence of tumor, resectability, and vascular involvement. The results were compared with those of a consensus panel who evaluated the curved planar reformations and transverse images together along with clinical data and surgical findings. RESULTS: Of 43 patients, 20 had pancreatic malignancies as judged by the consensus panel and proven at biopsy and/or clinical follow-up. For tumor detection, transverse images and curved planar reformations had an average sensitivity of 95.0% and 98.4% (P >.05), respectively, and an average specificity of 90.9% and 91.3% (P >.05), respectively. For tumor resectability, transverse images and curved planar reformations had an average sensitivity of 85.7% and 71.4% (P >.05), respectively, and an average specificity of 85.2% and 84.3% (P >.05), respectively. Average interpretation time was 6.4 minutes with transverse images and 4.1 minutes with curved planar reformations. CONCLUSION: Curved planar reformations are equivalent to transverse images in the detection of pancreatic tumors and determination of surgical resectability. 相似文献
88.
Rupert Bartsch Sabine Fromm Margaretha Rudas Catharina Wenzel Stefanie Harbauer Karl Roessler Klaus Kitz Guenther G. Steger Hajo-Dirk Weitmann Richard Poetter Christoph C. Zielinski Karin Dieckmann 《Radiotherapy and oncology》2006,80(3):313-317
BACKGROUND: Brain metastases have evolved from a rare to a frequently encountered event in advanced breast cancer due to advances in palliative systemic treatment. PATIENTS AND METHODS: All Patients treated at our centre from 1994 to 2004 with WBRT for brain metastases from breast cancer were included. We performed a multivariate analysis (Cox regression) to explore which factors are able to influence significantly cerebral time to progression (TTP) and overall survival (metastatic sites [visceral versus non-visceral], Karnofsky performance score [KPS], age, intensified local treatment [boost irradiation, neuro-surgical resection] further systemic treatment). RESULTS: Overall 174 patients, median age 51 years, range 27-76 years, were included. Median TTP was 3 months (m), range 1-33+ m. Median overall survival was 7 m, range 1-44 m. Factors significantly influencing TTP were KPS (p = 0.002), intensified local treatment (p < 0.001), and palliative systemic treatment (p = 0.001). Factors significantly influencing survival were intensified local treatment (p = 0.004), metastatic sites (p = 0.008), KPS (p = 0.006), and palliative systemic treatment (p < 0.001). CONCLUSION: As shown by the significant influence of metastatic sites, some patients die from their advanced systemic tumour situation before they would die from cerebral progression. In other individuals however, intensified local treatment and systemic treatment appear to influence cerebral time to progression and overall survival. 相似文献
89.
Neil James Sebire Alan Ramsay Mary Sheppard Marian Malone Brian Harding Rupert Anthony Risdon 《Pediatric and developmental pathology》2002,5(4):400-404
Inflammatory myofibroblastic tumor (IMT), previously described as inflammatory pseudotumor, can occur at any age but is a
recognized soft tissue tumor of childhood. Less than 10 previous cases have been described of IMT affecting the heart, in
patients ranging from 5 months to 17 years of age. We present three unusual, but similar, cases of IMT in infants, which were
all predominantly intravascular in location, one of which was associated with death due to angiodestructive lesions of the
coronary and cerebral arteries. These cases demonstrate an apparently distinct phenotype, with a predominant intravascular
location of the tumor. Furthermore, this series highlights the difficulty in categorizing such lesions as benign versus malignant
on histological grounds alone. IMT should be considered in the differential diagnosis of unusual pediatric intravascular spindle
cell lesions. 相似文献
90.
Rupert W Jakes Stephen W Duffy Fook-Cheong Ng Fei Gao Eng-Hen Ng Adeline Seow Hin-Peng Lee Mimi C Yu 《Cancer epidemiology, biomarkers & prevention》2002,11(7):608-613
The study aimed to investigate whether self-reported dietary variables were associated with mammographic parenchymal patterns, which have been shown to predict risk of breast cancer. Among the 3,421 women, ages 45-74 years, common to two independent population-based cohorts, mammographic parenchymal patterns and current dietary habits were assessed for 406 randomly chosen participants. Logistic regression methods were used to compare dietary and other lifestyle profiles between subjects classified as displaying high (cases) and low risk (controls) parenchymal patterns. After adjustment for energy intake and other potential confounders, dietary soy protein intake was inversely related to risk of high-risk parenchymal pattern (odds ratio, 0.41; 95% confidence interval, 0.18-0.94, highest versus lowest quartile of intake). Similarly, the highest versus lowest quartile of dietary soy isoflavone intake was significantly related to low-risk parenchymal patterns (odds ratio, 0.44; 95% confidence interval, 0.20-0.98). The association between high soy intake and a reduced risk of mammographic parenchymal patterns that are associated with high breast cancer risk may have important implications in breast cancer prevention. 相似文献