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81.
PurposeTo refine estimates of macular soft drusen abundance in eyes with age-related macular degeneration (AMD) and evaluate hypotheses about drusen biogenesis, we investigated topographic distribution and growth rates of drusen by optical coherence tomography (OCT). We compared results to retinal features with similar topographies (cone density and macular pigment) in healthy eyes.MethodsIn a prospective study, distribution and growth rates of soft drusen in eyes with AMD were identified by human observers in OCT volumes and analyzed with computer-assistance. Published histologic data for macular cone densities (n = 12 eyes) and in vivo macular pigment optical density (MPOD) measurements in older adults with unremarkable maculae (n = 31; 62 paired eyes, averaged) were revisited. All values were normalized to Early Treatment Diabetic Retinopathy Study (ETDRS) subfield areas.ResultsSixty-two eyes of 44 patients were imaged for periods up to 78 months. Soft drusen volume per unit volume at baseline is 24.6-fold and 2.3-fold higher in the central ETDRS subfield than in outer and inner rings, respectively, and grows most prominently there. Corresponding ratios (central versus inner and central versus outer) for cone density in donor eyes is 13.3-fold and 5.1-fold and for MPOD, 24.6 and 23.9-fold, and 3.6 and 3.6-fold.ConclusionsNormalized soft drusen volume in AMD eyes as assessed by OCT is ≥ 20-fold higher in central ETDRS subfields than in outer rings, paralleling MPOD distribution in healthy eyes. Data on drusen volume support this metric for AMD risk assessment and clinical trial outcome measure. Alignment of different data modalities support the ETDRS grid for standardizing retinal topography in mechanistic studies of drusen biogenesis.  相似文献   
82.
Background : Although current clinical guidelines recommend the use of thrombus aspiration (TA) during primary percutaneous coronary intervention (PPCI), previous studies evaluating TA demonstrated contradictory results. The aim of this study was to evaluate long‐term clinical outcome after TA in adjunct to PPCI for acute ST‐segment myocardial infarction (STEMI), as compared with conventional treatment, with the use of paclitaxel‐eluting stents or bare‐metal stents. Methods : We analyzed data of the PASSION trial, in which 619 patients with STEMI were randomly assigned to a paclitaxel‐eluting stent or a bare‐metal stent. TA was performed in 311 patients (50.2%). Clinical endpoints at 2 years were compared between patients who received TA during PPCI with patients who underwent conventional PPCI. The primary outcome of interest was a composite of cardiac death, recurrent myocardial infarction (MI), or target‐lesion revascularization (TLR). A propensity score model was made to account for baseline differences that could have affected the probability of performing TA. Results : Complete follow‐up was available for 598 patients (96.6%). The cumulative incidence of the combined outcome measure of cardiac death, recurrent MI, or TLR was 40 (13.0%) in the TA group and 41 (13.5%) in the conventional PPCI group (HR 0.96; 95% CI 0.62–1.47; P = 0.84). Also after adjusting for propensity score, no significant difference in event rate was observed between both treatment groups. Conclusions : In this post‐hoc analysis of the PASSION trial, TA in adjunct to PPCI did not affect rates of major adverse cardiac events at 2 years follow‐up, as compared with conventional PPCI. © 2011 Wiley Periodicals, Inc.  相似文献   
83.
Whole-brain dynamic time-resolved computed tomography angiography (CTA) is a technique developed on the new 320-detector row CT scanner capable of generating time-resolved cerebral angiograms from skull base to vertex. Unlike a conventional cerebral angiogram, this technique visualizes pial arterial filling in all vascular territories, thereby providing additional hemodynamic information. Ours was a retrospective study of consecutive patients with ischemic stroke and M1 middle cerebral artery +/−intracranial internal carotid artery occlusions presenting to our center from June 2010 and undergoing dynamic time-resolved CTA and perfusion CT within 6 hours of symptom onset. Leptomeningeal collateral status was assessed by determining relative prominence of pial arteries in the ischemic region, rate and extent of retrograde flow, and various topographical patterns of pial arterial filling. Twenty-five patients were included in the study. We demonstrate the existence of the following novel properties of leptomeningeal collaterals in humans: (a) posterior (posterior cerebral artery (PCA)–MCA) dominant collateralization, (b) intra-territorial ‘within MCA region'' leptomeningeal collaterals, and (c) significant variability in size, extent, and retrograde filling time in pial arteries. We also describe a simple and reliable collateral grading template that, for the first time on dynamic CTA, incorporates back-filling time as well as size and extent of collateral filling.  相似文献   
84.
85.

Purpose

To determine whether the immunohistochemical markers survivin and E-cadherin can predict progress at initially diagnosed Ta bladder cancer.

Methods

We retrospectively searched for every initially diagnosed pTa urothelial bladder carcinoma having been treated at our single-center hospital in Germany from January 1992 up to December 2004. Follow-up was recorded up to June 2010, with recurrence or progress being the endpoints. Immunohistochemical staining and analysis of survivin and E-cadherin of the TURB specimens were performed. Outcome dependency of progression and no progression with immunohistochemical staining was analyzed using uni- and multivariate regression analysis, Kaplan–Meier analysis and uni- and multivariate Cox regression analysis.

Results

Overall, 233 patients were included. Forty-two percent of those were tumor free in their follow-up TURBs, 46 % had at least one pTa recurrence and 12 % even showed progress to at least pT1 bladder cancer. Aberrant staining of E-cadherin was found within 71 % of patients with progression in contrast to only 40 % in cases without progression (p = 0.004). Of all progressed patients, 92 % showed overexpression of survivin in their initial pTa specimen compared to 61 % without progression (p = 0.001). Kaplan–Meier analysis revealed aberrant E-cadherin staining to be associated with worse progression-free survival (PFS) (p = 0.005) as well as overexpression of survivin (p = 0.003). In multivariate Cox regression analysis, strong E-cadherin staining was an independent prognosticator for better PFS (p = 0.033) and multifocality (p = 0.046) and tumor size over 3 cm (p = 0.042) were prognosticators for worse PFS.

Conclusion

Adding the immunohistochemical markers survivin and E-cadherin could help to identify patients at risk of developing a progressive disease in initial stage pTa bladder cancer.
  相似文献   
86.
BACKGROUND AND AIMS: Chronic lymphocytic leukaemia (CLL) is a frequent non-Hodgkin lymphoma characterised by a heterogeneous clinical course. Assessment of cell cycle phase kinetics might be important for prediction of clinical behaviour and prognosis. METHODS: Distribution of neoplastic cells in CLL within the cell cycle was evaluated by determining the labelling indices (LI, i.e. percentage of positive cells) of markers specific for late G1-phase (cyclin E), S-phase (cyclin A), and G2/M-phase (cyclin B1), and Mcm2, a novel marker of proliferative potential, in a large cohort of patients (n = 79) using tissue microarray (TMA) technology. Utilising a combination of these markers, an algorithm was developed--subtracting the combined LIs of cyclin E, cyclin A and cyclin B1 from the LI of Mcm2--to determine the percentage of tumour cells residing in early G1-phase, which is probably a critical state for the malignant potential of CLL. RESULTS: 27.11% of cells had acquired proliferative potential as indicated by expression of Mcm2. Only a small number of cells were found to be in late G1-phase (7.16%), S-phase (3.31%) or G2/M-phase (0.98%), while 15.66% of cells were considered to be in early G1-phase. CONCLUSION: Cell cycle phase distribution can easily be assessed by immunohistochemistry in routinely processed paraffin-embedded specimens. A large number of neoplastic cells in CLL have proliferative potential, with a significant sub-population residing in early G1-phase. Estimates of these cells may identify cases likely to exhibit a more aggressive biological behaviour and adverse clinical course.  相似文献   
87.

Background

Literature abounds linking one’s job to certain unpalatable health outcomes. Since exposures to hazardous conditions in industrial environments often results in sundry health effects among workers, we embarked on this study to investigate the hepatic health effects of occupational activities in the petroleum refining and distribution industry.

Method

Biochemical markers of liver functions were assayed in plasma, using Reflotron dry chemistry spectrophotometric system. The study was conducted on randomly selected workers of Port Harcourt Refining Company (PHRC) and Pipelines and Petroleum Product Marketing Company (PPMC) both in Alesa-Eleme near Port Harcourt, Nigeria, as well as non-oil work civil servants serving as control subjects.

Result and conclusion

Results showed that, bilirubin ranged 0.3-1.6 mg/dl with a mean of 0.66±0.20mg/dl among the oil workers as against 0.5-1.00mg/dl with a mean of 0.58±0.13mg/dl in non-oil workers, Alkaline phosphatase ranged 50.00-296.00u/l (mean: 126.21±39.49u/l) in oil workers as against 40.20-111u/l (mean: 66.83±18.54u/l) for non-oil workers, Aspartic transaminases (AST) ranged 5.80-140.20u/l (mean: 21.81±11.49u/l) in oil workers against 18.00-44.00u/l (mean: 26.89±6.99u/l) for non-oil workers, while Alanine transaminases (ALT) ranged 4.90-86.00u/l (mean: 22.14±11.28u/l) in oil workers as against 10.00-86.60u/l (mean: 22.30±10.22u/l) for the non-oil workers. A close study of the results revealed that although the mean values for all the studied parameters were still within the parametric reference ranges, however, relative to the referents, there were significant increases (P<0.05) in plasma bilirubin (though anicteric) and alkaline phosphatase that was not matched with a corresponding increase in the plasma transaminases, suggesting a possibility that toxic anicteric hepatoxicity is part of the potential health effects of sundry exposures in the Nigeria petroleum oil refining and distribution industry. Gender differentiation data showed that though the mean values for the parameters were higher in males than females, the increases were not significant in most cases (P>0.05), whereas data for age and exposure period classifications revealed that irrespective of the age of the worker, the effects are likely to start after the first five years, manifesting fully after the first decade of occupational exposures. Thus, an update of industrial/occupational health measures is necessary for a safer and healthier work environment.  相似文献   
88.
Visacane is a sugarcane quarantine station located in the South of France, far away from sugarcane growing areas. Visacane imports up to 100 sugarcane varieties per year, using safe control and confinement measures of plants and their wastes to prevent any risk of pathogen spread outside of the facilities. Viruses hosted by the imported material are either known or unknown to cause disease in cultivated sugarcane. Poaceae viruses occurring in plants surrounding the quarantine glasshouse are currently unknown. These viruses could be considered as a source of new sugarcane infections and potentially cause new sugarcane diseases in cases of confinement barrier failure. The aim of this study was to compare the plant virome inside and outside of the quarantine station to identify potential confinement failures and risks of cross infections. Leaves from quarantined sugarcane varieties and from wild Poaceae growing near the quarantine were collected and processed by a metagenomics approach based on virion-associated nucleic acids extraction and library preparation for Illumina sequencing. While viruses belonging to the same virus genus or family were identified in the sugarcane quarantine and its surroundings, no virus species was detected in both environments. Based on the data obtained in this study, no virus movement between quarantined sugarcane and nearby grassland has occurred so far, and the confinement procedures of Visacane appear to be properly implemented.  相似文献   
89.
Abdominal Radiology - To develop and validate a scoring system using a combination of imaging and clinical parameters to predict 30-day mortality in ruptured HCC (rHCC) patients after transarterial...  相似文献   
90.
To study the efficacy of a treatment strategy for the management of hypertensive urgencies, the authors evaluated 549 patients admitted to the emergency department. They were first assigned to a 30-minute rest period, then a follow-up blood pressure measurement was carried out. Patients who did not respond to rest were randomly assigned to receive an oral dose of an antihypertensive drug with different mechanisms of action and pharmacodynamic properties (perindopril, amlodipine, or labetalol), and blood pressure was reassessed at 60- and 120-minute intervals. A satisfactory blood pressure response to rest (defined as postintervention systolic blood pressure < 180 mm Hg and diastolic blood pressure < 110 mm Hg, with at least a 20 mm Hg reduction in basal systolic blood pressure and/or a 10-mm Hg reduction in basal diastolic blood pressure) was observed in 31.9% of population. Among nonresponders, 79.1% had a satisfactory blood pressure response to the antihypertensive drug treatment in a 2-hour average follow-up period. No major adverse events were observed. This treatment strategy, based on standardized rest as an initial step and different antihypertensive drugs, can be effective and safe for the management of patients with hypertensive urgencies.  相似文献   
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