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Despite the current popularity of binocular indirect ophthalmoscopy, direct ophthalmoscopes are still commonly used by clinicians for fundus examination. They are considered to be expensive, however, and it has been suggested that this cost can prevent their use by healthcare professionals in developing countries. The Optyse Lens Free Ophthalmoscope is a novel direct ophthalmoscope, without a lens focus system, that allows for comparatively inexpensive manufacture and supply. We compared the clarity of view with the Optyse to that with standard direct ophthalmoscopes, over a sequential cohort of patients with a variety of refractive errors and ocular conditions. The grade of clarity of view with the Optyse Lens Free Ophthalmoscope was less than conventional ophthalmoscopes (Wilcoxon signed rank test, p < 0.0001). This grade of clarity of view was not associated with the ametropia of the ophthalmoscopic observation (Spearman r < or = 0.03, p > or = 0.28) but was with the presence of cataracts (chi2 test, p < 0.0001) with both the Optyse and the conventional ophthalmoscopes. Despite its limitations, the retinal view with Optyse was often within acceptable clinical limits suggesting that this relatively inexpensive ophthalmoscope may have a place when cost prohibits any other type of ophthalmoscope use.  相似文献   
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Fifteen partial parotid salivary gland resection specimens interpreted as benign lymphoepithelial lesion (BLL) were accessioned by our surgical pathology service between January 1983 and December 1986. Twelve of the specimens were removed from 11 prison inmates referred to our hospital, a patient subgroup constituting the source of only 2% of surgical pathology specimens in general. All prison inmates with BLL had a history of intravenous drug use, had developed unexplained lymphadenopathy concurrently with the parotid gland enlargement, and had suspected human immunodeficiency virus (HIV) infection (serologically confirmed in two). Histopathologic features of the parotid gland specimens included atypical follicular hyperplasia and follicular involution, resembling lymph node changes of HIV infection. The clinical and pathologic findings in these cases suggest an association between HIV infection and BLL, and support a previously proposed mechanism for the development of BLL through progressive enlargement of intraparotid lymph nodes.  相似文献   
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PURPOSE: The objectives of this study were to evaluate the effect of a cyclooxygenase (COX)-2 inhibitor, nimesulide, on the growth inhibition of s.c. human lung A549 adenocarcinoma tumors and to assess the effect of nimesulide on the expression of COX-2 and peroxisome proliferator-activated receptor (PPAR)-gamma in lung tumors harvested from mice. EXPERIMENTAL DESIGN: Female nu/nu mice were xenografted with s.c. A549 lung tumors, and 1 day after tumor implantation, the mice were fed with a diet containing nimesulide at 250-1500 ppm doses. Tumor dimensions were monitored twice weekly, and tumor samples isolated from mice were used to determine prostaglandin E(2) (PGE(2)) levels by enzyme immunoassay, expression of COX-2 and PPAR-gamma by Western blotting and immunohistochemistry. Furthermore, the induction of apoptosis in tumor specimens was determined by terminal deoxynucleotidyl transferase-mediated nick end labeling staining. RESULTS: Nimesulide treatment showed a dose-dependent growth-inhibitory effect of A549 tumors with a maximum of 77.7% inhibition at 1500 ppm of nimesulide. Western blotting experiments showed similar expression of COX-2 in both control and nimesulide (250-1500 ppm)-treated mice tumor tissues. PPAR-gamma was found to be overexpressed as a result of 1500 ppm nimesulide treatment and was not detected in tumors from control or 250-1000 ppm nimesulide-treated mice. Nimesulide (1500 ppm) significantly reduced intratumor PGE(2) levels (P < 0.001) and induced apoptosis in 25% of tumor cells as compared with control tumors. CONCLUSIONS: Nimesulide (1500 ppm) induced growth inhibition of A549 lung tumors is associated with the reduction of intratumor PGE(2) levels but without affecting the expression of COX-2. Nimesulide-induced enhancement of the expression of PPAR-gamma may also contribute to its antitumor effect, which needs to be further investigated.  相似文献   
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Background and PurposePrior studies examining sex-related risk of readmission for ischemic stroke (IS) after coronary artery bypass grafting (CABG) did not adjust for preoperative comorbidities and used small study samples that were single-center or otherwise poorly generalizable. We assessed risk of readmission for IS after CABG for females compared to males in a nationwide sample.MethodsThe 2013 Nationwide Readmissions Database contains data on 49% of all U.S. hospitalizations. We used population weighting to determine national estimates. Using all follow-up data up to 1 year after discharge from CABG hospitalization, we estimated Kaplan-Meier cumulative risk of IS, stratified by sex, using the log-rank test for significance. We created Cox proportional hazard models to calculate hazard ratios (HR) and 95% confidence intervals (CI) for IS readmission, with sex as the main independent variable. We ran unadjusted models and models adjusted for age, vascular risk factors, estimated severity of illness and risk of mortality, hospital characteristics, and income quartile of patient's zip code.ResultsAn estimated 53,270 females and 147,396 males survived index CABG admission in 2013. There was a consistently elevated cumulative risk of readmission for IS after CABG for females versus males (log-rank p-value = 0.0014). In the unadjusted Cox model, the HR of IS in females vs. males was 1.35 (95% CI 1.12–1.62, p = 0.0015). The elevated risk for females remained after adjusting for severity of illness (1.30 [1.08–1.56], p = 0.0056) and risk of mortality (1.28 [1.07–1.54], p = 0.0086). This elevated risk persisted after adjusting for multiple vascular risk factors, hospital characteristics, and income quartile of patient's zip code (1.23 [1.02–1.48], p = 0.03).ConclusionsWe found a 23% increased risk of readmission for IS up to 1 year after CABG for females compared to males in a fully adjusted model utilizing a large, contemporary, nationwide database. Further research would clarify mechanisms of this increased risk among women.  相似文献   
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OBJECTIVE: The aim of this study was to examine the effect of percutaneous oestradiol on the lipid profile and on atheroma formation using an animal model. METHODS: The study was of 12 weeks duration. Fifty sexually mature female New Zealand White rabbits were divided into five groups of equal size. Two groups acted as controls and received normal rabbit chow. Rabbits in one of these groups were ovariectomized. The remaining three groups were ovariectomized but received 1% cholesterol enriched rabbit chow. One of these cholesterol-fed groups received 0.3 mg/kg percutaneous oestradiol daily whilst another received 0.1 mg/kg oral oestradiol daily. Measurements of concentrations of total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and triglycerides (TG) were made at the beginning and end of the study. Aortic atheroma formation was measured using computerized image analysis of uptake of Sudan III staining. RESULTS: After 12 weeks there were significant increases in the mean concentrations of TC in the three cholesterol-fed groups compared with controls (P < 0.001). Changes in HDL-C and TG concentrations were less consistent. The mean area of aortic atheroma formation was significantly less in both the percutaneous oestradiol group (4.9%) and the oral oestradiol group (8.6%) compared with the non-oestrogen-treated cholesterol-fed group (19.5%) (P < 0.001, < 0.01 respectively). CONCLUSION: These results suggest that percutaneous oestradiol has a direct protective effect on atheroma formation independent of serum concentrations of total cholesterol.  相似文献   
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Patel  Urvish  Malik  Preeti  Shah  Dhaivat  Patel  Achint  Dhamoon  Mandip  Jani  Vishal 《Journal of neurology》2021,268(1):240-247
Journal of Neurology - Due to pro-inflammatory and hypercoagulation states, COVID-19 infection is believed to increase the risk of stroke and worsen the outcomes of the patients having pre-existing...  相似文献   
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BackgroundThis systematic review was undertaken to define and summarize existing, proposed quality performance indicators (QPI) for hepato-pancreatico-biliary (HPB) procedures.MethodsA systematic literature review identified studies reporting on quality indicators for cholecystectomy, hepatectomy, pancreatectomy and complex biliary surgical procedures. The databases searched were MEDLINE, EMBASE, PubMed, and SCOPUS, with all literature available until the search date of 1 May 2020 included. The reference lists of all included papers, as well as related review articles, were manually searched to identify further relevant studies.ResultsForty-five publications report quality indicators for pancreatectomy (n = 22), hepatectomy (n = 7), HPB resections in general (n = 12), and cholecystectomy (n = 6). No publications proposed QPI for complex biliary surgery. The 45 papers used national audit (n = 18), consensus methodology (n = 5), state-wide audit (n = 3), unit audit (n = 9), review methodology (n = 9), and survey methodology (n = 1). Sixty-one QPI were reported for pancreatectomy, 22 reported for hepatectomy, and 14 reported for HPB resections in general, in domains of infrastructure, provider, and documentation. Fourteen infrastructure and provider-based QPI were reported for cholecystectomy.ConclusionsThere are few internationally agreed QPI for HPB procedures that allow global comparison of provider performance and that set aspirational goals for patient care and experience.  相似文献   
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