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排序方式: 共有1821条查询结果,搜索用时 15 毫秒
91.
Sam CK Cheng BScOptom Maurice KH Yap PhD MCOptom FAAO Ernest Goldschmidt MD DrSci Peter G Swann BSc MAppSc FCOptom FAAO honFIES Larry HY Ng PDOptom OD FAAO FBCLA Carly SY Lam PhD MSc MCOptom FAAO 《Clinical & experimental optometry》2008,91(4):373-378
Background: Optomap uses the ultra‐wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non‐mydriatic conditions. Methods: Fifty‐four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo‐documentation of fundal changes was obtained with the Optomap under non‐mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD‐9‐CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white‐without‐pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography. 相似文献
92.
Nicholas Tachino Rick Hayashi Christina Liew George Bailey Roderick Dashwood 《Molecular carcinogenesis》1995,12(4):187-192
Aberrant crypt foci (ACF) are putative peneoplastic lesions that develop after treatment of animals with colon carcinogens, including cooked-meat heterocyclic amines such as 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). Male F344 rats given IQ by gavage on alternating days for 2 wk (130 mg/kg body weight) and killed 12 wk after the final carcinogen dose had an average of 4.4 ACF/colon and an average of 3.2 crypts/focus. The DNA from these ACF was amplified by the polymerase chain reaction and analyzed by 3′-primer mismatch and direct sequencing methods for mutations in the Ki-ras proto-oncogene. Of the 37 IQ-induced ACF screened, three contained a GGT→GAT mutation in codon 12 and one contained a GGC→GCC mutation in codon 13. The approximately 11% frequency of mutation in IQ-induced ACF is within the range of previous ACF studies of azoxymethane, which reported a 7–37% incidence of Ki-ras mutaion. These findings suggest that for both compounds, ras mutations occur during early stages of colorectal tumorigenesis. However, while ras mutations can be detected with increasing frequency in azoxymethane-induced adenomas and carcinomas, they are reportedly absent in IQ-induced colon tumors. Thus, for IQ and related compounds additional factors (possibly increased cell proliferation) may be important in the later stages of colorectal tumorigenesis. © 1995 Wiley-Liss Inc. 相似文献
93.
A 45-year-old man with primary systemic amyloidosis was found to have bilateral uveal effusions secondary to thickened sclera according to magnetic resonance imaging of the orbits. The patient was treated with bilateral sclerectomies and vortex vein decompression, and had an excellent outcome. Light microscopy of excised sclera revealed severe infiltration of the tissue by amyloid. To our knowledge, this is the first report of amyloid infiltration of the sclera leading to uveal effusion. Arch Ophthalmol. 2000;118:1293-1295 相似文献
94.
Abstract
In recent times, there have been many developments in therapies for acute heart failure, in contrast to the preceding 20 years. These have been mainly fuelled by new and expanding knowledge about the pathophysiology of heart failure, which has allowed for insight into potential therapeutic strategies. This review will examine the key emerging therapies for acute heart failure, in light of available pathophysiological and clinical evidence. (Intern Med J 2003; 33: 515−520) 相似文献
In recent times, there have been many developments in therapies for acute heart failure, in contrast to the preceding 20 years. These have been mainly fuelled by new and expanding knowledge about the pathophysiology of heart failure, which has allowed for insight into potential therapeutic strategies. This review will examine the key emerging therapies for acute heart failure, in light of available pathophysiological and clinical evidence. (Intern Med J 2003; 33: 515−520) 相似文献
95.
96.
In contrast to curative therapies, preventive therapies are administered to largely healthy individuals over long periods. The risk-benefit and cost-benefit ratios are more likely to be unfavourable, making treatment decisions difficult. Drug trials provide insufficient information for treatment decisions, as they are conducted on highly selected populations over short durations, estimate only relative benefits of treatment and offer little information on risks and costs. Epidemiological modelling is a method of combining evidence from observational epidemiology and clinical trials to assist in clinical and health policy decision-making. It can estimate absolute benefits, risks and costs of long-term preventive strategies, and thus allow their precise targeting to individuals for whom they are safest and most cost-effective. Epidemiological modelling also allows explicit information about risks and benefits of therapy to be presented to patients, facilitating informed decision-making. 相似文献
97.
中国流行性乙型脑炎防制策略 总被引:7,自引:0,他引:7
流行性乙型脑炎(简称乙脑)是由携带乙脑病毒的蚊子叮咬人体引起的急性中枢神经系统传染病,是一种人畜共患的自然疫源性疾病.临床以高热、嗜睡、惊厥、昏迷、抽搐为主要表现,严重者可致死亡,部分病例可留有后遗症.近年来,我国每年的乙脑病例数波动于5000例~8000例之间,在法定传染病排序中位于前10位以外,其死亡数和病死率分别排在第2位~6位和第4位~8位,在我国局部地区时有暴发,依旧是严重威胁儿童健康的主要传染病之一.本文在对我国乙脑防治工作现况、存在的问题进行分析的基础上,提出了相应的防制策略.…… 相似文献
98.
99.
The aim of this prospective study was to measure quality of life in patients with chronic leg ulcers. All eligible, consenting patients who attended the leg ulcer clinic at the Repatriation General Hospital (Tasmania, Australia) during the 16-month study period were included. Patients completed questionnaires on their first visit and at follow-up which occurred, on average, eight weeks later. This study found an improvement in three quality-of-life indicators--pain, sleep and mobility--over an average of eight weeks' treatment involving one to three visits to the clinic and home visits by primary care nurses. Of the 57 patients, 53 (93%) indicated that their wound had improved following attendance at the clinic. The cost-effectiveness of providing treatment in a dedicated leg ulcer clinic has been the focus of many previous studies. This study emphasises the additional benefits a dedicated clinic may have in improving quality of life in patients with chronic leg ulcers. Such benefits ought to be considered when allocating resources to leg ulcer services. 相似文献
100.
Non-histone chromatin proteins (NHCP) were isolated from skeletal muscle, left ventricle and liver of swine susceptible to malignant hyperthermia and from controls. These proteins were extracted with phenol buffers and fractionated by polyacrylamide gel electrophoresis. Isoelectrofocusing gel electrophoresis revealed quantitative differences in NHCP from skeletal muscle between disease and control groups. The high resolution of proteins by two-dimensional polyacrylamide gel electrophoresis showed a relative similarity between skeletal muscle, heart and liver although some differences could be discerned. Non-histone chromatin proteins of molecular weight 35,000–45,000, focusing between pH 7 and 9, were increased in skeletal muscle nuclei derived from malignant hyperthermia-susceptible swine. These proteins appear to be important in the maturation of messenger RNA. No alterations were seen in either heart or liver. We conclude that an increase in NHCP which is associated with the processing of messenger RNA, may be important in the phenotypic expression in skeletal muscle of malignant hyperthermia in swine. 相似文献