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961.
PURPOSE: To examine vascular associations with pseudoexfoliation syndrome in view of the wide-spread elastosis now demonstrated in this disorder that affects many tissues, including vessel walls. METHODS: The Blue Mountains Eye Study is a population-based study of eye disease in an area west of Sydney, Australia. Of 4433 eligible persons aged 49 years or older, 3,654 (82.4%) participated. Signs of pseudoexfoliation were graded clinically, after excluding 108 people who had bilateral cataract surgery. RESULTS: Pseudoexfoliation was present in 81 (2.3%) of 3546 participants aged 49 years or older. The prevalence of pseudoexfoliation increased with age and was higher in women and in people with glaucoma. Pseudoexfoliation was statistically significantly associated with a history of angina or hypertension or a combined history of angina, acute myocardial infarction, or stroke. CONCLUSION: Slit-lamp signs of pseudoexfoliation may identify individuals with an increased vascular risk.  相似文献   
962.
BACKGROUND: Locally advanced thyroid cancer invading the tracheal cartilage represents a difficult treatment dilemma during thyroidectomy. METHODS: A retrospective chart review was performed to determine the results of laryngotracheal resection or tracheal cartilage shave with adjuvant radiotherapy in patients with locally advanced thyroid cancer invading the upper airway. RESULTS: Of 597 patients undergoing thyroidectomy for thyroid cancer, 40 were found to have laryngotracheal invasion. Thirty-five patients with superficial invasion underwent cartilage shave procedures with adjuvant radiotherapy; five with full-thickness invasion underwent radical resection, including tracheal sleeve resection (n = 3) or total laryngectomy (n = 2). Histologic subtypes included papillary (n = 32), follicular (n = 2), Hurthle cell (n = 1), medullary (n = 3), and anaplastic (n = 2). Of the cartilage shave group, 25 are currently alive with no evidence of disease at a mean follow-up of 81 months (range 1-290). Six developed isolated local/regional recurrence and were managed with total laryngectomy (n = 1), tracheal resection (n = 1), cervical lymphadenectomy (n = 1), or repeat radiotherapy (n = 3). All six patients remain free of disease at a mean follow-up of 5 years. Of those who underwent initial laryngotracheal resection, four remain free of disease at a mean follow-up of 5 years. The rates of 10-year disease-free survival and overall survival for all patients were 47.9% (95% confidence interval [CI] 24.8, 71.0) and 83.9% (95% CI 70.3, 97.5), respectively. CONCLUSIONS: These data suggest that adequate management of thyroid cancer with laryngotracheal invasion can be achieved with a more conservative surgical approach and adjuvant radiotherapy, reserving more radical resections for extensive primary lesions or locally recurrent disease.  相似文献   
963.
964.
采用恒位移试验方法,在高温、高压、氢环境中用WOL试样测试了214Cr-1Mo钢及其焊接接头的应力腐蚀门限应力强度因子KIH。试验结果表明:采用恒位移试验方法测试高温、高压、氢环境中214Cr-1Mo钢及其焊接接头的KIH是可行的。  相似文献   
965.
A 2 cm long three-contact multisection laser has been fabricated for modelocking at very low repetition rates. Active modelocking yields 8.0-12.3 ps pulses at 2.2, 4.3 and 6.5 GHz corresponding to the fundamental, first, and second harmonics of the cavity resonance frequency. This device demonstrates the feasibility of fabricating monolithic pulse sources operating at rates as low as the OC-48 Sonet transmission rate (2.488 Gbit/s).<>  相似文献   
966.
967.
The dissolution of titanium in simulated interstitial electrolyte (SIE), human serum in SIE (serum/SIE) and 8.0 mM ethylenediaminetetraacetic acid (EDTA) in SIE (EDTA/SIE) was measured in vitro. Titanium fibre samples were immersed in these solutions and maintained at 37°C, 10% O2, 5% CO2 and 97±3% relative humidity for 0–5000 h. The concentration of titanium released was quantified using electrothermal atomic absorption spectroscopy. Changes in oxide stoichiometry were determined by Auger electron spectroscopy after processing and immersion in the test solutions. The oxide became nearly stoichiometric TiO2 after immersion, suggesting equilibration of the surface with the solutions. Solution ligands enhanced the magnitude of dissolution, with EDTA>serum/SIE>SIE. The dissolution kinetics were empirically fitted by a two-phase logarithmic relationship. The first phase of dissolution (t<300 h) was dominated by equilibration of the oxide with the solution and the second phase (t>300 h) by mass diffusion. The dissolution kinetics were similar for the EDTA/SIE and serum/SIE solutions, indicating that the mechanisms of dissolution for each solution may be the same.  相似文献   
968.
Clathrin-mediated endocytosis at the plasma membrane is a major pathway of synaptic vesicle recycling in neurones, but little is known about the molecular machinery that orchestrates the process. The amphiphysin protein has recently emerged into the limelight since its discovery in 1992 as a synaptic vesicle-associated protein. It was subsequently found to interact in vitro with the GTPase dynamin through its SH3 domain. However, only in the past year has its role in endocytosis been confirmed, with the demonstration that the introduction of dominant-negative-acting SH3 domains into living cells causes a potent blockade of clathrin-mediated endocytosis. This, together with the discovery by several groups of a second nerve terminal-enriched amphiphysin isoform, and the finding that the two proteins heterodimerize, further suggests that the amphiphysins are closely connected with dynamin-mediated vesicle budding. This review summarizes current views in the field, and draws on data that suggest intriguing alternative roles--including possible involvement in the cytoskeleton and in tumour suppression--for certain members of the amphiphysin family.  相似文献   
969.
The original Smoking Consequences Questionnaire (SCQ; T. H. Brandon & T. B. Baker, 1991) measured college students' outcome expectancies for cigarette smoking. A version (SCQ-Adult) was needed for assessing expectancies in more typical, older, nicotine-dependent smokers. Two separate versions of the SCQ were developed and compared. Tests of construct validity provided greater support for the version comprising probability items over the version comprising subjective expected utility items. As expected, principal components analyses revealed a greater number of factors than the original SCQ suggesting that expectancies become more specific with smoking experience. All scales showed good reliability. Over the course of smoking cessation treatment, expectancies became less positive, especially for abstaining participants. Other validity tests also tended to be consistent with research on alcohol expectancies and with contemporary models of drug outcome expectancies. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
970.
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