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Power density producing damage at a probability of 0.5 (ie, damage threshold, DT-50) was determined for PMMA (with/without UV absorber) and Silicone intraocular lenses. Scattered light from a collinear diagnostic He:Ne beam was one of four damage monitors deployed to enhance the sensitivity of the system. In order of increasing laser resistance the following results were obtained: injection molded PMMA (1.9/GW/cm2) Silicone (2.63 GW/cm2) Lathe-cut PMMA (4.47 GW/cm2), Lathe-cut PMMA with UV absorber (8.32 GW/cm2), Cast-molded PMMA (12.30 GW/cm2). An analysis of variance revealed interclass differences significant at the .01 level. Cast-molded PMMA was the most laser-resistant IOL material.  相似文献   
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Notfall + Rettungsmedizin - Der plötzliche Brust- und der plötzliche Unterleibsschmerz gehören zu den häufigsten Gründen, die Patienten in die Notaufnahme führen. Das...  相似文献   
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OBJECTIVE: The purpose of this study was to determine whether the dental pulp and lesions of pulpal origin (eg, pulp polyps, periapical granulomas, and periapical cysts) exhibit receptors for the sex steroid hormones estrogen, progesterone, and androgen. STUDY DESIGN: Staining for the receptors of the hormones estrogen, progesterone, and androgen was accomplished through use of available immunohistochemical detection techniques. Pulpal tissues were obtained from freshly extracted human third molars; the other tissues were obtained from the Oral and Maxillofacial Pathology Laboratory archives. Ten samples of each tissue were processed and immunostained for these specific receptors. RESULTS: Staining for estrogen and androgen receptors was essentially negative for all cell populations examined. However, positive progesterone receptor staining of varying degrees was noted in 8 of 10 pulpal specimens. Primarily, pulpal fibroblasts and odontoblasts exhibited positive immunoreactivity. CONCLUSIONS: The results of this study suggest that although the dental pulp may be a potential target tissue for progesterone, evidence is lacking with respect to the other sex steroid hormones.  相似文献   
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BACKGROUND AND PURPOSE: Low-molecular-weight heparins and heparinoids (LMWHs) are superior to unfractionated heparin in the prevention and treatment of venous thromboembolism and acute coronary syndromes. We performed a systematic review of randomized controlled trials (RCTs) to examine the safety and efficacy of LMWH in acute ischemic stroke. METHODS: Randomized, controlled, and nonconfounded trials of LMWH in acute ischemic stroke were identified from the Cochrane Library (version 2, 1999), previous systematic reviews, and a review of publication quality relating to acute stroke trials. The authors each independently extracted data by treatment group and assessed trial quality using Cochrane Collaboration criteria. RESULTS: Eleven completed RCTs involving 3048 patients were identified; data were available from 10 of these. Four trials explicitly excluded patients with presumed cardioembolic stroke. Treatment with LMWH was associated with significant reductions in prospectively identified deep vein thrombosis (OR 0.27, 95% CI 0.08 to 0.96) and symptomatic pulmonary embolism (OR 0.34, 95% CI 0.17 to 0.69) and with increased major extracranial hemorrhage (OR 2.17, 95% 1.10 to 4.28). Nonsignificant increases in end-of-treatment (OR 1.20, 95% CI 0.86 to 1.69) and end-of-trial (OR 1.05, 95% CI 0.83 to 1.32) case fatality and symptomatic intracranial hemorrhage (OR 1.77, 95% CI 0. 95 to 3.31) were observed. End-of-trial death and disability was nonsignificantly reduced (OR 0.87, 95% CI 0.72 to 1.06). CONCLUSIONS: ++LMWHs reduce venous thromboembolic events in patients with acute ischemic stroke and increase the risk of extracranial bleeding. A nonsignificant reduction in combined death and disability and nonsignificant increases in case fatality and symptomatic intracranial hemorrhage were also observed. On the basis of the current evidence, LMWH should not be used in the routine management of patients with ischemic stroke.  相似文献   
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Until now there has no been no simple, reliable clinical test that assesses the function of the otolith organs. However, recent work has suggested the occurrence of an easily identifiable electromyographic (EMG) waveform in isometrically contracting sternomastoid muscles in response to loud clicks. This is thought to represent an otolith evoked disynaptic reflex. Equipment routinely used for evoked response audiometry (ERA) has been adapted to investigate this response. A short latency (8 ms) positive-negative EMG waveform has been recorded in 31 of 32 normal subjects. The latency of the positive peak (P1) is 11.7 ms ( sd = 0.89), and the negative peak (N1) is 20.5 ms ( sd = 1.89). It is predominantly ipsilateral, although a contralateral response was present in 35.5%. The response has also been recorded in three patients with a severe unilateral sensorineural hearing loss and normal caloric responses, and in a patient undergoing cochlear implantation for profound bilateral sensorineural hearing loss. Further work is required to delineate the value of this technique in investigating vestibular lesions.  相似文献   
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The stressed bleeding time is a simple 'global' test of haemostasis, dependent upon platelet function, rheology, thrombosis and intimal function. It could be of considerable value in clinical practice if it were shown to be predictive of vascular disease events. A stressed bleeding time test was done on 1319 men aged 55-69 years in the Caerphilly Cohort Study of Heart Disease, Stroke and Cognitive Decline. The men were followed-up and during the following 7-10 years 155 men had a myocardial infarction (MI) and 72 an ischaemic stroke. The mean bleeding time was 323 (SD 113) s. This was shorter in men who smoked by an average of 45 s, and lengthened in men who took aspirin daily by 40 s. After making statistical adjustments for numerous possible confounding factors, the relative odds (ROs) of an MI within the third of men with the longest bleeding times, compared to the third with the shortest times, was 0.90 (0.40-2.03). For ischaemic stroke, the ROs in the third of men with the longest times were 1.42 (0.39-5.21). The stressed bleeding time does not predict either MI or ischaemic stroke. It has no place in health screening.  相似文献   
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The study sought to: (1) describe the mental health and substance use profiles among participants of a specialty trafficking court program (the Succeed Though Achievement and Resilience Court); (2) describe youths' mental health and substance use treatment prior to participating in the program; and (3) examine whether abuse influences report of mental health problems and/or substance use. Retrospective case review of court files was performed on commercially sexually exploited youth who volunteered to participate in the court from 2012 to 2014 (N = 184). All participants were female. Mental health problems and report of substance use was high among this population. Substance use differed at statistically significant levels between youth with a documented abuse history compared to those with no abuse history. Substance use also differed by report of mental health problems. Unexpected findings included the high rate of hospitalization for mental health problems and relatively low substance use treatment prior to STAR Court participation. Opportunities for improvement in critical points of contact to identify commercially sexually exploited youth and address their health needs are discussed.  相似文献   
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