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71.
PURPOSE: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. METHODS: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4-6 months and glaucoma suspects every 1-2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. RESULTS: It was found that during the period under review, 7.4% (n = 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P = 0.0001) followed by 11% of primary open-angle glaucoma eyes (P = 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. CONCLUSIONS: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance.  相似文献   
72.
Discusses issues in psychotherapy with older adults and possible future developments in the field. The development of measures to assess the efficacy of various therapeutic interventions with this population is perhaps the most pressing research need. Practice can be improved in a number of ways. More clinicians must become interested in practicing with this population and not view it as a hopeless effort. Therapists must also obtain specialized training in working with the elderly, must adopt a philosophy of care consistent with the aging client, and must have a realistic understanding of what areas of intervention are perceived as most necessary to their clients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
73.
Experiments were carried out to investigate the feasibility of converting a diesel engine to hydrogen-fueled operation without providing a timed ignition system. Use was made of a glow plug and a multiple-strike spark plug. The work was done with an ASTM-CFR engine, the diesel head of which was modified to resemble the geometry of a D399 series Caterpillar diesel engine. Engine speed was 1240 rev/min. The glow plug was found to provide reliable ignition and smooth engine operation. It caused the hydrogen to ignite almost immediately upon the start of injection. Indicated mean effective pressures were on the order of 1.3φ MPa for equivalence ratios φ between 0.1 and 0.4 at a compression ratio of 18. This is significantly higher than the corresponding result obtained with diesel oil (about 0.6 φ MPa for 0.3 < ? < 0·9). Indicated thermal efficiencies were on the order of 0.4 for hydrogen and 0.20–0.25 for diesel oil. Operation with the multiple-strike spark system yielded similar values for IMEP and efficiency, but gave rise to large cycle-to-cycle variations in the delay between beginning of injection and ignition. Large ignition delays were associated with large amplitude pressure waves in the combustion chamber. The measured NOχ concentrations in the exhaust gas were of the order of 50–100 ppm. This is significantly higher than the corresponding results obtained with premixed hydrogen and air at low equivalence ratios. Compression ignition could not be achieved even at a compression ratio of 29.  相似文献   
74.
Bottlenose dolphins (Tursiops truncatus) are apex predators in coastal southeastern U.S. waters; as such they are indicators of persistent organic pollutants (POPs) in coastal ecosystems. POP concentrations measured in a dolphin's blubber are influenced by a number of factors, including the animal's sex and ranging pattern in relation to POP point sources. This study examined POP concentrations measured in bottlenose dolphin blubber samples (n = 102) from the Georgia, USA coast in relation to individual ranging patterns and specifically, distance of sightings from a polychlorinated biphenyl (PCB) point source near Brunswick, Georgia. Dolphin ranging patterns were determined based upon 5 years of photo-identification data from two field sites approximately 40 km apart: (1) the Brunswick field site, which included the Turtle/Brunswick River Estuary (TBRE), and (2) the Sapelo field site, which included the Sapelo Island National Estuarine Research Reserve (SINERR). Dolphins were categorized into one of three ranging patterns from photo-identification data. Individuals with sighting histories exclusively within one of the defined field sites were considered to have either Brunswick or Sapelo ranging patterns. Individuals sighted in both field sites were classified as having a Mixed ranging pattern. Brunswick males had the highest concentrations of PCBs reported for any marine mammal. The pattern of PCB congeners was consistent with Aroclor 1268, a highly chlorinated PCB mixture associated with a Superfund site in Brunswick. PCB levels in Sapelo males were lower than in Brunswick males, but comparable to the highest levels measured in other dolphin populations along the southeastern U.S. Female dolphins had higher Aroclor 1268 proportions than males, suggesting that the highly chlorinated congeners associated with Aroclor 1268 may not be offloaded through parturition and lactation, as easily as less halogenated POPs. Individuals sighted farther from the Superfund point source had lower Aroclor 1268 proportions.  相似文献   
75.
Thin CdS films have been grown by chemical bath (CdCl2, thiourea, ammonia) deposition (CBD) on SnO2 (TO)-coated glass substrate for use as window materials in CdS/CdTe solar cells. High-resolution transmission electron microscopy revealed grains with an average size of 10 nm. The structure was predominantly hexagonal with a high density of stacking faults. The film crystallinity improved with annealing in air. Annealing in a CdCl2 flux increased the grain size considerably and reduced the density of stacking faults. The optical transmission of the as-deposited films indicated a band gap energy of 2.41 eV. Annealing in air reduced the band gap by 0.1 eV. Annealing in CdCl2 led to a sharper optical absorption edge that remained at 2.41 eV. Similar band gap values were obtained by photocurrent spectroscopy and electroabsorption spectroscopy (EEA) using an electrolyte contact. EEA spectra were broad for the as-deposited and air-annealed samples, but narrower for the CdCl2-annealed films, reflecting the reduction in stacking fault density. Donor densities of ca. 1017 cm –3 were derived from the film/electrolyte junction capacitance.  相似文献   
76.
Strong evidence suggests that prior syntactic context affects language production (e.g., J. K. Bock, 1986). The authors report 4 experiments that used an expression-picture matching task to investigate whether it also affects ambiguity resolution in comprehension. All experiments examined the interpretation of prepositional phrases that were ambiguous between high and low attachment. After reading a prime expression with a high-attached interpretation, participants tended to interpret an ambiguous prepositional phrase in a target expression as highly attached if it contained the same verb as the prime (Experiment 1), but not if it contained a different verb (Experiment 2). They also tended to adopt the high-attached interpretation after producing a prime with the high-attached interpretation that included the same verb (Experiment 3). Finally, they were faster to adopt a high-attached interpretation after reading an expression containing the same verb that was disambiguated to the high-attached versus the low-attached interpretation (Experiment 4). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
This paper describes the ERBS-TDRSS Contact Planning System (ERBS-TDRSS CPS) that has been built to help Earth Radiation Budget Satellite (ERBS) flight operations personnel generate requests for service from the Tracking and Data Relay Satellite System (TDRSS). The ERBS-TDRSS CPS is written in the C language and runs on an IBM PC-AT. It uses a graphics interface and the Transportable Inference Engine (TIE-1) developed for NASA-(Goddard Space Flight Center) GSFC. First, ERBS-TDRSS Ground Track Orbit Prediction data are electronically transferred to the ERBS flight operations area, where, in its batch mode, the ERBS-TDRSS CPS automatically generates requests for TDRSS service (usually for one week). In this process, a series of scheduling strategies is used to generate requested events while TIE-1 determines whether each requested event is consistent with ERBS scheduling constraints. As requested events are rejected, alternative context-sensitive strategies are used to generate new requested events until a schedule is completed. In the interactive scheduling mode the ERBS planner can edit a schedule that has been previously built or choose which alternative scheduling strategies the ERBS-TDRSS CPS should use to build a schedule. Finally, a report generator builds “Schedule Requests” for each separate ERBS-TDRSS contact.  相似文献   
78.
Axonal injury (AI), as defined by amyloid precursor protein (APP) positive axonal swellings, was recorded on a series of line diagrams of standard brain sections divided into 116 sectors to provide an Axonal Injury Sector Score (AISS) ranging from 0 to 116. This sector scoring method of recording axonal damage and providing a topographic overview of AI was applied to a series of 6 mild head injury cases [Glasgow Coma Scale (GCS) 13-15] and six severe head injury cases (GCS 3-8). The AISS ranged from 4 to 107 overall and varied from 4 to 88 in the mildly injured group and 76 to 107 in the severe head injury group, supporting the concept that there is a spectrum of AI in traumatic head injury and that the AISS is a measure of the extent of AI. APP immunostaining demonstrated positive axonal swellings 1.75 h after head injury and analysis of the pattern of AI in the mild and severe head injury groups showed that axons were more vulnerable than blood vessels and that the axons in the corpus callosum and fornices were the most vulnerable of all.  相似文献   
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