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991.
The performance of a 1.6 Gbit/s optical receiver employing a s.a.w. filter as a timing tank is reported. The error-rate characteristics in a p.c.m. transmission system using a 1.3 ?m In-GaAsP laser and single-mode fibres were studied. The average received optical power at a 10?9 error rate was ?28 dBm. In a 15 km transmission experiment, the receiving level was degraded by 2 dB owing to fibre dispersion. Timing phase margin of 75 degrees after 12 km transmission was confined with the self-timed receiver.  相似文献   
992.
Using eyes undergoing phacoemulsification followed by implantation of a foldable acrylic intraocular lens (IOL) designed for small-incision cataract surgery, a multi-center study was performed to compare a non-steroidal ophthalmic solution (0.1% diclofenac) to a steroidal ophthalmic solution (0.1% fluorometholone) in preventing cystoid macular edema (CME) and inducing disruption of the blood-aqueous barrier determined by laser flare cellmetry. The incidence of CME, noted in 3 out of 53 eyes (5.7%) receiving diclofenac and in 29 out of 53 eyes (54.7%) receiving fluorometholone, was significantly lower in the diclofenac group. The flare in the anterior chamber was also significantly lower in the diclofenac group; when compared between eyes with and without CME, the amount of flare was significantly higher in the former group. These findings suggest that diclofenac effectively prevents CME following cataract surgery and that CME is closely related to the breakdown of the blood-aqueous barrier.  相似文献   
993.
BACKGROUND: Although diagnostic peritoneal lavage (DPL) is a well-established, reliably objective method of diagnosis of intraperitoneal injury, it is too sensitive to be used as an indicator for emergency celiotomy. Therefore, since the development of ultrasonography and advanced computed tomographic scanners, the role of DPL has been markedly reduced. Despite such remarkable advances, however, radiologic diagnosis of intestinal injury cannot always provide definitive results, and DPL may still be valuable in such instances. We have developed a new DPL criteria specifically designed to aid in the diagnosis of intestinal injury and have evaluated its effectiveness. METHODS: From August 1988 to December 1995, we performed DPL in 250 patients with blunt abdominal trauma and analyzed the diagnostic accuracy of our new criteria. We used the standard quantitative white blood cell (WBC) criterion for detection of intestinal injury supplemented by a positive-negative borderline adjusted to WBC > or = red blood cell (RBC)/150, where RBC > or = 10 x 10(4)/mm3. RESULTS: Our criteria had a diagnostic sensitivity of 96.6% and a specificity of 99.4% for intestinal injury after exclusion of 57 patients in whom DPL was performed within 3 hours or after 18 hours from the time of injury. In 133 patients with hemoperitoneum, emergency celiotomy was performed in only 48; the remaining 85 patients with negative DPL based on the WBC criterion avoided surgery, and conservative management resulted in no complications. CONCLUSION: With the proposed criteria, DPL can be used to diagnose or exclude intestinal injury even in the presence of hemoperitoneum.  相似文献   
994.
NAD(P)H:quinone oxidoreductase 1 (NQO1) is a flavoenzyme that catalyzes two-electron reductive metabolism and detoxification of quinones and their derivatives leading to protection of cells against redox cycling and oxidative stress. To examine the in vivo role of NQO1, a NQO1-null mouse was produced using targeted gene disruption. Mice lacking NQO1 gene expression showed no detectable phenotype and were indistinguishable from wild-type mice. However, NQO1-null mice exhibited increased toxicity when administered menadione compared with wild-type mice. These results establish a role for NQO1 in protection against quinone toxicity. The NQO1-null mice are a model for NQO1 deficiency in humans and can be used to determine the role of this enzyme in sensitivity to toxicity and carcinogenesis.  相似文献   
995.
We have developed a digital real‐time simulator of Power Electronics Controllers, so‐called FACTS (Flexible AC Transmission Systems) Controllers and/or Custom Power by using MATLABTM/SIMULINKTM and dSPACETM System. This paper describes the modeling and the calculation accuracy of a UPFC (Unified Power Flow Controller) model. Hence, the developed simulator operates at a large time step, in order to improve simulation accuracy, a correction processing of the switching delay is implemented into the UPFC model. Calculation accuracy of the real‐time UPFC model is at the same level as EMTDCTM results. We confirm stable operation of the developed UPFC model by connecting a commercial real‐time digital simulator (RTDSTM). © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(1): 19–26, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20200  相似文献   
996.
Fatigue fracture mechanism maps at room temperature and 573 K for a type 304 stainless steel were constructed by correlating the crack propagation rate with information obtained on the fracture surface. Depending on the crack propagation rate, ranging from 1 × 10−6 to 1 × 10−11 m/cycle, three types of fracture surfaces were observed. One was a striation region; the second was a “featureless” fracture region, which appeared rough under scanning electron microscope (SEM) observation; and the third was crystallographic fracture region, which appeared smooth under SEM observation. The area fractions and the indexes of the fracture surfaces were quantified and identified by the etch-pit method. From the results, crack initiation and propagation mechanisms were cleared and fatigue fracture mechanism maps were constructed. The maps may be useful for investigating the cause of the fatigue failure accident of structures made of type 304 steels.  相似文献   
997.
A card form of the Halstead-Reitan Category Test was devised. Comparisons of mean total error scores and subset scores obtained from 2 groups of neurologically referred Ss showed no significant differences between the card and standard slide projection formats. Also, retest reliability assessed by presenting the 2 formats in counterbalanced order indicated similar high orders of reliability. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
998.
Traction characteristics of eight fluids of various compositions are evaluated with a four-roller machine, in which rotational speeds of mating rollers are positively controlled. The fluids tested are paraffinic and naphthenic mineral oils, liquid paraffin, polyisobutylene, and synthetic branched hydrocarbons. When the coefficient of traction is determined as a function of slide/roll ratio all fluids show essentially similar behaviour. However, different compositions have a marked effect on the values of the coefficient. These values are found to show a reasonable correlation with the estimated viscosity of each fluid at the average Hertzian pressures in the contacts  相似文献   
999.
1000.
The effect of 2 types of adrenergic blockade on the capacity of the coronaries for hypoxic dilatation was studied in open chest dogs under chloralose anesthesia. Reactive hyperemia following the temporary occlusion of the left coronary artery and the vasodilatation elicited by general arterial hypoxia served to determine the range of coronary adaptation. beta-adrenergic blockade induced by propranolol (0.3 mg/Kg i.v. or 0.05 mg/Kg intracoronarially) failed to reduce the range of hypoxic dilatation. On the other hand, the alpha-blocking agent phentolamine (0.45 mg/Kg i.v. or 0.15 mg/Kg i.c.), in association with a decrease of the vascular tone, significantly limited the coronary adaptation to hypoxia.  相似文献   
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