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In an attempt to improve the guidelines for concurrent management of concomitant abdominal aortic aneurysm (AAA) and symptomatic malignancy, a retrospective study was undertaken. A total of 186 AAA repairs were performed electively, and 25 patients (13.4%) had concurrent symptomatic malignancy from April 1986 to March 1997. Fourteen patients underwent a one-stage operation, including five abdominoperineal rectal resections, four subtotal gastrectomies, three total gastrectomies, and two right hemicolectomies. Eleven others underwent a two-stage operation, including four with total gastrectomy and left hemicolectomy followed by AAA repair, as well as two with right hemicolectomy and one with left hemicolectomy prior to AAA repair. There were no operative deaths or severe postoperative complications. Of the 25 patients, 22 (88.0%) are still alive during follow-up ranging from 8 months to 11 years. Our surgical approach to both lesions is as follows: (1) Using the transperitoneal approach alone, subtotal gastrectomy and abdominoperineal rectal resection can be safely done simultaneously. (2) Although total gastrectomy can also be performed concurrently, the approach used for each lesion is separate. (3) Colorectal resection is generally done separately. However, a one-stage operation can be performed using the thromboexclusion procedure for AAA repair in patients with right-sided colonic cancer or a temporary transverse colostomy for left-sided colorectal cancer.  相似文献   
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A novel high-efficiency concentrator based on nonimaging optics has been designed and fabricated with micromachining technique. The shape of the concentrator utilizes compound parabolic concentrator (CPC), which can concentrate the all rays that have the angles less than a critical angle &thetas;c. The theoretical concentration efficiency was calculated by ray trace simulation considering the reflectance of the concentrator's reflective layer. The metal reflection layer of reflectance 95% was formed by gold-nickel mirror plating method in a glass hole. As a result, the concentration efficiency of the concentrator was measured as 89%  相似文献   
3.
We have established a convenient synthesis process for the synthesis of[18F]haloperidol using a single-step 18F-for-Cl exchange reaction and a new elution system for the preparative high performance liquid chromatography (HPLC) using C18 bonded vinylalcohol copolymer gel (ODP) and a basic eluent. We successfully applied the product to cat-PET study and got clear images of the striatum, showing the usefulness of this synthesis.  相似文献   
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Breadth-first ray tracing is based on the idea of exchanging the roles of rays and objects. For scenes with a large number of objects, it may be profitable to form a set of rays and compare each object in turn against this set. By doing so, thrashing, due to disk access, can be minimized. We present ways to combine breadth-first methods with traditional efficient algorithms, along with new schemes to minimize accessing objects stored on disk. Experimental analysis, including comparisons with depth-first ray tracing, shows that large databases can be handled efficiently with this approach  相似文献   
5.
Electron transfer across proteins plays an important role in many biological processes, including those relevant for the conversion of solar photons to chemical energy. Previous studies demonstrated the generation of photocurrents upon light irradiation in a number of photoactive proteins, such as photosystem I or bacteriorhodopsin. Here, it is shown that Sn‐cytochrome c layers act as reversible and efficient photoelectrochemical switches upon integration into large‐area solid‐state junctions. Photocurrents are observed both in the Soret band (λ = 405 nm) and in the Q band (λ = 535 nm), with current on/off ratios reaching values of up to 25. The underlying modulation in charge‐transfer rate is attributed to a hole‐transport channel created by the photoexcitation of the Sn‐porphyrin.  相似文献   
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Polyethylene terephthalate (PET) sheets that are now widely used in beverage cans have excellent properties of formability, corrosion resistance and adhesion to steel sheets. To expand their application, we have sought to develop a new PET film laminated steel sheet for use in food cans. Content release properties are necessary for easy removal of the can contents in food can applications. However, PET film laminated steel sheets have poor content release properties. Investigations of these properties have revealed dependence on the strength of adhesion between the films and can contents. The surface free energy of PET films has been inferred to be the main factor in poor content release properties. Therefore, using films with widely diverse surface free energy values, we studied the effects of surface free energy on the content release properties of materials in contact with cans. The results showed that these properties are closely related to the surface free energy of the film material, and that materials with surface free energy of less than 23 mN/m or greater than 44 mN/m show excellent properties for processed meat products with high protein content. The material with PET film coated with mixture of polyester resin and fatty acid is the most promising material for use in food cans in this study. The work has also shown that content release properties can be expressed as a function of adhesion in water between a material and protein. Reducing adhesion can significantly improve content release properties.  相似文献   
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PURPOSE: Our aim was to study the relation between epilepsy and sleep-wakefulness cycles in the amygdala-kindling model of temporal lobe epilepsy. METHODS: Adult male Wistar rats were electrically kindled through bipolar electrodes implanted in the anterior amygdala. Polysomnographic recordings were taken before and after kindled seizures for 6 h. For the studies on the effects of a single, full-blown seizure, recordings were taken immediately after the seizure and daily thereafter until the recordings returned to baseline values. For studies on the effects of five full-blown seizures, recordings were taken immediately after the fifth seizure and then on day 1, 2, 3, 5, 7, 14, 21, and 28. RESULTS: Polysomnographic recordings taken immediately after the first full-blown seizure revealed an initial increase in the duration of deep slow-wave sleep (SII), a decrease in the light slow-wave sleep (SI) stage of non-rapid eye movement (NREM) sleep, and a decrease in the quiet wakefulness (W2) stage of wakefulness. All these parameters returned to baseline values after 24 h. The duration of rapid eye movement (REM) sleep increased and returned to the baseline value after 48 h. Five consecutive full-blown seizures caused an increase in the duration of SII from the day the seizures occured until day 28, whereas the duration of SI decreased for 72 h. The duration of REM sleep, decreased only on the day of the seizures and day 1, while decreases in the number of REM episodes were observed on the day of the seizure, day 2 and day 14. CONCLUSIONS: Our study indicates that even a single, full-blown seizure can cause alterations in the architecture of sleep-wakefulness cycles for a short duration, and that multiple seizures produce long-term effects.  相似文献   
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