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A rare case of retroperitoneal mass identified in the pilot, aged 48, is described. There has been noted the complexity of differential diagnosis between the benign and malignant process associated with the given type of tumor which led to some problems when making an expert decision. The tumor was found to be non-removable, however, considering the good clinical state of the pilot, he was permitted of flying activity which he continues to perform successfully more than 10 years. The pilot state remains good which confirms the benign character of the process. The observation is of great interest both clinically and from the flight-surgeon's appraisal standpoint. 相似文献
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CH Schoenmakers IG Pigmans E Kaptein VM Darras TJ Visser 《Canadian Metallurgical Quarterly》1993,335(1):104-108
The type III iodothyronine deiodinase (ID-III) catalyzes the inner ring deiodination and, thus, the inactivation of the thyroid hormones T4 and T3. ID-III activity in rat brain, rat placenta and embryonic chicken liver is inhibited by the affinity label N-bromoacetyl-T3 (BrAcT3) with an affinity similar to that of T3. Reaction of rat brain and placenta microsomes with BrAc[125I]T3 resulted in the extensive labeling of a 32 kDa protein (p32). However, p32 was also prominently labeled in fetal rat liver microsomes which have no ID-III activity. Labeling of p32 was not influenced by 100 microM substrate analogs or inhibitors of ID-III, some of which completely inhibit ID-III activity at 1 microM. BrAc[125I]T3 labeling of embryonic chicken liver microsomes did not reveal p32 or another protein possibly related to ID-III. In contrast to previous suggestions, it is unlikely that p32 represents ID-III or a subunit thereof. 相似文献
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Summary. A quorum system is a collection of sets (quorums) every two of which intersect. Quorum systems have been used for many applications in the
area of distributed systems, including mutual exclusion, data replication and dissemination of information. In this paper
we introduce a general class of quorum systems called Crumbling Walls and study its properties. The elements (processors) of a wall are logically arranged in rows of varying widths. A quorum in a wall is the union of one full row and a representative from every row below the full row. This class considerably
generalizes a number of known quorum system constructions. The best crumbling wall is the CWlog quorum system. It has small
quorums, of size O(lg n), and structural simplicity. The CWlog has optimal availability and optimal load among systems with such small quorum size.
It manifests its high quality for all universe sizes, so it is a good choice not only for systems with thousands or millions of processors but also for systems
with as few as 3 or 5 processors. Moreover, our analysis shows that the availability will increase and the load will decrease
at the optimal rates as the system increases in size.
Received: August 1995 / Accepted: August 1996 相似文献
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VP Kozobolis IG Pallikaris IG Tsambarlakis IG Vlachonikolis 《Canadian Metallurgical Quarterly》1997,75(6):711-715
PURPOSE: To define the frequency of development of pupillary membranes after ECCE with PC-IOL implantation, and to remove the pupillary membranes using the Nd:YAG laser. METHODS: From 400 patients who had undergone ECCE and were free from local or systemic illness affecting the blood-ocular barrier, 20 eyes developed pupillary membranes Nd:YAG laser was used to remove these pupillary membranes. RESULTS: The frequency of pupillary membranes was found to be 5% (9.8% in pex eyes and 3.3% to the non-pex eyes). Visual acuity improved in 17 eyes by 2 to 5 Snellen lines. No serious complications were observed, endothelium inclusive. CONCLUSION: Pseudoexfoliation might play a significant role in the development of postoperative pupillary membranes which could be successfully treated with the use of Nd:YAG laser. The safety of the procedure has to be evaluated in relation to the corneal endothelium damage in long-term. 相似文献
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IG De Plaen 《Canadian Metallurgical Quarterly》1997,18(4):137-139
Super-sidecut skis are wider at the tip and tail than a traditional ski, and the waist varies depending on the function of the ski. The sidecut influences the performance characteristics of the ski, making it easier to initiate a turn, carve tighter turns, and carve at slower speeds--which translates into more fun. Super-sidecut skis are more sensitive to controlling movements, so you can ski in a more balanced, centered position. There are some compromises in terms of stability and injury risk. With so much variety in super-sidecut skis, controlled population studies will be necessary to track injury trends. 相似文献
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