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Bush RL  Najibi S  Lin PH  Lumsden AB  Dodson TF  Salam AA  Smith RB  Chaikof EL  Weiss VL 《The American surgeon》2002,68(1):57-60; discussion 60-1
The last decade has represented a time of fundamental change in the treatment of abdominal aortic aneurysms (AAAs). Potentially, vascular surgeons will either acquire catheter-based skills or relinquish the care for many patients with infrarenal AAA. We investigated AAA referral patterns and method of AAA repair after the establishment of an endovascular AAA program at our institution. We conducted a retrospective review of elective AAA repairs after the initiation of an endovascular AAA program in April 1994. Six vascular surgeons performed all procedures with a clear distinction between the surgeons (n=3) who performed traditional AAA repair only and those (n=3) who managed AAAs by means of either endovascular or traditional treatment. From April 1994 through December 2000, 740 elective AAA repairs were performed. During this time the mean number of AAA repairs has been 106/year ranging from 75 to 155/year. More notable however is the steady increase in the percentage of endovascular AAA repairs from 6 per cent of all AAA repairs in 1994 to 61 per cent in 2000. During this time traditional surgeons have experienced a plateau in total AAA repairs performed per year with their number of open repairs decreasing by 36 per cent. At the same time endovascular surgeons have seen a progressive rise in total AAA cases including an increase of 200 per cent in open repairs and of 1367 per cent in endovascular repairs. Our vascular surgeons who repair AAA utilizing both endovascular and open techniques have experienced an increase in aneurysm referrals since the advent of an endovascular AAA program. Those who have not adopted endovascular skills have seen a decline in their aneurysm practice. The larger question about whether or not to embrace new technology before the availability of long-term follow-up remains unanswered.  相似文献   
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BACKGROUND.: Due to ongoing organ donor shortage, an increasing number of adult live-donor liver transplants (LDLT) are being performed. The aims of this study were to compare the incidence of ACR between recipients of live- and deceased-donor liver transplants, and to note any differences in ACR among related and unrelated living-donor recipients. METHODS.: Sixty-four adults undergoing LDLT between 1998-2001 were closely matched with a deceased recipient. Statistical comparisons in ACR between the live- and deceased-donor groups were based on the differences between the ACR rates of each LDLT patient and the corresponding matched deceased recipient. Analyses were performed separately for pairs in which the living donor was not related to the recipient, was a nonsibling relative, or was a sibling. RESULTS.: Live- and deceased-donor recipients underwent a similar number of liver biopsies. In all, 16/50 (32%) of the biopsied LDLT patients had ACR compared to 36/49 (73%) of the deceased-donor recipients. ACR rates of living donors and their deceased-donor matches did not differ significantly for the unrelated living donors, but did differ for the nonsibling related (P=0.03) and the sibling LDLT (P=0.03). The results were similar when comparing rates of high-degree ACR for unrelated, nonsibling related, and sibling pairs. High-degree ACR differences in the sibling LDLT group were significantly greater than in the nonsibling group (P=0.05). CONCLUSIONS.: Rates of ACR and high-degree ACR are decreased in living-related liver transplant recipients. This difference is likely genetically related as ACR rates are lower in recipient-donor pairs of increasing genetic similarity.  相似文献   
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Objective: The most obvious and best documented changes in speech of postlingually deafened speakers are the rate, fundamental frequency, and volume (energy). These changes are due to the lack of auditory feedback. But auditory feedback affects not only the suprasegmental parameters of speech. The aim of this study was to determine the change at the segmental level of speech in terms of vowel formants. Methods: Twenty-three postlingually deafened and 18 normally hearing speakers were recorded reading a German text. The frequencies of the first and second formants and the vowel spaces of selected vowels in word-in-context condition were compared. Results: All first formant frequencies (F1) of the postlingually deafened speakers were significantly different from those of the normally hearing people. The values of F1 were higher for the vowels /e/ (418±61 Hz compared with 359±52 Hz, P=0.006) and /o/ (459±58 compared with 390±45 Hz, P=0.0003) and lower for /a/ (765±115 Hz compared with 851±146 Hz, P=0.038). The second formant frequency (F2) only showed a significant increase for the vowel/e/(2016±347 Hz compared with 2279±250 Hz, P=0.012). The postlingually deafened people were divided into two subgroups according to duration of deafness (shorter/longer than 10 years of deafness). There was no significant difference in formant changes between the two groups. Conclusion: Our report demonstrated an effect of auditory feedback also on segmental features of speech of postlingually deafened people.  相似文献   
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Pendred syndrome, defined as the constellation of goiter, sensori-neural hearing loss, and positive perchlorate discharge test, is the most frequent cause of congenital deafness. Newly introduced diagnostic approaches to the disease are rather expensive and complicated, therefore we evaluated the value of MRI as the sole, or adjunctive diagnostic approach, and compared it with the traditional ones. Presuming the classic triad as the gold standard, we compared MRI findings in six such defined patients with six cases having goiter, hearing loss, and normal perchlorate discharge test. Our results indicated that MRI was 83.6% sensitive and 66.7% specific in patients fulfilling all three criteria (complete), while in the 'partial' group the sensitivity and specificity were 66.7% and 100% respectively. In conclusion, MRI, although impressive as an adjunctive diagnostic tool, may not replace the holistic approach, and the latter may be more convenient, cheaper, and still more accurate. However in 'partial' cases with equivocal findings, and in relatives of the patients, MRI may be a valuable diagnostic adjunct.  相似文献   
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