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31.
Femoral artery pseudoaneurysms (PSA or false aneurysm) develop in about 1% of patients undergoing procedures that require femoral artery cannulation. PSA prolong hospitalization, consuming health-care resources, and result in significant morbidity. We designed a study to review the prevalence, risk factors, and treatment of PSA. We performed a retrospective, case-controlled study of patients diagnosed with PSA at a large, urban, tertiary-care teaching hospital. We reviewed 48 patients with PSA for our study. The estimated prevalence of PSA was 0.28%, with identical rates found for procedures done in the interventional radiology department and in the cardiac catheterization suite. Logistic regression identified three independent risk factors for developing PSA: being female (odds ratio 2.62), having an intervention performed (odds ratio 3.22), and not having a closure device used (odds ratio 10.2). Patients with PSA had longer hospital length of stay than that of patients without PSA. We found no statistically significant difference in failure or complication rates for the four treatment options and that spontaneous resolution of PSA does not correlate with its size. Thrombin injection and observation are effective, low-complication treatment options. 相似文献
32.
Comparison of orthorhombic and alpha-two titanium aluminides as matrices for continuous SiC-reinforced composites 总被引:1,自引:0,他引:1
P. R. Smith J. A. Graves CG. Rhodes 《Metallurgical and Materials Transactions A》1994,25(6):1267-1283
The attributes of an orthorhombic Ti aluminide alloy, Ti-21Al-22Nb (at. pct), and an alpha-two Ti aluminide alloy, Ti-24Al-11Nb
(at. pct), for use as a matrix with continuous SiC (SCS-6) fiber reinforcement have been compared. Foil-fiber-foil processing
was used to produce both unreinforced (“neat”) and unidirectional “SCS-6” reinforced panels. Microstructure of the Ti-24A1-11Nb
matrix consisted of ordered Ti3Al (α
2) + disordered beta(β), while the Ti-21 Al-22Nb matrix contained three phases: α2, ordered beta (β
0), and ordered orthorhombic(O). Fiber/ matrix interface reaction zone growth kinetics at 982 °C were examined for each composite system. Although both systems
exhibited similar interface reaction products(i.e., mixed Ti carbides, silicides, and Ti-Al carbides), growth kinetics in theα
2 +β matrix composite were much more rapid than in theO +β
0 +α
2 matrix composite. Additionally, interfacial reaction in theα
2 +β} composite resulted in a relatively large brittle matrix zone, depleted of beta phase, which was not present in theO +β
0+α
2 matrix composite. Mechanical property measurements included room and elevated temperature tensile, thermal stability, thermal
fatigue, thermo-mechanical fatigue (TMF), and creep. The three-phase orthorhombic-based alloy outperformed the α2+β alloy in all of these mechanical behavioral areas, on both an absolute and a specific(i.e., density corrected) basis. 相似文献
33.
More inpatient hospital days are used for the care of diabetic foot infection than for any other diabetic sequela. Both the number of lower extremity amputations and the overall treatment cost of treating diabetic infections may be reduced by using a team approach in the care of the infected diabetic pedal wound. The authors propose an evaluation and treatment protocol of infected pedal ulcerations in an urban, community teaching institution when admitted to an established, multidisciplinary diabetic foot care team. The hospital course of 111 patients admitted with a primary diagnosis of infected pedal ulceration are retrospectively reviewed. Results revealed an average-length hospital stay of 7.4 days with a 96% limb-salvage rate. The authors suggest that in the treatment of the infected pedal wound, a diabetic foot care team with a well developed treatment protocol may yield a consistently favorable outcome and a cost-effective hospital course. 相似文献
34.
35.
CG Moertel TR Fleming JS Macdonald DG Haller JA Laurie 《Canadian Metallurgical Quarterly》1993,11(12):2386-2390
PURPOSE: To determine the frequency and nature of hepatic toxicity associated with fluorouracil (5-FU) plus levamisole adjuvant therapy. PATIENTS AND METHODS: All patients had resection of stage II or stage III colon cancer and were randomized to receive observation only, levamisole alone, or 5-FU plus levamisole. Serial liver function studies were documented in 1,025 patients who did not develop recurrence during the year of therapy. RESULTS: One hundred forty-nine (39.6%) of 376 patients treated with 5-FU plus levamisole showed laboratory abnormalities consistent with hepatic toxicity, compared with 16.3% of 251 patients treated with levamisole alone and 16.1% of 398 untreated controls. Most common was elevation of alkaline phosphatase, frequently accompanied by elevations of transaminase or serum bilirubin. Characteristically, these changes were mild, not associated with symptoms, and resolved when therapy was stopped. In some instances, they were associated with elevated carcinoembryonic antigen (CEA) tests or with fatty liver seen on computed tomographic (CT) scan or liver biopsy. CONCLUSION: Mild and reversible hepatotoxicity is a common consequence of 5-FU plus levamisole adjuvant therapy, but this is only rarely symptomatic. However, the oncologist should be alert to this phenomenon, since the associated laboratory and imaging findings may simulate those associated with hepatic metastasis. 相似文献
36.
RA Armstrong 《Canadian Metallurgical Quarterly》1996,72(3):171-191
Prostaglandins (PGs) and thromboxanes are important modulators of platelet activation, and there is strong evidence to support the existence of distinct thromboxane, prostacyclin, PGD2 and PGE2 receptors on the platelet plasma membrane. In this review, each of these platelet prostanoid receptors is discussed in detail, with respect to their receptor pharmacology, molecular biology and signal transduction, and as to any therapeutic implications of the development of specific agonists and/or antagonists. In addition, it considers the possibility that there are separate vascular receptors for 8-epi PGF2 alpha, which are not present on the platelet. 相似文献
37.
A Ménard R Amouri M Michel F Marcel A Brouillet J Belliveau C Geny L Deforges C Malcus-Vocanson M Armstrong O Lyon-Caen B Mandrand T Dobránsky F Rieger H Perron 《Canadian Metallurgical Quarterly》1997,413(3):477-485
Utilizing cultured lenses from normal and homozygous glutathione peroxidase (GSHPx-1) knockout mice and inhibitors for GSSG Reductase (GSSG Red), 1,3-bis(2-chlorethyl)-1-nitrosourea (BCNU) and catalase (Cat), 3-aminotriazole (3-AT), the ability to degrade H2O2 was examined at two H2O2 concentrations, 300 microM and 80 microM. It was found that GSHPx-1 contributed about 15% to the H2O2 degradation. The Cat contribution was concentration dependent being about 30% at 300 microM H2O2 and approximately 8% to 15% at 80 microM H2O2. GSH loss measured as nonprotein thiol (NP-SH) was shown to be linked to most of the remaining H2O2 degradation accounting for about 54% to 72% of the H2O2 degradation at 300 microM and 80 microM, respectively. However, based on evaluation of the ability of GSH to nonenzymatically degrade H2O2, it can only account for about 36% at 300 microM and 19% at 80 microM H2O2 of the observed lens H2O2 degradation. It is, therefore, concluded that lens GSH must be involved in other reactions either directly or indirectly related to H2O2 degradation. 相似文献
38.
CG Brilla 《Canadian Metallurgical Quarterly》1997,115(22-23):41-43
In a 63-year-old woman with longstanding type I diabetes mellitus, CAD and chronic heart failure, a subacute myocardial infarction developed, together with decompensation of cardiac function and diabetes and concurrent pneumonia. Acute heart failure with acute renal failure on top of diabetic nephropathy, and interstitial pulmonary edema was initially treated with hemofiltration and catechol amines together with antibiotic and perfusor-regulated insulin therapy, and systemic heparinization. Subsequent chronic treatment with digitalis, acetyl salicylic acid, insulin and a combination of an ACE inhibitor and a loop diuretic resulted in an improvement of heart failure to NYHA functional class II where PTCA of coronary multi-vessel disease could be performed with low risk. 相似文献
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