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51.
GS Treiman PA Schneider PF Lawrence WC Pevec RL Bush L Ichikawa 《Canadian Metallurgical Quarterly》1998,28(1):104-12; discussion 113-4
OBJECTIVE: This study was undertaken to determine the results and complications of stents placed for initially unsuccessful or complicated iliac percutaneous transluminal angioplasty (PTA), the effect of location (external iliac or common iliac) on outcome, and the influence of superficial femoral artery patency on benefit. DESIGN: From 1992 through 1997, 350 patients underwent iliac artery PTA at the authors' institutions. Of this group, 88 patients (88 arteries) had one or more stents placed after PTA (140 stents in total) for residual stenosis or pressure gradient (63 patients), iliac dissection (12 patients), long-segment occlusion (10 patients), or recurrent stenosis (3 patients). Thirty patients required the placement of more than one stent. The indications for PTA in these 88 patients were claudication (48 patients) and limb-threatening ischemia (40 patients). Forty-seven patients had stents placed in the common iliac, 29 patients had stents placed in the external iliac, and 12 patients had stents placed in both. Seventy-one arteries (81%) were stenotic, and 17 (19%) were occluded before PTA. Sixty-six arteries were treated by interventional radiologists, 15 by a vascular surgeon, and 7 jointly. MAIN OUTCOME MEASURE: Criteria for success included (1) increase of at least one clinical category of chronic limb ischemia from baseline or satisfactory wound healing, (2) maintenance of an ankle/brachial index increase of more than 0.10 above the preprocedure index, and (3) residual angiographic stenosis less than 25% and, for patients with pressure gradient measurements, a residual gradient less than 10 mm Hg. RESULTS: Stent placement was accomplished in all 88 patients with 16 (18%) major complications. Mean follow-up was 17 months (range, 3 to 48 months). By life-table analysis, success was 75% at 1 year, 62% at 2 years, and 57% at 3 years. No cardiovascular risk factor or independent variable was statistically significant in predicting success. There was no difference in success rates for common iliac or external iliac lesions. Superficial femoral artery patency did not correlate with outcome. CONCLUSIONS: Although stents can eliminate residual lesions and arterial dissection, these patients are likely to require adjuvant or subsequent procedures to attain clinical success. By controlling the PTA complication and treating the emergent problem, stents may allow for subsequent elective intervention. 相似文献
52.
DS Lotstein MM Ward TM Bush RE Lambert R van Vollenhoven CM Neuwelt 《Canadian Metallurgical Quarterly》1998,25(9):1720-1729
OBJECTIVE: Health outcomes of patients with chronic illnesses are commonly worse in people of lower socioeconomic status (SES). We investigated psychosocial factors that may mediate the relationship between SES and measures of morbidity in women with systemic lupus erythematosus (SLE). METHODS: We collected information on SES, psychosocial factors, and health status in a cross sectional survey of 100 women with SLE. SES was rated using the Hollingshead Two-Factor Index, a weighted average of years of formal education and occupational prestige (higher Hollingshead Index=lower SES). Health status measures included the Health Assessment Questionnaire Disability Index (HAQ), the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACR), the Systemic Lupus Activity Measure (SLAM), and the SLE Disease Activity Index (SLEDAI). Potential mediators consisted of 18 environmental, medical care, social, psychological, and behavioral factors. RESULTS: Patients with higher Hollingshead Indexes (lower SES) had more functional disability as measured by the HAQ (r=0.22: p=0.03) and more cumulative organ damage as measured by the SLICC/ACR Damage Index (r = 0.19; p=0.06). SES was not related to either the SLAM or SLEDAI. Significant univariate associations were present between the Hollingshead Index and 10 potential mediating variables: household crowding, insurance status, organizational barriers to medical care, depression, health locus of control by powerful others, SLE knowledge, social support, marital status, body mass index, and regular alcohol use. However, in multiple linear regression analyses, only 3 of these variables modified the relationship between Hollingshead Index and the HAQ: more severe depression scores, higher body mass index, and more restricted access to medical care. More severe depression and greater locus of control by powerful others tended to mediate the relationship between low SES and greater organ damage. CONCLUSION: SES is related to morbidity in women with SLE. There are identifiable and potentially modifiable mediators of this relationship. 相似文献
53.
Reconstructions of family relationships: Parent–child alliances, personal distress, and self-esteem.
The aim of this study was to operationalize the structure of family relationships and examine how women's reconstructions of various family patterns during childhood and adulthood relate to their levels of depression, anxiety, and self-esteem. Using a sample of 93 women, ages 19 to 22, two family patterns emerged: (a) father-daughter alliance (FDA), whereby fathers seek intimacy and affection from their daughters instead of their wives and have emotionally distant marriages; and (b) mother-daughter triangulation (MDT), characterized by conflicted marriages whereby daughters are caught between their battling parents and mothers seek intimacy from their daughters instead of their husbands. Regression estimates suggest that childhood FDA significantly contributes to depression, anxiety, and low self-esteem even after controlling for the effects of childhood physical abuse and current FDA. Current MDT contributes to anxiety. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
Tazobactam was shown to be a potent inhibitor of group 1, 2a, 2b, and 2b' beta-lactamases. Extended kinetic studies with class A and C serine beta-lactamases showed that the PC1, TEM-2, and P99 enzymes all were reversibly inhibited prior to inactivation of the enzymes. The CcrA metallo-beta-lactamase was less well inhibited, with a 50% inhibitory concentration at least 3 orders of magnitude less favorable than those for most serine beta-lactamases. The numbers of hydrolytic turnovers of tazobactam before inactivation were 2 for PC1, 125 for TEM-2, 50 for P99, and 4,000 for the CcrA enzyme. In spectral studies, transient intermediates were formed after reaction of tazobactam with the PC1, TEM-2, and CcrA beta-lactamases, corresponding to enzyme-associated intermediates responsible for hydrolysis of tazobactam. Chromophores absorbing at 270 nm (CcrA) and 288 nm (TEM-2 and PC1) were observed for these reaction intermediates. The P99 cephalosporinase formed a stable complex with a UV maximum at 295 nm. Incubation of tazobactam with all of the enzymes resulted in accumulation of a tazobactam reaction product with a short-wavelength absorbance. This product has characteristics similar to those of the major eucaryotic metabolite of tazobactam. Possible reaction mechanisms are presented to explain the findings. In conclusion, both serine-based and metallo-beta-lactamases were irreversibly inactivated by tazobactam following an initial transient inhibition phase. 相似文献
55.
56.
Administered 2 forms of the Stroop Color-Word Interference Test and 3 scales derived from the MMPI to 26 male and 25 female undergraduates. Results raise questions about traditional interpretations of the color-word test as conflict-free measure of cognitive style and about the degree to which cognitive ability measures are saturated with modality-specific variance that is ordinarily overlooked. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Pendergrass Virginia E.; Kimmel Ellen; Joesting Joan; Pettersen Joyce; Bush Endilee 《Canadian Metallurgical Quarterly》1976,31(1):36
Presents a comprehensive discussion of the problems of women who actively challenge sex discrimination in their work and in consequence face lonely, expensive, and emotionally trying experiences. The steps by which a woman reaches the point of active protest, the institutional responses she may meet, and the countermoves open to her, are described. Special attention is given to the attitudes of unions, to legislation and the conduct of legal suits, to the type of support needed from a personal counselor during the stages of the discrimination action,and to the special problems of Black women, who are in double jeopardy, from racism and sexism. Numerous practical strategies are suggested. (46 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
R.J. Colchin C.E. Bush G.L. Jahns J.F. Lyon M. Murakami R.V. Neidigh D.L. Shaeffer 《Journal of Nuclear Materials》1976
The ORMAK tokamak has been in operation since 1971, and surface impurities problems have been pursued from the beginning. Surface studies of materials removed from ORMAK have revealed the presence of C, O, and Fe. These are also the principal impurities observed spectroscopically in plasma discharges, although numerous other elements are present in lesser amounts. Spectroscopy, X-ray measurements, plasma resistance, and fast ion scattering have been used in an effort to determine Zeff, the effective nuclear charge ot plasma ions. All four measurements have practical difficulties leading to relatively large experimental error limits. Oxygen discharge prc-cleaning has allowed ORMAK discharges to reach higher currents and correspondingly higher ion and electron temperatures; spectroscopic studies reveal a lower level of contaminants, particularly C and N. Power measurements indicate that most of the input power strikes the walls, mostly as radiation. By varying operating parameters it is found that . 相似文献
59.
M. J. Bush 《Computers & Chemical Engineering》1978,2(4):143-151
The computer simulation of wastewater treatment systems is finding increasingly wide application. Simulation studies of complete municipal waste treatment plants have been successfully accomplished. This paper describes an attempt to simulate the operation of the Kitchener, Ontario, Waste Treatment plant taking data from the last six months of 1975. It is shown that, provided some parameter values are taken from the actual plant, it is possible to closely match the mean monthly performance of the system. Steady-state mathematical models of the major waste treatment units are presented together with a discussion of the structure and operation of the SEPSIM computer program. Detailed cost relationships for a complete municipal waste treatment plant are also shown. 相似文献
60.
S. H. Bush C. A. Siebert 《JOM Journal of the Minerals, Metals and Materials Society》1954,6(11):1269-1271
Isothermal temper-embrittlement studies were conducted on a 5140 steel at various temperatures for times as long as 3000 hr. Specimens from the embrittled steel were subjected to impact tests, metallographic examination, microhardness, and lattice-parameter measurements. 相似文献