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81.
Favorable results of coronary artery bypass grafting in patients older than 75 years 总被引:2,自引:0,他引:2
K A Horvath V J DiSesa P S Peigh G S Couper J J Collins L H Cohn 《The Journal of thoracic and cardiovascular surgery》1990,99(1):92-5; discussion 95-6
There is controversy whether the short-term and long-term results of coronary artery bypass grafting in elderly patients justify performing the procedure. Between January 1977 and December 1986, 4580 patients underwent coronary artery bypass grafting, of whom 222 (4.9%) were 75 years old or older (mean 77 years). There were 143 men and 79 women and 139 (63%) were in New York Heart Association class IV. One hundred forty-six patients (66%) had had at least one preoperative myocardial infarction. Myocardial revascularization was performed under emergency conditions in 17 patients (18%). The mammary artery was used in 43%, 96% of the patients received two or more grafts. The mean number of bypass grafts was 3.1 per patient. The overall hospital mortality rate was 10.8% (24/222), 3.6% for elective procedures, 14.9% in urgent cases, and 35% in emergencies. In contrast, the overall early mortality rate was 3.1% in 4358 patients less than 75 years old. Complications occurred in 83 patients (37%). Of the patients discharged from the hospital, 198 were followed up for a mean of 48 months (1 to 130). Actuarial probability of survival was 75% at 48 months. Postoperatively 70% were in New York Heart Association class I or II and only 21% were rehospitalized for cardiac problems. During the follow-up period 77% of the patients were free from angina, and of those experiencing angina the mean time from operation to the first episode was 75 months. Although elderly patients have a somewhat increased operative mortality rate, particularly if operated on urgently or emergently, long-term survival and freedom from angina are excellent and justify continued performance of coronary bypass grafting in selected patients over 75 years of age. 相似文献
82.
Aseem Vashist Dorothea Collins Yogendra Prasad Steve Blum Eliot N Heller 《Medical science monitor》2007,13(9):CR386-CR390
BACKGROUND: Myocardial perfusion imaging (MPI) is a well-established diagnostic method for evaluation and risk stratification of coronary artery disease (CAD).We undertook this study to validate both the positive predictive value (when compared to cardiac catheterization) and the prognosis afforded by MPI in a group of minority women patients. MATERIAL/METHODS: The database of our Nuclear Imaging and Catheterization Laboratory was retrospectively queried for consecutive minority (African-American, Hispanic and Asian) women patients who underwent MPI and cardiac catheterization within 90 days of each other. Patients with recent revascularization were excluded. Attenuation/scatter correction was utilized in the final interpretation of the study. RESULTS: Of the 54 women patients who underwent MPI, 7 underwent exercise stress testing, 26 had stress testing with adenosine, 18 with dipyridamole and 3 with dobutamine. Eighteen patients (53%) had same number of vessels predicted by MPI and coronary angiography (7 patients with triple vessel disease, 7 with 2-vessel disease and 4 with single vessel disease). Five (3 with intermediate and 2 with high risk scans) out of the 54 patients (9.3%) were dead at 2 years. The sensitivity, specificity and positive predictive value of MPI as compared to angiography were 87.2%, 26.7%, 75.6% and 44.4% respectively. CONCLUSIONS: The sensitivity of MPI in this group of patients is comparable to the general population though the specificity is lower in spite of using attenuation and scatter correction. Low risk perfusion scan signifies favorable prognosis at 2 years with regards to mortality. 相似文献
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85.
B Kalderon R M Dixon B Rajagopalan P W Angus R D Oberhaensli J E Collins J V Leonard G K Radda 《Pediatric research》1992,32(1):39-44
An oral load of 20 mg/kg galactose produces significant changes in the 31P magnetic resonance spectrum of the liver of a galactosemic patient. The peak at 5.2 ppm (which includes inorganic phosphate and galactose-1-phosphate) increased on two occasions to about twice its original size 60 min after galactose administration. An oral load of 10 mg/kg galactose given to a second patient produced no discernible changes at 30 min. We have also used an animal model of galactose intolerance, in which galactose metabolism in rats was blocked by the acute administration of ethanol. Studies in vivo and in vitro showed that the increase in the peak at 5.2 ppm was largely due to galactose-1-phosphate. We have shown in this preliminary study that small amounts of galactose can produce significant elevation of hepatic galactose-1-phosphate, which can be detected by 31P magnetic resonance spectroscopy. 相似文献
86.
S W Wright R R Harris R J Collins R L Corbett A M Green E A Wadman D G Batt 《Journal of medicinal chemistry》1992,35(17):3148-3155
The synthesis, biological evaluation, and structure-activity relationships of a series of 1-(pyridylphenyl)-1-phenyl-2-imidazolylethanols are described. These compounds show potent dose-dependent topical antiinflammatory activity in murine models of skin inflammation. This effect is likely due to inhibition of cytochrome P450 and consequent reduction in levels of 12R-HETE in the skin. These compounds were examined for their ability to inhibit the oxidative metabolism of arachidonic acid; they specifically inhibit the formation of prostacyclins in mouse macrophages. To study the effects of structure on the in vivo activity, three general features of the molecules were varied: the position of attachment of the pyridine nucleus (A), the second aromatic residue (B), and the nitrogen base on the ethanol chain (C). 1-[4-(4-Pyridyl)phenyl]-1-(4-fluorophenyl)-2- imidazolylethanol (2a, DuP 983) shows a very attractive profile of antiinflammatory activity and has been selected for clinical evaluation as a topical antiinflammatory agent. 相似文献
87.
Clinical and laboratory findings are described in the case of a patient with a vein of Galen aneurysm who presented with recurrent aseptic meningitis for which no etiology could be identified. The patient subsequently developed thalamic and intraventricular hemorrhage associated with partial thrombosis of the dilated vein of Galen. Review of the literature revealed no previously reported association of these conditions. Recurrent cerebral venous thrombosis involving the fistula is hypothesized as the cause of repeated inflammatory reactions near the subarachnoid space. More extensive thrombosis may then have precipitated the hemorrhage. 相似文献
88.
P W Lepinski T S Thielke D M Collins A Hanson 《American journal of hospital pharmacy》1986,43(11):2771-2779
Unit dose and traditional drug distribution systems were compared in a 352-bed long-term-care facility by analyzing nursing time, medication-error rate, medication costs, and waste. Time spent by nurses in preparing, administering, charting, and other tasks associated with medications was measured with a stop-watch on four different nursing units during six-week periods before and after the nursing home began using unit dose drug distribution. Medication-error rate before and after implementation of the unit dose system was determined by patient profile audits and medication inventories. Medication costs consisted of patient billing costs (acquisition cost plus fee) and cost of medications destroyed. The unit dose system required a projected 1507.2 hours less nursing time per year. Mean medication-error rates were 8.53% and 0.97% for the traditional and unit dose systems, respectively. Potential annual savings because of decreased medication waste with the unit dose system were $2238.72. The net increase in cost for the unit dose system was estimated at $615.05 per year, or approximately $1.75 per patient. The unit dose system appears safer and more time-efficient than the traditional system, although its costs are higher. 相似文献
89.
L O''Donnell N O''Meara D Owens A Johnson P Collins G Tomkin 《Journal of the Royal Society of Medicine》1987,80(6):339-342
Changes in plasma catecholamines, lipoproteins and dietary intake were examined in 13 medical students during a 3-month period prior to their examinations, and in 12 controls. In the medical students mean +/- s.e.(mean) plasma cholesterol increased over the study period (3.98 +/- 0.16 v. 4.26 +/- 0.16 mmol/l, P less than 0.05) and this was reflected by a rise in low-density lipoprotein cholesterol (2.53 +/- 0.15 v. 2.71 +/- 0.17 mmol/l, P less than 0.05). Both supine adrenaline (0.45 +/- 0.05 v. 0.70 +/- 0.07 nmol/l, P less than 0.01) and noradrenaline (2.74 +/- 0.18 v. 3.40 +/- 0.31 nmol/l, P less than 0.05) increased over this period. Apart from a decline in the modest alcohol consumption (9.1 +/- 3.45 v. 2.6 +/- 1.4 g/day, P less than 0.02) there was no change in dietary intake in the medical students. There were no significant changes in plasma catecholamines, lipoproteins or dietary intake in control subjects over the study period. Changes in catecholamines and lipoproteins occurring in association with chronic psychological stress may contribute to the increased coronary heart disease mortality associated with Type A behaviour and stressful life events. 相似文献
90.
Randomised controlled trial of ranitidine versus omeprazole in combination with antibiotics for eradication of Helicobacter pylori. 总被引:2,自引:0,他引:2 下载免费PDF全文
T. C. Tham J. S. Collins C. Molloy J. M. Sloan K. B. Bamford R. G. Watson 《The Ulster medical journal》1996,65(2):131-136
This study compared high dose ranitidine versus low dose omeprazole with antibiotics for the eradication of H pylori. 80 patients (mean age 48 years, range 18-75) who had H pylori infection were randomised in an investigator-blind manner to either a two-week regime of omeprazole 20 mg daily, amoxycillin 500 mg tid and metronidazole 400 mg tid (OAM), or ranitidine 600 mg bd, amoxycillin 500 mg tid and metronidazole 400 mg tid (RAM), or omeprazole 20 mg daily and clarithromycin 500 mg tid (OC), or omeprazole 20 mg daily and placebo (OP). H pylori was eradicated in 6 of 19 patients in the OAM group (32%); 8 of 18 in the RAM group (44%), 4 of 15 in the OC group (27%); none of 18 in the OP group (0%). [< P0.005 for OAM, RAM, OC vs OP; P = N.S. between OAM, RAM, OC]. Overall metronidazole resistance was unexpectedly high at 58%. Eradication rates in metronidazole sensitive patients were 71% (5/7) and 100% (3/3) for OAM and RAM respectively. In conclusion, H pylori eradication rates using high dose ranitidine plus amoxycillin and metronidazole may be similar to that of low dose omeprazole in combination with the same antibiotics for omeprazole with clarithromycin. Overall eradication rates were low due to a high incidence of metronidazole resistance but were higher in metronidazole-sensitive patients. Even high dose ranitidine with two antibiotics achieves a relatively low eradication rate. These metronidazole-based regimens cannot be recommended in areas with a high incidence of metronidazole resistance. 相似文献