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61.
Hoy FB Mueller DK Geiss DM Munns JR Bond LM Linett CE Gomez RC 《The Annals of thoracic surgery》2000,70(4):1259-1263
BACKGROUND: Early implantation of centrifugal devices in patients with postcardiotomy cardiogenic shock may provide a bridge to recovery and allow subsequent long-term survival. METHODS: Since January 1989, 62 patients were supported with centrifugal pumps because of failure to wean from cardiopulmonary bypass. Indications were postcardiotomy cardiogenic shock (PCCS) (n = 60), bridge to cardiac retransplantation (n = 1), and right ventricular failure (n = 1). Patients' ages ranged from 23 to 78 years; 40 were men (65%), and 22 were women (35%). Twenty-two patients (35%) had a left ventricular assist device; 9 patients (15%) had a right ventricular assist device; and 31 patients (50%) had a biventricular assist device. Length of support ranged from 1 day to 19 days. RESULTS: Forty-two patients (68%) were weaned successfully; 27 patients survived to discharge (44%). Complications included bleeding (n = 41, 66%), renal failure (n = 28, 45%), and respiratory failure (n = 26, 42%). Currently, 23 patients survived 10 or more years (n = 1), 6 to 10 years (n = 7), 1 to 5 years (n = 10), and less than 1 year (n = 5). CONCLUSIONS: Centrifugal pumps are available, easy to use, and relatively inexpensive. Our experience justifies their continued use as a bridge to recovery for patients with postcardiotomy cardiogenic shock, despite the availability and increasing use of more expensive devices. 相似文献
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In the search for the postulated but elusive "estrogenic bias" in patients developing endometrial cancer, several authors have suggested lack of progesterone as the common denominator. In this study 21 patients at the time of diagnosis of Stage I disease are compared to stringently matched healthy control subjects. No significant difference was found in plasma progesterone concentrations between the two groups. These results, in conjunction with other calculated estrogenic indices based on these patients, provide no evidence of lack of progesterone at the onset of clinical disease. However, the effects of long-term progesterone lack related to chronic anovulation are not excluded by these findings. 相似文献
64.
The fate of isoprene inhaled by rats: comparison to butadiene 总被引:1,自引:0,他引:1
A R Dahl L S Birnbaum J A Bond P G Gervasi R F Henderson 《Toxicology and applied pharmacology》1987,89(2):237-248
Isoprene (2-methyl-1,3-butadiene), a volatile monomer occurring in the natural environment and used in the manufacture of elastomers, is a close chemical relative of the animal carcinogen 1,3-butadiene. To obtain toxicokinetic data for inhaled isoprene, male F344 rats were exposed in groups of 30 to 14C-labeled isoprene vapor at four concentrations from 8 to 8200 ppm. The percentage of the inhaled isoprene that was metabolized decreased with increasing exposure concentration. The percentage of the total metabolites (that is, non-isoprene-retained 14C) excreted in urine and feces or expired was determined as a function of vapor concentration. About 75% of the total metabolites was excreted in urine. This was independent of inhaled isoprene concentration. After exposure to 8200 ppm, a larger percentage of the metabolites was excreted in feces than after exposure to lower concentrations. Using vacuum line techniques, blood metabolite concentrations were determined as functions of both vapor concentration and exposure duration. At one exposure concentration (1480 ppm) metabolites were measured in the nose, lungs, liver, kidney, and fat, as well as in blood. A mutagenic metabolite, isoprene diepoxide, was tentatively identified in all tissues examined. Between 0.0018 and 0.031% of the inhaled 14C label was tentatively identified as this metabolite in blood. The relative amount of the metabolites present in blood was highest for low concentrations of inhaled isoprene and for shorter exposure durations. Body fat appeared to be a reservoir for both isoprene metabolites and isoprene itself. The appearance of metabolites in the respiratory tract after short exposure durations together with low blood concentrations of isoprene indicated that substantial metabolism of inhaled isoprene in the respiratory tract may occur. 相似文献
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R. D. Harris J. P. Chalmers P. J. Henschke A. Tonkin P. Y. Popplewell A. M. Stewart A. J. Radford K. P. O'Brien M. J. Bond M. G. Harris R. J. Turnbull G. Champion E. R. Hobbin G. R. Andrews 《Internal medicine journal》1991,21(2):230-234
The aim of this study was to identify differences in the medical management and clinical outcome in a group of elderly patients admitted to a designated geriatric assessment unit (GAU) or to two general medical units (GMUs). A prospective randomised controlled trial was undertaken in 267 patients aged 70 years and over (mean age = 78.3 years). Following discharge from hospital, patients were followed up at three monthly intervals for a total of 12 months. At the time of discharge, no significant differences were found in inpatient management, length of stay, mortality rates, discharge rates to institutional care or utilisation of community services in patients admitted to the GAU and the GMUs. Similarly, no significant differences were found at three, six, nine, and 12 month follow up in case fatality, activities of daily living indices, mental health status, rates of institutional referral and the level of community service support in patients admitted to the GAU and the GMUs studied. These findings do not show any advantage for the unselected 70 + acutely ill elderly patient who is admitted to a designated geriatric assessment unit rather than to a general medical unit. Therefore, an admission policy to GAU, based solely on age 70 + is medically inappropriate and cost-inefficient. Evidence from other sources suggests that an age cohort of acutely admitted patients beyond 80 years may well have returned more optimistic findings for the GAU. In future, GAUs will require a more selective admission policy to maximise the benefits of their rehabilitative and interdisciplinary approach. (Aust NZ J Med 1991; 21: 230–234.) 相似文献
70.
Urbina EM Srinivasan SR Kieltyka RL Tang R Bond MG Chen W Berenson GS 《Atherosclerosis》2004,176(1):157-164
Decreased arterial elasticity, an independent risk factor for cardiovascular (C-V) disease, is associated with C-V risk factors in middle-aged and older individuals. However, information is limited in this regard in young adults. This aspect was examined in a community-based sample of 516 black and white subjects aged 25-38 years (71% white, 39% male). The common carotid artery elasticity was measured from M-mode ultrasonography as Peterson's elastic modulus (Ep) and relative wall thickness-adjusted Young's elastic modulus (YEM). Blacks and males had higher Ep (P < 0.05); males had higher YEM (P < 0.0001); and blacks had higher wall thickness (P < 0.01). For the entire sample adjusted for race and gender both Ep and YEM correlated significantly (P < 0.05-0.0001) with age, BMI, waist, systolic and diastolic blood pressures, heart rate, product of heart rate and pulse pressure, triglycerides, total cholesterol to HDL cholesterol ratio, insulin and glucose. In a multivariate regression model that included hemodynamic variables, systolic blood pressure, product of heart rate and pulse pressure, age, triglycerides, BMI, and male gender (for YEM only) were independent correlates of Ep (R2 = 0.38) and YEM (R2 = 0.25). When the hemodynamic variables were excluded from the model, age, triglycerides, BMI, black race (Ep only), male gender, parental history of hypertension, HDL cholesterol (inverse association), and insulin (marginal significance) remained independent correlates of Ep (R2 = 0.20) and YEM (R2 = 16). Both Ep and YEM increased (P for trend P < 0.0001) with increasing number of independent continuous risk factors (defined as values above or below the age, race, and gender-specific extreme quintiles) that were retained in the regression models. The observed increasing arterial stiffness (or decreased elasticity) with increasing number of risk factors related to insulin resistance syndrome in free-living, asymptomatic young adults has important implications for prevention. 相似文献