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排序方式: 共有838条查询结果,搜索用时 15 毫秒
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West SG Gebauer SK Kay CD Bagshaw DM Savastano DM Diefenbach C Kris-Etherton PM 《Hypertension》2012,60(1):58-63
Nut consumption reduces cardiovascular risk, and reductions in blood pressure and peripheral vascular resistance may be important mediators of this relationship. We evaluated effects of pistachios on flow-mediated dilation and blood pressure response to acute stress. Twenty-eight adults with dyslipidemia completed a randomized, crossover, controlled-feeding study. All of the meals were provided and calories were controlled. After 2 weeks on a typical Western diet (35% total fat and 11% saturated fat), test diets were presented in counterbalanced order for 4 weeks each, a low-fat control diet (25% total fat and 8% saturated fat), a diet containing 10% of energy from pistachios (on average, 1 serving per day; 30% total fat and 8% saturated fat), and a diet containing 20% of energy from pistachios (on average, 2 servings per day, 34% total fat and 8% saturated fat). None of the resting hemodynamic measures significantly differed from pretreatment values. When resting and stress levels were included in the repeated-measures analysis, average reductions in systolic blood pressure were greater after the diet containing 1 serving per day versus 2 servings per day of pistachios (mean change in systolic blood pressure, -4.8 vs -2.4 mm Hg, respectively; P<0.05). After the higher dose, there were significant reductions in peripheral resistance (-62.1 dyne · s × cm(-5)) and heart rate (-3 bpm) versus the control diet (P<0.0001). These changes were partially offset by increases in cardiac output. There was no effect of diet on fasting flow-mediated dilation. Reductions in peripheral vascular constriction and the resulting decrease in hemodynamic load may be important contributors to lower risk in nut consumers. 相似文献
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AP Mishreki E Lim P Cranefield S Pascoe S Jackson DA Stell 《Annals of the Royal College of Surgeons of England》2013,95(5):349-352
Introduction
The results of surgical resection and palliative chemotherapy use in hilar cholangiocarcinoma (HC) have been well publicised but the proportion of patients able to undergo these treatments and the comparative outcomes in a population of patients with HC are less well known.Methods
Patients with HC were identified by review of all patients undergoing percutaneous cholangiography over a nine-year period (2002–2010) in a tertiary facility. The treatment undertaken and outcomes were recorded.Results
Overall, 68 patients were identified (37 female) with a median age of 70 years. Forty-five (66%) were treated solely by insertion of a metal stent (median survival 4.73 months) and nine (13%) also received palliative chemotherapy (median survival 13.7 months). Persisting jaundice after stent insertion was noted in 18 of 35 patients (51%) tested within one month of death. Fourteen patients (21%) underwent surgical resection (median survival 20.2 months).Conclusions
Patients undergoing surgical resection had significantly longer survival than those receiving only a palliative stent but not compared with those also receiving palliative chemotherapy, with short-term follow-up. Only a third of patients, however, receive active treatment (surgery or chemotherapy) and improvements in long-term biliary palliation are needed. 相似文献26.
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Bagshaw SM Baldwin I Fealy N Bellomo R 《The International journal of artificial organs》2007,30(5):434-440
BACKGROUND: The reliability and safety of continuous renal replacement therapy (CRRT) machines have improved, yet there still remains the potential for fluid balance errors to occur during treatment. METHODS: In vitro testing of two Kimal Hygieia CRRT machines (Plus and Ultima) was performed. Normal saline to simulate the blood circuit and standard bicarbonate-based fluid for replacement were used. All tests were performed in CVVH mode at four ultrafiltration (UF) rates. The testing was based on creation of a voluntary fluid balance error by clamping the line that fills the replacement fluid chamber to stop flow to the (simulated) patient. The time to alarms and fluid balance errors were recorded. The alarms were overridden and the accumulated fluid balance error allowed by the machine was determined. RESULTS: The alarm occurred approximately 1 minute after the replacement fluid line was clamped at all UF rates. There was no limit to the number of times the alarm could be overridden and the accumulated negative fluid balance was proportional to the prescribed UF rate. After the replacement fluid chamber was allowed to re-fill, the machine attempted to correct the fluid deficit and consistently delivered excess fluid to generate a positive fluid balance error. CONCLUSIONS: The Hygieia machines appear designed with appropriate alarm and safety features. However, simulated fluid balance errors raise caution for operators. Clinicians and nurses need to understand the clinical implications of alarm overrides. Fluid balance errors caused by failure to acknowledge and correct replacement fluid failure alarms may cause harm to patients. 相似文献
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Adrianna Douvris Khalid Zeid Swapnil Hiremath Sean M. Bagshaw Ron Wald William Beaubien-Souligny Jennifer Kong Claudio Ronco Edward G. Clark 《Intensive care medicine》2019,45(10):1333-1346
Hemodynamic instability related to renal replacement therapy (HIRRT) is a frequent complication of all renal replacement therapy (RRT) modalities commonly used in the intensive care unit. HIRRT is associated with increased mortality and may impair kidney recovery. Our current understanding of the physiologic basis for HIRRT comes primarily from studies of end-stage kidney disease patients on maintenance hemodialysis in whom HIRRT is referred to as ‘intradialytic hypotension’. Nonetheless, there are many studies that provide additional insights into the underlying mechanisms for HIRRT specifically in critically ill patients. In particular, recent evidence challenges the notion that HIRRT is almost entirely related to excessive ultrafiltration. Although excessive ultrafiltration is a key mechanism, multiple other RRT-related mechanisms may precipitate HIRRT and this could have implications for how HIRRT should be managed (e.g., the appropriate response might not always be to reduce ultrafiltration, particularly in the context of significant fluid overload). This review briefly summarizes the incidence and adverse effects of HIRRT and reviews what is currently known regarding the mechanisms underpinning it. This includes consideration of the evidence that exists for various RRT-related interventions to prevent or limit HIRRT. An enhanced understanding of the mechanisms that underlie HIRRT, beyond just excessive ultrafiltration, may lead to more effective RRT-related interventions to mitigate its occurrence and consequences. 相似文献
30.
Grigg AP; Roberts AW; Raunow H; Houghton S; Layton JE; Boyd AW; McGrath KM; Maher D 《Blood》1995,86(12):4437-4445
To define an optimal regimen for mobilizing and collecting peripheral blood progenitor cells (PBPC) for use in allogeneic transplantation, we evaluated the kinetics of mobilization by filgrastim (recombinant met- human granulocyte colony-stimulating factor [r-metHuG-CSF]) in normal volunteers. Filgrastim was injected subcutaneously for up to 10 days at a dose of 3 (n = 10), 5 (n = 5), or 10 micrograms/kg/d (n = 15). A subset of volunteers from each dose cohort underwent a 7L leukapheresis on study day 6 (after 5 days of filgrastim). Granulocyte-macrophage colony-forming cell (GM-CFC) numbers in the blood were maximal after 5 days of filgrastim; a broader peak was evident for CD34+ cells between days 4 and 6. The 95% confidence intervals (CI) for mean number of PBPC per milliliter of blood in the three dose cohorts overlapped on each study day. However, on the peak day, CD34+ cells were significantly higher in the 10 micrograms/kg/d cohort than in a pool of the 3 and 5 micrograms/kg/d cohorts. Mobilization was not significantly influenced by volunteer age or sex. Leukapheresis products obtained at the 10 micrograms/kg/d dose level contained a median GM-CFC number of 93 x 10(4)/kg (range, 50 x 10(4)/kg to 172 x 10(4)/kg). Collections from volunteers receiving lower doses of filgrastim contained a median GM- CFC number of 36 x 10(4)/kg (range, 5 x 10(4)/kg to 204 x 10(4)/kg). The measurement of CD34+ cells per milliliter of blood on the day of leukapheresis predicted the total yield of PBPC in the leukapheresis product (r = .87, P < .0001). Assuming a minimum GM-CFC requirement of 50 x 10(4)/kg (based on our experience with autologous PBPC transplantation), all seven leukapheresis products obtained at the 10 micrograms/kg/d dose level were potentially sufficient for allogeneic transplantation purposes. We conclude that in normal donors, filgrastim 10 micrograms/kg/d for 5 days with a single leukapheresis on the following day is a highly effective regimen for PBPC mobilization and collection. Further studies are required to determine whether PBPC collected with this regimen reliably produce rapid and sustained engraftment in allogeneic recipients. 相似文献