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排序方式: 共有6492条查询结果,搜索用时 15 毫秒
991.
Moshe Hersch Gabriel Izbicki David Dahan Gabriel S. Breuer Gideon Nesher Sharon Einav 《Journal of critical care》2012
Purpose
Budget restrictions have led to shortage of intensive care unit (ICU) beds in several countries. Consequently, ventilated patients are often kept on the wards. This study examined survival likelihood among patients ventilated on the wards and the predictive value of commonly used severity-of-illness scores.Methods
This study is a prospective observation and characterization of consecutive, mechanically ventilated patients in 3 internal medicine wards of a single hospital who were denied ICU admission. Outcome measures are as follows: 28-day mortality, survival to hospital discharge, and 3 months postdischarge.Results
Eighty-six patients were examined. The patients were 78.9 ± 8.9 years old; 53% were independent preadmission. Respiratory insufficiency due to infection was the main reason for mechanical ventilation (58%). Charlson and acute physiology scores (APS) averaged 4 ± 2.2 and 91.8 ± 26.7, respectively. Twenty-eight-day mortality was 71%, whereas in-hospital mortality was 74% and 3 months postdischarge mortality was 79%. Survivors were significantly younger than nonsurvivors (74.4 ± 8.5 years vs 80.4 ± 8.6 years, P < .01), were more likely to be ventilated for cardiac causes (41% vs 11%, P = .04), and had significantly higher initial mean blood pressure (79.4 mm Hg vs 58.2 mm Hg, P = .02) and blood albumin levels (29.8 g/L vs 25.7 g/L, P = .05). Death rate was 10 times more likely, with an APS greater than 90 on the day of intubation as compared with an APS less than 90.Conclusion
Mortality in patients ventilated on the ward was high, especially in the subgroup of patients with an APS score greater than 90. The early calculation of APS may assist in focusing therapeutic efforts on patients with better survival chances. 相似文献992.
Cho Y Kim H Turner ND Mann JC Wei J Taddeo SS Davidson LA Wang N Vannucci M Carroll RJ Chapkin RS Lupton JR 《The Journal of nutrition》2011,141(6):1029-1035
We have demonstrated that fish oil- and pectin-containing (FO/P) diets protect against colon cancer compared with corn oil and cellulose (CO/C) by upregulating apoptosis and suppressing proliferation. To elucidate the mechanisms whereby FO/P diets induce apoptosis and suppress proliferation during the tumorigenic process, we analyzed the temporal gene expression profiles from exfoliated rat colonocytes. Rats consumed diets containing FO/P or CO/C and were injected with azoxymethane (AOM; 2 times, 15 mg/kg body weight, subcutaneously). Feces collected at initiation (24 h after AOM injection) and at aberrant crypt foci (ACF) (7 wk postinjection) and tumor (28 wk postinjection) stages of colon cancer were used for poly (A)+ RNA extraction. Gene expression signatures were determined using Codelink arrays. Changes in phenotypes (ACF, apoptosis, proliferation, and tumor incidence) were measured to establish the regulatory controls contributing to the chemoprotective effects of FO/P. At initiation, FO/P downregulated the expression of 3 genes involved with cell adhesion and enhanced apoptosis compared with CO/C. At the ACF stage, the expression of genes involved in cell cycle regulation was modulated by FO/P and the zone of proliferation was reduced in FO/P rats compared with CO/C rats. FO/P also increased apoptosis and the expression of genes that promote apoptosis at the tumor endpoint compared with CO/C. We conclude that the effects of chemotherapeutic diets on epithelial cell gene expression can be monitored noninvasively throughout the tumorigenic process and that a FO/P diet is chemoprotective in part due to its ability to affect expression of genes involved in apoptosis and cell cycle regulation throughout all stages of tumorigenesis. 相似文献
993.
Aucouturier J Isacco L Thivel D Fellmann N Chardigny JM Duclos M Duché P 《Clinical nutrition (Edinburgh, Scotland)》2011,30(6):780-785
Background & aims
Exercise induces adaptations in fat metabolism favourable to the treatment of obesity. However, time interval between meal and exercise alters substrate bioavailability and oxidation during exercise. The aim of this study was therefore to investigate the effect of time interval between food intake and exercise on substrate oxidation rates in obese and lean children.Methods
The metabolic responses to exercise of nine obese children (10.3 ± 1.8 years; %body fat: 36.1 ± 6.1) and seven lean children (9.2 ± 1.6 years; %body fat: 22.2 ± 4.1) were compared 1 h (time interval 1, TI1) and 3 h (TI3) after a standardized breakfast.Results
Despite significantly lower plasma glucose and insulin concentrations and large effect size suggesting a higher plasma FFA availability (lean, 1.43, obese 0.98), fat oxidation was not significantly increased in TI3 compared to TI1 in both lean and obese children. Fat oxidation contributed marginally to energy expenditure during exercise (<20%) in both conditions and groups but was moderately increased during TI3 compared to TI1 in lean children (effect size: 0.54).Conclusions
The low contribution of fat oxidation to energy expenditure during exercise in obese and lean children fed 3 h before exercise questions the efficacy of moderate intensity exercise to favourably affect fat balance. 相似文献994.
Sanjit Kaur Bhogal MSc David McGillivray MD Jean Bourbeau MD MSc Laurie H. Plotnick MD Susan Joan Bartlett PhD Andrea Benedetti PhD Francine Monique Ducharme MD MSc 《Journal of evaluation in clinical practice》2011,17(1):160-167
Rationale The administration of oral corticosteroids within the first hour in the emergency department is associated with reduced hospitalization rates in children with moderate and severe asthma, yet less than half of patients benefit from this recommendation. To ensure patients receive recommended treatment, a clear understanding of what is causing suboptimal care management is needed. The assessment of barriers and solutions to optimal care is often done without a thorough examination of the factors associated with non‐adherence. Objective To evaluate whether knowledge of factors associated with delayed administration of systemic corticosteroids modifies the focus and prioritization of barriers and solutions identified by focus groups. Methods We conducted two parallel focus groups of emergency health care professionals – one group informed and the other non‐informed of key factors. Both groups received a presentation on the acute asthma guidelines, the evidence supporting its recommendations, and current practice. In addition, the informed group was provided with the factors associated and not associated with delayed administration. The groups were given 20 minutes to discuss barriers and solutions, with 5 minutes each for voting for the main barriers and solutions. Group difference in the misdirection of discussion was measured as time spent discussing barriers that were shown not to be associated with systemic corticosteroids. Prioritization of barriers and solutions was based on group endorsement. Results The non‐informed group spent more time discussing barriers not associated with delayed administration (15 vs. 2 minutes, P = 0.05). Although the non‐informed group proposed more solutions, most were to overcome barriers not associated with delayed administration. Of the main barriers and solutions identified by each group, only one barrier and solution were similar between the two groups: emergency department overcrowding and administrating corticosteroids at triage. Conclusion The awareness of objective factors of non‐adherence enabled a more directed discussion on relevant barriers and solutions, affecting prioritization of each. The administration of oral corticosteroids at triage appears to be the best solution to overcome delayed administration. 相似文献
995.
Nair H Brooks WA Katz M Roca A Berkley JA Madhi SA Simmerman JM Gordon A Sato M Howie S Krishnan A Ope M Lindblade KA Carosone-Link P Lucero M Ochieng W Kamimoto L Dueger E Bhat N Vong S Theodoratou E Chittaganpitch M Chimah O Balmaseda A Buchy P Harris E Evans V Katayose M Gaur B O'Callaghan-Gordo C Goswami D Arvelo W Venter M Briese T Tokarz R Widdowson MA Mounts AW Breiman RF Feikin DR Klugman KP Olsen SJ Gessner BD Wright PF Rudan I Broor S Simões EA Campbell H 《Lancet》2011,378(9807):1917-1930
996.
997.
Marcott SA Clark PU Padman L Klinkhammer GP Springer SR Liu Z Otto-Bliesner BL Carlson AE Ungerer A Padman J He F Cheng J Schmittner A 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(33):13415-13419
Episodic iceberg-discharge events from the Hudson Strait Ice Stream (HSIS) of the Laurentide Ice Sheet, referred to as Heinrich events, are commonly attributed to internal ice-sheet instabilities, but their systematic occurrence at the culmination of a large reduction in the Atlantic meridional overturning circulation (AMOC) indicates a climate control. We report Mg/Ca data on benthic foraminifera from an intermediate-depth site in the northwest Atlantic and results from a climate-model simulation that reveal basin-wide subsurface warming at the same time as large reductions in the AMOC, with temperature increasing by approximately 2 °C over a 1–2 kyr interval prior to a Heinrich event. In simulations with an ocean model coupled to a thermodynamically active ice shelf, the increase in subsurface temperature increases basal melt rate under an ice shelf fronting the HSIS by a factor of approximately 6. By analogy with recent observations in Antarctica, the resulting ice-shelf loss and attendant HSIS acceleration would produce a Heinrich event. 相似文献
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