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81.
OBJECTIVES: To determine the variation in total daily energy expenditure (TDEE) and respiratory quotient (RQ) in mechanically ventilated children and examine the relation to daily and cumulative energy balance toward optimizing nutritional therapy. METHODS: Serial measurements of TDEE and RQ were performed in 18 patients (median age 16 months) with an indirect calorimeter during admission (total 69 TDEE measurements). Daily caloric intake was recorded, and after determination of the amount of carbohydrates and fat a RQ of these macronutrients (RQ(macr)) was obtained. Daily 24-h urine was analyzed for urinary nitrogen excretion. RESULTS: There was a great variability in the median serial TDEE between children (40-64 kcal/kg), while the variation within individual children was small; the mean intraindividual coefficient of variation (CV) in daily measurements of TDEE was less than 10% in 15 of the 18 children (83%). On the last day of measurement 8 children with a positive cumulative energy balance (+98 kcal/kg) had a significantly higher RQ than 10 with a negative cumulative energy balance (-24 kcal/kg, 0.89 vs. 0.84). From the difference between RQ and RQ(macr) the optimal caloric intake was determined as 1.4x TDEE, divided into 60% carbohydrates and 40% fat. From the median nitrogen excretion of 33 samples (300 mg/kg per day, range 60-708) optimal daily protein intake was calculated as 1.9 g/kg (range 0.4-4.4). CONCLUSIONS: For most children a single measurement of TDEE gave a good insight in the daily energy needs. RQ is strongly affected by the ratio energy intake/TDEE and by the cumulative energy balance. Optimal caloric intake was found to be 1.4x TDEE with a daily protein intake of 1.9 g/kg. 相似文献
82.
Benjamin J Cowling Lincoln LH Lau Peng Wu Helen WC Wong Vicky J Fang Steven Riley Hiroshi Nishiura 《BMC infectious diseases》2010,10(1):82
Background
After the WHO issued the global alert for 2009 pandemic influenza A (H1N1), many national health agencies began to screen travelers on entry in airports, ports and border crossings to try to delay local transmission. 相似文献83.
Zhang C Kenny JR Le H Deese A Ford KA Lightning LK Fan PW Driscoll JP Halladay JS Hop CE Khojasteh SC 《Chemical research in toxicology》2011,24(10):1668-1677
The objective of the present study was to investigate the influence of halogen position on the formation of reactive metabolites from dihalogenated anilines. Herein we report on a proposed mechanism for dehalogenation and glutathione (GSH) conjugation of a series of ortho-, meta-, and para-dihalogenated anilines observed in human liver microsomes. Of particular interest were conjugates formed in which one of the halogens on the aniline was replaced by GSH. We present evidence that a (4-iminocyclohexa-2,5-dienylidene)halogenium reactive intermediate (QX) was formed after oxidation, followed by ipso addition of GSH at the imine moiety. The ipso GSH thiol attacks at the ortho-carbon and eventually leads to a loss of a halogen and GSH replacement. The initial step of GSH addition at the ipso position is also supported by density functional theory, which suggests that the ipso carbon of the chloro, bromo, and iodo (but not fluoro) containing 2-fluoro-4-haloanilines is the most positive carbon and that these molecules have the favorable highest occupied molecular orbital of the aniline and the lowest unoccupied orbital from GSH. The para-substituted halogen (chloro, bromo, or iodo but not fluoro) played a pivotal role in the formation of the QX, which required a delocalization of the positive charge on the para-halogen after oxidation. This mechanism was supported by structure-metabolism relationship analysis of a series of dihalogenated and monohalogenated aniline analogues. 相似文献
84.
Increased levels of circulating endothelial progenitor cells and circulating endothelial nitric oxide synthase in patients with gliomas 总被引:2,自引:0,他引:2
OBJECTIVE: Gliomas are among the highest vascularized tumors. We hypothesized that patients with gliomas have increased levels of circulating endothelial progenitor cells (EPCs) and circulating endothelial nitric oxide synthase (eNOS). METHODS: The fraction of EPCs was quantified by fluorescence-activated cell sorter analysis using anti-CD34, -CD133 and -KDR (kinase insert domain receptor) monoclonal antibodies in unselected peripheral blood samples of 32 patients with gliomas. Control groups included 47 patients with other central nervous system tumors or diseases, 10 patients with recent ischemic strokes, and 19 healthy blood donors. The circulating eNOS concentration of plasma was measured by a colorimetric assay in the same samples. In addition, CD34(+)CD105(+) KDR(+) and CD34(+)CD146(+)KDR(-) cell fractions were measured. RESULTS: The percentage of CD34(+)CD133(+)KDR(+) EPCs in the blood of glioma patients is significantly greater than that in the blood of patients with other central nervous system tumors or diseases (p = 0.003), stroke patients (p = 0.005), or healthy donors (p = 0.013). The plasma eNOS concentration is also significantly greater in glioma patients compared with each of the control groups (p < 0.001 for all groupwise comparisons). No significant differences in the levels of the EPCs or eNOS between any of the control groups were demonstrated. In the glioma patients, the level of eNOS correlated with the fraction of CD34(+)CD105(+)KDR(+) cells (r = 0.748; p = 0.008). INTERPRETATION: The data are suggestive of increased mobilization of EPCs contributing to neoplastic vasculogenesis in glioma. The increased levels of EPCs and eNOS in the peripheral blood of glioma patients trigger further investigations as to their value as independent parameters for use in clinical practice. 相似文献
85.
An IGF-I gene polymorphism modifies the risk of developing persistent microalbuminuria in type 1 diabetes 总被引:1,自引:0,他引:1
Hovind P Lamberts S Hop W Deinum J Tarnow L Parving HH Janssen JA 《European journal of endocrinology / European Federation of Endocrine Societies》2007,156(1):83-90
OBJECTIVE: Derangements of the GH-IGF-I axis have been associated with microalbuminuria (MA) in type 1 diabetes. The aim of this study was to investigate whether an IGF-I gene promoter polymorphism influenced the development of persistent MA in type 1 diabetes. DESIGN: A prospective follow-up study of a cohort of 277 patients with newly diagnosed type 1 diabetes consecutively enrolled between September 1979 and August 1984. METHODS: Urinary albumin excretion rate over 24 h was measured in each patient at least once a year. Persistent MA was defined as a urinary albumin excretion rate between 30 and 300 mg/24 h. RESULTS: During a median follow-up of 18.0 years (range 1.0-21.5), 79 of 277 patients developed persistent MA. IGF-I gene genotype was available for 216 subjects; in 73% of the subjects, the wild-type genotype of this IGF-I gene polymorphism was present, while 27% had the variant type. At baseline, there were no differences in IGF-I levels and HbA(1c) values between subjects with the wild type and subjects with variant type. By Kaplan-Meier analysis, subjects with the variant type of this polymorphism had during follow-up a higher risk of development of MA compared subjects with the wild type (P = 0.03). CONCLUSIONS: Subjects with the variant type of an IGF-I gene polymorphism had a significantly increased risk of developing MA. This risk was not mediated through changes in circulating IGF-I levels. Our study suggests that in type 1 diabetes, this IGF-I gene polymorphism is a risk factor of MA. 相似文献
86.
87.
van den Bos IC Hussain SM Dwarkasing RS Hop WC Zondervan PE de Man RA IJzermans JN Walker CW Krestin GP 《Journal of magnetic resonance imaging : JMRI》2007,26(6):1548-1555
PURPOSE: To assess the relationship between lesion size and MR imaging findings of pathologically-proven hepatocellular carcinoma (HCC). MATERIALS AND METHODS: In a retrospective, single-center study, 37 consecutive patients were identified between 1999 and 2005 that underwent preoperative MRI and surgical resection of HCC. A total of 47 lesions (mean size = 6.85 cm, range = 1-25 cm) were assessed for signal intensity (SI), enhancement patterns, and secondary morphologic features. Interobserver rating, percentage enhancement, and contrast-to-noise-ratio (CNR) were determined. Lesions were assessed for combinations of typical MRI features. Regression analysis was used to assess relations between MRI findings and tumor size. RESULTS: On fat-suppressed T2-weighted (T2w) fast-spin-echo, smaller lesions had lower SI compared to larger lesions (P < 0.05). In the arterial phase, smaller lesions showed significantly higher percentage enhancement compared to larger lesions (P < 0.05). In the delayed phase, smaller lesions showed less pronounced washout (P < 0.05). Heterogeneity of the lesions, including fatty infiltration, internal nodules, or mosaic pattern, was observed significantly more frequently in larger lesions (P < 0.001). The classic combination of high T2w signal, strong arterial enhancement, and delayed phase washout was present in 23 of 44 lesions (52%). CONCLUSION: Smaller HCC often showed lower SI on T2w, more intense arterial enhancement, and less pronounced delayed washout compared to larger HCC. 相似文献
88.
Long-term survival and metastatic pattern of pancreatic and periampullary cancer after adjuvant chemoradiation or observation: long-term results of EORTC trial 40891
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Smeenk HG van Eijck CH Hop WC Erdmann J Tran KC Debois M van Cutsem E van Dekken H Klinkenbijl JH Jeekel J 《Annals of surgery》2007,246(5):734-740
89.
Bonjer HJ Hop WC Nelson H Sargent DJ Lacy AM Castells A Guillou PJ Thorpe H Brown J Delgado S Kuhrij E Haglind E Påhlman L;Transatlantic Laparoscopically Assisted vs Open Colectomy Trials Study Group 《Archives of surgery (Chicago, Ill. : 1960)》2007,142(3):298-303
OBJECTIVE: To perform a meta-analysis of trials randomizing patients with colon cancer to laparoscopically assisted or open colectomy to enhance the power in determining whether laparoscopic colectomy for cancer is oncologically safe. DATA SOURCES: The databases of the Barcelona, Clinical Outcomes of Surgical Therapy (COST), Colon Cancer Laparoscopic or Open Resection (COLOR), and Conventional vs Laparoscopic-Assisted Surgery in Patients With Colorectal Cancer (CLASICC) trials were the data sources for the study. STUDY SELECTION: Patients who had at least 3 years of complete follow-up data were selected. DATA EXTRACTION: Patients who had undergone curative surgery before March 1, 2000, were studied. Three-year disease-free survival and overall survival were the primary outcomes of this analysis. DATA SYNTHESIS: Of 1765 patients, 229 were excluded, leaving 796 patients in the laparoscopically assisted arm and 740 patients in the open arm for analysis. Three-year disease-free survival rates in the laparoscopically assisted and open arms were 75.8% and 75.3%, respectively (95% confidence interval [CI] of the difference, -5% to 4%). The associated common hazard ratio (laparoscopically assisted vs open surgery with adjustment for sex, age, and stage) was 0.99 (95% CI, 0.80-1.22; P = .92). The 3-year overall survival rate after laparoscopic surgery was 82.2% and after open surgery was 83.5% (95% CI of the difference, -3% to 5%). The associated hazard ratio was 1.07 (95% CI, 0.83-1.37; P = .61). Disease-free and overall survival rates for stages I, II, and III evaluated separately did not differ between the 2 treatments. CONCLUSION: Laparoscopically assisted colectomy for cancer is oncologically safe. 相似文献