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排序方式: 共有847条查询结果,搜索用时 32 毫秒
41.
Simon Desmeules Renée Lévesque Isabelle Jaussent Hélène Leray-Moragues Lofti Chalabi Bernard Canaud 《Nephrology, dialysis, transplantation》2004,19(5):1182-1189
BACKGROUND: No single measurement adequately defines protein-energy malnutrition. In the dialysis population, somatic protein mass, a useful marker of protein malnutrition, is estimated using the creatinine index (CI), lean body mass (LBM) or both, but the clinical usefulness of these indices remains uncertain. Moreover, calculating these indices requires formal creatinine kinetics or urine and dialysate collection. A simpler method to estimate the creatinine generation rate (G(Cr)) probably might widen its use. METHODS: We evaluated the usefulness of creatinine-based indices for predicting mortality in a cohort of 226 French haemodiafiltration patients using the Cox proportional hazards method. We also proposed simple yet precise formulas to calculate post-dialysis creatinine (Cr(post)) concentrations and derive creatinine generation rates (G(Cr)) from readily available measures. These formulas were developed using a large database containing more than 10 000 measured Cr(post) and G(Cr) values based on formal creatinine modelling. A single set of monthly values was used to evaluate the validity of the formulas. RESULTS: When adjusted for comorbidities, sex and Kt/V, CI and LBM/body weight (LBM/BW) were better predictors of 5 year all-cause mortality than urea-based indices [survival relative risk (RR) = 0.24, P<0.01 for CI<22 mg/kg/day; RR = 0.33, P<0.02 for LBM/BW<0.75]. When the cohort was divided according to gender, similar results were found in males, but not in females. The different formulas allowed adequate prediction of Cr(post) and G(Cr) and classification of patients with good accuracy (CI<22: sensitivity = 94%, specificity = 82%; LBW/BW<0.75: sensitivity = 89%, specificity = 90%). CONCLUSIONS: In a haemodiafiltration population, CI and LBM are excellent predictors of long-term survival. In anuric Caucasian haemodialysis patients, CI and LBM can be estimated from biochemical and anthropometric measurements without relying on formal modelling. 相似文献
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Francis BN Abassi Z Heyman S Winaver J Hoffman A 《Journal of cardiovascular pharmacology》2004,44(Z1):S362-S365
Endothelin-1 (ET-1) exerts its biological actions through two receptor subtypes: endothelin-A (ETA) receptor and endothelin-B (ETB) receptor. We demonstrated previously that ET-1 induces systemic and renal cortical vasoconstriction via ETA whereas ETB mediates medullary vasodilation. Congestive heart failure (CHF) is characterized by increased vascular resistance and impaired renal hemodynamic and excretory function. While the pathophysiological effects of ET-1 in CHF are well established, the status of ETA and ETB in the kidney is poorly characterized. The present study examined the immunostaining and localization of ETA and ETB in the renal cortex and medulla of rats with experimental CHF induced by aorto-caval fistula. Rats with CHF were further subdivided, based on their daily urinary sodium excretion, into rats with compensated (urinary sodium excretion > 1200 microEq/day) and decompensated CHF (urinary sodium excretion < 200 microEq/day). ETA is predominantly localized to the cortex mainly in the peritubular capillaries, and is upregulated in rats with compensated and decompensated CHF compared with sham controls. In contrast, ETB is preferentially expressed in the outer and inner medulla, mainly in the vasa recta, the thick ascending limb of Henle's loop and the collecting duct. While compensated CHF is associated with upregulation of ETB in the collecting duct and vasa recta, decompensated CHF is accompanied with enhanced ETB abundance in the vasa recta and remarkable downregulation of this receptor subtype in the collecting duct. The findings suggest that upregulation of ETA may lead to a decrease in cortical blood flow while upregulation of ETB in the vasa recta probably contributes to the preservation of medullary blood flow. Furthermore, downregulation of ETB in the collecting duct, only in rats with decompensated CHF, could contribute to sodium retention in that subgroup. 相似文献
44.
1. Changes in the activity of acetylcholinesterase (AChE) have been reported in diabetes mellitus that have been linked to certain brain defects. The erythrocyte membrane AChE is reported to be similar to AChE present in the brain. 2. Epicatechin, a member of a group of polyphenolic compounds collectively known as "catechins" that are present in tea and belong to the flavonoid family, has been reported to possess insulin-like activity. 3. In the present study, the in vitro effect of (-)epicatechin and/or insulin was tested on erythrocyte membrane AChE in normal and type 2 diabetic patients. The aim of the study was to test the efficacy of (-)epicatechin to mimic insulin in its effect on erythrocyte membrane AChE. 4. Acetylcholinesterase activity was significantly lower in type 2 diabetic patients than in normal controls and in vitro insulin treatment restored this activity to normal levels. Epicatechin (1 mmol/L) also caused an elevation in AChE activity in diabetic erythrocytes, an effect that was similar to the effect of insulin. 5. Epicatechin has a pronounced insulin-like effect on erythrocyte membrane-bound AChE in type 2 diabetic patients; however, the mechanism of action of epicatechin remains speculative. 相似文献
45.
Abdullah Faris Lian Khalid Mohammed Hashim Sara Yaghi Taif Magde Ward Bouresly Zaid Hamdoon Asmaa T. Uthman Hesham Marei Natheer Al-Rawi 《International dental journal》2022,72(3):278-287
BackgroundThe aim of this review was to evaluate the most used suture materials with regards to their inflammatory response, their bacterial adhesion, and their physical properties when used to close oral wounds.MethodsFour databases (PubMed, Scopus, Dentistry & Oral Sciences, and OVID) were searched to retrieve relevant studies from January 1, 2000, to January 31, 2020.ResultsOut of the 269 articles, only 13 studies were selected as they were relevant and met the systematic review's protocol. These studies showed that almost all suture materials studies (catgut, polyglycolic acid [PGA] sutures, nylon, expanded polytetrafluoroethylene, and silk sutures) caused bacterial adherence and tissue reaction. In nylon and chromic catgut, the number of bacteria accumulated was lowest. Silk and nylon were found to be more impacted than catgut and PGA in terms of physical characteristics such as tensile strength. PGA, on the other hand, was said to be the most susceptible to knot unwinding.ConclusionsFollowing an oral surgical operation, all sutures revealed varied degrees of irritation and microbial accumulation. Nonresorbable monofilament synthetic sutures, however, exhibited less tissue response and less microbial accumulation. 相似文献
46.
Nikhil P. Mankuzhy Muayad F. Almahariq Zaid A. Siddiqui Andrew B. Thompson Inga S. Grills Thomas M. Guerrero Kuei C. Lee Craig W. Stevens Thomas J. Quinn 《Clinical lung cancer》2021,22(1):e5-e17
BackgroundThe role for postoperative radiation therapy (PORT) for patients with non–small-cell lung cancer (NSCLC) with mediastinal lymph node (LN) involvement (pN2 disease) is controversial. We compared surgery alone with PORT among patients with pN2 NSCLC. We then performed subset analyses to better delineate patients that might benefit from PORT.Patients and MethodsWe conducted a propensity score (PS)-matched, inverse probability of treatment weighting (IPTW) Surveillance, Epidemiology, and End Results (SEER) analysis of patients with pN2 disease from 1989 to 2016 with surgery alone or PORT. Multiple imputation with chained equations was used for missing LN data.ResultsA total of 8631 patients were included in this analysis; 4579 underwent surgery alone, and 4052 underwent PORT. Following PS matching and IPTW, there was no difference in overall survival (OS) (hazard ratio [HR], 0.99; P = .76). However, PORT improved OS among a subset of patients with a LN positive to sampled ratio ≥ 50% (HR, 0.90; P = .01). Moreover, there was a trend towards improved OS among this subset, even with chemotherapy (HR, 0.91; P = .09).ConclusionPORT is not associated with an improvement or detriment in OS for all patients with pN2 NSCLC. However, patients with a positive to sampled LN ratio ≥ 50% may benefit, regardless of chemotherapy status. Nevertheless, PORT will remain the standard of care as we await the results of the ongoing LUNG ART trial. 相似文献
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In rabbits the blood glucose and consequently the aqueous humour glucose levels were increased under general anaesthesia by Ketanest-xylazine. Between 60 and 90 min of the general anaesthesia the average blood glucose levels were found to be three times and those of the aqueous humour twice the normal values. After more than 75 min of anaesthesia the glucose levels tended to be further elevated. 相似文献