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排序方式: 共有673条查询结果,搜索用时 15 毫秒
61.
Perry CG Palmer T Cleland SJ Morton IJ Salt IP Petrie JR Gould GW Connell JM 《Clinical science (London, England : 1979)》2003,105(2):187-194
We have previously reported that modest dietary sodium restriction, as advocated in management guidelines for diabetes, may reduce insulin sensitivity. It has since been suggested that this effect may be mediated via cross-talk between insulin and angiotensin II (AII)-stimulated intracellular second messengers. In order to assess the effect of 5 days of modest sodium restriction (to <80 mmol/day target sodium intake) on insulin sensitivity, 15 healthy males underwent a double-blind, placebo-controlled, randomized, cross-over euglycaemic hyperinsulinaemic clamp study. One phase was supplemented with sodium tablets and the other with matched placebo. Insulin sensitivity (M) was reduced during dietary sodium restriction [median M value, 10.2 mg/kg per min (interquartile range 9.50-13.85) versus 12.8 mg/kg per min (interquartile range 9.60-14.30), P <0.05]. To elucidate potential mechanisms that may explain this observation, we investigated the effect of AII on insulin action in isolated adipocytes obtained from healthy females. No effect of AII on insulin-mediated glucose transport or suppression of lipolysis was observed. In conclusion, despite the observation that dietary sodium restriction was associated with a median 15% reduction in insulin sensitivity, we found no evidence of a direct effect of AII on insulin action in human adipocytes. 相似文献
62.
Ömer Salt Polat Durukan S. Ozkan R. Saraymen A. Sen M.A. Yurci 《The American journal of emergency medicine》2017,35(10):1440-1443
Introduction
Gastrointestinal bleeding is a significant cause of morbidity and mortality worldwide. In addition, it constitutes an important part of health expenditures.In this study, we aimed to determine whether there is a relationship between plasma copeptin levels and the etiology, location and severity of gastrointestinal bleeding.Materials and methods
This study was performed prospectively in 104 consecutive patients who were admitted to an emergency department with complaints of bloody vomiting or bloody or black stool. To evaluate the level of biochemical parameters such as Full Blood Count (FBC), serum biochemistry, bleeding parameters and copeptin, blood samples were obtained at admission. For the copeptin levels, 2 more blood samples were obtained at the 12th and 24th hours after admission.The values obtained were compared using statistical methods.Results
In terms of the etiology of bleeding, the copeptin levels in the patients with peptic ulcer were higher than the levels in patients with other gastrointestinal bleeding. However, the difference was not statistically significant.There were no significant differences among all groups' 0th, 12th and 24th hour levels of copeptin.Discussion
We conclude that copeptin cannot be effectively used as a biochemical parameter in an emergency department to determine the etiology and location of gastrointestinal bleeding. It can, however, be used to make decisions on endoscopy and the hospitalization of patients with suspected gastrointestinal bleeding. 相似文献63.
Williams TN; Maitland K; Phelps L; Bennett S; Peto TE; Viji J; Timothy R; Clegg JB; Weatherall DJ; Bowden DK 《QJM : monthly journal of the Association of Physicians》1997,90(12):751-757
We studied the aetiology of malnutrition in a cohort of 1511 children <
10 years old in Espiritu Santo, Vanuatu. Malnutrition was categorized using
standard anthropometric criteria as: underweight [weight-for-age (WA) Z
score < -2], wasting [weight-for-height (WH) Z < -2], or stunting
[height-for-age (HA) Z < -2]. On multiple logistic regression analysis,
the only factors significantly associated with wasting were age < 5
years [OR (95% CI) 1.8 (1.2-2.9), p = 0.01] and having suffered one or more
episodes of clinical P. vivax malaria in the 6 months preceding nutritional
assessment [OR 2.4 (1.3-4.4), p = 0.006]. The incidence of P. vivax
infection was significantly higher during the 6 months preceding assessment
in underweight vs. non-underweight children [incidence rate ratio (IRR) 2.6
(1.5-4.4), p < or = 0.0001). These groups had similar incidences of
clinical P. falciparum infection during the same period [IRR 1.1 (0.57-2.1)
p = 0.8] and of either species during the 6 months following assessment
[IRR P. vivax 1.3 (0.9- 2.0) p = 0.2; IRR P. falciparum 1.3 (0.9-1.9) p =
0.2]. In these children, P. vivax malaria was a major predictor of acute
malnutrition; P. falciparum was not. Wasting neither predisposed to nor
protected against malaria of either species. Although P. vivax malaria is
generally regarded as benign, it may produce considerable global mortality
through malnutrition.
相似文献
64.
Walker AS; Peto TE; Babiker AG; Darbyshire JH 《QJM : monthly journal of the Association of Physicians》1998,91(6):423-438
The Concorde trial compared immediate (Imm) with deferred (Def) AZT
monotherapy in asymptomatic HIV-positive participants. Haematological and
immunological markers and weight were measured throughout, and correlated
with clinical endpoints. Markers associated with disease progression (CD4
lymphocyte count and percentage, platelets, p24 antigen and beta 2
microglobulin favoured Imm: those associated with toxicity (haemoglobin,
neutrophils and white cell count) favoured Def. CD8 and total lymphocyte
count did not differ significantly between groups. In multivariate
analysis, the combination of baseline CD4, p24 antigen and beta 2m was the
best baseline predictor of disease. Including change in CD4 and beta 2m at
12 weeks, or changes over follow- up in these markers significantly
improved the fit. Markers were also incorporated into the definition of
'clinical' endpoints. Hazard ratio estimates from end-points that included
CD4 < 50 and CD4 < 25 were closest to those for AIDS or death alone,
but added very few extra events. Use of other landmark CD4 counts (100 or
greater) or relative decreases in counts (25% or more) increased the number
of events, but overestimated the effect of immediate AZT. Although AZT had
a beneficial effect on the surrogate markers of efficacy evaluated, these
changes did not predict clinical outcome, nor could the markers be usefully
incorporated into an endpoint definition.
相似文献
65.
T. T. KELLER C. NAGEL H. TE VELTHUIS† V. E. A. GERDES N. J. WAREHAM‡ S. A. BINGHAM§ R. LUBEN¶ C. E. HACK P. H. REITSMA†† M. LEVI K. T. KHAW¶ S. M. BOEKHOLDT‡‡ 《Journal of thrombosis and haemostasis》2006,4(11):2391-2396
INTRODUCTION: Tissue factor (TF) has been implicated in coronary artery disease (CAD). High levels of circulating TF are found in patients with acute atherothrombotic events. Whether high serum TF levels predict risk of future CAD independent of known risk factors remains unknown. METHODS: We conducted a prospective case-control study nested in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk population study. Cases (n=1037) were apparently healthy men and women, aged 45-79 years, who developed fatal or non-fatal CAD during follow-up. Controls (n=2005) were matched by age, sex, and enrolment time. Serum TF levels were measured using high-affinity antibodies. RESULTS: In men, median TF levels were not significant higher in cases than in controls (59.0 pg mL-1, range: 16.7-370.4 vs. 54.9 pg mL-1, range: 16.2-452.4). In women, median TF levels were not significant higher in controls than in cases (73.4 pg mL-1, range: 16.7-492.3 vs. 50.5 pg mL-1, range: 16.5-376.7). The incidence of smoking was about double in the lowest compared with the highest TF quartile. Correcting for sex, age, body mass index, smoking, diabetes, systolic blood pressure, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol and C-reactive protein levels, the risk of future CAD was 1.05 (95% CI: 0.81-1.36) for people in the highest TF quartile, compared with those in the lowest (P-value for linearity=0.8). CONCLUSION: High levels of serum TF were not independently associated with an increased risk of future CAD in apparently healthy individuals. 相似文献
66.
Baxter IR Vitek O Lahner B Muthukumar B Borghi M Morrissey J Guerinot ML Salt DE 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(33):12081-12086
The contention that quantitative profiles of biomolecules contain information about the physiological state of the organism has motivated a variety of high-throughput molecular profiling experiments. However, unbiased discovery and validation of biomolecular signatures from these experiments remains a challenge. Here we show that the Arabidopsis thaliana (Arabidopsis) leaf ionome, or elemental composition, contains such signatures, and we establish statistical models that connect these multivariable signatures to defined physiological responses, such as iron (Fe) and phosphorus (P) homeostasis. Iron is essential for plant growth and development, but potentially toxic at elevated levels. Because of this, shoot Fe concentrations are tightly regulated and show little variation over a range of Fe concentrations in the environment, making them a poor probe of a plant's Fe status. By evaluating the shoot ionome in plants grown under different Fe nutritional conditions, we have established a multivariable ionomic signature for the Fe response status of Arabidopsis. This signature has been validated against known Fe-response proteins and allows the high-throughput detection of the Fe status of plants with a false negative/positive rate of 18%/16%. A “metascreen” of previously collected ionomic data from 880 Arabidopsis mutants and natural accessions for this Fe response signature successfully identified the known Fe mutants frd1 and frd3. A similar approach has also been taken to identify and use a shoot ionomic signature associated with P homeostasis. This study establishes that multivariable ionomic signatures of physiological states associated with mineral nutrient homeostasis do exist in Arabidopsis and are in principle robust enough to detect specific physiological responses to environmental or genetic perturbations. 相似文献
67.
The biocompatibility of nine different white cell filters was examined by analysis of complement activation in plasma specimens obtained from blood components before and after filtration. Filters for both red cell (RBC) concentrates and platelet concentrates (PCs) were tested. It was found in all of the filters tested that the postfiltration levels of complement activation products were not higher than the prefiltration levels in RBC concentrates and PCs. One exception was the filtration of multiple PCs with Imugard IG-500, in which case a rise in C3 activation products was seen. Moreover, there was a significant rise in C3 activation products, but not the terminal complement complex, when plasma was filtered through Imugard E, which contrasted with results with the other filters. High initial and storage time-dependent levels, especially of C3 activation products, were observed in the PCs, probably due to their processing at room temperature. It can be concluded that the majority of the filters tested do not activate complement. 相似文献
68.
Platelet concentrates stored for 5 days in a reduced volume of plasma maintain hemostatic function and viability 总被引:2,自引:0,他引:2
BACKGROUND: Platelet concentrates prepared from whole blood are generally suspended in a standard volume of 50 to 60 mL of plasma and can be stored thus at 20 to 24 degrees C for up to 5 days. In vitro studies suggested that this plasma volume could be reduced to 30 to 35 mL without impairing platelet function. STUDY DESIGN AND METHODS: This study evaluated whether platelets stored for 5 days in a reduced volume (30-35 mL) of plasma maintained their in vivo viability, hemostatic function, and recovery in recipients. Paired autologous platelet survival studies were done in 20 adult volunteers to assess platelet viability. A rabbit ear bleeding-time model was used to compare the hemostatic effectiveness of human platelet concentrates stored for 5 days in the standard or reduced volume of plasma. Platelet recovery was compared in thrombocytopenic hospital patients. RESULTS: Paired platelet survival studies indicated no significant difference between the values in platelet concentrates stored for 5 days in the reduced volume of plasma and the values in those stored in the standard volume. In the animal model, there was no significant difference in the bleeding times achieved by either set of platelet concentrates. The platelet count increments in thrombocytopenic patients were measured. The platelet count increments in patients who received reduced-volume platelet concentrates were as good as the increments achieved in patients given standard-volume concentrates. CONCLUSION: The in vivo viability, recovery, and hemostatic function of platelets collected in polyvinylchloride plastic containers and stored in 30 to 35 mL of plasma for 5 days are maintained as well as those of platelets stored in 50 to 60 mL of plasma. 相似文献
69.
70.
Pazarli P Yarkin T Karakurt Z Yetis Duman D Saltürk C Celik B Baran R 《Tüberküloz ve toraks》2007,55(4):323-328
To evaluate DeltaHb (daily changes of hemoglobin concentrations) in nonbleeding critically ill patients, and to investigate its relation with diagnostic blood loss (DBL) and fluid balance (FB). Hospital records of 34 nonseptic patients who stayed in respiratory intensive care unit (RICU) at least 72 hours with no evidence of acute bleeding, renal failure and bleeding diathesis, were evaluated retrospectively. Demographics, clinical features, acute physiology assessment and chronic health evaluation (APACHE) II scores, daily Hb levels, DBL and FB were recorded. Correlation statistics was performed between DeltaHb and DBL and FB. We compared the patients with DeltaHb > or =0.5 g/dL/day (group A) and the patients with DeltaHb < 0.5 g/dL/day (group B) in the first three days. The mean age was 55 +/- 14, Hb level was 13.2 +/- 1.7 g/dL at admission and 12.6 +/- 2.3 g/dL at discharge from RICU. DBL was 25.2 +/- 7.4 mL/d, and FB was 251 +/- 1783 mL/d for the first day in intensive care unit. DBL was lesser in subsequent days than in the first day but it wasn't significant. DeltaHb was -0.54 +/- 1.5 g/dL for the first three days, while it was -0.23 +/- 1.5 g/dL for subsequent four days (p= 0.9). DeltaHb in the first three days has no correlation with DBL and FB. Age, sex, APACHE II score, clinical features, DBL and FB were not differed between Group A and Group B. CONCLUSION: No relation was found between DeltaHb and DBL, and also FB; but studies like this are important to indicate that Hb concentrations may decrease in critically ill patients without any reason such as bleeding. 相似文献