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91.
92.
An apparently anomalous relationship between insulin and C-peptide concentrations in their initial response to intravenous glucose. 总被引:1,自引:0,他引:1
C Walton I F Godsland A J Proudler C V Felton V Wynn 《Metabolism: clinical and experimental》1992,41(11):1210-1214
Intravenous glucose tolerance tests (IVGTTs) with determination of plasma glucose, insulin, and C-peptide concentrations were performed in 136 men and 154 women. It was found that in 4% of men and 12% of women the plasma concentration of insulin exceeded that of C-peptide during the initial response to glucose. Subjects exhibiting this phenomenon had lower fasting and post-glucose C-peptide concentrations than those who did not; however, there were no statistically significant differences in glucose or insulin concentrations. The phenomenon was age-related, being absent from individuals aged 35 years and under, while in older age groups it appeared to be more prevalent in women than in men, suggesting an additional effect of menopause. However, in three follow-up IVGTTs performed in a subgroup of postmenopausal women over a period of 18 months, the phenomenon failed to recur in any of the individuals who first exhibited it, although it did occur in others. Our observations suggest the existence of an age-related but intermittent decrease in pancreatic insulin secretion, which does not lead to any significant change in plasma insulin concentrations, possibly as a result of reduced hepatic uptake of insulin. One consequence appears to be an excess of insulin over C-peptide during the early part of the IVGTT, which is probably related to the different distributional kinetics of the two peptides. 相似文献
93.
First myocardial infarction in patients under 60 years old: the role of exercise tests and symptoms in deciding whom to catheterise.
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OBJECTIVE--To determine the role of exercise tests and assessment of angina in the detection of potentially threatening disease in young patients with infarcts. DESIGN--Elective readmission of patients at a mean (SD) of 60 (30) days after acute myocardial infarction for assessment of angina, treadmill exercise tests, and cardiac catheterisation. SETTING--Cardiology department of a teaching hospital. PATIENTS--186 consecutive survivors, aged under 60 years and discharged from the coronary care unit after a first myocardial infarction. MAIN OUTCOME MEASURES--Coronary arteriography, presence of angina, result of exercise tests, and referral for revascularisation. RESULTS--31% of patients had either two vessel disease (with proximal left anterior descending involvement), three vessel disease, or left main stem disease. 49% of all patients had angina. Of the 173 patients who had an exercise test 34% had 1 mm and 24% had 2 mm of exercise induced ST depression. Thirty percent had no angina and a negative exercise test: after a mean (SD) follow up of 16 (4) months none of this symptom free sub-group had died, had experienced a further myocardial infarction, or had been referred for revascularisation. 79% of patients with either two vessel disease (with proximal left anterior descending involvement), three vessel disease, or left main stem disease had either angina or a 1 mm ST depression during the exercise test. CONCLUSION--Patients without cardiac pain after myocardial infarction and without ST changes during an exercise do not need arteriography. 相似文献
94.
Luke V. Rasmussen John J. Connolly Guilherme Del Fiol Robert R. Freimuth Douglas B. Pet Josh F. Peterson Brian H. Shirts Justin B. Starren Marc S. Williams Nephi Walton Casey Overby Taylor 《Applied clinical informatics》2021,12(2):383
Objectives The study aimed to understand potential barriers to the adoption of health information technology projects that are released as free and open source software (FOSS). Methods We conducted a survey of research consortia participants engaged in genomic medicine implementation to assess perceived institutional barriers to the adoption of three systems: ClinGen electronic health record (EHR) Toolkit, DocUBuild, and MyResults.org. The survey included eight barriers from the Consolidated Framework for Implementation Research (CFIR), with additional barriers identified from a qualitative analysis of open-ended responses. Results We analyzed responses from 24 research consortia participants from 18 institutions. In total, 14 categories of perceived barriers were evaluated, which were consistent with other observed barriers to FOSS adoption. The most frequent perceived barriers included lack of adaptability of the system, lack of institutional priority to implement, lack of trialability, lack of advantage of alternative systems, and complexity. Conclusion In addition to understanding potential barriers, we recommend some strategies to address them (where possible), including considerations for genomic medicine. Overall, FOSS developers need to ensure systems are easy to trial and implement and need to clearly articulate benefits of their systems, especially when alternatives exist. Institutional champions will remain a critical component to prioritizing genomic medicine projects. 相似文献
95.
96.
Evidence of endothelial dysfunction in angiographically normal coronary arteries of patients with coronary artery disease 总被引:12,自引:0,他引:12
Acetylcholine causes endothelium-dependent dilation of normal arteries in most animal species. The effect of acetylcholine on normal human coronary arteries is controversial. Pathologic studies and epicardial echocardiography have shown that diffuse atherosclerosis is often present despite angiographic evidence of discrete coronary artery disease (CAD). Therefore, we postulated that acetylcholine would cause vasoconstriction of coronary arteries that are angiographically normal in patients with CAD. Coronary artery diameter, measured by automated quantification of digitized cineangiograms, was determined before and after the intracoronary infusion of 0.2 mM acetylcholine at 0.8-1.6 ml/min. The diameter of stenotic or irregular segments of six atherosclerotic coronary arteries decreased from 1.80 +/- 0.42 mm before acetylcholine to 1.26 +/- 0.46 mm after acetylcholine (p = 0.0025). Acetylcholine had a significantly different effect on the diameter of two groups of coronary arteries that are angiographically normal. Acetylcholine caused a 0.16 +/- 0.09-mm increase in the diameter of 14 normal coronary arteries in patients without CAD, whereas it caused a 0.26 +/- 0.12-mm decrease in the diameter of 14 normal coronary arteries in patients with CAD (p less than 0.01). Thus, the normal response to intracoronary acetylcholine is vasodilation, suggesting that endothelium-derived relaxing factor is released from normal human coronary endothelium. The vasoconstrictive effect of acetylcholine in the angiographically normal coronary arteries of patients with CAD suggests the presence of a diffuse abnormality of endothelial function. 相似文献
97.
Johnson NA Walton DW Sachinwalla T Thompson CH Smith K Ruell PA Stannard SR George J 《Hepatology (Baltimore, Md.)》2008,47(5):1513-1523
Nonalcoholic fatty liver is frequently observed in obese individuals, yet the factors that predict its development and progression to liver disease are poorly understood. We proposed that proton magnetic resonance spectroscopy ((1)H-MRS) might allow noninvasive assessment of hepatic lipid composition. Lipid saturation (SI) and polyunsaturation (PUI) indices measured by (1)H-MRS were in agreement with those expected in oils of known composition. Hepatic triglyceride concentration (HTGC) and composition were then measured in healthy lean (LEAN) men, obese men with normal HTGC (OB), and obese men with hepatic steatosis (OB+HS). The effect of marked changes in dietary fat consumption on hepatic lipids were also compared in lean men after 67 hours of a normal mixed (NM) diet versus a low-carbohydrate, high-saturated-fat (LCHF) diet. SI was significantly higher in OB+HS (0.970 +/- 0.004) and OB (0.944 +/- 0.008) versus LEAN (0.818 +/- 0.025) (P < 0.01 for both). PUI was significantly lower in OB+HS (0.003 +/- 0.001) and OB (0.022 +/- 0.005) versus LEAN (0.120 +/- 0.021) (P < 0.01), and significantly lower in OB+HS versus OB (P < 0.05). LCHF diet did not alter HTGC, SI, or PUI (P > 0.05). The (1)H-MRS method provides for rapid, qualitative assessment of lipid composition. Application of this technique in the liver produces results that are consistent with biopsy-based approaches demonstrating that relative hepatic lipid saturation increases and polyunsaturation decreases with obesity. Obesity-related hepatic steatosis is characterized by further depletion of polyunsaturated hepatic lipids. CONCLUSION: This readily available and noninvasive approach should promote further study into interactions between hepatic and whole-body lipid metabolism and help to elucidate the pathogenesis of disorders characterized by lipid accumulation within the liver. 相似文献
98.
Anne Mandy Claire Walton Jon Michaelis 《Disability and rehabilitation. Assistive technology》2015,10(2):108-112
Aims: This pilot study measured activities of daily living performance in individuals/participants with hemiplegia propelling both a standard dual handrim Action 3 wheelchair and a standard Action 3 wheelchair with a Neater Uni-Wheelchair kit attachment. The kit consists of a steerable front. Research questions: Does the use of the NUW affect the performance quality of activities of daily living in individuals/participants with hemiplegia. Is there a difference in the motor and process skills during activities of daily living performance, and in the time taken to complete the activities. Methods: Four individuals/participants with hemiplegia were used in a cross over, repeated measures trial. Assessment of Motor and Process Skills of users undertaking making a bed and laying a table “Swedish style”, tasks were measured and time taken to complete each task were recorded. Results: Bed making completion time was quicker in the Neater Uni-wheelchair (p?0.03). Motor skills were significantly higher than the process ability skills (p?0.05). Conclusion: Activities of daily living tasks in the Neater Uni-wheelchair were completed more efficiently with no loss in quality of motor and process skills performance. This suggests that the Neater Uni-wheelchair is a viable alternative to current one arm drive provision.
- Implications for Rehabilitation
Inappropriate wheelchair provision can result in capacity limitation and poorer quality of ADL motor skill as well-lowered process performance skill.
AMPS can help to explain motor and process skill differences in complex activities.
99.
Diagnostic value of biparametric magnetic resonance imaging (MRI) as an adjunct to prostate‐specific antigen (PSA)‐based detection of prostate cancer in men without prior biopsies
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Soroush Rais‐Bahrami M. Minhaj Siddiqui Srinivas Vourganti Baris Turkbey Ardeshir R. Rastinehad Lambros Stamatakis Hong Truong Annerleim Walton‐Diaz Anthony N. Hoang Jeffrey W. Nix Maria J. Merino Bradford J. Wood Richard M. Simon Peter L. Choyke Peter A. Pinto 《BJU international》2015,115(3):381-388
100.
Shofiq Islam Muhiuddin AhmedGary M. Walton Timothy G. DinanGary R. Hoffman 《Journal of cranio-maxillo-facial surgery》2012,40(1):82-85