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81.
T. S. Hermann C. H. Dall S. B. Christensen J. P. Goetze E. Prescott F. Gustafsson 《American journal of transplantation》2011,11(3):536-541
Coronary allograft vasculopathy is a well‐known long‐term complication after cardiac transplantation. Endothelial dysfunction is involved and may be prevented by aerobic exercise. The purpose of this study was to examine whether high intensity aerobic exercise improves peak oxygen uptake (VO2 peak) and endothelial function in heart transplant (HT) recipients. Twenty‐seven long‐term HT recipients were randomized to either 8‐weeks high intensity aerobic exercise or no training. Flow mediated dilation of the brachial artery (FMD) was measured by ultrasound and VO2 peak by the analysis of expired air. Blood pressure and biomarkers were measured before and after 8 weeks. VO2 peak increased significantly in the exercise group (VO2 peak 23.9 ± 1.79 to 28.3 ± 1.63 mL/kg/min compared to controls (VO2 peak 24.6 ± 1.38 to 23.4 ± 1.58, p < 0.001 exercise vs. control).FMD increased in the exercise group compared to controls (8.3 ± 1.1% to 11.4 ± 1.2% vs. 5.6 ± 1.0% to 5.3 ± 1.7%, p = 0.024). No increase in nitroglycerin‐induced vasodilation was observed. Systolic blood pressure fell in the exercise group (142 ±4.2 mmHg to127 ± 3.4 mmHg, p = 0.01) and was unchanged in controls (141 ± 4.2 mmHg to 142 ±6.4 mmHg, NS). High intensity aerobic exercise reduces systolic blood pressure and improves endothelial function in HT recipients. 相似文献
82.
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography. 相似文献
83.
Enhancement of chemotactic factor-stimulated neutrophil oxidative metabolism by leukotriene B4 总被引:4,自引:0,他引:4
Leukotriene B4 (LTB4) is a potent primary stimulator of neutrophil chemotaxis, aggregation, and degranulation and induces superoxide production at higher concentrations. In order to determine whether LTB4 modulates neutrophil responses to oxidative stimuli, human neutrophils (PMNs) were incubated with LTB4 prior to stimulation with f-Met-Leu-Phe (fMLP, 10(-7) mol/L), opsonized zymosan (OZ, 250 micrograms/mL), or phorbol myristate acetate (PMA, 32 nmol/L). Superoxide (O2-) production by stimulated PMNs was assessed by the superoxide dismutase-inhibitable reduction of cytochrome c. LTB4 alone did not stimulate O2- production in concentrations below 10(-7) mol/L and had no effect on the O2- assay. In the concentration range of 10(-12) to 10(-8) mol/L, LTB4 did not alter O2- release induced by OZ or PMA. In contrast, LTB4-treated cells demonstrated enhanced O2- production following exposure to fMLP, and in the presence of 10 nmol/LLTB4, generated 180% +/- 41% of O-2 quantities produced by control cells (n = 23). Enhancement was LTB4 dose-dependent, was maximal in the range of 1 to 10 nmol/L LTB4, was not reversed by removal of the lipid from the medium prior to fMLP stimulation, and was not dependent on the presence of Ca++ or Mg++ in the suspending medium. Chemiluminescence of fMLP-stimulated neutrophils was increased to 323% of controls in neutrophils preincubated with 10 nmol/L LTB4. Unlike augmentation of oxidative responses to fMLP seen with other degranulating stimuli, enhancement by LTB4 was not correlated with an increase in 3H-fMLP receptor binding. These results indicate that, in addition to its primary effects on neutrophil function, LTB4 modulates PMN oxidative responses to the chemotactic peptide and, thus, may amplify the release of oxygen metabolites at inflammatory foci. 相似文献
84.
DK Bilku AR Dennison TC Hall MS Metcalfe G Garcea 《Annals of the Royal College of Surgeons of England》2014,96(1):15-22
INTRODUCTION
Surgical stress in the presence of fasting worsens the catabolic state, causes insulin resistance and may delay recovery. Carbohydrate rich drinks given preoperatively may ameliorate these deleterious effects. A systematic review was undertaken to analyse the effect of preoperative carbohydrate loading on insulin resistance, gastric emptying, gastric acidity, patient wellbeing, immunity and nutrition following surgery.METHODS
All studies identified through PubMed until September 2011 were included. References were cross-checked to ensure capture of cited pertinent articles.RESULTS
Overall, 17 randomised controlled trials with a total of 1,445 patients who met the inclusion criteria were identified. Preoperative carbohydrate drinks significantly improved insulin resistance and indices of patient comfort following surgery, especially hunger, thirst, malaise, anxiety and nausea. No definite conclusions could be made regarding preservation of muscle mass. Following ingestion of carbohydrate drinks, no adverse events such as apparent or proven aspiration during or after surgery were reported.CONCLUSIONS
Administration of oral carbohydrate drinks before surgery is probably safe and may have a positive influence on a wide range of perioperative markers of clinical outcome. Further studies are required to determine its cost effectiveness. 相似文献85.
Jorg R. Oddens Richard J. Sylvester Maurizio A. Brausi Wim J. Kirkels Cees van de Beek George van Andel Theo M. de Reijke Stephen Prescott J. Alfred Witjes Willem Oosterlinck 《European urology》2014
Background
Although maintenance bacillus Calmette-Guérin (BCG) is the recommended treatment in high-risk non–muscle-invasive bladder cancer (NMIBC), its efficacy in older patients is controversial.Objective
To determine the effect of age on prognosis and treatment outcome in patients with stage Ta T1 NMIBC treated with maintenance BCG.Design, setting, and participants
A total of 957 patients with intermediate- or high-risk Ta T1 (without carcinoma in situ) NMIBC were randomized in European Organization for Research and Treatment of Cancer (EORTC) trial 30911 comparing six weekly instillations of epirubicin, BCG, and BCG plus isoniazid followed by three weekly maintenance instillations over 3 yr.Outcome measurements and statistical analysis
Cox multivariate proportional hazards regression models were used to assess the relative importance of age for recurrence, progression, overall survival, and NMIBC-specific survival with adjustment for EORTC risk scores.Results and limitations
Overall, 822 eligible patients were included: 546 patients in the BCG with or without INH arms and 276 in the epirubicin arm. In patients treated with BCG with or without INH, 34.1% were >70 yr of age and 3.7% were >80 yr. With a median follow-up of 9.2 yr, patients >70 yr had a shorter time to progression (p = 0.028), overall survival (p < 0.001), and NMIBC-specific survival (p = 0.049) after adjustment for EORTC risk scores in the multivariate analysis. The time to recurrence was similar compared with the younger patients. BCG was more effective than epirubicin for all four end points considered, and there was no evidence that BCG was any less effective compared with epirubicin in patients >70 yr.Conclusions
In intermediate- and high-risk Ta T1 urothelial bladder cancer patients treated with BCG, patients >70 yr of age have a worse long-term prognosis; however, BCG is more effective than epirubicin independent of patient age.Patient summary
Intravesical bacillus Calmette-Guérin for non–muscle-invasive bladder cancer is less effective in patients >70 yr of age, but it is still more effective than epirubicin.Trial registration
This study was registered with the US National Cancer Institute clinical trials database (protocol ID: EORTC 30911; http://www.cancer.gov/clinicaltrials/search/view?cdrid=77075&version=HealthProfessional&protocolsearchid=12442243#StudyIdInfo_CDR0000077075). 相似文献86.
N. H. Rod M. Grønbæk P. Schnohr E. Prescott T. S. Kristensen 《Journal of internal medicine》2009,266(5):467-475
Objective. The aim of this study was to evaluate the long‐term effects of stress on changes in health behaviour and cardiac risk profile in men and women. Design. A prospective cohort study. Setting. The Copenhagen City Heart Study, Denmark. Subjects. The analyses were based on 7066 women and men from the second (1981–1983) and third (1991–1993) wave of the Copenhagen City Heart Study. All participants were asked questions on stress and health behaviour and they had their weight, height, blood pressure and level of blood lipids measured by trained personnel. Main outcome measures. Changes in health behaviour (smoking, physical activity, alcohol consumption, overweight) and cardiac risk profile (cholesterol, HDL cholesterol, blood pressure, diabetes). Results. Individuals with high levels of stress compared to those with low levels of stress were less likely to quit smoking (OR = 0.58; 95% CI: 0.41–0.83), more likely to become physically inactive (1.90; 1.41–2.55), less likely to stop drinking above the sensible drinking limits (0.43; 0.24–0.79), and stressed women were more likely to become overweight (1.55; 1.12–2.15) during follow‐up. Men and women with high stress were more likely to use antihypertensive medication (1.94; 1.63–2.30), and stressed men were more than two times as likely to develop diabetes during follow‐up (2.36; 1.22–4.59). Conclusion. This longitudinal study supports a causal relation between stress and cardiovascular diseases mediated through unfavourable changes in health behaviour and cardiac risk profile. 相似文献
87.
Matthew S. Comeaux Astrid M. Roy-Engel Dale J. Hedges Prescott L. Deininger 《Genome research》2009,19(4):545-555
The human genome contains nearly 1.1 million Alu elements comprising roughly 11% of its total DNA content. Alu elements use a copy and paste retrotransposition mechanism that can result in de novo disease insertion alleles. There are nearly 900,000 old Alu elements from subfamilies S and J that appear to be almost completely inactive, and about 200,000 from subfamily Y or younger, which include a few thousand copies of the Ya5 subfamily which makes up the majority of current activity. Given the much higher copy number of the older Alu subfamilies, it is not known why all of the active Alu elements belong to the younger subfamilies. We present a systematic analysis evaluating the observed sequence variation in the different sections of an Alu element on retrotransposition. The length of the longest number of uninterrupted adenines in the A-tail, the degree of A-tail heterogeneity, the length of the 3′ unique end after the A-tail and before the RNA polymerase III terminator, and random mutations found in the right monomer all modulate the retrotransposition efficiency. These changes occur over different evolutionary time frames. The combined impact of sequence changes in all of these regions explains why young Alus are currently causing disease through retrotransposition, and the old Alus have lost their ability to retrotranspose. We present a predictive model to evaluate the retrotransposition capability of individual Alu elements and successfully applied it to identify the first putative source element for a disease-causing Alu insertion in a patient with cystic fibrosis. 相似文献
88.
David Gwyn Seymour John M. Starr Helen C. Fox Helen A. Lemmon Ian J. Deary Gordon J. Prescott Lawrence J. Whalley 《Quality of life research》2008,17(1):11-20
Background The direct-weighted Schedule for the Evaluation of Individual Quality of Life, Direct Weighting (SEIQoL-DW) is an individualised
measure of QoL that has been little used in very elderly people.
Methods We administered SEIQoL-DW during Wave 5 of the Aberdeen Birth Cohort 1921 Study (ABC1921) and sought statistical correlations
with other variables in the data set. ABC1921 participants had been IQ-tested in 1932 at age 11. Since 1997, data about cognition,
mental/physical function, personality, health, and socioeconomic status have been gathered in five waves of investigations.
Results Ninety-six out of 98 individuals, mean age 82.2, completed the SEIQoL-DW. Health, family, relationships, finances and social
pastimes were the commonest cues nominated, but age/gender differences existed. The mean SEIQoL-DW score (74.0) was significantly
lower than in an approximately 60% sample from Wave 3, the fall being greater in men. Variables statistically associated with
Wave 5 SEIQoL-DW usually reflected current rather than past status [including Short-Form 36 Health Survey (SF-36) components
and depression], although there were weaker correlations with years of education, housing in childhood, conscientiousness,
and IQ in 1998.
Conclusions SEIQoL-DW proved feasible and acceptable in community-dwelling octogenarians. Recent (i.e. statelike) rather than early or
long-standing (i.e. traitlike) influences appeared to have the greater effect on QoL. 相似文献
89.
C A Prescott 《International journal of pediatric otorhinolaryngology》1992,23(2):141-149
Failure of decannulation after paediatric tracheostomy, once the underlying disorder has resolved, is almost always due to peristomal complications. Granulation tissue formation in the raw tissue of the stoma and its subsequent fibrosis requires removal (50 of the 293 tracheostomies from the Red Cross War Memorial Children's Hospital). It is suggested that this can be avoided by creating a formal skin-to-trachea stoma at the time of tracheostomy. Suprastomal depression of the anterior wall of the trachea (52/293) appears to be unavoidable when using standard tracheostomy tubes. Localised stomal site tracheomalacia and stenosis (numbers of this complication are unknown) results from damage to cartilage of the trachea either by incision or by necrosis from pressure of the tracheostomy tube. Trauma to the cartilage needs to be minimised by careful design of the tracheal incision. It is suggested that consideration should be given to creating a formal tracheostomy stoma for any paediatric tracheostomy that is likely to be required for more than a short period of time. 相似文献
90.