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61.
Rapid transient induction of phenylalanine ammonia-lyase mRNA in elicitor-treated bean cells 总被引:30,自引:0,他引:30 下载免费PDF全文
Edwards K Cramer CL Bolwell GP Dixon RA Schuch W Lamb CJ 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(20):6731-6735
DNAs complementary to a size-selected fraction of poly(A)+ RNA present in elicitor-treated cells of bean (Phaseolus vulgaris L.) were inserted into pAT153 and used to transform Escherichia coli strain C600. Five clones were identified by hybrid-selected translation and cross-hybridization that contained sequences complementary to mRNA encoding phenylalanine ammonia-lyase (EC 4.3.1.5), which catalyzes the first reaction of phenylpropanoid biosynthesis. The longest insert contained a single open reading frame of 1520 base pairs together with 223 base pairs of 3′ untranslated sequence. RNA blot hybridization showed that elicitor caused a rapid, marked but transient increase in phenylalanine ammonia-lyase mRNA that was closely correlated with changes in translatable mRNA activity in vitro and enzyme synthesis in vivo. Blot hybridization of newly synthesized mRNA purified by organomercurial affinity chromatography following in vivo pulse-labeling with 4-thiouridine indicates that elicitor caused a rapid stimulation of phenylalanine ammonia-lyase mRNA synthesis as an early in the defense response leading to accumulation of phenylpropanoid-derived phytoalexins. 相似文献
62.
The United Kingdom and Ireland Trauma & Orthopaedic eLogbook-An evidence base for enhancing training
The United Kingdom and Ireland Trauma and Orthopaedic (T&O) eLogbook was originally conceived over ten years ago in order to provide individual surgeon support and allow national analysis of surgical training experience. Since 2003 every trainee in T&O has been required to submit data recording their operative experience throughout the six years of higher specialist training. We describe how orthopaedic surgeons are using the evidence from the eLogbook to improve training, set operative standards and support consultant (post-specialist registration) revalidation. 相似文献
63.
S. A. Lodhi K. E. Lamb I. Uddin H. U. Meier‐Kriesche 《American journal of transplantation》2012,12(10):2774-2780
Organ storage techniques have been under scrutiny to determine the best preservation method, particularly in donation after cardiac death (DCD) kidneys. Conflicting literature on the benefit of pulsatile perfusion (PP) over cold storage (CS) warrants further investigation. We analyzed the risk of developing delayed graft function (DGF) in recipients of DCD and donation after brain death (DBD) kidneys undergoing PP or CS. We stratified on basis of cold ischemic time (CIT) to determine the interaction of preservation techniques, CIT and DCD kidneys on developing DGF. Of 54 136 recipients, 4923 received DCD kidneys of which 3330 (67%) underwent PP. Of 49 213 DBD recipients, 7531 (15%) underwent PP. DCD had a higher risk of DGF versus DBD (adjusted odds ratio, AOR 3.2; 3.0–3.5). PP kidneys had less DGF (AOR 0.59; 0.56–0.63) compared to CS. Interaction models of method by donor type referenced to PP/DBD revealed CS/DBD kidneys had higher DGF (AOR 1.8; 1.7–1.9), whereas CS/DCD kidneys had the highest risk of DGF (AOR 5.01; 4.43–5.67). Even though suggestive for a benefit of PP on DGF, this retrospective analysis cannot address whether this is an intrinsic effect of PP or is associated with the logistics of PP such as discard of DCD kidneys based on pump parameters. 相似文献
64.
BD Kent EE Eltayeb A Woodman A Mutwali HT Nguyen AG Stack 《American journal of nephrology》2012,36(3):287-295
Background: Chronic obstructive pulmonary disease (COPD) and tobacco use are leading causes of morbidity and mortality. The prevalence and clinical impact of COPD on mortality and kidney transplantation among patients who begin dialysis therapy is unclear. Methods: We explored the clinical impact of COPD and continued tobacco use on overall mortality and kidney transplantation in a national cohort study of US dialysis patients. National data on all dialysis patients (n = 769,984), incident between May 1995 and December 2004 and followed until October 31, 2006, were analyzed from the United States Renal Data System. Prevalence and period trends were determined while multivariable Cox regression evaluated relative hazard ratios (RR) for death and kidney transplantation. Results: The prevalence of COPD was 7.5% overall and increased from 6.7 to 8.1% from 1995-2004. COPD correlated significantly with older age, cardiovascular conditions, cancer, malnutrition, poor functional status, and tobacco use. Adjusted mortality risks were significantly higher for patients with COPD (RR = 1.20, 95% CI 1.18-1.21), especially among current smokers (RR = 1.28, 95% CI 1.25-1.32), and varied inversely with advancing age. In contrast, the adjusted risks of kidney transplantation were significantly lower for patients with COPD (RR = 0.47, 95% CI 0.41-0.54, for smokers and RR = 0.54, 95% CI 0.50-0.58, for non-smokers) than without COPD [RR = 0.72, 95% CI 0.70-0.75, for smokers and RR = 1.00 for non-smokers (referent category)]. Conclusions: Patients with COPD who begin dialysis therapy in the US experience higher mortality and lower rates of kidney transplantation, outcomes that are far worse among current smokers. 相似文献
65.
O'Flaherty LA van Dijk M Albertyn R Millar A Rode H 《Burns : journal of the International Society for Burn Injuries》2012,38(6):840-845
Objective
This observational pilot study investigated effects of aromatherapy massage in paediatric burn patients.Methods
The setting was a 17 beds level I burn unit in Cape Town, South Africa. Between January and October 2009 heart rates and respiratory rates of patients who underwent aromatherapy massage sessions were read before and after the sessions. Primary outcomes were decline in heart rates and respiratory rates, a sign of relaxation. Behavioural responses (sleep/awake state, facial expression, body posture) were documented as secondary outcomes.Results
A convenience sample of 71 paediatric burn patients (median age 3 years) underwent a total of 126 massage sessions. Mean heart rate decreased significantly from 118 (SD 20) to 109 (SD 21), t = 9.8, p < 0.001. Mean respiratory rate decreased significantly from 34 (SD 8) to 30 (SD 8), t = 10.2, p < 0.001. Most massage sessions (92.8%) elicited positive behaviour to the massage, e.g. the child fell asleep, calmed or asked to continue. Nine patients (7.2%) with a median age of 15 months who underwent a single massage session did not show positive behaviour but cried, wriggled or were distressed.Conclusions
Aromatherapy massage seems to be a helpful nonpharmacological approach to reduce hospitalized paediatric burn patients’ distress. Future studies with better research designs and validated outcome measures should confirm our findings. 相似文献66.
Management of mild to moderate aortic valve disease during coronary artery bypass grafting. 总被引:1,自引:0,他引:1
Alsir A M Ahmed Alastair N J Graham Deirdre Lovell Hugh O O'Kane 《European journal of cardio-thoracic surgery》2003,24(4):535-9; discussion 539-40
OBJECTIVE: The long term survival of patients with mild to moderate aortic valve disease who do not have valve replacement at the time of coronary artery bypass grafting (CABG) is unknown. Therefore we have reviewed our experience with such patients. METHODS: We reviewed the medical records of consecutive patients between June 1978 and December 1996, and identified 40 patients with mild to moderate aortic valve disease, who underwent CABG, without valve replacement (study group). Mean preoperative aortic gradient was 34 mmHg and mean intraoperative gradient 20 mmHg. Eleven patients underwent valve inspection, and an equal number, underwent valve repair. The records of 61 other patients with severe aortic valve disease, who underwent concomitant aortic valve replacement (AVR) and CABG (control group), were also reviewed. RESULTS: Survival was significantly better in the control group. Eleven patients (27.5%) in the study group underwent reoperation for AVR, with no operative mortality. Multivariate analysis confirmed valve replacement at initial CABG to be the only predictor of survival (beta=0.586,P=0.038) Preoperative gradient <40 mmHg, intraoperative gradient <20 mmHg, age over 70, sex, aortic stenosis and valve pathology did not predict survival in the study group. CONCLUSION: Patients with mild to moderate aortic valve disease undergoing coronary artery bypass grafting may be best served by valve replacement, rather than repair, inspection or no procedure. 相似文献
67.
Paul Knaapen Mark Lubberink Luuk J. Rijzewijk Rutger W. van der Meer Micheil Unger Tjeerd Germans Jeroen J. Bax Jan W. A. Smit Hildo J. Lamb Albert C. van Rossum Michaela Diamant Frans C. Visser Adriaan A. Larnmertsma 《Journal of nuclear cardiology》2008,15(2):218-224
Background The assessment of forward stroke volume (SV) using dynamic, first-pass cardiac positron emission tomography (PET) was shown
to be feasible in a limited number of studies with small numbers of subjects. The aim of this study was to compare first-pass
derived SV with cardiovascular magnetic resonance imaging (CMR)-obtained values in a larger population of subjects.
Methods and Results Fifty-nine subjects with varying degrees of cardiac function were studied. Stroke volume was assessed using oxygen-15-labeled
water (H2
15O) dynamic first-pass PET for both the right ventricle (RV) and left ventricle (LV), and compared with the findings of aorta
velocity-encoded phase-contrast CMR. The PET-estimated SV was higher for the RV than for the LV (133±34 vs 116±31 mL, P<.01, ±SD), and both were higher compared with values obtained by CMR (81±20 mL, both P<.01,±SD). Although significant, the correlations between PET and CMR were moderate for both the RV (r=0.37, P<.01) and the LV (r=0.40, P<.01,±SD). Bland-Altman analysis revealed a progressive overestimation with increasing SV measured in either ventricle.
Conclusions First-pass dynamic H2
15O PET for the assessment of forward SV is feasible, although values are progressively overestimated with increasing SV, particularly
when the RV is used, and correlations with aorta velocity-encoded phase-contrast CMR are moderate. These findings are probably
protocol-dependent and warrant further study before the use of first-pass dynamic H2
15O PET in clinical or research settings can be advocated. 相似文献
68.
69.
Gibson JN Thomson CE 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2005,26(9):680-690
BACKGROUND: Arthrodesis is the current treatment for end-stage hallux rigidus, although there are many reports advocating total joint replacement arthroplasty. The aim of this randomized controlled trial was to evaluate clinical outcomes after first metatarsophalangeal joint (MTPJ) arthrodesis and replacement arthroplasty. METHODS: Between November, 1998, and January 2001, 63 patients between the ages of 34 and 77 years, with unilateral or bilateral MTPJ arthritis were recruited and randomly selected to have either MTPJ arthrodesis or arthroplasty. Twenty-two patients (38 toes) had arthrodesis and 27 patients (39 toes) had arthroplasty. A single surgeon performed all surgery. The primary outcome measure determining successful surgery was a decrease in pain as measured on a Visual Analogue Scale (VAS). Functional outcome was assessed at 6 months and 1 and 2 years. Cost data were simultaneously collected. RESULTS: At 24 months, pain improved in both groups (p < 0.001), but there were significantly greater improvements after arthrodesis (p = 0.01). All 38 arthrodeses united at a mean dorsiflexion angle of 26 degrees, with few complications. In contrast, in the arthroplasty group, six of the 39 inserted implants had to be removed because of phalangeal component loosening. In the remainder the range of motion gained was poor, and the patients tended to bear weight on the outer border of their foot. The cost ratio was 2:1 in favor of arthrodesis. CONCLUSIONS: Outcomes after arthrodesis were better than those after arthroplasty. The results were partially attributable to an unacceptably high incidence of loosening of the phalangeal components, which resulted in removal of the implants. However, even when data from the failures were excluded, arthrodesis was clearly preferred by most patients. 相似文献
70.
BACKGROUND: Botulinum toxin type A (BTX-A) injections are overwhelmingly safe and effective treatment in cosmetic treatment, but some patients are apprehensive about pain associated with injection. OBJECTIVE: To determine whether preprocedural application of lidocaine 4% topical anesthetic cream to the injection site will reduce pain on injection of BTX-A for the treatment of crow's feet. METHODS: Twenty-four participants receiving bilateral injections for crow's feet were enrolled. Subjects were randomized to one of four study groups. Prior to BTX-A injection, group 1 (n = 6) received lidocaine 4% cream on the right side of the face and vehicle cream on the left side of the face; group 2 (n = 6) received vehicle cream on the right side and lidocaine 4% on the left side; group 3 (n = 6) received lidocaine 4% on both sides; and group 4 (n = 6) received vehicle cream on both sides. RESULTS: We observed a statistically significant reduction in subject-reported procedural pain in participants pretreated with lidocaine 4% on both sides of the face compared with controls. CONCLUSION: Lidocaine 4% cream is effective in reducing the pain associated with BTX-A injection for crow's feet. We encourage further study to clarify the optimal use of topical anesthetics in the practice of cosmetic dermatology. 相似文献