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131.
SR Kulkarni MS Gohel RA Bulbulia MR Whyman KR Poskitt 《Annals of the Royal College of Surgeons of England》2009,91(3):210-213
INTRODUCTION
Early carotid endarterectomy (CEA) in symptomatic patients may prevent repeat cerebral events. This study investigates the relationship between waiting time for CEA and the incidence of repeat cerebral events prior to surgery in symptomatic patients.PATIENTS AND METHODS
A prospective database of consecutive patients undergoing CEA between January 2002 and December 2006 was reviewed. Repeat event rates prior to surgery were calculated using Kaplan–Meier analysis and predictive factors identified using Cox regression analysis.RESULTS
A total of 118 patients underwent CEA for non-disabling stroke, TIA and amaurosis fugax. Repeat cerebral events occurred in 34 of 118 (29%) patients at a median 51 days (range, 2–360 days) after the first event. The estimated risk of repeat events was 2% at 7 days and 9% at 1 month after first event (Kaplan–Meier survival analysis). Age (HR 1.059; 95% CI 1.014–1.106; P = 0.009] was identified as a predictor of repeat events. Patients underwent surgery at median 97 days (range, 7–621 days) after the first event. Eleven of 60 (18%) patients waiting ≤?97 days for surgery and 23 of 58 (40%) patients waiting >?97 days had repeat events. (P = 0.011, chi-squared test).CONCLUSIONS
Delays in surgery should be reduced in order to minimise repeat cerebral events in patients with symptomatic carotid stenosis, particularly in the elderly population. 相似文献132.
RA Pearl W Townley D Stott AO Grobbelaar 《Annals of the Royal College of Surgeons of England》2009,91(6):494-499
INTRODUCTION
Accurate clinical diagnosis depends on the reliable recognition of signs and symptoms. This expertise comes from experience in seeing patients which has been traditionally gained over a long training period. Shortened specialist training (Modernising Medical Careers) has led to a greater reliance on structured teaching and skills transfer programmes. The accuracy of clinical diagnosis and the rate at which diagnostic skills improve during training is important for the assessment of trainees, and the delivery of care.PATIENTS AND METHODS
This study assessed the accuracy of clinical diagnosis of skin lesions by two junior plastic surgery trainees. They were asked to diagnose 120 consecutive skin lesions seen in a pigmented skin lesion clinic in 2005, with the histological diagnosis being confirmed following subsequent excision. The process was repeated a year later in 2006 to enable the rate of correct diagnosis to be compared.RESULTS
Initially, 53.3% of diagnoses were correct. A year later, this had risen to 65.0%. Twenty-two different skin pathologies were present in excised specimens, and skin cancers comprised 30%. The trainees demonstrated 93.8% sensitivity in their initial diagnosis of malignancy (95% CI, 79.2–99.2) and 97.4% a year later (95% CI, 86.5–99.9). However, specificity was 69.3% (95% CI, 58.6–78.7) in 2005 and 71.6% (95% CI, 60.5–71.4) in 2006.CONCLUSIONS
Accuracy in the diagnosis of the wide range of skin conditions presenting to an out-patient clinic was shown to increase over a 1-year period. We feel that this improvement resulted from regular clinical exposure supported by a structured learning programme. The shortening of the specialist training period may affect the acquisition of diagnostic skills by trainees and impact on the confidence with which they commence consultant practice. 相似文献133.
134.
Cademartiri F La Grutta L Runza G Palumbo A Maffei E Mollet NR Bartolotta TV Somers P Knaapen M Verheye S Midiri M Hamers R Bruining N 《European radiology》2007,17(7):1842-1849
Attenuation variability (measured in Hounsfield Units, HU) of human coronary plaques using multislice computed tomography
(MSCT) was evaluated in an ex vivo model with increasing convolution kernels. MSCT was performed in seven ex vivo left coronary
arteries sunk into oil followingthe instillation of saline (1/∞) and a 1/50 solution of contrast material (400 mgI/ml iomeprol).
Scan parameters were: slices/collimation, 16/0.75 mm; rotation time, 375 ms. Four convolution kernels were used: b30f-smooth,
b36f-medium smooth, b46f-medium and b60f-sharp. An experienced radiologist scored for the presence of plaques and measured
the attenuation in lumen, calcified and noncalcified plaques and the surrounding oil. The results were compared by the ANOVA
test and correlated with Pearson’s test. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated.
The mean attenuation values were significantly different between the four filters (p < 0.0001) in each structure with both solutions. After clustering for the filter, all of the noncalcified plaque values (20.8 ± 39.1,
14.2 ± 35.8, 14.0 ± 32.0, 3.2 ± 32.4 HU with saline; 74.7 ± 66.6, 68.2 ± 63.3, 66.3 ± 66.5, 48.5 ± 60.0 HU in contrast solution)
were significantly different, with the exception of the pair b36f–b46f, for which a moderate-high correlation was generally
found. Improved SNRs and CNRs were achieved by b30f and b46f. The use of different convolution filters significantly modifief
the attenuation values, while sharper filtering increased the calcified plaque attenuation and reduced the noncalcified plaque
attenuation. 相似文献
135.
RA Stein 《Clinical genetics》2009,75(2):121-123
Age-related macular degeneration is associated with an unstable ARMS2 ( LOC387715 ) mRNA
Fritsche et al. (2008)
Nature Genetics 40 (7): 892–896 相似文献
Fritsche et al. (2008)
Nature Genetics 40 (7): 892–896 相似文献
136.
RA Kumar 《Clinical genetics》2009,76(6):499-501
137.
RA Coleman 《British journal of pharmacology》2009,158(1):180-182
The mechanism of the long duration of action of salmeterol at β2-adrenoceptors has long been a matter of debate, and is still unresolved. Szczuka and colleagues have both summarized the position to date and suggested a new mechanistic contender, receptor rebinding. Despite this, they still do not come to any clear conclusion. Much of the literature data that they have drawn upon appears contradictory, and mathematical models are inevitably flawed by the questionable validity of key values applied to them. Although the issue will undoubtedly eventually be resolved, it will probably require investigators to apply carefully designed studies on simple experimental systems such as isolated membranes or cultured cells. Only then should studies be extended to more complex systems such as isolated preparations of airways smooth muscle, where tissue bulk inevitably presents a complicating factor, particularly where relatively lipophilic compounds are concerned. 相似文献
138.
KD McCloskey UA Anderson RA Davidson YR Bayguinov KM Sanders SM Ward 《British journal of pharmacology》2009,156(2):273-283
Background and purpose:
W/Wv and wild-type murine bladders were studied to determine whether the W/Wv phenotype, which causes a reduction in, but not abolition of, tyrosine kinase activity, is a useful tool to study the function of bladder interstitial cells of Cajal (ICC).Experimental approach:
Immunohistochemistry, tension recordings and microelectrode recordings of membrane potential were performed on wild-type and mutant bladders.Key results:
Wild-type and W/Wv detrusors contained c-Kit- and vimentin-immunopositive cells in comparable quantities, distribution and morphology. Electrical field stimulation evoked tetrodotoxin-sensitive contractions in wild-type and W/Wv detrusor strips. Atropine reduced wild-type responses by 50% whereas a 25% reduction occurred in W/Wv strips. The atropine-insensitive component was blocked by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both tissue types. Wild-type and W/Wv detrusors had similar resting membrane potentials of −48 mV. Spontaneous electrical activity in both tissue types comprised action potentials and unitary potentials. Action potentials were nifedipine-sensitive whereas unitary potentials were not. Excitatory junction potentials were evoked by single pulses in both tissues. These were reduced by atropine in wild-type tissues but not in W/Wv preparations. The atropine-insensitive component was abolished by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both preparations.Conclusions and implications:
Bladders from W/Wv mice contain c-Kit- and vimentin-immunopositive ICC. There are similarities in the electrical and contractile properties of W/Wv and wild-type detrusors. However, significant differences were found in the pharmacology of the responses to neurogenic stimulation with an apparent up-regulation of the purinergic component. These findings indicate that the W/Wv strain may not be the best model to study ICC function in the bladder. 相似文献139.
140.