Previous trials of antiplatelet therapy for the prevention of venous thromboembolism have individually been inconclusive, but a meta-analysis of their results indicated reductions in the risks of ...deep-vein thrombosis and of pulmonary embolism in various high-risk groups. The aim of this large randomised placebo-controlled trial was to confirm or refute these apparent benefits.
During 1992-1998, 148 hospitals in Australia, New Zealand, South Africa, Sweden and the UK randomised 13,356 patients undergoing surgery for hip fracture, and 22 hospitals in New Zealand randomised a further 4088 patients undergoing elective arthroplasty. Study treatment was 160 mg daily aspirin or placebo, started preoperatively and continued for 35 days. Patients received any other thromboprophylaxis thought necessary. Follow-up was of mortality and of in-hospital morbidity up to day 35.
Among the patients with hip fracture, allocation to aspirin produced proportional reductions in pulmonary embolism of 43% (95% CI 18-60; p=0.002) and in symptomatic deep-vein thrombosis of 29% (3-48; p=0.03). Pulmonary embolism or deep-vein thrombosis was confirmed in 105 (1.6%) of 6679 patients assigned aspirin compared with 165 (2.5%) of 6677 assigned placebo, which represents an absolute reduction of 9 (SE 2) per 1000 and a proportional reduction of 36% (19-50; p=0.0003). Similar proportional effects were seen in all major subgroups, including patients receiving subcutaneous heparin. Aspirin prevented 4 (1) fatal pulmonary emboli per 1000 patients (18 aspirin-group vs 43 placebo-group deaths), representing a proportional reduction of 58% (27-76; p=0.002), with no apparent effect on deaths from any other vascular cause (hazard ratio 1.04 95% CI 0.86-1.26) or non-vascular cause (1.01 0.84-1.23). Deaths due to bleeding were few (13 aspirin vs 15 placebo), but there was an excess of 6 (3) postoperative transfused bleeding episodes per 1000 patients assigned aspirin (p=0.04). Among elective-arthroplasty patients, rates of venous thromboembolism were lower, but the proportional effects of aspirin were compatible with those among patients with hip fracture.
These results, along with those of the previous meta-analysis, show that aspirin reduces the risk of pulmonary embolism and deep-vein thrombosis by at least a third throughout a period of increased risk. Hence, there is now good evidence for considering aspirin routinely in a wide range of surgical and medical groups at high risk of venous thromboembolism.
This paper presents studies of Bose–Einstein correlations (BEC) in proton–proton collisions at a centre-of-mass energy of 13 TeV, using data from the ATLAS detector at the CERN Large Hadron Collider. ...Data were collected in a special low-luminosity configuration with a minimum-bias trigger and a high-multiplicity track trigger, accumulating integrated luminosities of 151
μ
b
-
1
and 8.4 nb
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1
, respectively. The BEC are measured for pairs of like-sign charged particles, each with
|
η
|
<
2.5
, for two kinematic ranges: the first with particle
p
T
>
100
MeV and the second with particle
p
T
>
500
MeV. The BEC parameters, characterizing the source radius and particle correlation strength, are investigated as functions of charged-particle multiplicity (up to 300) and average transverse momentum of the pair (up to 1.5 GeV). The double-differential dependence on charged-particle multiplicity and average transverse momentum of the pair is also studied. The BEC radius is found to be independent of the charged-particle multiplicity for high charged-particle multiplicity (above 100), confirming a previous observation at lower energy. This saturation occurs independent of the transverse momentum of the pair.
Repair of a groin hernia is one of the most common elective operations performed in general surgery. Our aim was to compare laparoscopic repair with open repair of groin hernia.
At 26 hospitals in ...the UK and lreland, 928 patients with groin hernia were randomly assigned to laparoscopic repair (n=468) or open hernia repair (n=460, of which 433 were tension-free mesh repairs). Patients were clinically assessed at 1 week and 1 year after surgery, and were sent questionnaires at 3 months and 1 year. The primary endpoints were: complications: return to usual activities of social life (as the most generally applicable example of return to usual activities); hernia recurrence; groin pain that persisted at 1 year; and costs to the health services. All analyses were by intention to treat.
At 1 week, at least one complication was found in 108 (29·9%) patients allocated to laparoscopic repair and in 155 (43·5%) patients allocated to open repair (95% CI for difference −20·6% to −6·6%, p<0·001). There were three serious surgical complications all of which occurred in the laparoscopic group. Patients in the laparoscopic group returned to the usual activities of social life sooner than the patients in the open repair group (10 IQR 7–21 vs 14 7–28 days, p=0·004). At 1 year after the operation, the laparoscopic group had a lower rate of persistent groin pain than those who had open repair (28·7% vs 36·7% 95% CI for difference −14·7% to −1·4%, p=0·0018). Hwever, all seven hernia recurrences occurred in the laparoscopic group not in the open repair group 1·9% vs 0·0% 95% Clfor difference 0·5% to 3·4%, p=0·0017).
Although laparoscopic hernia repair has advantages for patients, concerns about safety indicate that open repair is the more appropriate option for the general surgeon. Our findings lend support to the move towards laparoscopic hernia surgery becoming part of the domain of specialist surgeons.
We perform the first detailed three-dimensional simulation of low Mach number convection preceding runaway thermonuclear ignition in a mixed H/He X-ray burst. Our simulations include a ...moderate-sized, approximate network that captures hydrogen and helium burning up through rp-process breakout. We look at the difference between two- and three-dimensional convective fields, including the details of the turbulent convection.
Argues that the interpretative methodology used by the Cambridge School (CS) & Quentin Skinner could improve the study of the history of political thought in International Relations (IR). To fully ...understand a text, it is necessary to focus on the linguistic context in which it was produced & to gain an understanding of its locutionary & illocutionary meanings. Though the CS historians are praised for their methodology for the context of writing, they are criticized for placing too little emphasis on intellectual traditions & the context of reception. Using the speech-act theory, Skinner demonstrates the role of language in molding & determining action. It is argued that Skinner's historical-interpretative methodology should be incorporated in a general project of critique. I. Sharp
This study is a 7.5-year follow-up of a population-based series of twins with multiple sclerosis (MS) whose mean age now exceeds 50 years. The twin pairs were identified through the Canadian ...nationwide system of MS clinics and were drawn from a population of 5,463 patients. After 7.5 years, the monozygotic concordance rate increased from 25.9 to 30.8% and the dizygotic-like sex concordance rate from 2.4 to 4.7%. These results are very similar to those of other population-based studies and to our own modified replication twin data reported here. We interpret the data to mean that MS susceptibility is genetically influenced, and a single dominant or even a single recessive gene is unlikely to account for this effect. The difference in concordance rates suggests that at least two or more genes are operative. These data also have important implications for the nature of the environmental effect(s) in MS susceptibility. Most monozygotic twins are discordant even after a correction for age and magnetic resonance imaging findings. This unambiguously demonstrates the powerful effect of nonheritable factors.
. There is increasing evidence that phosphorus has been accumulating in the surface horizons of agricultural soils to the extent that some soils represent a potential diffuse source of pollution to ...surface waters. The relationships between equilibrium phosphorus concentration at zero sorption (EPC 0) of soil and a number of soil physicochemical variables were investigated in the surface layers of arable and grassland agricultural soils sampled from the Thame catchment, England. Soil EPC0 could be predicted from an equation including soil test (Olsen) P, soil phosphate sorption index (PSI) and organic matter content (OM) (R2=0.88; P<0.001) across a range of soil types and land use. The simple index Olsen P/PSI was found to be a good predictor of EPC0 (R2=0.77; P<0.001) and readily desorbable (0.02 m KCl extractable) P (R2=0.73; P<0.001) across a range of soil types under arable having soil organic matter contents of <10%.
The cardiac troponin T (TnT) I79N mutation has been linked to familial hypertrophic cardiomyopathy and a high incidence of sudden death, despite causing little or no cardiac hypertrophy. In skinned ...fibers, I79N increased myofilamental calcium sensitivity (Miller, T., Szczesna, D., Housmans, P. R., Zhao, J., deFreitas, F., Gomes, A. V., Culbreath, L., McCue, J., Wang, Y., Xu, Y., Kerrick, W. G., and Potter, J. D. (2001)J. Biol. Chem. 276, 3743–3755). To further study the functional consequences of this mutation, we compared the cardiac performance of transgenic mice expressing either human TnT-I79N or human wild-type TnT. In isolated hearts, cardiac function was different depending on the Ca2+ concentration of the perfusate; systolic function was significantly increased in Tg-I79N hearts at 0.5 and 1 mmol/liter. At higher Ca2+ concentrations, systolic function was not different, but diastolic dysfunction became manifest as increased end-diastolic pressure and time to 90% relaxation.In vivo measurements by echocardiography and Doppler confirmed that base-line systolic function was significantly higher in Tg-I79N mice without evidence for diastolic dysfunction. Inotropic stimulation with isoproterenol resulted only in a modest contractile response but caused significant mortality in Tg-I79N mice. Doppler studies ruled out aortic outflow obstruction and were consistent with increased chamber stiffness. We conclude that in vivo, the increased myofilament Ca2+ sensitivity due to the I79N mutation enhances base-line contractility but leads to cardiac dysfunction during inotropic stimulation.
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