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1.
Lung Cancer ; 124: 148-153, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30268454

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is a major cause of morbidity and mortality in populations eligible for lung cancer screening. The aim of this study was to determine whether a brief CV risk assessment, delivered as part of a targeted community-based lung cancer screening programme, was effective in identifying individuals at high risk who might benefit from primary prevention. METHODS: The Manchester Lung Screening Pilot consisted of annual low dose CT (LDCT) over 2 screening rounds, targeted at individuals in deprived areas at high risk of lung cancer (age 55-74 and 6-year risk ≥1.51%, using PLCOM2012 risk model). All participants of the second screening round were eligible to take part in the study. Ten-year CV risk was estimated using QRISK2 in participants without CVD and compared to age (±5 years) and sex matched Health Survey for England (HSE) controls; high risk was defined as QRISK2 score ≥10%. Coronary artery calcification (CAC) was assessed on LDCT scans and compared to QRISK2 score. RESULTS: Seventy-seven percent (n=920/1,194) of screening attendees were included in the analysis; mean age 65.6 ± 5.4 and 50.4% female. QRISK2 and lung cancer risk (PLCOM2012) scores were correlated (r = 0.26, p < 0.001). Median QRISK2 score was 21.1% (IQR 14.9-29.6) in those without established CVD (77.6%, n = 714/920), double that of HSE controls (10.3%, IQR 6.6-16.2; n = 714) (p < 0.001). QRISK2 score was significantly higher in those with CAC (p < 0.001). Screening attendees were 10-fold more likely to be classified high risk (OR 10.2 [95% CI 7.3-14.0]). One third (33.7%, n = 310/920) of all study participants were high risk but not receiving statin therapy for primary CVD prevention. DISCUSSION: Opportunistic CVD risk assessment within a targeted lung cancer screening programme is feasible and is likely to identify a very large number of individuals suitable for primary prevention.


Assuntos
Doenças Cardiovasculares/diagnóstico , Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico , Idoso , Calcinose , Doenças Cardiovasculares/epidemiologia , Inglaterra/epidemiologia , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Risco , Medição de Risco
2.
Phys Rev Lett ; 108(23): 235004, 2012 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-23003965

RESUMO

The formation of nonrelativistic collisionless shocks in the laboratory with ultrahigh intensity lasers is studied via ab initio multidimensional particle-in-cell simulations. The microphysics behind shock formation and dissipation and the detailed shock structure are analyzed, illustrating that the Weibel instability plays a crucial role in the generation of strong subequipartition magnetic fields that isotropize the incoming flow and lead to the formation of a collisionless shock, similar to what occurs in astrophysical scenarios. The possibility of generating such collisionless shocks in the laboratory opens the way to the direct study of the physics associated with astrophysical shocks.

3.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(2 Pt 2): 025401, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21929052

RESUMO

The acceleration and heating of electrons by an intense laser normally incident on a steep overdense plasma interface is investigated using the particle-in-cell code osiris. Energetic electrons are generated by the laser's electric field in the vacuum region within λ/4 of the surface. Only those electrons which originate within the plasma with a sufficiently large transverse momentum can escape the plasma. This mechanism relies on the standing wave structure created by the incoming and reflected wave and is therefore very different for linear and circularly polarized light.

4.
Phys Rev Lett ; 100(12): 125002, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18517876

RESUMO

Two dimensional particle-in-cell simulations show that laser channeling in millimeter-scale underdense plasmas is a highly nonlinear and dynamic process involving longitudinal plasma buildup, laser hosing, channel bifurcation and self-correction, and electron heating to relativistic temperatures. The channeling speed is much less than the linear group velocity of the laser. The simulations find that low-intensity channeling pulses are preferred to minimize the required laser energy but with an estimated lower bound on the intensity of I approximately 5x10(18) W/cm(2) if the channel is to be established within 100 ps. The channel is also shown to significantly increase the transmission of an ignition pulse.

5.
Phys Rev Lett ; 96(10): 105002, 2006 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-16605742

RESUMO

We consider how an unmagnetized plasma responds to an incoming flux of energetic electrons. We assume a return current is present and allow for the incoming electrons to have a different transverse temperature than the return current. To analyze this configuration we present a nonrelativistic theory of the current-filamentation or Weibel instability for rigorously current-neutral and nonseparable distribution functions, f(0)(p(x), p(y), p(z)) is not equal to f(x)(p(x))f(y)(p(y))f(z)(p(z)). We find that such distribution functions lead to lower growth rates because of space-charge forces that arise when the forward-going electrons pinch to a lesser degree than the colder, backward-flowing electrons. We verify the growth rate, range of unstable wave numbers, and the formation of the density filaments using particle-in-cell simulations.

6.
Aust N Z J Psychiatry ; 14(1): 37-45, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6930258

RESUMO

A consecutive series of 135 suicides is described, this being the total which occurred during one year in Brisbane from 1 March 1973 to 28 February 1974, resulting in a rate of 16 per 100,000. The clinical and social characteristics of the suicides are described. Important contributing factors were depressive illness (55%), physical illness (52%), and drug dependency (34%). About half of the suicides were taking prescribed medication and about a third had been in contact with a doctor shortly before death. Social isolation or loss appeared to contribute to the suicide risk. The study confirms the importance of the recognition and treatment of depressive illness in attempting to prevent suicide and draws attention to the significant contribution of physical illness, especially when affecting the nervous system or gastrointestinal tract, and the importance of the role of alcohol and/or barbiturate dependency.


Assuntos
Suicídio/psicologia , Adulto , Atitude Frente a Saúde , Austrália , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Suicídio/epidemiologia , Tentativa de Suicídio/psicologia
7.
Pathology ; 10(4): 351-63, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-740409

RESUMO

The histochemistry and ultrastructure of calcified cerebellar deposits described by Tonge et al. (1977) are reported. The deposits were located by electron microscopy in the walls of blood vessels outside the basement membrane and, in most lesions, consisted of short fibrillar material arranged in multiple lamellae. A number of nonlaminated small bodies were present also. The material coated the vessel walls discontinuously with major and minor protrusions into adjacent nervous tissue. Histochemical analysis detected the presence of sialopolysaccharides in the lesions in adults and in a case of plumbism in a child, with minor differences in the type of sialic acid. X-ray fluorescence analysis supported by histochemical data indicated that, initially, the calcium was bound to the sialic acid and that calcium phosphate appeared in the lesions at a later date. The authors conclude that the lesion is formed by elaboration of sialopolysaccharides at the site but the possibility was not excluded that the polysaccharide may have been derived from a transudate across the vessel wall.


Assuntos
Calcinose/patologia , Doenças Cerebelares/patologia , Calcinose/etiologia , Calcinose/metabolismo , Cálcio/metabolismo , Doenças Cerebelares/metabolismo , Criança , Humanos , Ferro/metabolismo , Chumbo/metabolismo , Masculino , Fósforo/metabolismo , Polissacarídeos/metabolismo , Ácidos Siálicos/metabolismo
8.
Pathology ; 9(4): 289-300, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-201908

RESUMO

An unusual form of calcification in the cerebellum has been observed in routine autopsies in Queensland over the past 30 years. In 4 surveys carried out at intervals between 1951 and 1976 the lesion has been found microscopically in 10 to 15% of autopsies. There is a significant correlation between cerebellar calcification and raised lead levels in bone.


Assuntos
Calcinose/patologia , Doenças Cerebelares/patologia , Intoxicação por Chumbo/complicações , Adulto , Idoso , Autopsia , Osso e Ossos/análise , Calcinose/etiologia , Cálcio , Doenças Cerebelares/etiologia , Cerebelo/patologia , Criança , Exposição Ambiental , Feminino , Humanos , Corpos de Inclusão , Chumbo/análise , Intoxicação por Chumbo/metabolismo , Masculino , Pessoa de Meia-Idade
10.
Med J Aust ; 2(19): 731-2, 1976 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-794658
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