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The American Cancer Society recently has suggested changes in the frequency of Papanicolaou smear screening which, if followed, would alter current practice considerably. This study assessed the impact of the Papanicolaou smear screening interval on the prevention of advanced disease. Between July 1, 1980 and June 30, 1984, 264 women were evaluated and treated for primary epithelial carcinoma of the cervix (64% had stage I disease). Ninety-seven women (37%) had had a normal Papanicolaou smear within three years of diagnosis, including 48 women (18%) whose last normal Papanicolaou smear was within a year of diagnosis. The cytologic history was unavailable for 81 women (31%). Patients with a screening interval of greater than six years were more likely to be older, of lower socioeconomic status, and black, as compared with patients in the more frequently screened groups. Patients with a screening interval of 36 months or less were similar to those with a 37- to 72-month interval with respect to age, racial characteristics, and socioeconomic status. In this similar group of patients, a screening interval of 37-72 months was associated with a significantly larger proportion of advanced stage disease than found in more frequently screened patients. A policy of screening more frequently than every three years may therefore lead to increased survival among women who develop cervical cancer despite cytologic screening. 相似文献
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Robert M. MacMillan 《The international journal of cardiovascular imaging》1992,8(3):217-227
Ultrafast computed tomography (CT) and magnetic resonance imaging (MRI) generate high resolution tomographic cardiac images. Ultrafast CT requires intravenous injection of x-ray contrast combined with an image acquisition time of 50 msec. MRI requires no contrast injection, but has relatively long acquisition times due to gating. Both technologies can be used to evaluate cardiac chamber and great vessel dimensions, intracardiac and extracardiac masses, ventricular hypertrophy, left ventricular mass, congenital heart disease, regional and global left ventricular function, right ventricular function and pericardium. MRI is highly useful for detection and semi-quantitation of valvular regurgitation while ultrafast CT is not. Aortic and mitral valve stenosis can be detected by both, but MRI is the preferred study. Though both techniques can be used to assess coronary artery bypass graft status, ultrafast CT is the preferred method. It is concluded that ultrafast CT and MRI have broad applications for cardiac diagnosis. 相似文献
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A case is described of the onset of acute renal failure due to renal artery occlusion in a solitary kidney of a sixty-six-year-old woman. She had been treated for severe hypertension due to renal artery stenosis. An aortorenal bypass to revascularized the kidney was combined with repair of an abdominal aortic aneurysm. There was early and full recovery of renal function in the single kidney, and the patient was completely rehabilitated. Review of the literature shows that an aggressive surgical approach to the management of renal artery occlusion is usually followed by excellent results. The pre-existence of renal artery stenosis encourages the formation of a collateral arterial supply which maintains the nutrition of the kidney almost indefinitely, after renal artery occlusion. Revascularization will result in prompt recovery of renal function. 相似文献
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Effect of the 5-lipoxygenase inhibitor ZD2138 on allergen-induced early and late asthmatic responses. 总被引:5,自引:3,他引:2
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S M Nasser G S Bell R J Hawksworth K E Spruce R MacMillan A J Williams T H Lee J P Arm 《Thorax》1994,49(8):743-748
BACKGROUND--Leukotrienes are lipid mediators generated from arachidonic acid by the 5-lipoxygenase pathway which may play an important part in the pathophysiology of asthma. Previous studies have demonstrated attenuation of the allergen-induced early and late asthmatic responses by leukotriene receptor antagonists. The effect of the 5-lipoxygenase inhibitor ZD2138, a non-redox lipoxygenase inhibitor which inhibits leukotriene synthesis for 24 hours after single doses of 350 mg, on allergen-induced early and late asthmatic responses has been assessed. METHODS--Eight asthmatic subjects with baseline FEV1 > 70% were studied. On screening, all subjects developed an allergen-induced biphasic asthmatic response to grass pollen, cat dander, or house dust mite. ZD2138 (350 mg) or placebo was given on two occasions separated by two weeks in a randomised double blind fashion. Allergen inhalation challenge was performed four hours after dosing and FEV1 was measured for eight hours. The inhibitory activity of ZD2138 on the 5-lipoxygenase pathway was assessed by measurements of calcium ionophore-stimulated generation of LTB4 in whole blood ex vivo and by analysis of urinary LTE4 levels before administration of drug or placebo and at regular intervals after oral drug dosing and allergen challenge. RESULTS--ZD2138 produced no significant bronchodilatation or attenuation of the early or late asthmatic response, although there was 82% inhibition of whole blood generation of LTB4 in response to calcium ionophore stimulation and 52% reduction in urinary excretion of LTE4. CONCLUSIONS--In asthmatic subjects the 5-lipoxygenase inhibitor ZD2138 did not protect against allergen-induced asthmatic responses, despite substantial inhibition of 5-lipoxygenase. 相似文献
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M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
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V H MacMillan 《Journal of cerebral blood flow and metabolism》1989,9(2):156-162
This study documents the effects of an intracarotid artery injection of a lethal threshold amount of KCN (2.5 mg.kg-1) on the energy metabolism and histology of the rat brain. This dose of KCN resulted in a rapid abolition of electroencephalographic activity, which remained essentially absent for up to 3 h. Cerebral metabolite measurements 0.25 h after KCN infusion indicated a 52% reduction in cytochrome oxidase activity, a 600% increase in lactate, a 32% reduction in ATP, a 73% increase in ADP, and an 85% decrease in glycogen. Measurements of the above energy metabolites over the ensuing 7 days showed a return to control of all metabolites by 6-24 h. Corresponding to the normalization of energy metabolism was a return of EEG and conscious activity. Histological examination of cyanide-exposed animals revealed a paucity of change with only one animal at 0.5 h showing several dark neurons, two animals at 1 h with minor pallor of corpus callosum and caudate-putamen, and one animal at 48 h with a small hippocampal infarction. It is concluded that it may be impossible to produce a serious enough disruption of cerebral metabolism with KCN injection, to produce neuronal damage by purely "histotoxic" mechanisms. 相似文献