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31.
BACKGROUND--Women appear to be increasingly susceptible to snoring and sleep disordered breathing after the menopause. This observation, coupled with the considerable sex difference in sleep apnoea, may be explained on the basis of a protective effect of female hormones. This study was carried out to determine whether hormone replacement therapy has a role in the management of obstructive sleep apnoea in postmenopausal women. METHODS--The effect of short-term (mean (SE) 50 (3) days) hormone replacement therapy with either oestrogen alone or in combination with progesterone on sleep disordered breathing was investigated in 15 postmenopausal women with moderate obstructive sleep apnoea. The effect of treatment on the ventilatory response to hypoxia and hypercapnia was assessed in 10 patients. RESULTS--There was no reduction in the clinical severity of obstructive sleep apnoea after hormone treatment despite an increase in the serum oestrogen level from 172 (23) to 322 (33) pmol/l. There was a small but clinically insignificant reduction in the apnoea/hypopnoea index during REM sleep from 58 (6) to 47 (7). There was no difference in response between the oestrogen only group and the oestrogen plus progesterone group. Hypercapnic ventilatory responsiveness did not change with hormone treatment, but an change with hormone treatment, but an increase in hypoxic ventilatory responsiveness was observed. CONCLUSIONS--These data indicate that short-term hormone replacement is unlikely to have an effective role in the clinical management of postmenopausal women with obstructive sleep apnoea. The observed reduction in the apnoea/hypopnoea index during REM sleep, however, suggests that longer term treatment, or the use of higher doses, may have an effect.  相似文献   
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Magnetic resonance imaging (MRI) has taken its place beside computed tomography (CT) and ultrasonography in effective imaging of the central nervous system in infants and children. The major initial impact of MRI in pediatric neuroradiology has been the displacement or replacement of the more expensive and invasive procedures such as angiography, myelography, cisternography, and ventriculography. Ultrasonography remains the screening procedure for fetal and infant central nervous system abnormalities, whereas CT continues to be an effective brain screening technique after loss of the ultrasonography windows with growth of the child. The better the clinical information transmitted to the radiologist in advance of imaging of the patient, the more likely the clinician will receive valuable information in return.  相似文献   
34.
Adenosine as a vasodilator in primary pulmonary hypertension   总被引:7,自引:0,他引:7  
BACKGROUND. The acute administration of vasodilator drugs to patients with primary pulmonary hypertension has been advocated to identify those with reversible pulmonary vasoconstriction. Unfortunately, the usefulness of the drugs currently available is limited by accompanying systemic hypotension. A vasodilator with effects confined to the pulmonary circulation would therefore be advantageous in such patients. METHODS AND RESULTS. The purine nucleoside adenosine was infused into the pulmonary artery in seven patients with primary pulmonary hypertension (baseline pulmonary vascular resistance [PVR], 442-1,295 dyne/cm/sec-5) to determine its effect on PVR. In all patients, there was a dose-dependent and significant reduction (mean maximal percent decrease from baseline, 38.9%; p less than 0.001) in PVR mediated through a decrease in pulmonary artery pressure and an increase in cardiac output. Systemic vascular resistance (SVR) also decreased, but the ratio of PVR to SVR decreased (maximal mean percent decrease from baseline) by 10.5% (p less than 0.025), indicating that adenosine has a preferential vasodilator effect on the pulmonary circulation when administered in this manner. CONCLUSIONS. Because of its pharmacokinetic and vasodilator properties, adenosine may have a specific role in the investigation of primary pulmonary hypertension.  相似文献   
35.
The effects of haloperidol on motor and functioning and cognitive functioning were studied in young (3-5 months old) and aged (20-22 months old) male mice by examining haloperidol-induced catalepsy and haloperidol-induced decrements in performance on a radial arm maze. The aged mice were much more sensitive to these adverse effects of haloperidol than were the young mice. Studies of the distribution of radioactivity from [3H]haloperidol to the brain indicated that the differences in sensitivity to this drug were not due to pharmacokinetic differences. The results demonstrate that mice are suitable for studies of aging-induced changes in the behavioral effects of neuroleptic agents.  相似文献   
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Effects of corticosteroids in acute severe asthma.   总被引:2,自引:0,他引:2       下载免费PDF全文
N C Barnes 《Thorax》1992,47(8):582-583
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38.
Four patients with erythema induratum (EI) have been diagnosed at the Dermatology Department within the past two years. All four patients had a history of recurrent painful nodules on their calves for at least three years before diagnosis. Three of the patients, all with positive Mantoux reaction to tuberculin skin tests, had neither a personal or family history of tuberculosis. The other patient who had a six year history of recurrent painful leg nodules developed a tuberculous breast abscess. There was a dramatic response to anti-tuberculous chemotherapy in all four patients but one subsequently had recurrent nodules which spontaneously subsided without further chemotherapy.  相似文献   
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The long-acting analogue of luteinizing hormone releasing hormone, D-Trp6-Pro9-NEt-LHRH (LHRHa), is effective in the short-term treatment of central precocious puberty. We report the results of two to four years of LHRHa therapy in 27 children with this disorder. Secondary sex characteristics regressed in most patients. Sex steroid levels and basal and LHRH-stimulated gonadotropin levels remained suppressed compared with pretreatment values. Linear growth rates decreased from 11.0 +/- 0.8 (SEM) cm/yr before treatment to 5.7 +/- 0.4 cm/yr at two years of treatment and 3.7 +/- 0.7 cm/yr at four years of treatment. Predicted heights by the Bayley-Pinneau method increased from 156.4 +/- 2.0 cm before treatment to 162.3 +/- 2.3 cm at two years and 163.4 +/- 2.4 cm at three years. Five patients treated for four years had a mean increase in predicted height of 5.5 cm. To date no adverse effects have been observed. However, the ultimate safety of this analogue is not known. We conclude that LHRHa appears to be an effective long-term therapy for central precocious puberty.  相似文献   
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