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81.
Anxiety in patients undergoing MR imaging   总被引:6,自引:0,他引:6  
Quirk  ME; Letendre  AJ; Ciottone  RA; Lingley  JF 《Radiology》1989,170(2):463-466
To determine and quantify the major sources of anxiety for patients undergoing magnetic resonance (MR) imaging and to suggest means by which to eliminate or diminish their negative effects, the authors studied anxiety in 46 subjects. Of these, 20 randomly selected subjects who successfully completed the examination participated in exit interviews. Six subjects who terminated the examination before completion also completed exit interviews. Pre-imaging and postimaging questionnaires (state-trait anxiety inventory) were administered to measure anxiety in the 20 other subjects. Anxiety was associated with the constrictive dimensions of the magnet bore, examination duration, coil noise, and temperature within the bore. Preparation at the point of referral was consistently absent, incomplete, or misleading. Patients used identifiable strategies to cope with the examination: blinding, breathing relaxation techniques, visualization of pleasant images, and performance of mental exercises.  相似文献   
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SUMMARY The efficacy and safety of the methylprednisolone prodrugs methylprednisolone suleptanate and methylprednisolone sodium succinate were evaluated in a multicentre, randomised, double-blind, double-dummy parallel study of 88 patients hospitalised with acute asthma. Each study drug was administered as a bolus intravenous injection of 40mg methylprednisolone equivalents every 6 hours for 48 hours. Methylprednisolone 32mg was administered orally 6 hours after the last dose. Pulmonary function, medical events, and clinical laboratory values were assessed at predefined intervals before and during the 72-hour study. The primary response measure of pulmonary function was per cent predicted forced expiratory volume in one second (FEV1) at 48 hours. Secondary response measures were peak expiratory flow rate (PEFR) and FEV1/forced vital capacity (FVC) ratio. Although both drugs demonstrated within-group mean changes from baseline (starting at 6 hours) that were statistically significant for each response, there were no statistically significant differences between the two groups. The mean percent predicted FEV1 at 48 hours and mean per cent change from baseline were 64% and 13% (p<0.0001) for the methylprednisolone suleptanate group and 67% and 17% (p<0.0001) for the methylprednisolone sodium succinate group, respectively. The mean PEFR and FEV1/FVC ratio at 48 hours were 5.77 l/s and 73% for the methylprednisolone suleptanate group and 5.78 l/s and 76% for the methylprednisolone sodium succinate group, respectively. There were no clinically or statistically significant between-group differences in any of the safety parameters. In this study, methylprednisolone suleptanate and methylprednisolone sodium succinate have been shown to be therapeutically equivalent in the treatment of patients hospitalized with acute asthma.  相似文献   
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SUMMARY Major depression can impair an individual's motivation to perform routine daily activities and cause a deterioration in cognitive and psychomotor function. Some antidepressants add to pathological dysfunction through unwanted side-effects. Although most patients eventually recover as a simultaneous consequence of tolerance and therapeutic response, some may not. Where side-effects continue to retard normal recovery they can be called behaviourally toxic, which can be classified as disruptive, inhibitory or provocative. Disruptive behavioural toxic effects are measured using either psychometric tests or simulations of real-life activities (for example, a driving test). There are no widely-accepted tests for inhibitory or provocative behavioural toxicity, and assessments of antidepressants are made on the basis of case studies. This review summarises the results of psychometric and real-life simulation tests and compares the effects of antidepressants on behaviour competence. The purpose is to identify those drugs that seem to be the most and least likely to produce behavioural toxicity.  相似文献   
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A sterilisable radiation probe of small dimensions was designed to locate the lesions at orthopaedic surgical sites according to the procedure of intraoperative bone scintigraphy. The probe has a collimated opening 2 mm in diameter. It is connected to a portable radioactivity counter which converts the disintegration rates detected at surgical sites into an acoustic signal that increases steeply with increasing disintegration rate. The acoustic signal enables the surgeons and isotope specialists to readily monitor radioactivity in the region of interest without attention being distracted from the surgical site. Dimethylaminodiphosphonate (designated SF44) was the osteotropic radiopharmaceutical chosen for carrying out intraoperative bone scintigraphy, since the available data show that this chemical increases the pathological: normal bone uptake ratio of the lesion by 25% compared to the usual diphosphonates. Forty-seven orthopaedic interventions were carried out according to the intraoperative bone scintigraphy procedure. They showed that this procedure facilitated the rapid location of the lesion, the objective termination of the operation, less frequently the reduction in dimension of the excised areas, and rarely the simplification of the surgical technique. Practice of intraoperative bone scintigraphy requires proper training and caution.  相似文献   
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Platelets have a central role in the development of arterial thrombosis and subsequent cardiovascular events. An appreciation of this complex process has made antiplatelet therapy the cornerstone of cardiovascular disease management. However, numerous patients will experience a recurrent atherothrombotic vascular event despite adequate antiplatelet therapy. Individual differences in the rate of platelet activation and reactivity markedly influence normal hemostasis and the pathological outcome of thrombosis. Such an individual variability is largely determined by environmental and genetic factors. These are known to either hamper platelets' response to agonists, and thereby mimic the pharmacological modulation of platelet function or mask therapy effect and sensitize platelets. In this article, we reviewed the antiplatelet mechanisms of aspirin and clopidogrel and the possible role of different polymorphisms, which may affect the efficacy of antiplatelet therapy. Heterogeneity in the way patients respond to aspirin and clopidogrel may in part reflect variation in cyclooxygenase (COX)-1, COX-2, glycoprotein (GP) Ib alpha, GP Ia/IIa, GP IIb/IIIa, UGT1A6*2, P2Y1, P2Y12, CYP2C9, CYP3A4 and CYP3A5 genotypes.  相似文献   
89.
Patients with chromosome 22q11 deletion syndrome exhibit significant phenotypic variability. Epidemiologic data suggest a higher incidence in Hispanics, but limited clinical information is available from Latin-American patients. We describe the clinical features of Chilean patients with 22q11 deletion syndrome and compare their findings with those reported in large European, Japanese and US series. Data were obtained from 208 patients from five medical centers. Mean age at diagnosis was 5.2 years, with a median of 2.3 years. Congenital heart defects were present in 59.6%, lower than other large series that averaged 75.8%. Palate abnormalities were present in 79%, higher than previous reports averaging 56%. Patients with congenital heart disease were diagnosed earlier (median 0.3 years of age) than those without heart defects (median 5.6 years) and had greater mortality attributable to the syndrome (9.8% vs 2.4%, respectively). The differences in frequencies of major anomalies may be due to growing awareness of more subtle manifestations of the syndrome, differences in clinical ascertainment or the presence of modifier factors. These observations provide additional data useful for patient counseling and for the proposal of health care guidelines.  相似文献   
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