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81.
Provisions of the Drug Regulation Reform Act of 1978 are discussed. Included in the discussion are drug monographs and product licenses, investigations and approvals of drugs, drug information, labeling, promotion and education, penalties, and the National Center for Clinical Pharmacology. The Act eliminates the individual NDA approach to regulation and replaces it with a system of monographs on "drug entities" and "drug product" licenses. It amplifies and redefines the investigational process to facilitate and promote research while protecting patients' rights. It also divides the commercial investigation process into two phases: drug innovation investigations and drug development investigations.  相似文献   
82.
An experimental analogue of a discount drink policy known as the happy hour was used to study the effects of purchase price on drinking behavior. Male volunteers with a prior history of either casual (N=20) or heavy (N=14) drinking were given free access to beverage alcohol during a 20-day period. Approximately half the subjects could purchase alcohol under a single-price condition (50 ¢/drink), while a matched group was given a price reduction daily (25 ¢/drink) during a three-hour period in the afternoon. The results demonstrated that the afternoon price reduction significantly increased alcohol consumption in both casual and heavy drinkers. Reinstatement of the standard purchase price effectively suppressed drinking in both groups. The findings are discussed in terms of the theoretical and research implications of environmental influences on drinking.  相似文献   
83.
The common theoretical speculation that alexithymic personality characteristics (impoverished fantasy life and difficulty expressing feelings verbally) lead to psychosomatic disease was tested in a sample of 181 men. Unlike previous investigations, this study used a measure of alexithymic characteristics taken at least 1 year before any of the men became ill. Comparisons were made of the premorbid MMPI alexithymia scale scores of groups of men who remained well for 10 years or within 10 years developed either physical illness (cancer or benign tumors), "classical" psychosomatic disease (hypertension or gastrointestinal ulcers), or psychiatric disorder (schizophrenia). Results did not support the notion that alexithymia leads to illness onset. There were no significant differences among the groups in their premorbid alexithymia scores. Furthermore, the groups did not differ in the percentage of individuals labeled alexithymic with the use of previously established cut-off points. Although the findings cast doubt on alexithymia as a cause of illness, they do not conflict with the idea that alexithymia can result from the stress of disease or that this type of personality configuration may lead to a decreased response to treatment and a prolonged course of illness.  相似文献   
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An incubation system containing rat jejunoileum was used to determine whether analogues of cyanocabalamin (CNCbl) inhibited the in vitro absorption of CNCbl. The naturally occurring analogues "pseudo B12," "factor A," and the nonnaturally occurring analogue desdemethyl B12, were produced by guided biosynthesis with Propionibacterium arabinosum. Factor B was produced by acid cleavage of cyanocabalamin. Inhibition of Co57-CNBbl uptake was demonstrated for cold CNCbl and for desdemethyl B12, although statistical significance was achieved only for cold CNCbl at 40X and 100X the molar quantity of the radiolabeled CNCbl. However, a trend towards progressive inhibition of specific CNCbl binding was shown as increasing concentrations of CNCbl or desdemethyl B12 were used. No inhibition of specific CNCbl binding could be demonstrated for any of the naturally occurring cobamides tested.  相似文献   
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Background. Abnormalities of the pulmonary arteries following palliative or corrective surgery for tetralogy of Fallot (TOF) are common. Our purpose was to compare the usefulness of magnetic resonance imaging (MRI) and echocardiography in the post- operative evaluation of the pulmonary arteries in children with TOF. Objective. Our hypothesis was that MRI is more sensitive than echocardiography in the detection of branch pulmonary artery abnormalities in children with TOF. Materials and methods. Pulmonary artery MRI and echocardiography were performed in 20 children following palliative and/or corrective surgery for TOF. MRI and echocardiography were compared in their ability to detect abnormalities of the pulmonary arteries. Angiographic or surgical correlation was available in 15 children. A perfusion scan for confirmation of pulmonary artery patency was available in one additional child. Results. Abnormalities of the branch pulmonary arteries identified by MRI included: absence or occlusion (2), focal stenosis (15), hypoplasia (2), aneurysm (1), and non-confluence (1). Echocardiography could not adequately visualize the right and left branch pulmonary arteries in eight and ten children, respectively. Echocardiography missed stenosis in 13 branch pulmonary arteries, patency of hypoplastic pulmonary arteries in two children, non-confluence of the pulmonary arteries in one child, and a left pulmonary artery aneurysm in one child. Abnormalities identified by MRI were confirmed in 16 children by angiography, surgery or perfusion scan. Conclusion. MRI is more sensitive than echocardiography for the evaluation of branch pulmonary artery abnormalities in children following surgery for TOF. Received: 13 January 1997 Accepted: 31 July 1997  相似文献   
90.
Chronic-intermittent hypoxia (CIH) was postulated to evoke c-fos expression in cortical regions that modulate sympathetic discharge. Animals exposed to CIH for 30 days exhibited c-fos labeling in medial prefrontal, cingulate, retrosplenial, and insular cortices. Our findings strongly suggest activation of cortical circuits that adaptively regulate sympathetic and cardiovascular activities.  相似文献   
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