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61.
62.
W. E. Adam M. Clausen D. Hellwig E. Henze F. Bitter 《European journal of nuclear medicine and molecular imaging》1988,13(12):637-647
Myocardial scanning (MS) and radionuclide ventriculography (RNV) are the foundation of nuclear cardiology. These procedures aim in two completely different directions: RNV tries to image heart motion, that is, mechanical (pump) function, and therefore belongs to the group of first-order functional imaging (FI, imaging mechanical function), whereas MS is based on myocardial metabolism, and therefore can be attributed to third-order functional imaging (metabolism). This statement is relevant for the assessment of the clinical position of RNV: Third-order (metabolism) functional imaging is the domain of nuclear medicine (NM), whereas first-order FI has to face the competition of alternative noninvasive procedures such as ultrasound (US), digital subtraction angiography (DSA), computer tomography (CT), and nuclear magnetic resonance (NMR). The domain of RNV includes stages two (acute infarction) and three (postinfarction period) of coronary arterial disease (CAD). The advantageous combination of quantitative data on global, left ventricular (LV) function and imaging of regional motion ensures the superiority of RNV over US. However, RNV is inferior to MS in physical examinations in the preinfarction stage of CAD, whereas US is clearly inferior to both NM procedures. Recent progress could be attained by gated SPECT (GASPECT). A proposal is presented for simplification of this time-consuming procedure. Technetium-labeled isonitriles offer the chance for the combination of perfusion-motion imaging of the myocardium. However, even standard RNV offers new possibilities. The multitude of parameters produced by quantitation has not yet been exploited completely. This can be done by discriminant analysis. The computer finds out an optimal subset from the whole set of parameters for the solution of a significant clinical problem. The software learns to find the label of a special pathognomonic entity. This computer work is supported by a relational data bank (Oracle) and an optical disk. Two examples for the effectiveness of the computer in problem solving are presented. It is concluded that RNV, even in the very competitive class of first-order functional imaging, enjoys a preferred position. The future indeed seems brighter because labeled isonitriles offer the chance for the combination of perfusion-motion imaging of the myocardium.Dedicated to Prof. Heinz Hundeshagen on the occasion of his 60th birthday 相似文献
63.
We believe that rejuvenation of the shapes and volumes of the face is just as important as "tightening of the skin and muscles". In this way a more complete rejuvenation effect is obtained which is better perceived by others. The SMO technique provides a solution by the use of malleable coral microgranules, which may constitute the first biomaterial of a new generation of plastic and malleable onlays. In this context, a more general volumetric concept of ageing is developed, leading to a modification in our consultation and our treatment. Most importantly, this approach opens a whole new field, that of preventative treatment of facial ageing, which will no doubt be multidisciplinary. 相似文献
64.
Summary Hypertension was induced in uninephrectomized rats by NaCl 0.9% drinking and deoxycorticosterone acetate (DOCA) administration for 6 weeks. Plasma renin activity was markedly reduced but not suppressed. Renal renin concentration and total renal renin content were moderately reduced. Intravenous injection of 0.2 ml of antiangiotensin plasma resulted in transitory hypotension both in salt and DOCA-treated rats, and in normotensive control rats. It is concluded that angiotensin participates in the maintenance of blood pressure in salthypertensive rats as well as in normal animals.This work was supported by grant 67-00-517 from D.G.R.S.T. (Délégation Générale à la Recherche Scientifique et Technique). The authors wish to thank Miss colette Innocenzi and Miss Sonia Culot for technical assistance. 相似文献
65.
Atypical sexual behavior during sleep 总被引:5,自引:0,他引:5
OBJECTIVE: This article reports a case series of atypical sexual behavior during sleep, which is often harmful to patients or bed partners. METHODS: Eleven subjects underwent clinical evaluation of complaints of sleep-related atypical sexual behavior. Complaints included violent masturbation, sexual assaults, and continuous (and loud) sexual vocalizations during sleep. One case was a medical-legal case. Sleep logs, clinical evaluations, sleep questionnaires, structured psychiatric interviews, polysomnography, actigraphy, home electroencephalographic monitoring during sleep, and clinical electroencephalographic monitoring while awake and asleep were used to determine clinical diagnoses. RESULTS: Atypical sexual behaviors during sleep were associated with feelings of guilt, shame, and depression. Because of these feelings, patients and bed partners often tolerated the abnormal behavior for long periods of time without seeking medical attention. The following pathologic sleep disorders were demonstrated on polysomnography: partial complex seizures, sleep-disordered breathing, stage 3 to 4 non-rapid eye movement (REM) sleep parasomnias, and REM sleep behavior disorder. These findings were concurrent with morning amnesia. CONCLUSIONS: The atypical behaviors were related to different syndromes despite the similarity of complaints from bed partners. In most cases the disturbing and often harmful symptoms were controlled when counseling was instituted and sleep disorders were treated. In some cases treatment of seizures or psychiatric disorders was also needed. Clonazepam with simultaneous psychotherapy was the most common successful treatment combination. The addition of antidepressant or antiepileptic medications was required in specific cases. 相似文献
66.
Ammonium perchlorate (AP) and sodium chlorate (SC) have been detected in public drinking water supplies in many parts of the United States. These chemicals cause perturbations in pituitary-thyroid homeostasis in animals by competitively inhibiting iodide uptake, thus hindering the synthesis of thyroglobulin and reducing circulating T(4) (thyroxine). Little is known about the short-term exposure effects of mixtures of perchlorate and chlorate. The present study investigated the potential for the response to a mixture of these chemicals on the pituitary-thyroid axis in rats to be greater than that induced by the individual chemicals. Adult male F-344 rats were exposed, via their drinking water, to the nominal concentrations of 0.1, 1.0, 10 mg/L AP or 10, 100, 1000 mg/L SC and their mixtures for 7 days. Serum T(4) levels were significantly (p < 0.05) reduced in rats following exposure to the mixtures, but not after exposure to the individual chemicals. Serum T(3) (triiodothyronine) was not altered by treatment and TSH (thyroid stimulating hormone) was only increased after the high-dose chlorate treatment. Histological examination of the thyroid gland showed colloid depletion and hypertrophy of follicular epithelial cells in high-dose single chemical and all mixture-treated rats, while hyperplasia was observed only in some of the rats treated with mixtures (AP 10 + SC 100, AP 0.1 + SC 1000, and AP 10 + SC 1000 mg/L). These data suggest that short-term exposure to the mixture of AP and SC enhances the effect of either chemical alone on the pituitary-thyroid axis in rats. 相似文献
67.
68.
Contribution of redox-active iron and copper to oxidative damage in Alzheimer disease 总被引:1,自引:0,他引:1
Castellani RJ Honda K Zhu X Cash AD Nunomura A Perry G Smith MA 《Ageing research reviews》2004,3(3):319-326
Metal-catalyzed hydroxyl radicals are potent mediators of cellular injury, affecting every category of macromolecule, and are central to the oxidative injury hypothesis of Alzheimer disease (AD) pathogenesis. Studies on redox-competent copper and iron indicate that redox activity in AD resides exclusively within the neuronal cytosol and that chelation with deferoxamine, DTPA, or, more recently, iodochlorhydroxyquin, removes this activity. We have also found that while proteins that accumulate in AD possess metal-binding sites, metal-associated cellular redox activity is primarily dependent on metals associated with nucleic acid, specifically cytoplasmic RNA. These findings indicate aberrations in iron homeostasis that, we suspect, arise primarily from heme, since heme oxygenase-1, an enzyme that catalyzes the conversion of heme to iron and biliverdin, is increased in AD, and mitochondria, since mitochondria turnover, mitochondrial DNA, and cytochrome C oxidative activity are all increased in AD. These findings, as well as studies demonstrating a reduction in microtubule density in AD neurons, suggest that mitochondrial dysfunction, acting in concert with cytoskeletal pathology, serves to increase redox-active heavy metals and initiates a cascade of abnormal events culminating in AD pathology. 相似文献
69.
70.
Association between hormonal changes at menopause and the risk of a coronary event: a longitudinal study 总被引:1,自引:0,他引:1
OBJECTIVE: To investigate the association of hormone levels at menopause, lifestyle variables, and body composition with the predicted 10-year risk of a coronary event, calculated using the PROCAM scoring system, in a population-based sample of Australian-born, middle-aged women. DESIGN: A 9-year prospective study of 438 Australian-born women, who at baseline were aged 45 to 55 years and had menstruated in the prior 3 months. Interviews, fasting blood, and physical measurements were taken annually. The risk of an acute coronary event was calculated using the PROCAM scoring system (includes: age, low-density lipoprotein cholesterol, smoking, high-density lipoprotein cholesterol, systolic blood pressure, family history of premature myocardial infarction, diabetes mellitus, and triglycerides). RESULTS: Retention rate after 8 years of follow-up was 88% (n = 387). In women not using hormone therapy (HT): higher than average body mass index (BMI) (P < 0.001), BMI that increased (P < 0.005), lower than average estradiol levels (P < 0.005), estradiol levels that decreased (P < 0.001), and high free testosterone levels (P < 0.05) were associated with increased risk of a coronary event. There was a trend for high exercise frequency to be associated with a decreased risk (P < 0.07). After BMI and lifestyle variables were taken into account, use of HT did not have a significant effect on risk of a coronary event. CONCLUSION: In this longitudinal observational study of middle-aged Australian-born women, high BMI, an increase in BMI, high free testosterone, low estradiol, and a decrease in estradiol levels were the main determinants of increased risk of an acute coronary event, based on the PROCAM scoring system calculation. More frequent exercise tended to lower the risk. 相似文献