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91.
Lindeberg S 《Lancet neurology》2003,2(5):273; discussion 273
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92.
On single-photon emission tomography (SPET) examinations with indium-111 pentetreotide, we have often observed a small "hot" spot close to the upper portion of the left kidney. While it was initially believed that this represented a tumour in the tail of the pancreas or in the left adrenal, we now understand that it represents normal adrenal uptake. Since the adrenals have not been described as normally visualised, this uptake may interfere with the interpretation of the examination. We have studied how often the normal adrenals are visualised at such examinations. One hundred consecutive clinical (111)In-pentetreotide examinations in adults including SPET of the abdomen and with normal findings were studied. All examinations with a hot spot attributable to the adrenals were, when available, compared with computed tomography (CT) or magnetic resonance imaging (MRI) of the abdomen performed on clinical grounds within 3 months before or at any time after the scintigraphy. In 11 patients both adrenals were visualised. In 27 patients only the left and in one only the right adrenal was visualised. CT or MRI examinations were available for comparison in 25 of these 39 patients. Two of these showed a pathological finding in the left adrenal. A conservative interpretation is that the normal adrenal is visualised on one or both sides in at least one-quarter of adults at SPET examination with (111)In-pentetreotide.  相似文献   
93.
PURPOSE: To evaluate and compare the ototoxicity and nephrotoxicity of cisplatin and cis-diammineaquachloroplatinum(II) ion (monohydrated complex of cisplatin, MHC, formed in vivo by hydrolysis of cisplatin) after their separate administration to guinea pigs. METHODS: A dose of 4 mg/kg body weight of MHC was deemed suitable for the toxicity evaluation after dose titration. Electrophysiological hearing thresholds (auditory brainstem response, ABR), plasma creatinine and weight were measured in three groups of animals before and after receiving MHC 4 mg/kg (0.0141 mmol/kg), cisplatin 4.24 mg/kg (0.0141 mmol/kg, i.e. equimolar dose) or cisplatin 8 mg/kg (0.0267 mmol/kg) as an i.v. bolus injection. Cisplatin and MHC were analysed using liquid chromatography with post-column derivatization. RESULTS: Administration of MHC 4 mg/kg caused a moderate ABR threshold shift, a significant increase in creatinine and a significant weight loss, changes similar to those seen after administration of cisplatin 8 mg/kg. Animals given cisplatin 4.24 mg/kg had a slight increase in creatinine, but had no ABR threshold shift and gained weight during the experiment. The pharmacokinetic parameters of cisplatin and MHC were estimated after administration of cisplatin 4.24 mg/kg and MHC 4 mg/kg. The area under the blood-ultrafiltrate concentration versus time curve (AUC) for cisplatin after administration of MHC 4 mg/kg was 23% (56+/-5.0 micro g.min.ml(-1)) (means+/-SD) of that after administration of cisplatin 4.24 mg/kg (240+/-25 micro g.min.ml(-1)). The AUC for MHC after administration of cisplatin 4.24 mg/kg was 20% (30+/-4.9 micro g.min.ml(-1)) of that after administration of MHC 4 mg/kg (149+/-26 micro g.min.ml(-1)). CONCLUSIONS: MHC 4 mg/kg causes ototoxicity, nephrotoxicity and weight loss when administered to guinea pigs. The toxic effects were similar to those seen after administration of cisplatin 8 mg/kg and higher than those seen after administration of cisplatin 4.24 mg/kg.  相似文献   
94.
OBJECTIVE: A new tri-leaflet mechanical heart valve made of titanium was inserted in the mitral position to evaluate early results. METHODS AND RESULTS: Five sheep were followed between 3 and 6 months (mean 4.7 months) and performed very well clinically during the follow-up period. In three of five animals a minor para-valvular leakage without hemodynamic importance was observed. The invasive pressure measurements at the end of follow-up revealed only minor transvalvular pressure differences between 1 and 4 mmHg (mean 2.4 mmHg). Similar results were obtained by echo-Doppler technique. Histological examination of the tissue around the valve showed no signs of foreign body reaction or chronic inflammatory reaction. CONCLUSION: This new tri-leaflet heart valve has shown an excellent hemodynamic performance and good tissue compatibility, and therefore may be an alternative to other currently used valve prostheses.  相似文献   
95.
We report a case of recurrent syncope in association with moderate ventricular dysfunction and mild AV-valve regurgitation in an 18-year-old girl, 4 years after she underwent total cavopulmonary connection surgery. Cardiac catheterization revealed a transpulmonary gradient of 1-2 mmHg. During exercise, a dramatic fall in blood pressure and blood oxygenation was observed, paralleled by an increase in heart rate and central venous pressure. Although a slight increase in pulmonary vascular resistance could not be excluded, the reaction was interpreted in terms of an extremely low transpulmonary gradient in association with ventricular dysfunction. Five months after heart transplantation, the patient has been completely free from syncope. Fontan circulation usually involves a delicate haemodynamic situation which may necessitate haemodynamic re-evaluations, including dynamic measurements of the central venous pressure during exercise. Also a moderate ventricular dysfunction may result in compromised pulmonary circulation which in turn may lead to syncope during exercise as a result of insufficient systemic circulation.  相似文献   
96.
97.
Some evidence exists to suggest that serotonin 5-HT2A receptor function is altered in anorexia nervosa and bulimia nervosa. In order to further investigate the 5-HT2A receptor in eating disorders, platelet [3H]lysergic acid diethylamide ([3H]LSD) binding was studied in ten patients with anorexia nervosa, 23 patients with bulimia nervosa and 33 healthy controls. At admission, Bmax for platelet [3H]LSD binding was significantly higher both in the anorexia nervosa group (30.6±4.2 fmol/mg protein; mean±S.D.) and in the bulimia nervosa group (30.8±7.6 fmol/mg protein) than in the control group (23.5 ±6.3 fmol/mg protein; p=0.01 and p=0.003, respectively). Kd was borderline significantly higher among anorexics (median 1.45 nM) and significantly higher among bulimics (median 1.66 nM) than among controls (median 0.95 nM; p=0.05 and 0.003, respectively). The Global Assessment of Functioning score and the body mass index were both significantly negatively correlated to Kd (r=−0.40; p=0.03 and r=−0.41 p=0.03, respectively), but not to Bmax. The present study indicates that patients with anorexia nervosa as well as patients with bulimia nervosa have an enhanced 5-HT2A receptor binding and provides further evidence for a serotonergic dysfunction in eating disorders.  相似文献   
98.
PURPOSE OF REVIEW: The present article presents an accessible review of research results on food hypersensitivity and quality of life (QoL), including 15 original articles on the subject. RECENT FINDINGS: Research on food hypersensitivity and QoL covers children and their parents, adolescents and adults. Several domains of QoL are affected, such as family and social activities, emotional issues and family economy. Food-hypersensitive children are to a large extent limited in their autonomous social activities. Food-allergic adolescents have a higher number of weeks absent from school compared with a control group, and a relatively high percentage of food-allergic young adults do not participate in the labour market. Comorbidity has to be taken into consideration when assessing QoL in food-hypersensitive individuals. Research on gender differences in food hypersensitivity and QoL are scarce. SUMMARY: Although development in this research field has only just begun, it is obvious that food hypersensitivity has a significant impact on individuals' and families' QoL. An important advance is the disease-specific QoL measure instruments that have been created. There is still, however, a need for a more in-depth knowledge as a basis for further development of QoL instruments, and as a basis for societal interventions and family/individual support.  相似文献   
99.
An X-ray fluorescence (XRF) technique using plane polarized X-rays for excitation was used for in vivo measurements of cadmium in the kidney cortex among non-occupationally exposed members of the general population in southern Sweden. The measured concentrations of cadmium in the kidney cortex of smokers (median 28 g/g, n = 10) were significantly higher (P = 0.0036) as compared to those in non-smokers (median 8 g/g, n = 10), and so were the cadmium concentrations in blood and urine. The results show that smoking considerably increases the cadmium concentration in the kidney cortex and that smoking is a major source of cadmium exposure in the general population of Sweden. Except in the presence of very deeply situated kidneys, where the minimum detectable concentration is high, non-invasive in vivo XRF analysis of kidney cadmium should be a useful tool for evaluating the effects of long-term low-level exposure to cadmium and the risk of kidney damage.  相似文献   
100.
Summary The 2A-adrenoceptors in rat spleen, kidney, spinal cord and cerebral cortex were studied using [3H]-RX821002 radioligand binding. In the spleen, spinal cord and cerebral cortex, the ligand bound to saturable sites with a K d of about 1 nmol/l and capacities of 134, 240 and 290 fmol/mg protein, respectively. Computer modelling competition curves for 39 drugs, including those for 2A-, 2B- or 2C-adrenoceptor selective drugs, indicated that the sites labelled by [3H]-RX821002 in the spleen consisted of a single population of 2A-adrenoceptors. However, the competition curves for guanoxabenz were definitely biphasic and resolved into two site fits, indicating that guanoxabenz was binding to both high affinity (K d = 35 nmol/1) and low affinity (K d = 8900 nmol/1) 2A-adrenoceptor sites in the proportions 57% and 43%, respectively. The K d Sfor a number of 2-adrenoceptor subtype selective drugs, measured in competition with [3H]-RX821002 in cerebral cortex and spinal cord, were highly correlated with those obtained in the spleen indicating their 2A-adrenoceptor nature. However, by contrast to the results with the spleen, the guanoxabenz competition curves for the spinal cord and cerebral cortex were monophasic and resolved only into one site fits, the K d of guanoxabenz being about 4000 nmol/l for both tissues. Drug K d Sfor kidney 2A-adrenoceptors were also determined using [3H]-RX821002. For nearly all drugs tested, the K d Swere highly correlated with those found for the 2A-adrenoceptors in the other rat tissues. However, for guanoxabenz, the data indicated that it competed with [3H]-RX821002 at a single 2A-adrenoceptor site with a K d of 39 nmol/1. When the rat 2A-adrenoceptor gene RG20 was transiently expressed in COS-7 cells and its ligand binding properties probed using [3H]-RX821002, the drug K d Sobtained were also highly correlated with those found for the 2A-adrenoceptors in the spleen, cerebral cortex, spinal cord and kidney of the rat. For the RG20 encoded receptor, the guanoxabenz competition curves were steep and monophasic and modelled best into one site fits, with the Kd of guanoxabenz being 5200 nmol/1.It is suggested that guanoxabenz can differentiate between two forms of 2A-adrenoceptors in the rat: 2A1 and 2A2. The 2A1-form is present in the spleen and kidney where it shows a high apparent affinity for guanoxabenz. The 2A2-form shows a low apparent affinity for guanoxabenz and is present in the spleen, cerebal cortex and spinal cord. The 2A2-form of the rat 2-adrenoceptor appears to be encoded by the RG20 gene. The 2A, and 2A2-adrenoceptor forms do not represent high and low affinity receptor forms for agonists because assays included EDTA, Gpp(NH)p and Na+, which eliminated the high affinity receptors for agonists.  相似文献   
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