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71.
According to the consensus statement on the diagnosis of multiple system atrophy (MSA), erectile dysfunction is required for male patients to fulfil the urinary incontinence criterion. However, there is no equivalent item for female patients. We questioned 19 female patients with MSA of the parkinsonian type (MSA-P), 28 female patients with Parkinson's disease (PD), and 27 healthy controls on their genital sensitivity. A total of 47% of the MSA patients but only 4% of the PD patients and 4% of the control group admitted to reduced genital sensitivity, a highly significant difference (P < 0.001). Moreover, the appearance of reduced genital sensitivity in female MSA patients showed a close temporal relation to the onset of the disease. If these preliminary results can be confirmed and further specified in a larger sample, a historical item of reduced genital sensitivity in female patients might become a diagnostic feature for MSA, comparable to erectile dysfunction in male patients.  相似文献   
72.
Previous studies in rats using the Morris water maze suggested that the processing of spatial information is modulated by corticosteroid hormones through mineralocorticoid and glucocorticoid receptors in the hippocampus. Mineralocorticoid receptors appear to be involved in the modulation of explorative behaviour, while additional activation of glucocorticoid receptors facilitates the storage of information. In the present study we used the water maze task to examine spatial learning and memory in mice homozygous and heterozygous for a targeted disruption of the glucocorticoid receptor gene. Compared with wild-type controls, homozygous and heterozygous mice were impaired in the processing of spatial but not visual information. Homozygous mutants performed variably during training, without specific platform-directed search strategies. The spatial learning disability was partly compensated for by increased motor activity. The deficits were indicative of a dysfunction of glucocorticoid receptors as well as of mineralocorticoid receptors. Although the heterozygous mice performed similarly to wild-type mice with respect to latency to find the platform, their strategy was more similar to that of the homozygous mice. Glucocorticoid receptor-related long-term spatial memory was impaired. The increased behavioural reactivity of the heterozygous mice in the open field points to a more prominent mineralocorticoid receptor-mediated function. The findings indicate that (i) the glucocorticoid receptor is of critical importance for the control of spatial behavioural functions, and (ii) mineralocorticoid receptor-mediated effects on this behaviour require interaction with functional glucocorticoid receptors. Until the development of site-specific, inducible glucocorticoid receptor mutants, glucocorticoid receptor-knockout mice present the only animal model for the study of corticosteroid-mediated effects in the complete absence of a functional receptor.  相似文献   
73.
74.
An RF excitation pulse for three-dimensional (3D) time-of-flight (TOP) MR angiography (MRA) with a nonlinear excitation profile was numerically calculated under the condition of uniform vessel signal across the excitation volume (slab), and the superiority of the optform pulse as compared with conventional RF pulses and TONE pulses was demonstrated. For this purpose we acquired MRA of the lower leg and of the carotid and vertebral arteries in a 30-year-old healthy volunteer. Although the flow velocity ranges in these two anatomic locations are different by about a factor of 10, in both cases the corresponding optform pulse provided the best signal homogeneity at the highest level.  相似文献   
75.
76.
Abstract:  Liver transplantation for hepatitis B virus (HBV)-related liver disease has changed from a contraindication to outcomes comparable with non-HBV-related liver transplantations during the last two decades. Mainly the implementation of immunoprophylaxis with hepatitis B immunoglobulin (HBIG) and the use of nucleoside analogs such as lamivudine and adefovir account for this dramatic change. The standard of care in most centers today consists of lamivudine treatment in replicating hepatitis B pre-orthotopic liver transplantation (OLT) and a combination regimen of lamivudine and HBIG post-OLT. With adefovir, a potent antiviral drug became available in recent years that allows for the treatment of patients with lamivudine-resistant tyrosine-methionine-aspartate-aspartate (YMDD)-mutant HBV. In the transplantation setting, first studies indicate that a triple prophylactic therapy consisting of lamivudine, adefovir, and HBIG will become the standard of care for YMDD-mutant-related hepatitis B. With new drugs emerging for the treatment of chronic HBV, there is optimism for new options also in the transplant setting.  相似文献   
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78.
The Pocone gold minings are situated in the Bento Gomes River Basin, at the border of the Pantanal of Mato Grosso. Gold-bearing quartz veins are removed from the subsoils, milled with water, centrifuged and the heavier fraction is subsequently mixed with mercury for gold separation. The gold mining activities caused a very intensive landscape change, threatening many environmental processes like sediment control and storage and recycling capacity of mercury. Cold Vapor Atomic Fluorescence System (CVAFS) was used to determinate total mercury in water, suspended material and sediments from Bento Gomes River, sampled monthly for 1 year. Apart from the fact that mercury concentrations are low in water and bottom sediments, they are slightly higher in relation to background levels measured in the area. The concentration in suspended material is also lower than other rivers with gold mining activities, but the floodplains of the Bento Gomes River act as mercury sinks. Therefore, the discharge of mercury into the Pantanal floodplain should be avoided, in spite of actual contamination of the system being very low.  相似文献   
79.
Subjective work noise: A major risk factor in myocardial infarction   总被引:5,自引:0,他引:5  
Summary The relationship between subjective work noise exposure and the risk of myocardial infarction (MI) was assessed in a population based casecontrol study. 395 MI patients (31–65 years) were compared to 2148 controls from a random population sample with the same age/sex distribution. The relative risk (RR) for MI—adjusted for control variables (smoking, age, social status, etc.)—was found to increase significantly and steadily with noise category. Subjective work noise exposure was the second greatest risk factor for MI after smoking. Possible bias due to overreporting of subjective noise exposure is discussed. Interdisciplinary studies on the relationship between cardiovascular diseases and workrelated stressors including subjective and objective noise assessment are needed to quantify the risk of MI due to work noise.
Zusammenfassung In einer bevölkerungsbezogenen Fall-Kontroll-Studie wurde der Zusammenhang zwischen der subjektiven Arbeitslärmbelastung und dem Herzinfarktrisiko untersucht. 395 Herzinfarktpatienten im Alter von 31 bis 65 Jahren wurden mit 2148 Kontrollpersonen aus einer Zufallsstichprobe mit gleicher Alters- und Geschlechtsverteilung verglichen. Das relative Risiko für Herzinfarkt—adjustiert bezüglich mehrerer Einflussvariablen wie Rauchen, Alter, Sozialstatus usw.—stieg signifikant und monoton mit der Arbeitslärmbelastung an. Die subjektive Arbeitslärmbelastung erwies sich als der zweitwichtigste Risikofaktor für Herzinfarkt nach dem Rauchen. Mögliche Fehler wie z.B. Überbewertung der subjektiven Lärmbelastung werden diskutiert. Interdisziplinäre Studien zum Zusammenhang zwischen kardiovaskulären Erkrankungen und arbeitsplatzbezogenen Stressoren mit Erfassung der subjektiven und der objektiven Lärmbelastung sind notwendig, um das Herzinfarktrisiko durch Arbeitslärm zu quantifizieren.

Résumé Le rapport entre la perception subjective de bruit gênant et le risque d'infarctus du myocarde (IM) fait l'objet d'une étude comparative portant sur 395 malades (IM) âgés de 31 à 65 ans et 2148 cas témoins sortis d'un sondage aléatoire parmi la population générale tout en assurant la même distribution d'âge et de sexe. II s'avère que—après la rectification exigée par les variables telles que consommation de tabac, âge, couche sociale, etc.—le risque relatif (RR) de IM augmente de manière significative et constante avec le gêne causé par le bruit au lieu de travail. Pour le IM, la perception subjective du bruit vécu au lieu de travail est le deuxième facteur de risque, son importance n'étant dépassée que par le tabagisme. Les auteurs discutent l'incidence possible d'une notification exagérée de bruit gênant. Afin de calculer le risque d' IM attributable au bruit perçu au lieu de travail, des études interdisciplinaires devraient être réalisées pour examiner les liens entre les maladies cardiovasculaires et les stresseurs liés au travail, y compris l'évaluation subjective et objective du bruit.
  相似文献   
80.
Frontal stimulation, i.e. electrical stimulation where electrodes are pressed on the skin of the intact frontal skull of mice or rats, may represent a more humane alternative to the widely used transcorneal stimulation to induce electroshock seizures. The aim of this work was to directly compare transcorneal and frontal stimulation in eliciting maximal electroshock-induced seizures (MES) in mice and the anticonvulsant effect of carbamazepine (CBZ) and phenytoin (PHT) on thus produced seizures. In addition, we stimulated mice and rats repeatedly via transcorneal and frontal electrodes to see whether kindling is produced by this procedure. Two electroshock tests were used in mice, i.e. maximal electroshock seizure threshold (MEST) test and MES generated by supramaximal stimulation (50 mA). Frontal stimulation resulted in lower convulsive threshold than in the case of corneal stimulation. Both CBZ and PHT produced dose-dependent increases in seizure threshold for both sites of stimulation, i.e. transcorneal and frontal. As regards type of electrodes, higher doses of PHT were required to increase seizure threshold in the case of frontal than transcorneal stimulation. Supramaximal stimulation (50 mA) yielded comparable ED50 values regardless of the site of stimulation. Furthermore, once-daily stimulation of mice, regardless of the placement of electrodes, did not induce any changes in convulsive threshold. We also attempted to kindle mice and rats via corneal and frontal electrodes by repetitive electrical stimulation using currents which initially did not produce generalized clonic seizures. Mice were stimulated once daily for 2 s with 3 mA (corneal electrodes) or 2 mA (frontal electrodes) and rats were stimulated twice daily for 4 s at 8 mA (corneal electrodes) or 5 mA (frontal electrodes). With corneal stimulation in rats there was a clear progression of kindling development which was not the same in nature when compared with corneally-stimulated mice. Frontal stimulation did not produce kindling. Moreover, corneal stimulation was better tolerated by rats, while in mice high mortality was seen after either method of current delivery. Our data indicate that frontal electrodes can be used as an alternative to transcorneal stimulation to produce MES by supramaximal or threshold current intensities as screening procedures in antiepileptic drug (AED) development. Nevertheless, this type of stimulation cannot be used to produce minimal electroshock seizures and seems not to be useful to produce kindling in rats and mice.  相似文献   
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