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991.
 Background: According to a recent pupillographic study, patients with Leber’s hereditary optic neuropathy (LHON) show the same pupillary behaviour as normals. Because this raises many questions concerning the real nature of LHON and challenges our concept of the afferent pupillary system, we tried to verify the results of this study. · Methods: Pupillary function was assessed in 34 normal subjects and 40 patients with LHON. Pupillary light reflexes were recorded by means of the Compact Integrated Pupillograph (CIP, AMTech). Under mesopic conditions 200-ms stimuli were presented at two different stimulus intensities. Latency, constriction amplitude and baseline diameter were defined automatically. Pupil light reflexes were compared between LHON patients and normals and between the better and the worse eye in 20 LHON patients with different visual acuities. · Results: For both stimuli there were significant differences in latency between LHON patients and controls. The latency of the pupil light reflex proved to be about 20 ms longer for LHON patients, and the amplitude was significantly smaller for the bright stimulus. Within LHON patients, the eyes with the worse visual acuity had a significantly smaller constriction amplitude than the eyes with the better visual acuity. · Conclusion: The results of our study confirm that LHON really is an optic nerve disease and that the pupillary light reflexes are not normal. Received: 5 January 1998 Revised version received: 28 February 1998 Accepted: 11 March 1998  相似文献   
992.
Summary The case of a male child is reported in which the syndrome of absent pulmonary valve and ventricular septal defect was associated with anomalous drainage of the right superior pulmonary vein into the superior vena cava, atrial septal defect, a right aortic arch, and an aortic isthmic coarctation. The combination of aortic coarctation with a high degree of right-ventricular outflow obstruction has not been reported so far in the literature. This case shows that there is no proof of aplasia of the ductus arteriosus in the syndrome of absent pulmonary valve and ventricular septal defect. Most likely, there is an early involution of the ductus arteriosus; persistence of the ductus arteriosus would not be compatible with fetal survival.  相似文献   
993.
Fast breath-hold cardiovascular magnetic resonance (CMR) shows excellent results for interstudy reproducibility of left ventricular (LV) volumes, ejection fraction, and mass, which are thought to be superior to results of 2-dimensional echocardiography. However, there is no direct comparison of the interstudy reproducibility of both methods in the same subjects. A total of 60 subjects (normal volunteers [n = 20], or patients with heart failure [n = 20] or LV hypertrophy [n = 20]) underwent 2 CMRs and 2 echocardiographic studies for assessment of LV volumes, function, and mass. The interstudy reproducibility coefficient of variability was superior for CMR in all groups for all parameters. Statistical significance was reached for end-systolic volume (4.4% to 9.2% vs 13.7% to 20.3%, p <0.001), ejection fraction (2.4% to 7.3% vs 8.6% to 19.4%, p <0.001), and mass (2.8% to 4.8% vs 11.6% to 15.7% p <0.001), with a trend for end-diastolic volume (2.9% to 4.9% vs 5.5% to 10.5%, p = 0.17). The superior interstudy reproducibility resulted in considerably lower calculated sample sizes (reductions of 55% to 93%) required by CMR compared with echocardiography to show clinically relevant changes in LV dimensions and function. Thus, CMR has excellent interstudy reproducibility in normal, dilated, and hypertrophic hearts, and is superior to 2-dimensional echocardiography.  相似文献   
994.
995.
Opioids induce analgesia by activating opioid receptors not only within the central nervous system but also on peripheral sensory neurons. This study investigated peripherally mediated antinociception produced by the mu-opioid receptor agonist 2-[(4,5alpha-epoxy-3-hydroxy-14beta-methoxy-17-methylmorphinan-6beta-yl)amino]acetic acid (HS-731) after s.c. and oral administration in rats with carrageenan-induced hindpaw inflammation. Antinociceptive effects after s.c. administration were assessed 3 h after intraplantar carrageenan injection and compared with those of centrally acting mu-opioid agonists 14-methoxymetopon and morphine. Opioid agonists caused dose-dependent increases in inflamed paw withdrawal latencies to mechanical and thermal stimulation. The time course of action was different, in that HS-731 (20 microg/kg s.c.) produced significant long-lasting effects up to 4 h after administration, whereas 14-methoxymetopon (20 microg/kg) and morphine (2 mg/kg) reached their peak of action at 10 to 30 min, and their effect declined rapidly thereafter. Subcutaneous administration of the peripherally selective opioid antagonist naloxone methiodide inhibited antinociception elicited by HS-731 (20 microg/kg s.c.), whereas it was ineffective against 14-methoxymetopon (20 microg/kg s.c.). Moreover, the antinociception produced by 100 microg/kg s.c. HS-731 was dose-dependently reversed by s.c. naloxone methiodide. This indicates that HS-731 preferentially activates peripheral opioid receptors, whereas 14-methoxymetopon mediates analgesia via central mechanisms. Orally administered HS-731 significantly reduced hyperalgesia in the inflamed paw induced by carrageenan, which was reversible by s.c. administered naloxone methiodide. These results show that systemic (s.c. and oral) treatment with the mu-opioid agonist HS-731 produces potent and long-lasting antinociception through peripheral mechanisms in rats with carrageenan-induced hindpaw inflammation.  相似文献   
996.
Zusammenfassung Wir bestimmten an sechs Säuglingen im Alter von 6 Monaten die zusätzliche Atemarbeit, die bei Atmung durch Loennecken-Katheter der Charrièrestufen 18, 16, 14 und durch einen neuen Katheter der Stufe 14 mit nur sehr kurzem stenotischem Anteil von den Säuglingen aufgewendet wird. Dabei stellten wir fest, daß im günstigsten Fall bei einem Katheter der Stufe 18 die Atemarbeit verdoppelt und im ungünstigsten Fall bei einem Katheter der Stufe 14 auf das 28fache erhöht wird. Der neue Katheter der Stufe 14 liegt in seiner Wirkung zwischen den Stufen 18 und 16 der Loennecken-Katheter.Ausgeführt mit Mitteln der Deutsehen Forschungsgemeinschaft und der Dr. Karl Wilder-Stiftung des Verbandes der Lebensversicherungsunternehmen e. V.Wir danken unserer technischen Assistentin Frau U.Loebell und Herrn cand. med. K. J.Grusz für ihre Mithilfe bei der Ausführung der Messungen und der Auswertung der Meßergebnisse.  相似文献   
997.
998.
999.
Zusammenfassung In der Medizin, ganz besonders in der Arbeitsmedizin, tritt die Prävention zunehmend in den Vordergrund. Das System der arbeitsmedizinischen Vorsorgeuntersuchungen in der Bundesrepublik Deutschland wird geschildert: 40 Berufsgenossenschaftliche Grundsätze für arbeitsmedizinische Vorsorgeuntersuchungen. 1983 wurden 1,4 Mio., 1984 1,45 Mio. Vorsorgeuntersuchungen registriert. Bei 2, 1 bzw. 1,8 % resultierten gesundheitliche Bedenken, davon 0,9 bzw. 0,8 % nur befristet.In den letzten Jahren wurden bei der Prävention von Gesundheitsschäden am Arbeitsplatz durch normierte und gezielte arbeitsmedizinische Vorsorgeuntersuchungen grosse Fortschritte erzielt. Es handelt sich hierbei auch zukünftig um eine bedeutsame und vielfältige Aufgabe der Arbeitsmediziner.
Programs of health surveillance at the workplace in the Federal Republic of Germany
Summary Prevention is of increasing importance in medicine, particularly in occupational medicine. The programs of health surveillance at the workplace in the Federal Republic of Germany are discussed. In 1983, 1,400,000 examinations of employees were performed; exclusion criteria were fulfilled in 2,1 % (0,9% only temporarily). In 1984 the respective numbers were 1,450,000 examinations (1,8%, 0,8%). During the last few years, health surveillance programs markedly have improved the efficiency of prevention of occupational diseases. They will be an important task for occupational physicians in the future.

Examens médicaux pour la prévention des maladies professionnelles en RFA
Résumé En médecine, et particulièrement en médecine du travail, la prévention prend de plus en plus d'importance. Le présent article traite de l'organisation des examens prophylactiques en République fédérale allemande (RFA) dans le domaine de la médecine du travail: il existe 40 «principes syndicalistes» («Berufsgenossenschaftliche Grundsätze») les concernant. En 1983, 1,4 million d'examens ont été enregistrés, en 1984, 1,45 million. Dans le 2,1% des cas, respectivement le 1,8%, on a dû faire des réserves sur l'état de santé des personnes examinées, réserves temporaires dans le 0,9%, respectivement le 0,8 % des cas.De grands progrès ont été réalisés ces dernières années dans la prévention des maladies professionnelles grâce des contrôles médicaux normalisés et orientés. A l'avenier également, il s'agira là d'une activité importante et variée pour les médecins du travail.
  相似文献   
1000.
Guidewire-Controlled Advancement of the Amplatz Thrombectomy Device   总被引:1,自引:0,他引:1  
The Amplatz Thrombectomy Device (ATD) is a percutaneous rotational catheter proven to homogenize thrombus. The catheter design allows neither application over a coaxial running guidewire nor the use of the device as a monorail system. We report a technical modification that provides guided advancement of the catheter over a wire in order to prevent failure of application and to facilitate the interventional procedure. Received: 0/00/00/Accepted: 0/00/00  相似文献   
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