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991.
Uwe Helber M.D. Jaqueline Loichat M.D. Ioakim Spyridopoulos M.D. Peter E. Huppert M.D. Hans Martin Hoffmeister M.D. 《The International journal of angiology》1998,7(2):169-172
The certain diagnosis of cardiac amyloidosis is only possible with myocardial biopsy, even if echocardiographic studies often show a typical sparkling pattern. Using magnetic resonance imaging (MRI) we examined if there is a specific morphological pattern in patients with amyloidosis compared with patients with hypertrophic cardiomyopathy (LVH). With a 1.0 T magnetom and FISP 2D sequences two patients with biopsy-proven cardiac amyloidosis (AL), two patients with generalized AL and suspected cardiac AL, and five patients with LVH were examined and data were compared with echocardiography. In two cases with cardiac AL, contrast medium (Gd-DTPA) was given and dynamic-turbo-flash-sequences were obtained. In patients with AL, both ventricles were hypertrophied, whereas in the cases of hypertrophy due to other reasons only the left ventricle was hypertrophied. The systolic wall thickening was in all cases of amyloidosis below 30%. In contrast to echocardiography, a myocardial sparkling pattern in amyloidosis was not found with MRI. Even with additional contrast examination we could not differentiate the types of hypertrophy by imaging solely the left ventricular wall. There is no specific myocardial pattern in cardiac amyloidosis neither in standard MRI nor after examination with additional contrast medium, but concomitant right ventricular (RV) and left ventricular (LV) hypertrophy is a typical observation in these patients.Presented at the 37th Annual World Congress, International College of Angiology, Cologne, Germany, June 1996. 相似文献
992.
Jürgen Martens Uwe Kramer Anja Gertje Martina Schütte 《Macromolecular chemistry and physics.》1993,194(2):475-484
Acrylamides containing heteroatoms N, S or O are effective compounds to influence the properties of polymers. On the one hand they determine the chemical and physical behaviour of the synthetic materials, on the other hand they offer new possible applications for such compounds. In this paper a synthetic method affording a new class of monomers prepared from simple educts is described. Thus, 3-thiazolines 3 are allowed to react with alkenoyl chlorides (e. g. acryloyl chloride) to give 3-alkenoyl-4-chlorothiazolidines. Upon hydrolysis the 3-alkenoyl-4-hydroxythiazolidines 6a–d , 7a , b , 8a–d and 9a , b are obtained. Starting from 3-alkenoyl-4-chlorothiazolidines, several 3-alkenoyl-4-methoxythiazolidines 6e , f , 7c and 9c have been synthesized, too. 相似文献
993.
Uwe Helmert und Eberhard Greiser 《Sozial- und Pr?ventivmedizin》1988,33(4-5):233-240
Zusammenfassung In den fünf DHP-Studienregionen Spandau, Bremen, Traunstein, Stuttgart und Karlsruhe/Bruchsal/Mosbach wurde vor Beginn der Intervention in den Jahren 1984–1986 jeweils ein Gesundheitssurvey an einer repräsentativen Bevölkerungsstichprobe der Altersgruppe 25–69 Jahre durchgeführt. Untersucht wurden dabei insgesamt 11527 Personen. Zwischen den fünf Studienregionen existieren markante soziostrukturelle Unterschiede. Bei einer ökologischen Analyse zwischen den Merkmalen der sozialen Schicht und der Prävalenz der KHK-Risikofaktoren treten keine signifikanten Zusammenhänge auf. Erst bei einem Pooling der Daten zeigen sich für beide Geschlechter deutliche Assoziationen zwischen den sozioökonomischen Variablen und den mehr verhaltensbezogenen Risikofaktoren Zigarettenrauchen und Übergewicht, während für die Hypertonie und die Hypercholesterinämie keine signifikanten schichtspezifischen Unterschiede hervortraten. Der Anteil der Personen mit drei und mehr KHK-Risikofaktoren war deutlich höher in den unteren sozialen Schichten. Aus diesen Resultaten ist für die DHP-Interventionsstudie die Konsequenz zu ziehen, nach Möglichkeit in stärkerem Masse soziale Gruppen mit eher ungünstiger sozioökonomischer Basis anzusprechen.
Social group and risk factors for coronary heart diseases: Results of a health survey in Western Germany
Summary Prior to the start of the intervention activities in the five study regions of the German Cardiovascular Prevention Study (GCP), health surveys of representative samples of the population (25 to 69 years) were carried out between 1984 and 1986. In all, 11,527 persons participated in the study. Important socio-structural differences existed between the five study regions. An ecological analysis relating social class characteristics to the prevalence of CHD-risk factors did not show any significant findings. However, a pooling of the data of the five study regions resulted in the demonstration, for both sexes, of a significant association of social class with cigarette smoking and overweight. Hypertension and hypercholesterolemia were not related to social class. The proportion of persons with three or more CHD-risk factors was clearly higher in lower social classes. These findings point to the need for risk factor intervention strategies focusing more on the lower social classes in order to achieve more adequate prevention of coronary heart disease.
Appartenance sociale et facteurs de risque pour les maladies coronariennes: résultats d'une enquête de santé en Allemagne Fédérale
Résumé Avant le commencement de l'intervention, dans les années 1984–1986, on a établi tout d'abord le bilan de santé d'un échantillon représentatif de la population (de 25 à 69 ans) domiciliée dans les cinq régions sur lesquelles porte le programme allemand de prévention des maladies cardiovasculaires; à savoir Berlin-Spandau, Bremen, Traunstein, Stuttgart et Karlsruhe/Bruchsal/Mosbach. Au total 11527 personnes ont été examinées. Il existe de notables différences socio-structurelles entre les cinq régions de l'étude. Une analyse écologique ne fait pas apparaître de relation significative entre les catégories de couches sociales et la prévalence des facteurs de risque. Toutefois, un «pooling» des données provenant des cinq centres montre, pour les deux sexes, une relation évidente entre les variables socio-économiques et les facteurs de risque liés au comportement qui sont le tabagisme et l'excès pondéral. Tandis que pour l'hypertension et l'hypercholestérolémie aucune différence significative n'est apparue entre les couches sociales. La proportion des personnes ayant trois facteurs de risque et plus était sensiblement plus élevée parmi les couches inférieures de population. Ces résultats montrent que le programme de prévention doit mettre l'accent sur les groupes sociaux économiquement défavorisés.相似文献
994.
Uwe -Peter Ketelsen Dieter Schmidt 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1972,185(3):245-268
Zusammenfassung Bei einem 54jährigen Patienten mit dystrophischer Myotonie bestanden ophthalmoskopisch Pigmentierungen und leichte Aufhellungen des Maculabereiches. Erst fluorescenzangiographisch zeigten sich deutlich sternförmige, asymmetrische Degenerationen.Das bei der Ptosisoperation gewonnene Muskelgewebe des M. orbicularis oculi wurde elektronenmikroskopisch untersucht. Im M. orbicularis überwiegen degenerative vor atrophischen Prozessen. Keine der pathologischen Reaktionen ist als Einzelbefund spezifisch für die myotone Dystrophie. Erst die Gesamtheit der muskelcellulären Befunde ergibt ein bei diesem Krankheitsbild wiederkehrendes Reaktionsmuster, wie es teilweise von der peripheren Muskulatur bekannt ist. Neben den muskelcellulären Veränderungen wurden regenerative Vorgänge in Form von verschmelzenden Myoblasten nachgewiesen. Degenerative Veränderungen an den Myelinscheiden der Nerven werden in Zusammenhang mit der muskelcellulären Reaktion zur Diskussion gestellt.
Für Ihre freundliche Unterstützung bei der Ausführung dieser Arbeit danken wir Frau Prof. Dr. E. Freund-Mölbert (Institut für Biologie II der Universität Freiburg).
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Ocular symptoms and electron microscopic results of the orbicularis oculi in myotonic dystrophy
Summary A 54 year old patient with a myotonic dystrophy ophthalmoscopically showed pigmentations and light spots of the macular region. Distinct asymmetrical degenerations with stellate configuration of this region could be seen (only by fluoreszence angiography).The muscle tissue of the m. orbicularis oculi which was gained by ptosis operation was investigated by electron microscopy. In the m. orbicularis degenerative processes are prevalent over atrophic changes. None of the pathological reactions is on its own specific for the myotonic dystrophy. Only the whole of the muscle cellular findings show a recurring pattern which is partly known from the peripheral musculature. Besides the muscle-cellular changes, regeneration in the form of fusing myoblasts were found. Degenerations of the nerves' myelin-sheaths are discussed in context with muscle cellular reaction.
Für Ihre freundliche Unterstützung bei der Ausführung dieser Arbeit danken wir Frau Prof. Dr. E. Freund-Mölbert (Institut für Biologie II der Universität Freiburg).
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
995.
996.
Infiltration patterns of macrophages and lymphocytes in chronically rejecting rat kidney allografts 总被引:1,自引:0,他引:1
Uwe W. Heemann Stefan G. Tullius Takuya Tamatami Masayuki Miyasaka Edgal Milford Nicholas L. Tilney 《Transplant international》1994,7(5):349-355
The migration of circulating leukocytes to sites of inflammation or antigen is based, at least in part, on the activities of adhesion molecules. In the context of organ transplantation, some of these have been shown to be upregulated during acute allograft rejection. As their role during chronic rejection has not been examined, we have used an established rat model to compare sequentially the presence of host cells within the grafts, as defined immunohistologically, with patterns of in vitro leukocyte binding and their dependence upon particular adhesion molecules. Various donor populations of peripheral blood lymphocytes (PBL), lymph node lymphocytes (LNL), and splenic monocytes were interacted with snap-frozen sections of allografted, isografted, and native kidneys at serial intervals up to 24 weeks after transplantation. Monocyte binding in the allografts rose at 8 weeks and peaked at 12 weeks, a period preceding the maximum numbers of macrophages noted immunohistologically in the chronically rejecting grafts at 16 weeks. Lymphocyte binding and infiltration patterns were similar, remaining stable throughout the follow-up period and consistently greater than those noted in isografts. In vitro binding of the monocytes was inhibited by mAbs against ICAM-1, LFA-1, CD18, and MAC-1; MAC-1 did not influence lymphocyte binding, although the other mAbs were effective. We conclude that adhesion molecules are responsible, at least in part, for patterns of cell populations infiltrating chronically rejecting renal allografts. 相似文献
997.
Sonja Grunewald Uwe Paasch Hans‐Jürgen Glander 《Journal der Deutschen Dermatologischen Gesellschaft》2007,5(1):15-21
The dermatologist employs systemic agents with likely gametotoxic side effects, including cytotoxic, immunosuppressive, immunomodulatory and biological agents. The impact of chemotherapy on male fertility depends on the treatment protocol as well as the pre‐treatment spermatogenesis status. Sperm concentration starts to drop about 2 weeks after beginning chemotherapy and reaches a maximum after 2–3 months. About half show recovery after 12–36 months. One year after therapy is completed, a treated patient has no increased risk of fathering a malformed child. There are no reports of methotrexate patients fathering children with malformations, most likely because impaired fertility or embryogenesis arrest. Cryopreservation of male gametes should be recommended prior to cytotoxic treatment, since the likelihood of post‐treatment fertility is unpredictable. The cryopreservation causes a loss of vital spermatozoa by 30–70% but does not influence the genetic information of gametes. Males treated with retinoids have no reproductive safety risk. Biologicals inhibiting TNF α show a positive effect on sperm function in vitro. 相似文献
998.
Nicole Lindenblatt Uwe Platz Jörn Hameister Ernst Klar Michael D. Menger Brigitte Vollmar 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(3):285-295
Background and aims Cigarette smoking is linked to thromboembolic events; however, a relationship between nicotine exposition and thrombosis has
not been established. Thus, we intended to study the effect of acute and chronic nicotine application in an in vivo mouse
model.
Materials and methods In microvessels of the dorsal skin fold chamber, light-dye-induced thrombus formation was analyzed using intravital fluorescence
microscopy. Male and female C57BL/6J mice received nicotine chronically via the drinking water (100 μg/ml) for 8 weeks. An
additional series of experiments was performed with acute iv nicotine treatment (3 mg/kg body weight).
Results No significant differences in microvascular thrombus formation were detected after chronic nicotine application in male and
female animals when compared with controls. Accordingly, flow cytometric analysis did not show significant effects on platelet
activity. Chronic nicotine treatment resulted in a significantly reduced endothelial activation in male, but not in female
mice. In contrast, acute iv application of nicotine revealed significantly shorter thrombosis times in arterioles of female
mice and a significantly increased endothelial P-selectin expression in mice of both genders.
Conclusion Chronic nicotine application does not promote microvascular thrombus formation in mice of either gender, whereas acute high-dose
iv administration caused a significant increase of arteriolar thrombosis in female animals probably via a synergistic effect of increased endothelial P-selectin expression and female hormone levels. A gender-dependency of acute nicotine action can be presumed.
Best abstracts — Surgical Forum 2007 相似文献
999.
1000.
Changes in extracellular potassium concentration as measured with ion-selective microelectrodes revealed abnormally large accumulations in the hippocampus during postnatal development. While rises in [K+]o during stimulation of the Schaffer collaterals were limited to about 12 mM in adult animals, identical stimulations elicited rises to levels as large as 18 mM in juveniles. Since astrocytes are believed to play an important role in K+ homeostasis, we studied the postnatal development of astrocytes in the CA1 region of rat hippocampus in four age groups using a polyclonal antibody against glial fibrillary acidic protein (GFAP). The main proliferation of GFAP-positive cells (GFAPpc) occurred in all laminae between postnatal days 8 and 16. The number of GFAP-positive astrocytes per unit area was reached in stratum lacunosum-moleculare and stratum oriens at about 2 weeks and in stratum radiatum at about 3 weeks of age. During further development—at the age of 24 days—the orientation of individual astrocytes in stratum radiatum became polar with an orientation almost perpendicular to stratum pyramidale. This was revealed by an analysis based on determination of the quotients between the angular orientation of the processes of single individual GFAP-positive cells. When the crossing points of all glial processes over vertical and horizontal grid lines were determined and respective quotients evaluated, the same development towards a perpendicular orientation of astrocytes was noted in stratum radiatum. The same approach revealed a transient orientation parallel to the fissure in stratum lacunosum-moleculare around day 24. Camera lucida drawings of GFAPpc in stratum radiatum revealed that astrocytes became larger during the first three postnatal weeks, followed by a reduction of various parameters (e.g., cell extension, branching pattern) until adulthood. The observed developmental changes of astroglial cells may contribute to the known delayed maturation of potassium regulation in rat hippocampus. 相似文献