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Ohne ZusammenfassungMit 24 Textabbildungen.Vorgetragen: 1. I. Hausser, Ultraschall-Arbeitstagung Erlangen, 3. 5. 49; s. Kongreßbericht. 2. W. Doerr, ebendort; infolge Erkrankung vertreten durch I. Hausser. 3. R. Frey, Deutscher Chirurgenkongreß in Frankfurt, 9. 6. 49.  相似文献   
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Zusammenfassung An einem genealogisch zusammenhängenden Menschenmaterial von über 100 Personen wurde bis jetzt an 55 ein streng dominant erbliches, von Geburt an bestehendes Kinnmuskelzittern nachgewiesen.Bei vielen Trägern dieses Merkmals ist dieses mit gewissen bahnenden Tätigkeiten verknüpft, denen ein gemeinsamer spezifischer Gemütszustand (Achtsamkeit) innezuwohnen scheint, zu dessen Darstellung das Phänomen unter Umständen dienen könnte.Verf. sieht in dieser Verknüpfung eine Verwandtschaft des Phänomens mit den Affektäußerungen und mimischen Ausdrucksbewegungen des Menschen.Nach einem am 28. III. 1930 in der Wiener Gesellschaft der Ärzte gehaltenen Vortrage, wobei sieben Träger des Phänomens (Nr. 26, 28, 31, 34, 47, 50 und 52 des Stammbaums) vorgeführt wurden.Das Geburtsjahr wurde darum überall mitangeführt, weil es eine Hypothese, die sog. H. Swobodasche Siebenjahrlehre gibt, die den Einfluß eines Zeitfaktors in Form einer meist siebenjährigen Periodizität auf das erbliche Geschehen behauptet. Wie man sieht, könnte mau bei weniger ausführlichem Studium durch einige Beispiele (3, 11, 40!) versucht sein, auch aus dem vorliegenden Stammbaum ein solches Gesetz zu konstruieren. Genauerer Hinblick gibt aber schlagende Gegenbeispiele. Denn wie will H. Swoboda das unmittelbare Alternieren von Merkmalträgern und Merkmalfreien mit seiner Theorie in Einklang bringen? Z. B. Franz Sch. (4) ist tatsächlich 21, also dreimal sieben Jahre nach seiner Mutter Barbara (2) geboren. Der Einfluß dieses Siebenjahres muß nun aber schon im nächsten Jahr nach Swoboda erloschen sein, da ja der 1847 geborene Josef das KMZ. nicht bekam. Dann müßte aber das nächste Siebenjahr (1853) einen viel breiteren Einflußbereich (volle 5 Jahre) gehabt haben, da ihm sowohl Johanna (1850) wie Anton (1855) ihr KMZ. verdanken sollten. Das nächste Siebenjahr aber blieb überhaupt wirkungslos, denn Josefa (1860) ist frei von KMZ. Nun, was für das eine Siebenjahr recht ist, muß für das andere billig sein. Dies nur ein Beispiel für viele, das genugsam zeigt, wie trügerisch solches Spiel mit Zahlen ist. Und es ist immerhin bedenklich, wenn eine Lehre, die sich bis zu eugenetisehen Ratschlägen an hereditär belastete Eltern versteigt (!), an einem Erbmerkmal von so ungeheurer Durchschlagskraft, wie es das hier besprochene ist, ihre Gültigkeit nicht zeigen kann.  相似文献   
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After reduction of a disulfide bond at or near the mu opioid binding site in rat brain membranes, incubating membranes with 14 beta-bromoacetamido derivatives of either morphine, dihydromorphine, morphinone, or dihydromorphinone resulted in the irreversible inhibition of mu opioid binding to rat brain membranes. Without the addition of the disulfide bond-reducing reagent dithiothreitol, these affinity ligands bound reversibly to opioid binding sites. Binding to either delta or kappa opioid binding sites was not altered by alkylation of the membranes with the affinity ligands. The percentage of irreversible inhibition of mu opioid binding was dependent on the time and temperature of the incubation of membranes with the affinity ligands and on the concentrations of dithiothreitol and the affinity ligands. Incubating membranes with morphine afforded almost complete protection from alkylation of the mu opioid binding site. Naloxone and the l-isomer levorphanol also protected the site from alkylation, whereas the d-isomer dextrorphan and the kappa-selective opioid U50,488H did not protect the site. The mu-selective peptide [D-Ala2, (Me)Phe4,Gly(ol)5]enkephalin was the peptide that afforded the greatest protection. These studies have shown that, after the reduction of a disulfide bond at or near the mu opioid binding site, this sulfhydryl group can be specifically alkylated, resulting in the affinity labeling of the mu opioid binding site.  相似文献   
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The relationship between ageing and nutrition is considered with collagen as the intermediate target. Some data showed that diet restriction resulted in decreased collagen accumulation and collagen ageing. Conversely, being overweight reduced the lifespan and increased collagen ageing. Collagen ageing, which includes low turnover and glycoxidation, involves an increase in both stiffness and weakness. Their consequences concern all tissues including those with vital importance such as cartilage, heart ventricle or arterial wall.  相似文献   
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High-frequency respiratory impedance data measured noninvasively by the high-speed interrupter technique (HIT), particularly the first antiresonance frequency (f(ar,1)), is related to airway wall mechanics. The aim of this study was to evaluate the feasibility and repeatability of HIT in unsedated pre-term infants, and to compare values of f(ar,1) from 18 pre-term (post-conceptional age 32-37 weeks, weight 1,730-2,910 g) and 18 full-term infants (42-47 weeks, 3,920-5,340 g). Among the pre-term infants, there was good short-term repeatability of f(ar,1) within a single sleep epoch (mean (sd) coefficient of variance: 8 (1.7)%), but 95% limits of agreement for repeated measures of f(ar,1) after 3-8 h were relatively wide (-41 Hz; 37 Hz). f(ar,1) was significantly lower in pre-term infants (199 versus 257 Hz), indicating that wave propagation characteristics in pre-term airways are different from those of full-term infants. The present authors suggest that this is consistent with developmental differences in airway wall structure and compliance, including the influence of the surrounding tissue. Since flow limitation is determined by wave propagation velocity and airway cross-sectional area, it was hypothesised that the physical ability of the airways to carry large flows is fundamentally different in pre-term than in full-term infants.  相似文献   
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OBJECTIVE: For chemosensory event-related potentials (ERP) significant effects of age and sex have been demonstrated. The aim of the present study was to assess the effects of stimulus concentration, side of stimulation, and sex on the topographical distribution of chemosensory ERP in a large group of subjects stratified for different age groups. In addition, psychophysical measures of both olfactory and trigeminal function should be assessed in greater detail compared to previous work. METHODS: A total of 95 healthy subjects participated in the study. Olfactory functions were tested using the 'Sniffin' Sticks' comprising tests of odor identification, odor discrimination, and odor threshold. Trigeminal sensitivity was assessed on a psychophysical level using a lateralization paradigm. ERP to the olfactory stimulant H2S and the trigeminal irritant CO2 were recorded; stimuli were presented in different concentrations to the left and right nostril. RESULTS: Olfactory thresholds exhibited an age-related increase while the outcome of psychophysical trigeminal tests was not significantly affected by age. In contrast, there was no significant main effect of the factor 'sex' for olfactory tests, while women scored higher than men in the trigeminal task. ERP to olfactory and trigeminal stimuli exhibited a relationship to stimulus concentration, age, and sex with youngest women showing largest amplitudes and shortest latencies. There was no significant main effect of left- or right-sided stimulation on ERP. Measures of olfactory function were found to correlate with parameters of olfactory ERP even when controlling for the subject's age. In addition, correlations between scores in the lateralization task and parameters of the trigeminal ERP were found. CONCLUSIONS: Based on electrophysiological data obtained in a large sample size the present results established an age-related loss of olfactory and trigeminal function, which appears to be almost linear. Further, the present results emphasize that responses to chemosensory stimuli are related to sex, while the side of stimulation does not play a major role in the presently used paradigm. Finally, these data establish the lateralization paradigm as a psychophysical tool to investigate intranasal trigeminal function. SIGNIFICANCE: The present results obtained in a representative group of healthy subjects establishes a comprehensive set of data, which will serve as reference for future work in this area of research.  相似文献   
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BACKGROUND: Reactive oxygen species play a major role in the development of endothelial dysfunction. It is as yet unspecified whether increased oxidative stress contributes to endothelial dysfunction of the renal vasculature in patients with type 2 diabetes. METHODS: Renal haemodynamics were studied in 20 patients with type 2 diabetes and arterial hypertension (age 62 +/- 5 years) and 20 non-diabetic hypertensive patients at baseline and following infusions of the nitric oxide synthase inhibitor, N(G)-monomethyl-L-arginine (L-NMMA; 4.25 mg/kg); the substrate of nitric oxide synthase, L-arginine (100 mg/kg); and the antioxidant, vitamin C (3 g, co-infused with L-arginine 100 mg/kg). RESULTS: The response of renal plasma flow (RPF) to L-NMMA (-54 +/- 62 and -45 +/- 42 ml/min/1.73 m(2); P = NS) and L-arginine (+46 +/- 36 and +49 +/- 25 ml/min/1.73 m(2); P = NS) was not different between diabetic and non-diabetic patients. In contrast, vitamin C induced a more pronounced increase in RPF in diabetic than in non-diabetic patients when co-infused with L-arginine (+71+/-47 and +43+/-33 ml/min/1.73 m(2); P<0.05). CONCLUSIONS: The difference in the response of renal perfusion to an antioxidant suggests increased formation of reactive oxygen species and thereby reduced nitric oxide bioavailability in the renal vasculature of patients with type 2 diabetes.  相似文献   
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