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21.
Zusammenfassung Bei einem 21 jähr. Studenten, der zur Zeit einer Grippeepidemie eine Influenza durchgemacht hatte, traten 2 Wochen darauf zuerst kompletter Block mit Ohnmachtsanfällen, später nach Wiederherstellung der normalen Schlagfolge Störungen der Reizbildung und insbesondere der Reizausbreitung sowohl im Vorhof als auch in besonders ausgedehntem Maße innerhalb der Kammer auf, die auf eine diffuse Erkrankung des spezifischen Muskelsystems hinwiesen. Gleichzeitig bestanden Oppressionsgefühl auf der Brust, Mattigkeit, vorübergehend geringe Temperatursteigerungen. Alle diese Symptome werden als Grippe-Myokarditis gedeutet. Besonders wertvoll für die Erkennung dieses und ähnlicher Krankheitsbilder erweist sich die elektrokardiographische Untersuchung, die auch beim Fehlen anderer auf die Myokardaffektion bezüglichen Symptome, insbesondere auch von Arhythmien, durch den Nachweis von Störungen der Erregungsausbreitung in Vorhof oder Kammer Aufklärung über das Bestehen eines pathologischen Prozesses im Myokard zu geben vermag. Die frühzeitige Erkennung dieses Krankheitszustandes ist aber mit Rücksicht auf die notwendigen prophylaktischen Maßnahmen von großer Wichtigkeit.  相似文献   
22.
Zusammenfassung Die cytostatische Wirkung des Sanamycin auf Milz, Thymus und Nebennieren des Kaninchens wurde mit Hilfe einer vergleichenden cyto-histologischen Untersuchungtechnik geprüft, um einen näheren Einblick in die zellspezifischen Angriffspunkte des Medikamentes zu gewinnen. Der Effekt auf die normale Lymphopoese besteht in einer zeitlich begrenzten Abnahme der reifen Lymphocyten zugunsten einer Vermehrung der Lymphoblasten, wobei histologisch eine allgemeine Reduktion der lymphatischen Gewebsanteile in Erscheinung tritt. Das RHS bleibt in diesem Zusammenhang unberührt. Die Nebennieren zeigen nach hohen Sanamycindosen Veränderungen, die einer beträchtlichen Stresswirkung oder einer reversiblen toxischen Schäidgung entsprechen können. Das durch kurzfristige Sensibilisierung stimulierte Zellsubstrat der Antikörperbildung erfährt durch Sanamycingaben eine nachhaltige Depression, während dieser Effekt bei chronisch sensibilisierten Tieren wesentlich geringer ausgeprägt ist. Die tierexperimentell erhobenen Befunde werden im Hinblick auf die therapeutische Sanamycinwirkung bei lymphatischen Systemkrankheiten und die Möglichkeiteiner Beeinflussungakuter Antigen-Antikörperreaktionen diskutiert.Herrn Professor Dr.R. Schoen zum 65. Geburtstag.  相似文献   
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24.
The extent of human T-cell lymphotropic retorvirus HTLV-I and HTLV-II infections in the general population in central Europe has not been investigated fully. Two hundred forty-eight thousand blood donors from southern Germany were examined serologically for antibodies to the human lymphotropic retroviruses HTLV-I and HTLV-II: 0.021% were confirmed postive and 0.056% were “indeterminate”. A limited number of seropositives and “indeterminate” samples were analyzed by polymerase chain reaction (PCR): the seropositives were confirmed as positive and 43% of the “indeterminate” samples were PCR-positive. The range of 0.021% HTLV-positives in 248,000 donors, i.e. about two in 10,000 individuals, mirrors closely the published data for the United States. © 1994 Wiley-Liss, Inc.  相似文献   
25.
Female heterozygotes of the fra(X) form of mental retardation show variable degrees of mental impairment and phenotype expression of the disorder. This might be an effect of inactivation of the X-chromosome which carries the fra(X)(q). Prior replication studies in heterozygous carriers gave contradictory results with respect to possible genotype-phenotype correlation. In the interpretation of these studies it is important to understand the effect of BrdU on the fra(X)(q) expression. In a group of 13 hemizygous patients with fra(X)(q) and 7 heterozygous carriers we studied the effect of BrdU on fra(X) expression. In the heterozygous carriers the use of BrdU resulted in a significant suppression of the fra(X)(q), while in hemizygous patients no difference in fra(X)(q) frequency with or without BrdU could be observed. It can be concluded that BrdU suppresses the fra(X)(q) preferentially on the inactive X-chromosome. Thus the fra(X)(q) frequency on the active X-chromosome is of primary importance in phenotype correlation studies among heterozygous carriers. In our group of heterozygous carriers we observed a negative correlation between (IQ) phenotype and fra(X)(q) expression on the active X-chromosome. This suggests that the gene for the fra(X)(q) form of mental retardation is on the X-chromosome and undergoes inactivation.  相似文献   
26.
In the peritoneal cavity of the adult rat mast cells at the four stages of progressive maturation (and corresponding increase of sulphation of granules) are best demonstrated in free peritoneal fluid. Of the 0.1-0.2x10(6) cells in the free fluid, 26% are at stage 1 of maturation (all granules are stained by Alcian blue). 24% at stage 2 (majority of granules are stained by Alcian blue, minority by safranin), 20% at stage 3 (majority of granules are safranin-positive), and 30% at stage 4 (all granules are safranin-positive). Peritoneal washings yield a mean of about 1.3-1.8x10(6) mast cells of which 16% are at stage 1, 24% at stage 2, 34% at stage 3 and 26% at stage 4. The greater number recovered by washing, compared with the number in free peritoneal fluid, suggests that a substantial number of mast cells lie on the surface of the peritoneal membranes.  相似文献   
27.
The responses of tendon organs of the anterior tibial muscle have been studied during twitch contraction, passive stretch, fused tetanic contractions and sinusoidal stretching in Nembutal anesthetized cats. The majority of the tendon organs had similar thresholds to active contraction and passive stretch tension. Some tendon organs were found to discharge spontaneously in the relaxed muscle. An approximate power function relationship has been found between steady state impulse frequency and muscle tension. The receptor properties are compared with those of soleus tendon organs. It is concluded that static and dynamic properties of Golgi tendon organs in the anterior tibial and the soleus muscles fall within the same range of variation, and that apparent discharge dissimilarities can be explained as due to differences in muscle mechanics.  相似文献   
28.
Poorly differentiated neuroendocrine cells can be difficult to recognise. Sensitive methods are needed to label cells that have lost their ultrastructural features and have reduced concentrations of neuroendocrine markers. In gastric neoplasms, enterochromaffin-like cells might dedifferentiate and lose their characteristic granules and secretory vesicles, making detection of such cells increasingly difficult. However, chromogranin A (CgA) immunogold labelling could provide sensitive and specific detection of gastric neuroendocrine cells. We present ultrastructural findings, CgA immunogold labelling as well as conventional immunohistochemical findings of two human enterochromaffin-like cell carcinoids. Electron-dense granules of poorly differentiated cells were less intensely labelled than granules in well-differentiated cells. Granules with atypical shape as well as punctuate granules previously found in neuroendocrine neoplasms were also CgA labelled. The CgA labelling efficacy after antigen retrieval in an alkaline solution was higher after heating in an autoclave at 135 degrees C compared to a microwave at 100 degrees C for both granules and secretory vesicles without significant deterioration of the ultrastructure. In conclusion, the use of CgA immunogold labelling could ensure a specific classification of cells with neuroendocrine granules and be a supplement to immunohistochemical examination of poorly differentiated tumours.  相似文献   
29.
In supplementation of previously published cardiac sodium channel (SCN5A) gene mutations that were cited in the text, in Table 2 and in Figure 2 we here apply an updated gene mutation nomenclature (Human Genome Variation Society, 2005) to facilitate mutation annotation comparison (SCN5A cDNA reference: NM_198056.1 or GI: 37622906; amino acid reference sequence: SWISS‐PROT entry Q14524, long splice variant, 2,016 amino acids): Mutation: c.2602delC Amino acid change: p.Glu868X Mutation: c.2581_2582delTT Amino acid change: p.Phe861Trp fsX90 Mutation: c.4477_4479delAAG Amino acid change: p.Lys1493del Mutation: c.5425C>A Amino acid change: p.Ser1812X  相似文献   
30.
Measurements of the surface tension of articular cartilage and friction experiments were carried out to provide further evidence in support of a new theory regarding the mechanism of friction in joints. To determine the surface tension of cartilage, contact angle measurements were used in conjunction with the equation of state for interfacial tensions. The advancing contact angle between saline drops and articular cartilage was found to be 100°±5°, indicating a highly hydrophobic surface. The corresponding surface tension value was calculated to be 22.5 ergs/cm2. Friction of cartilage against hydrophobic surfaces is shown to be lower than the friction of cartilage against hydrophilic surfaces. All these results further support the theory that lubrication by nonwetting drops occurs in joints and may be responsible for the exceptional friction characteristics of the joints.  相似文献   
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