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61.
Erdheim-Chester disease (ECD) is a rare disorder that has been reported fewer than 60 times in the literature. Although clinical findings seem to be specific at first sight, histologic classification remains unclear. It has not been decided whether ECD is part of the spectrum of histiocytoses or whether it may be a lipid storage disorder or even a primary macrophage cell disorder, although it does show a distinct histologic pattern. However, the clinical appearance alone shows several typical features, rendering the diagnosis very probable if present. This article illustrates the importance of bone scanning in ECD, because the scintigraphic pattern of involved skeletal sites may in themselves lead to the diagnosis. Several differential diagnoses are considered. The importance of bone scintigraphy as an imaging method in patients with an unclear diagnosis is discussed, as exemplary in ECD, as is its role for the detection of sites of skeletal involvement in other diseases.  相似文献   
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In longitudinal muscle/myenteric plexus preparations of the guinea-pig ileum, exogenous nitric oxide (NO) induced concentration-dependent relaxations. In tissues at basal tone, NO (3 × 10–6 M) induced a moderate relaxation followed by a pronounced contraction, consisting of a quick and sustained component. Tetrodotoxin (5 × 10–7 M) abolished both phases of the contraction. Atropine (5 × 10–7 M) abolished the quick component and reduced the sustained component of the contraction; the latter was further suppressed by the selective NK1 receptor antagonist CP 96,345. Hexamethonium (5 × 10–5 M) failed to affect the contractile response to NO. It is concluded that administration of exogenous NO in the guinea-pig ileum can lead to activation cholinergic and to a lesser degree tachykininergic neurones. Correspondence to: L. Barthó at the above address  相似文献   
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Oocyte donors are chosen among phenotypically normal and fertile women who are not expected to carry any chromosomal abnormality. A high incidence of balanced structural chromosomal rearrangements has been found within oocyte donors. This result raises the question of a possible bias in their recruitment with respect to their familial background and/or personal reproductive history.  相似文献   
65.
Polycystic ovary syndrome (PCOS), insulin resistance and overall mortality due to diabetes and coronary artery disease are higher in South Asians than in Caucasians. Aims: We compared the prevalence of the C677T and A1298C single nucleotide polymorphisms in the methylenetetrahydrofolate reductase gene in South Asian and Caucasian women, its association with folate and homocysteine (Hcy) metabolism, and its relevance to future atherogenic events. Methods and results: 71 women were recruited for the study: South Asian PCOS (21) plus controls (9) and Caucasian PCOS (25) plus controls (16). Anthropometric and laboratory parameters were compared. South Asian PCOS women were significantly hyperandrogenic and exhibited a greater degree of insulin resistance. Caucasian PCOS women had higher plasma Hcy concentrations with a 1.9 times higher frequency of the T allele than the South Asian PCOS group. In the presence of this variant allele, plasma Hcy levels appear to be higher in both PCOS groups. The South Asians had a 1.8 times higher frequency of the C allele than the Caucasians; however, the overall frequency was comparable in the two PCOS groups. The frequency of homozygosity, i.e. TT677 and CC1298, was 7.2% and 4.9% in the Caucasians and 0% and 16.6% in the South Asian recruits, respectively. Dietary inadequacies in the South Asian women can influence their plasma folate and B12 concentrations resulting in hyperhomocysteinemia which, in combination with dyslipidaemia and insulin resistance, can lead to long-term atherogenic consequences. CONCLUSIONS: Current data suggests that the mechanisms of atherothrombosis have separate pathways in the two ethnic groups. Larger studies exploring the current theme need to be carried out in the PCOS groups to obtain adequate insight.  相似文献   
66.
Zusammenfassung Es wird über Untersuchungen des Nucleinsäurestoffwechsels am Ehrlich-Ascitescarcinom der Maus berichtet, in denen eine weitgehend parallele Hemmung der RNS- und der DNS-Synthese durch Trenimon gefunden wurde. Es dürfte sich bei den beobachteten Hemmeffekten um Hemmungen der jeweiligen Nucleinsäure-Polymerasereaktionen handeln. Als Ursache für die gestörten Polymerasereaktionen wird eine Reaktion von Trenimon mit der DNS vermutet.
Summary Studies of the nucleic acid metabolism of mouse Ehrlich ascites carcinoma cells are reported. It was found that the inhibition of the RNA and DNA synthesis, caused by the cytotoxic ethylenimine derivative, Trenimon, paralleled one another. It is assumed, that the observed inhibitions are at the level of the nucleic acid polymerase reactions, and that the effects are due to a reaction of Trenimon with DNA.


Mit 7 Textabbildungen

Dem Andenken unseres verstorbenen Lehrers, Herrn Prof. Dr. med. G. Schubert gewidmet.

Die Untersuchungen wurden mit Unterstützung der Deutschen Forschungsgemeinschaft und des Bundesministeriums für Wissenschaftliche Forschung durchgeführt.

Der Robert-Koch-Stiftung e.V. sei für die Anschaffung eines Rotors Typ 40 zur Spinco-Ultrazentrifuge gedankt.  相似文献   
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Interactions between environmental and biological factors affect the vector competence of Culex pipiens quinquefasciatus for West Nile virus. Three age cohorts from two Cx. p. quinquefasciatus colonies were fed blood containing a low- or high-virus dose, and each group was held at two different extrinsic incubation temperatures (EIT) for 13 days. The colonies differed in the way that they responded to the effects of the environment on vector competence. The effects of mosquito age on aspects of vector competence were dependent on the EIT and dose, and they changed depending on the colony. Complex interactions must be considered in laboratory studies of vector competence, because the extent of the genetic and environmental variation controlling vector competence in nature is largely unknown. Differences in the environmental (EIT and dose) and biological (mosquito age and colony) effects from previous studies of Cx. p. quinquefasciatus vector competence for St. Louis encephalitis virus are discussed.  相似文献   
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