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21.
The umbilical vascular bed of the rat placenta was perfused in situ. Ouabain (10–4M) in the perfusion fluid had no effect on the unidirectional flux of Na+ from the maternal (electrically negative) to the foetal (electrically positive) side of the placenta, or on the transplacental potential difference. This was taken to indicate that there is no significant active transport of Na+ across the placenta of the rat. 相似文献
22.
Sexual dimorphism (SD) represents all the differences between males and females of the same species. SD of the murine lacrimal gland and the major effect of testosterone on its formation are well documented. Steroidogenic factor-1 (SF-1, NR5a1) is a nuclear receptor essential for the fetal development of steroid hormones producing organs and SF-1 knockout mice (Sf-1 KO) are therefore born without gonads and adrenal glands. The aim of this study was to investigate whether SD in lacrimal glands is present in the absence of exposure to sex hormones during development. Lacrimal glands from adult Sf-1 KO male and female mice without hormonal exposure, and from males that were treated with testosterone propionate (TP) prior to sacrifice, were examined. After sacrifice, glandular tissue was processed using standard histological procedures. Paraffin sections were analysed by stereology and immunostained against the androgen receptor (AR). Our results showed that there were no statistically significant differences in the mean volumes of acini, connective tissue or ductal system between males, females, and males on TP. The same pertains to the mean length of the ducts in all three groups. In the absence of sex hormones, sex chromosomes proved to be insufficient in inducing sexual dimorphism in LG. However, nuclei of the acinar cells in males on TP were positive for AR, whereas in males without TP no expression of AR was detected. Administration of TP induced the expression of AR in the nuclei of acinar cells of males but did not affect the morphology of LG. We conclude that SD in the lacrimal gland is not present in Sf-1 KO mice and this suggests that sex hormones have a major role in the development of SD in the lacrimal gland. 相似文献
23.
Ein Vergleich der Glucose-, Ketonkörper- und Glycerinspiegel im Nabelschnurblut und im Placentarblut
V. Šabata S. Lausmann H. Wolf 《Journal of molecular medicine (Berlin, Germany)》1968,46(24):1317-1318
Zusammenfassung 1. Die Bestimmung von Ketonkörpern, Glucose und Glycerin getrennt in Nabelartcrie, Nabelvene, Placentararterie und Placentarvene ergab für Glycerin und Ketonkörper im Placentarblut meist etwas höhere Werte als im Nabelschnurblut.2. Es folgt daraus, daß es nicht zulässig ist, aus experimentellen Gründen Placentarblut an Stelle von Nabelschnurblut zu verwenden.3. Durch die Analyse der möglichen Ursachen kamen wir zu dem Schluß, daß es sich bei diesen Veränderungen wahrscheinlich um eine Widerspiegelung des placentaren Stoffwechsels handelt. Hämodynamische Einflüsse jedoch sind nicht auszuschließen.4. Es ist möglich, daß der Vergleich von Placentarblut und Nabelschnurblut unter normalen und pathologischen Bedingungen zum Studium des Stoffwechsels der Placenta in situ einen Beitrag liefern kann.
Herrn Prof. Dr.G. Joppich zum 65. Geburtstag gewidmet.
Die Arbeit wurde von der Deutschen Forschungsgemeinschaft unterstützt (Wo 69/7).
Stipendiat der Alexander von Humboldt-Stiftung, 1967/68. 相似文献
Summary 1. The separate determination of ketone bodies, glucose and glycerol in umbilical cord artery and vein, placental artery and vein resulted in elevated levels of glycerol and ketone bodies in placental blood compared to cord blood.2. It is concluded that for experimental purposes cord blood is not to be replaced by placental blood.3. In analysing the possible facts we drew the conclusion that these results indicate a representation of the placental metabolism. Hemodynamic factors were not to be excluded, however.4. The comparison of placental with cord blood under normal and pathological conditions will possibly add to the study of placental metabolism in situ.
Herrn Prof. Dr.G. Joppich zum 65. Geburtstag gewidmet.
Die Arbeit wurde von der Deutschen Forschungsgemeinschaft unterstützt (Wo 69/7).
Stipendiat der Alexander von Humboldt-Stiftung, 1967/68. 相似文献
24.
M. Deckert-Schlüter Josef Marek Michael Šetlík Jana Marková E. Pakos Robert Fischer Otmar D. Wiestler 《Virchows Archiv : an international journal of pathology》1998,432(5):477-481
A 62-year-old woman presented with loss of memory and a mild hemiparesis. Neuroradiology demonstrated a left frontoparietal
tumour. Biopsy specimens of this lesion revealed intracerebral Hodgkin’s lymphoma, a diagnosis supported by immunohistochemical
reactions of the tumour cells for the CD30 antigen. Additional cell cycle studies revealed a high proliferative activity of
the tumour cells in association with absence of apoptosis. There was no evidence that overexpression of bcl-2 or Epstein-Barr
virus infection was involved in the pathogenesis of this neoplasm. Lymphomas in the lung were detected 3 months later. Following
neurosurgical excision, radiotherapy, and chemotherapy, the patient had no evidence of Hodgkin’s disease after 13 months of
follow-up.
Received: 8 October 1997 / Accepted: 8 December 1997 相似文献
25.
Jiřina Bartůňková Ana Araujo Ondřej Hrušák Anna Šedivá 《Journal of clinical immunology》1997,17(6):455-461
Antineutrophil autoantibodies reacting with cytoplasmic antigens are associated with various types of vasculitides, whereas antibodies reacting with neutrophil membrane antigens are mostly related to autoimmune neutropenias. The aim of this study was the investigation of the effect of monoclonal antibodies (MoAbs) reacting with surface and cytoplasmic antigens of polymorphonuclear leukocytes (PMN) known to be targets for autoantibodies in human diseases. Blood of healthy volunteers was tested for several phagocytic functions in the presence of MoAbs against surface (CD16, GD11b, CD18, NB1) and cytoplasmic (proteinase 3; PR3) molecules. Candidacidal activity was significantly inhibited in the presence of all MoAbs but isotypic control. Phagocytic activity was inhibited by anti-CD11b and/or anti-CD18 MoAbs. Zymosan-induced chemiluminescence was reduced by MoAbs anti-CD16, CD18, and NB1, enhanced by anti-PR3 MoAb, and less enhanced by anti-CD11b. In conclusion, antimembrane antibodies diminished phagocytic functions at multiple steps; in contrast, anticytoplasmic MoAb promoted activation of oxidative burst in addition to impairment of microbicidal activity. This fact may be related to different pathogenic aspects of diseases associated with antimembrane and anticytoplasmic antibodies. 相似文献
26.
Dr. M. Elleder F. Šmíd K. Harzer J. Čihula 《Virchows Archiv : an international journal of pathology》1980,385(2):215-231
Summary The results of a complex analysis of liver tissue are presented (four biopsy and two autopsy samples) obtained from six patients with Niemann-Pick disease (NPD) with a gross deficiency of sphingomyelinase (SMase) accompanied by a typical increase in sphingomyelin (SM). There were five cases of NPD type A (four of them with an atypical, prolonged course) and one case of type B. By means of lipid histochemistry it was possible to demonstrate SM storage both in hepatocytes and in the reticuloendothelial system (RES) of the liver (Kupffer cells and portal macrophages) and to show in two siblings with NPD type A a so-far undescribed centrilobular storage pattern. Enzyme histochemistry revealed a secondary deficit of nonspecific esterase activity and acid -galactosidase in liver storage macrophages and varying degrees of suppression of hepatocytic enzyme activities as a reaction to lipid storage of sudden onset. Ultrastructurally, it was possible to demonstrate cholesterol in lysosomes by using digitonin fixation, the involvement of Ito cells in lipid storage, the aggregation of storage lysosomes with certain other organelles and their occasional connections with the endoplasmic reticulum. The problems of possible lipid extraction during processing were considered as a cause of pronounced lysosomal electron-lucidity and of the ultrastructural identification of the participating lipopigment. The significance of the findings is discussed in relation to the existing classification and, particularly, to the stored lipid dilemma of cases of NPD type C. 相似文献
27.
The coccidium Sarcocystis singaporensis (Apicomplexa: Sarcocystidae) is a cyst-forming parasite with potential as a biological agent for the control of wild populations of rodents in non-native environments. Phylogenetic analysis based on the ssrDNA supports S. singaporensisisolates as a sister species to sarcosporidians transmitted between snakes and rodents but an association with the carnivore-ruminant Sarcocystis spp. could not be rejected by likelihood ratio tests. Four complete and six partial ssrDNA sequences representing this species are monophyletic in any tree reconstruction method; however, they possess very high pairwise distances of up to 0.053. The obtained sequences suggest the probable existence of at least two divergent paralogous ssrDNAs. Moreover, our results support the co-evolution of lsrDNA and ssrDNA in S. singaporensis. The utility of coccidian lsrDNA and ssrDNA for evolutionary studies and their abundance in the primary nucleotide databases is discussed. 相似文献
28.
Summary During the period of three years (1972–1974), serum samples from 60 patients (children and adolescents) with lympho-hematopoietic system diseases were examined for antibodies to all four human herpesviruses. Among these were 26 active Hodgkin's disease (AHD) patients and 6 HD patients with a minimum five years' remission. Simultaneously matched controls (age, sex) of AHD patients were examined. Antibody levels against the viral capsid antigen of Epstein-Barr virus (EBV/VCA) in AHD patients were significantly higher, with overrepresentation of higher titres (1:160), than in matched controls. The lowest EBV/VCA antibody titres were in the leukemia-non-Hodgkin's lymphoma patients. We could not prove any significant relationship between cytomegalovirus or herpes simplex virus type 1 antibody titres and AHD or any other disease of lymphohematopoietic system. The varicella-zoster virus antibody titres in AHD patients were significantly higher than in matched controls. No significant differences in antibodies against EBV/VCA and the other human herpesviruses between the evolution and remission period of AHD patients could be detected. No differences in EBV/VCA antibody titres were observed between the healthy school-children aged 10 to 15 years who were and who were not in contact with a HD patient. 相似文献
29.
Špacírová Zuzana Epstein David Espín Jaime 《The European journal of health economics》2022,23(9):1563-1575
The European Journal of Health Economics - Economic evaluation of health technologies requires healthcare resources, procedures and services to be valued at their opportunity cost. In practice,... 相似文献
30.
Lucie Bryndová Michal Bar Roman Herzig Robert Mikulík Jiří Neumann Daniel Šaňák Ondřej Škoda David Školoudík Daniel Václavík Aleš Tomek 《Health policy (Amsterdam, Netherlands)》2021,125(4):520-525
This article describes policy processes that have led to the re-organisation of stroke care in the Czech Republic since 2011, which has been part of a broader process of care concentration in several medical fields. Currently, stroke care is provided by 13 Comprehensive and 32 Primary Stroke Centres. The paper explains factors that supported the reform implementation, reviews implications, and discusses future challenges.Mandatory reporting of quality indicators, the introduction of a benchmarking system, integration with pre-hospital emergency care, and the introduction of countrywide patient triage have supported more timely treatment for stroke patients and better quality of care. Data from the Stroke Care Quality Indicators of the Czech Stroke Society show positive trends in many areas: the number of patients treated with intravenous thrombolysis quadrupled in eight years, with 26.4 % of all acute stroke patients receiving thrombolysis in 2018. Czech Republic now ranks third in Europe in the number of thrombolysis per population and second in the number of mechanical thrombectomies per population. The Czech experience provides an example of positive outcomes of concentrated stroke care, while highlighting the importance of proper implementation processes. In particular, it is essential to involve stakeholders and to provide reputational incentives through continuous benchmarking. 相似文献