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1.
Ohne ZusammenfassungMit 3 TextabbildungenHerrn Prof. Dr. A. Hase in Verehrung gewidmet.  相似文献   
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Ohne ZusammenfassungMit 7 Textabbildungen.  相似文献   
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Concurrent infections with two parasites: a nematode,Trichinella spiralis, and a protozoon,Toxoplasma gondii, were investigated. Antibody production (total immunoglobulin and IgM) was similar in double and single infections. However, the number ofToxoplasma cysts in the brains of mice infected withTrichinella and challenged 1–6 weeks later withToxoplasma was higher than in mice infected withToxoplasma alone, while mice infected withToxoplasma and challenged 4–14 days later withTrichinella had lower worm burdens in the intestine than animals infected withTrichinella alone. Greater loss in body weight was observed in mice infected with both parasites than in those infected with either parasite alone.  相似文献   
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Clinical Rheumatology - Bone sarcoidosis is usually rare. Imaging procedures such as fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) can reveal bone...  相似文献   
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Background According to the concept of sentinel node (SN), the lymphatic pathway leading to SN should be regarded as the main and the most important lymphatic route from primary tumor to regional lymph nodes. We performed ex vivo blue-dye SN mapping in postmastectomy specimens to assess whether the main lymphatic tract leading to SN is completely removed during mastectomy. We assumed that ex vivo identification of SN may be possible only if the entire lymphatic tract leading to sentinel node is removed from within the postmastectomy specimen. Methods Blue dye (1 mL) was injected intracutaenously, periareolary into each of 28 postmastectomy specimens. In 13 cases mastectomy was performed with the use of transverse skin incision; in 15 cases oblique incision was used. Results The use of transverse skin incision during modified radical mastectomy allowed identification of the sentinel node and removal of the entire lymphatic pathway leading to sentinel node only in 4 of 15 cases (31%). Conversely, the use of oblique skin incision during modified radical mastectomy allowed identification of the sentinel node and removal of the entire lymphatic pathway leading to sentinel node in 12 of 15 cases (80%). Conclusions Our experiment revealed that the use of transverse skin incision during modified radical mastectomy may not be the best choice for breast cancer patients. In our opinion, this observation may be especially important for patients not irradiated postoperatively.  相似文献   
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Zusammenfassung Die Ausbildung der Mikrogameten bei T. gondii beginnt mit einer Vervielfachung des Gamontenzellkerns. In der Oberfläche des Gamonten treten nacheinander mehrere Vorwölbungen auf, denen sich jeweils ein Zellkern zuordnet. In den Vorwölbungen bilden sich die späteren Perforatorien der Mikrogameten aus, und es werden— ausgehend von je einem Basalkörper — 2 Geißeln gebildet. Der Mikrogamet wächst jetzt gleichsam aus der Oberfläche des Gamonten heraus. Hierbei tritt das große Mitochondrium in engen Kontakt mit dem Zellkern. Der Zellkern streckt sich, und nach Durchtrennung einer letzten Plasmaverbindung liegen die Mikrogameten frei in der parasitophoren Vakuole.Aufgrund verschiedener Bilder sind wir der Auffassung, daß die Mikrogameten von T. gondii — im Gegensatz zu denen anderer Coccidienarten (z. B. E. pragensis, E. nieschulzi, E. perforans) — nicht gleichzeitig, sondern in Gruppen nacheinander entstehen. Es bleibt ein Restkörper zurück. Der Mikrogamet von T. gondii ist, durch die Gestalt des Zellkerns verursacht, sehr breit und stark abgeflacht. Das Mitochondrium ist vom tubulären Typ; die Tubuli liegen nicht in Reihen, sondern ungeordnet im Mitochondrium. Neben den 2 Geißeln lassen sich Reste einer rudimentären dritten erkennen. Im Perforatorium sind 16 oder mehr sehr kurze Mikrotubuli in einer Reihe, dicht oberhalb einer stark osmiophilen Platte angelegt. Ihre Funktion ist zur Zeit noch nicht geklärt.
Electron microscopical studies on the microgametogeny of Toxoplasma gondii
Summary The micorgametogony of T. gondii is investigated electronmicroscopically. The formation of the gametes begins with a multiplication of the gametocyte nucleus. The surface of the gametocyte develops many protuberances and a single cell nucleus migrates into each. Within the protuberances later to become the perforatoria of the microgamete, two flagella develop from each basal body. The protuberance then grows and buds off to form the microgamete. During this process the large mitochondrion migrates into closer contact with the nucleus. The nucleus elongates and when the last plasma connection is severed the microgamete lies free in the vacuole surrounding the parasite.On the bases of the different structures observed, we suppose that the microgametes of T. gondii develop in groups, one after the other, in contrast to other Coccidia, e.g. E. pragensis, E. nieschulzi, E. perforans where they develop simultaneously. In T. gondii a residual body remains and, because of the form of the nucleus, the microgamete is wide and flat. The mitochondrion is of the tubular type; the tubules ramifying rather than lying in rows. Next to the two flagella rudimentary remains of a third can be found. In the perforatorium 16 or more very short microtubuli lie packed together on top of a strongly osmophilic plate but their function has not yet been determined.
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8.
A case of a 54 year old female with cor tritriatum is described. Diagnostic role of transthoracic and transesophageal echocardiography is discussed.  相似文献   
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The twin-reversed arterial perfusion (TRAP) sequence and development of an acardius are rare and severe complications in monozygotic twin pregnancy. Haemodynamic disturbances in placental perfusion via abnormal vascular anastomoses allow inter-twin transfusion to occur. Because of blood perfusion, one of the twins is poorly oxygenated and contains metabolic waste products. Retrograde placental perfusion leads to the formation of a non-viable malformed acardiac foetus. We studied the effects of haemodynamic disturbances in acardiac foetus on the development of the nervous system. The acardius was a product of a 32-weeks pregnancy. Caesarean section yielded a skin covered ovoid mass (size, 10 x 8 cm; weight, 220 g). The dissection of the acardiac twin showed a skin with hair and appendages, rudimentary lower limbs, vertebral column and brain mass. The rudimentary brain tissue was considerably disorganised structurally. We distinguished two main morphological forms of various appearances. In the centre, we observed a scarcely vascularised mass of tissue containing mature and immature neurones, glial cells and randomly distributed fibres. The mass of tissue appeared poorly differentiated, although there were some arrangements reminiscent of cerebral structures. Clusters of neurones provided a slight suggestion of nuclear or fibre structure. The cerebellar cortex was the only well recognisable structure. In the other fragment of the tissue, we found a slit cavity with ependymal outline and well-developed choroid plexus, which seemed to represent the 3rd ventricle. The scarcely vascularised disorganised tissue was surrounded by the highly vascularised one. It included many thin-walled sinusoid vessels. In some places, they were so concentrated that they resembled cavernous haemangioma. The spinal cord appeared comparatively well organised with a slightly dilated central canal. The morphological picture of the rudimentary brain tissue was similar to the picture of the cerebrovasculosa area. The effect of ischaemia in the presented case is the anomalous formation of the cerebral structures. The morphological features imply that the failure occurred after neurulation and before the prosencephalic began to grow. The failure of neural tube formation occurred on the 22nd-25th day of gestation. The malformed formation of the nervous system might be caused by impaired induction due to altered gene expression or to the interference of exogenous agents that interrupt normal development. The haemodynamic abnormal placental circulation, which induced lack of oxygen supply and nutritional deficiency, implies the morphological pattern of the anomaly.  相似文献   
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