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81.
Ultrastruktur und Differenzierung der prostatoiden Organe von Polystyliphora filum (Plathelminthes,Proseriata) 总被引:1,自引:0,他引:1
J. Brüggemann 《Zoomorphology》1984,104(2):86-95
Zusammenfassung
Polystyliphora filum besitzt neben einem dem männlichen Begattungsorgan angeschlossenen Stilett eine Vielzahl gleichartiger prostatoider Organe, stets caudal des Begattungsorgans serial angeordnet. Jedes dieser prostatoiden Organe besteht aus einem Stilett, das in ein Atrium reicht, und einem caudal anschließenden Bulbus. Das Stilett hat die Form eines gebogenen Trichterrohres mit einem plattenförmigen Fortsatz in der Mitte; Trichterrohr und Fortsatz werden zusammen in einer einzelnen Zelle ausdifferenziert. In einer frühen Bildungsphase wird in der basalen Hälfte zunächst ein Gerüst aus Mikrotubuli angelegt, an das sich elektronendichtes Material anlagert. In einem späteren Bildungsstadium werden teilweise die Zwischenräume zwischen der entstehenden Hartstruktur und der Außenmembran der Bildungszelle mit elektronendichtem Material ausgefüllt. Die Spitze des Stiletts wird durch Anlagerung elektronendichten Materials an die Außenmembran gebildet. Die Differenzierung der gesamten Hartstruktur erfolgt simultan und intrazellulär. Gleichzeitig wird auch die gesamte Muskulatur des prostatoiden Organs ausgebildet. Die vollständig ausdifferenzierten prostatoiden Organe enthalten keine Spermien, sondern nur große Mengen eines grobscholligen Sekretes.
Abkürzungen am Atriummuskulatur - bl Basallamina - bm Bulbusmuskulatur - bmk Kernregion einer Bulbusmuskelzelle - bz Stilettbildungszelle - cw Cilienwurzel - ep Epidermis - fz Füllzelle - hz Hüllzelle - mv Mikrovilli - n Nerv - p Protraktor - pa Protraktoransatz - r ciliärer Rezeptor - s Stilett - sd Septatdesmosomen - sm Schließmuskel - sz Sekretzelleg 相似文献
Ultrastructure and differentiation of the prostatoid organs of Polystyliphora filum (Plathelminthes, Proseriata)
Summary In addition to a male copulatory organ containing a stylet, Polystyliphora filum has numerous uniform prostatoid organs which are arranged in series caudally to the copulatory organ. Each of these prostatoid organs consists of a stylet, extending into an atrium, and caudal to this a bulb. The stylet is funnel-shaped with a curved distal part and a flattened projection in the middle; funnel and projection are differentiated together in a single cell. In an early phase of differentiation, a framework of microtubules is built in the basal part, and this becomes enveloped by electron-dense material. In a later phase, the space between the formed hard structure and the outer membrane of the style building cell is partially filled up with electrondense material. The distal part of the stylet if formed by electron-dense material taken up to the outer membrane. The whole hard structure is differentiated simultaneously and intracellularly. At the same time the whole muscular system of the prostatoid organ is formed. The completed prostatoid organs do not contain sperm, but much coarsegrained medium electron-dense secretion.
Abkürzungen am Atriummuskulatur - bl Basallamina - bm Bulbusmuskulatur - bmk Kernregion einer Bulbusmuskelzelle - bz Stilettbildungszelle - cw Cilienwurzel - ep Epidermis - fz Füllzelle - hz Hüllzelle - mv Mikrovilli - n Nerv - p Protraktor - pa Protraktoransatz - r ciliärer Rezeptor - s Stilett - sd Septatdesmosomen - sm Schließmuskel - sz Sekretzelleg 相似文献
82.
Dr. T. S. Sætersdal R. Myklebust H. Engedal S. Ødegaarden 《Cell and tissue research》1978,186(1):13-24
Summary The substructure of the inner mitochondrial membranes has been studied by cryo-ultramicrotomy under conditions during which denaturation of proteins by treatment with chemical solutes has been totally avoided. In such preparations, the inner membrane has a substructure consisting of globular subunits. These subunits have an average diameter of ca. 20Å–ca. 62Å and are fairly regularly spaced. Intracristal space is absent in the unstained, freeze-dried preparations, whereas a space of ca 40Å is seen in preparations lightly treated by OsO4-vapour. It is concluded that the subunits of the inner mitochondrial membranes probably consist either of single protein molecules or of complexes of protein molecules.This work was supported by grants from The Norwegian Council on Cardiovascular Disease and from The Norwegian Research Council for Science and the Humanities 相似文献
83.
Crystal-containing organelles in cells of virus infected plants lying at chloroplasts and mitochondria are identical with single membrane-bound microbodies containing crystals of catalase described in healthy plants. Massive complex inclusions caused by turnip mosaic virus very frequently contain the same microbodies with crystal inclusions; that phenomenon may be related to some pathophysiological changes of virus infected plants. Comparable proteinaceous crystals, but not lying within microbodies limited by a membrane, may also be found in cytoplasm of infected cells. These crystals are sometimes surrounded by a substance resembling the microbody matrix. Disintegrated cytoplasm of virus infected cells may also contain the same crystals lying free in “empty spaces”. Cytopathological effects responsible for this phenomenon and possible artifacts as well are discussed. 相似文献
84.
A new diol glucoside, 2-β-d-glucopyranosyloxy-2-methylpropanol, the first reported naturally occurring monoglucoside of an aliphatic dihydric alcohol, was isolated from pods of Acacia sieberana var. woodii. Structure elucidation was based on 1 H and 13C NMR spectroscopy, and enzymatic analyses. The compound was hydrolysed very slowly by almond β-glucosidase, but cleaved by a β-glucuronidase enzyme complex from Helix pomatia. 相似文献
85.
The transport system for organic acids in the kidney is not fully developed in the neonatal period. The effect of repeated administrations of ethacrynic acid on the renal excretion of p-aminohippurate (PAH) was studied in rats of different ages. Pretreatment with ethacrynic acid was followed by an increase in the renal excretion of PAH in 33-, 55-, 105- and 240-day-old rats but not in newborn rats. In 55-day-old rats the increase in renal excretion of PAH after pretreatment with ethacrynic acid was not associated with any consistent change of the glomerular filtration rate. It is concluded from these results that the stimulation of transport processes in the kidney by ethacrynic acid and some other drugs is linked with their affinity to tissue proteins. 相似文献
86.
R. Brändén T. Nilsson S. Styring J. Ångström 《Biochemical and biophysical research communications》1980,92(4):1306-1312
Preparations of RuBP carboxylase are shown to carry out an oxygen dependent decarboxylation of L-3-phosphoglyceric acid. The product of this reaction is probably phosphoglycollate. L-3-phosphoglyceric acid, formed by RuBP carboxylase is therefore proposed to be the primary substrate for photorespiration. 相似文献
87.
On the origin of Z-band material and myofilaments in myoblasts from the human atrial wall 总被引:1,自引:0,他引:1
Dr. Thorvald Sætersdal Hogne Engedal Reidar Lie Reidar Myklebust 《Cell and tissue research》1980,207(1):21-29
Summary The origin of cardiac myofibrils in cells from the atrial wall in human embryos was studied. Z-band substance appears throughout the cytoplasm as irregular electron dense patches in a network of thin filaments. The thin and thick filaments are synthesized as separate units in the sarcoplasm and are later aggregated into myofibrils. Complexes of Z substance and thin filaments occur numerously at different stages of myofibrillar organisation. Thick filaments are formed in close proximity to free ribosomes and are later incorporated in an hexagonal pattern into the Z-band/thin filament complex.This work was supported by grants from The Norwegian Council on Cardiovascular Disease and from The Norwegian Research Council for Science and the Humanities 相似文献
88.
R S Dreizin V Strizová T I Ponomareva L Syr?cek E M Vikhnovich N M Borovkova G V Geine E V Klimanskaya M Br?cková L Kuncová V Berkovicová 《Journal of hygiene, epidemiology, microbiology, and immunology》1979,23(2):174-185
Virological, serological and immunofluorescence studies revealed circulation of rhinoviruses of the strains 1A, 1B, 2, 3, 7, 9, 10, 12, 13, 14, 16-23, 27, 29-33, 42, 48, 53, 56, 60 and 69 on the territory of Czechoslovakia and the Soviet Union. According to virological results, type 48 predominated and was followed in frequency of occurrence by types 27, 14 and 16 in the USSR and 30, 1A and 31 in the CSSR. RV infection in adults with ARD diseases was the aetiology in 28.5% of cases. Among the causative agents of acute rhinitis, rhinosinusitis and otitis, rhinovirus infection makes up a large proportion. Interrelation has been found between rhinovirus infection and chronic inflammation of the mucosa of the nose, the accessory sinuses and the ears. Prolonged course of rhinovirus infection and isolation of the virus in the late stages of disease (1-4 months after its onset) support the presumption that rhinoviruses promote chronicity of inflammation. RV was isolated from patients with chronic pneumonia from the lower respiratory passages (bronchial secretion). Rhinoviraemia was found in a child who died of ARD. 相似文献
89.
Summary A large family is reported in which mental retardation associated with the fragile site at Xq28 was found. Three normal males seemed to have transmitted the trait through their daughters to affected grandchildren.A total of 19 family members were investigated cytogenetically. Mentally retarded males showed macroorchidism and the fragile X. Three mentally retarded females were found, with the fragile X in a high percentage of cells; in contrast, the obligate carriers showed no or only few cells with the fragile X. 相似文献
90.
Calmodulin stimulated 45Ca2+ uptake into a plasma membrane enriched fraction from ox neurohypophysial nerve endings and into a microsome fraction. The 45Ca2+ uptake and the (Ca2+-Mg2+) ATPase activity in the plasma membrane fraction exhibited similar pCa and calmodulin sensitivities, suggesting that the enzyme activity is the biochemical expression of a high affinity Ca2+ pump. Calmodulin thus seems to play a role in regulation of the intracellular free Ca2+ concentration in the neurohypophysis. 相似文献