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101.
Prof. Dr. med. Heiko Braak 《Cell and tissue research》1979,204(3):431-440
Summary Cortical lamination and parcellation of the retrosplenial region in the human brain is evaluated with the aid of frontal serial sections stained for nerve cells (15 m), myelin sheaths (100 m), and lipofuscin granules (800 m).For the most part, the retrosplenial region is buried in the depth of the sulcus corporis callosi covering the posterior parts of the cingulate gyrus. It lies between the supracallosal derivatives of the allocortex (fascia dentata, cornu ammonis, subiculum) and the mature parietal isocortex.The region can be subdivided into five areas. The transitory periallocortical Area ectosplenialis is followed by a richly differentiated proisocortical core displaying extremely externopyramidal, externoteniate, and astriate to unitostriate characteristics. The parvocellular core is averagely poor in pigment (Typus clarus) and rich in myelinated fibres (Typus dives). Minor structural differences allow for its subdivision into a lateral, an intermediate, and a medial retrosplenial field. The accompanying Area parasplenialis is adjacent to the equoteniate parietal isocortex. It is only weakly externopyramidal, externoteniate, and propebistriate. The already homotypical field shows an average pigmentation and myelin content. These structural features permit its classification as a belt area of the retrosplenial core.Supported by grants from the Deutsche Forschungsgemeinschaft 相似文献
102.
103.
Dr. Federico Carbone Prof. Dr. Ruggero Matteucci Dr. Brian R. Rosen Prof. Dr. Antonio Russo 《Facies》1994,30(1):1-13
Summary From a study of two areas, Jesira and the Bajuni Archipelago, about 400 km apart, a general pattern can be established for
the Recent facies, together with the morphological and taxonomic features of the corals. Present day coral development is
characterized by true fringing reefs in the Bajuni Archipelago and by scattered patches and knolls in the Jesira area. The
coral fauna, consisting of 27 genera and 63 species so far (including all uncertainties, but not sight records), is rather
poor, though coral communities are locally well developed. These figures probably reflect incomplete study and sampling. Although
comparison with other areas may therefore be premature, a preliminary biogeographical analysis suggests that this fauna is
more closely related to that of the Red Sea than to East Africa and the Seychelles. This differs from other published biogeographical
work on Indian Ocean coral faunas, but further study of the corals in this and neighbouring areas of the Indian Ocean is needed
in order to resolve this apparent anomaly. 相似文献
104.
Summary Mitochondrial abnormalities are reported in four cases of phaeochromocytoma. These abnormalities include swelling and scant cristae, intramitochondrial dense bodies, septate-like junctions, intercristal fusion plus spheroidal bodies, and intramitochondrial rodlets. These structural mitochondrial changes are associated with reduction in activity of the mitochondrial enzymes, monoamine oxidase and succinic dehydrogenase.Supported by a grant-in-aid from the National Health and Medical Research Council 相似文献
105.
Prof. Dr. Rainer H. Lange A. R. Soames Raymond Coleman 《Cell and tissue research》1974,153(2):167-173
Summary Crystalline inclusions in parathyroid gland cell nuclei of Rana temporaria were studied by electron microscopy using a specimen tilting stage. Images were analysed by optical diffraction. Results were compared with X-ray and electron microscopic data of trigonal bovine liver catalase to which a striking resemblance of the inclusions was found.We are grateful to Professor R. Mosebach (Giessen) for discussions, to the Deutsche Forschungsgemeinschaft for a grant (La 229/4) and instruments and to Messrs. Spindler & Hoyer, Göttingen and Messrs. Rank Precision Instruments, Nürnberg for putting apparatus at our disposal and performing diffraction photographs. 相似文献
106.
Immunocytochemistry and ultrastructure of the neuropil located ventral to the rat supraoptic nucleus
C. R. Yulis B. Peruzzo Prof. E. M. Rodríguez M.D. Ph.D. 《Cell and tissue research》1984,236(1):171-180
Summary The neuropil located ventral to the SON was investigated by the use of immunoperoxidase staining for neurophysins, oxytocin and vasopressin, and electron miroscopy. The study was performed in six groups of rats: 1) control; 2) infusion of isotonic saline into the CSF; 3) infusion of hypertonic saline into the CSF; 4) drinking hypertonic saline for 4 days; 5) same as group 4 but injection of colchicine into the CSF on second day of dehydration; 6) salt loading for 3 months. In the control rats the ventral neuropil contained a few immunoreactive processes, the general morphology of which was completely different from that of the neurosecretory axons emerging from the SON at its dorsal aspect. In rats of groups 3 to 6 the ventral processes (VP) became loaded with neurosecretory granules, whereas the perikarya and axons were depleted. Based on their general morphology and reactivity pattern it is suggested that the VP are dendrites. Most of these dendrites were embedded in a glial cushion formed by the processes of a particular type of marginal glia. Some of these dendrites enveloped an arteriole penetrating the optic tract. All VP were rich in synaptic contacts. The possibility that the VP of neurosecretory cells may be functionally related to the subarachnoid CSF and the arteriolar blood flow is discussed.Supported by Grant RS-82-18 from Direccíon de Investigaciones, Universidad Austral de Chile 相似文献
107.
Prof. Dr. Heribert Warzecha 《当今生物学》2011,41(3):198-205
Hightech from Natures Pharmacy Plants produce a plethora of valuable natural products, many of which are used as pharmaceuticals. Today, a large fraction of the novel pharmaceuticals entering the market are biomolecules of proteinaceous nature (antibodies, hormones, cytokines, vaccines) and they are produced in transgenic organisms like bacteria, yeast, or mammalian cell cultures. Plants are also capable to serve as a production host for novel therapeutics like monoclonal antibodies, hormones like insulin, or subunit vaccines. Transgenic plants and plant cell cultures are already modified to produce protein biopharmaceuticals and vaccines on a large scale basis and in some aspects they have clear advantages over conventional production hosts (e.g. cost of goods, speed of production, or posttranslational modification of therapeutic proteins). Therefore, plant biotechnology could create entirely novel medicinal plants with applications not known before. 相似文献
108.
Prof. Dr. med. Helmut Leonhardt 《Cell and tissue research》1968,88(3):297-317
Zusammenfassung Die Wand des III. Ventrikels (Regio hypothalamica) vom erwachsenen Kaninchen wurde elektronenmikroskopisch untersucht. — Unterschiedliche keulenförmige portsätze, deren Perikaryen in nahen und entfernten Regionen liegen, dringen in den Ventrikel ein. Sie heben eine Ependymzelle ab und bilden eine bukettförmige Struktur. Einige Fortsätze enthalten eine spärliche feingranulierte Masse, andere Bläschen (600–1500 Å) oder Bläschen mit dichtem Kern (450–1200 Å). Inmitten des Buketts kann eine Nervenzelle liegen, die einen dicken Fortsatz gegen das Hypendym schickt. Unterhalb des Buketts findet man eine andere Nervenzelle, die Fortsätze ins Bukett sendet. Zahlreiche in das Bukett eintretende Fortsätze stammen aus entfernteren Kerngebieten. Die funktionelle Bedeutung der Strukturen (Neurosekretion ? Resorption ? Rezeptor ?) wird diskutiert.
Die Untersuchung wurde mit dankenswerter Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt. 相似文献
Bouquet-like ependymal structures in the hypothalamic region of the 3rd Ventricle (rabbit)The question of neurosecretion or receptor function
Summary The wall of the III. ventricle (Regio hypothalamica) of the adult rabbit has been investigated electron microscopically. —Various bulblike processes of nerve cells, having their perikarya in close or distant regions, penetrate into the ventricle. They lift an ependymal cell and form a bouquet-like structure. Some of the processes contain a sparse granulated material and others include vesicles (600–1500 Å) or dense-cored vesicles (450–1200 Å). In the middle of the bouquet a perikaryon may be seen extending a thick process towards the hypendyma. Below the bouquet another perikaryon may be found extending several processes into the bouquet. The functional significance of these structures (neurosecretion ? resorption? receptor?) is discussed.
Die Untersuchung wurde mit dankenswerter Unterstützung durch die Deutsche Forschungsgemeinschaft durchgeführt. 相似文献
109.
Prof. Dr. Eng. S. Furusaki Dr. Agr. T. Nozawa S. Nomura 《Bioprocess and biosystems engineering》1990,5(2):73-78
A membrane enzyme reactor with simultaneous separation was investigated. Enzymes, urease and aspartase, were immobilized by a porous polytetrafluoroethylene membrane. Electrical field was applied in the medium while the reaction was carried out. Products with electrical charge could be separated through the membrane from the reaction medium as they were formed. Reaction behavior was analyzed by a simple model considering both pore-migration and reaction in the skelton of the membrane. According to the analysis the inherent reaction rate of the immobilized enzymes decreases significantly. This is probably caused by the structural variation of enzymes. For the case of urease, the change of pH inside the membrane may also cause the decrease of the reaction rate. The model analysis showed that the enzyme content in the membrane and the residence time of the substrate in the membrane governed overall extent of reaction.List of Symbols
e g (dm3)–1
enzyme concentration in the membrane
-
L cm
membrane thickness
-
K
m
mM
Michaelis constant
-
Rate mmol · min–1 · g–1
rate of product formation per unit weight of enzyme
-
S mM
substrate concentration
-
S
in mM
inlet substrate concentration
-
S
out mM
outlet substrate concentration
-
u cm · min–1
migration rate
-
V V
voltage between the electrodes
-
V
m mmol · min–1 · g–1
maximum reaction rate
-
X
conversion
-
z cm
distance from the surface inside the membrane
-
void fraction of the porous membrane
-
tortuosity of the membrane
-
min
space time 相似文献
110.