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1.
Summary An electronmicroscopic study on the development of the acrosome system of the spermatozoon in the Norwegian lemming (Lemmus lemmus) has been performed. The proacrosomal granules were found to be few and to consist of a dense center and a less dense periphery, and the acrosomal vesicle to contain stainable material of the same structure but of lower density than that of the acrosomal granule. Like in the guinea pig, two zones of different density exist throughout acrosome development and are visible also in mature spermatozoa. A large osmiophilic formation consisting of saccular, tubular, and lamellar structures, was found between the apex of the condensed nucleus and the acrosome and was identified as perforatorium.We are greatly thankful to Dr. Antti Telkkä, and Mr. Mauri Nyholm, M. Sc. for expert advise in electronmicroscopy and Mr. P. Lehtimäki for photographic help. For the supply of the lemmings we are indebted to Prof. K. Lagerspetz, and Mr. O. Hissa, M. Sc. This work is related to a series of studies on the biology of the Norwegian lemming (for previous works see Asp et al.). 相似文献
2.
Frank Mayer 《Planta》1966,71(1):15-19
Summary In the light microscope the nuclei of the leaf cells of Selaginella martensii show ring-shaped inclusions. These rings are Feulgen positive and most probably contain DNA. An electron microscopic examination of these ring-shaped inclusions shows that they are composed of closely packed tubular elements which have a constant diameter and unknown length. These bundles are often surrounded by a number of larger tubular elements which may be built up of tubular subunits.
Direktor: Prof. Dr. A. Frey-Wyssling
(Prof. Dr. W. Haupt) 相似文献
Elektronenmikroskopische Untersuchung Tubulärer Strukturen in den Kernen der Blattzellen von Selaginella Martensii
Zusammenfassung Die Kerne der Blattzellen von Selaginella martensii zeigen im Lichtmikroskop ringförmige Einschlüsse. Diese Ringe sind Feulgen-positiv, enthalten also wahrscheinlich DNS. Sie bestehen aus einem dichtgepackten Bündel tubulärer Elemente konstanten Durchmessers, jedoch nicht genau bestimmbarer Länge. Die Ringe sind häufig von einer wechselnden Zahl größerer tubulärer Stränge umgeben, die aus röhrchenförmigen Untereinheiten bestehen können.
Direktor: Prof. Dr. A. Frey-Wyssling
(Prof. Dr. W. Haupt) 相似文献
3.
Gezginci-Oktayoglu S Tunali S Yanardag R Bolkent S 《Molecular and cellular biochemistry》2008,309(1-2):9-20
Background The aim of this investigation was to demonstrate that benzyloxicarbonyl-l-phenylalanyl-alanine-fluoromethylketone (Z-FA.FMK), which is a pharmacological inhibitor of cathepsin B, has protective role
on the kidney injury that occurs together with liver injury. Methods BALB/c male mice used in this study were divided into four groups. The first group was given physiologic saline only, the
second group was administered Z-FA.FMK alone, the third group received d-galactosamine and tumor necrosis factor-alpha (d-GalN/TNF-α), and the fourth group was given both d-GalN/TNF-α and Z-FA.FMK. One hour after administration of 8 mg/kg Z-FA.FMK by intravenous injection, d-GalN (700 mg/kg) and TNF-α (15 μg/kg) were given by intraperitoneal injection. Results In the group given d-GalN/TNF-α, the following results were found: severe degenerative morphological changes in the kidney tissue, a significant
increase in the number of activated caspase-3-positive tubular epithelial cell, an insignificant increase in the number of
proliferating cell nuclear antigen (PCNA)-positive tubular epithelial cell, a decrease in the kidney glutathione (GSH) levels,
catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, an increase in the kidney lipid peroxidation
(LPO) levels, lactate dehydrogenase (LDH) activity, serum aspartate aminotransferase (AST), and alanine aminotransferase (ALT)
activities, uric acid and urea levels. In contrast, in the group given d-GalN/TNF-α and Z-FA.FMK, a significant decrease in the d-GalN/TNF-α-induced degenerative changes, a decrease in the number of activated caspase-3-positive tubular epithelial cell,
a insignificant decrease in the number of PCNA-positive tubular epithelial cell, an increase in the kidney GSH levels, CAT,
SOD and GPx activities, a decrease in the kidney LPO levels, LDH activity, serum AST and ALT activities, uric acid and urea
levels were determined. Conclusion These results suggest that pretreatment with Z-FA.FMK markedly lessens the degree of impairment seen in d-GalN/TNF-α-induced kidney injury, which occurred together with liver injury in mice. 相似文献
4.
Yoshiko Kira Yutaka Okazaki Tsuyoshi Sawada Makoto Takafuji Hirotaka Ihara 《Amino acids》2010,39(2):587-597
Self-assembling amphiphiles with unique chiroptical properties were derived from l-glutamic acid through ω-aminoalkylation and double long-chain alkylation. These amphiphiles can disperse in various solvents
ranging from water to n-hexane. TEM and SEM observations indicate that the improvement in dispersity is induced by the formation of tubular and/or
fibrillar aggregates with nanosized diameters, which makes these amphiphiles similar to aqueous lipid membrane systems. Spectroscopic
observations, such as UV–visible and CD spectroscopies indicate that the aggregates are constructed on the basis of S- and R-chirally ordered structures through interamide interactions in water and organic media, respectively, and that these chiroptical
properties can be controlled thermotropically and lyotropically. It is also reported that the chiral assemblies provide specific
binding sites for achiral molecules and then induce chirality for the bonded molecules. Further, the applicability of the
amphiphiles to template polymerization is discussed. 相似文献
5.
Samir M. El Shoura 《Experimental & applied acarology》1988,4(2):95-108
The fine structure of the reproductive system of the unfed femaleOrnithodoros (Pavlovskyella) erraticus is described. The vagina consisting of vestibular (vv) and cervical (cv) regions is formed of a single epithelial layer lined with cuticle and surrounded by muscle layers. Epithelial cells ofvv show no signs of activity, while those ofcv have structural features of transporting epithelia. A pair of tubular accessory glands opening at the junction of the two vaginal regions consist of a layer of microvillate columnar cells containing rough endoplasmic reticulum; this is possibly involved in the formation of colloidal material which presumably coats the egg surface during its passage through the vagina. The bilobed uterus opening into the cervical vagina secretes material that is possibly responsible for the release of sperm from the endospermatophore. The paired oviducts joining the uterine lobes anteriorly have distinctive distal (do) and proximal (po) parts as well as ampullae (amp) at their junction.do cells contain many lysosome-like structures which probably play a role in breaking down some sperms ascending to the ovary. Cells ofamp are packed with rickettsia-likeWolbachia, while those ofpo contain a few granules. Gene's organ, present in female ticks only, consists of a stalk and two horns of epithelium lined internally by a cuticular layer. Bundles of microtubules are detected in the horn cell cytoplasm. This organ functions to waterproof the eggs with a waxy layer just before they are deposited. 相似文献
6.
Summary. Hydrogensquarates of dipeptide l-threonyl-l-serine (H-Thr-Ser-OH) and l-serine (HSq × Ser) have been synthesized, isolated and spectroscopic characterized by solid-state linear-polarized IR-spectroscopy, 1H- and 13C-NMR, ESI-MS and HPLC with tandem masspectrometry (MS-MS) methods. The structures of the salts and neutral dipeptide have
been predicted theoretically by ab initio calculations. In the case of H-Thr-Ser-OH the theoretical data are supported by IR-LD ones. The hydrogensquarates consist in positive charged dipeptide or amino acid
moiety and negative hydrogensquarate anion (HSq) stabilizing by strong intermolecular hydrogen bonds. The data about the l-serine hydrogensquarate are compared with known crystallographic data thus indicating a good correlation between the theoretical
predicted structures and experimentally obtained by single crystal X-ray diffraction. 相似文献
7.
Relationship of nuclear membranes with filaments and microtubules 总被引:10,自引:0,他引:10
Werner W. Franke 《Protoplasma》1971,73(2):263-292
Summary In certain HeLa cells characteristic aggregates of cytoplasmic filaments, microfilaments and microtubules were found which preferentially encompass the nucleus. These structures are intimately associated with the membranes of the nuclear envelope and the endoplasmic reticulum as well as with ribosomes. Starting from this observation, a review is presented which demonstrates the nuclear membranes generally as being a type of membrane with a close relationship to proteinaceous structures of the actin-like type such as microtubules and (micro)filaments. As an explanation for the phenomena observed, it is hypothesized that the formation of such tubules and filaments is nucleated at cytomembraneous surfaces and/or that membrane (and possibly also ribosomal) material can be transformed to such tubular or filamentous structures. The concept of cocrystallization between membranes and the diverse tubular and filamentous categories and of a transformation of membrane protein moieties into such structures is thought to provide a basis for explaining many structural phenomena involving membranes and structures of actin-like proteins.The author gratefully acknowledges the careful technical assistance of MissSigrid Krien and MissMarianne Winter and valuable discussions with his colleagues, Drs. H.Falk, H.Kleinig, U.Scheer, as well as with Drs. M.Moses (Duke University), D. J.Morré (Purdue University), and K.Wolff (University of Vienna). The work was supported by the Deutsche Forschungsgesellschaft. 相似文献
8.
A new species,Taraxacum siphonanthum X.D.Sun, Ge Xuejun, Kirschner & Štěpánek is described from Nei Mongol, NE China. The species is intermediate between sectionsMongolica andBorealia, although in most characters it is closer to the former. It is an apomictic species with tubular florets; these and other similar characters inTaraxacum are discussed. 相似文献
9.
Gérard Strecker Jean-Michel Wieruszeski Claude Martel Jean Montreuil 《Glycoconjugate journal》1987,4(4):329-337
Alkaline borohydride reductive cleavage of hen ovomucin resulted in the release of a series of neutral and acidic oligosaccharide-alditols.1H-NMR spectroscopy in combination with fast ion bombardment-mass spectrometry in negative ion mode were used for investigation of the structures of three oligosaccharide-alditols. The following structures were established:
Abbreviations NeuAc
N-acetyl-d-neuraminic acid
- Gal
d-galactose
- GlcNAc
N-acetyl-d-glucosamine
- Gal-NAc-ol
N-acetyl-d-galactosaminitol
- NMR
nuclear magnetic resonance
- FAB-MS
fast atom bombardmentmass spectrometry 相似文献
10.
Lieselotte Rentschler 《Molecular & general genetics : MGG》1967,100(1):96-108
Summary The primary structures of the coat proteins of three strains of TMV were established (Anderer et al., 1965; Wittmann-Liebold u. Wittmann, 1963; Wittmann 1965; Rentschler part I of this paper). They differ from one another in 29, 35 and 40 positions. Since the primary structure of a protein determines its secondary and tertiary structure, the geometry of the subunits and the cause of aggregation were investigated to see how they were influenced by the primary structures.The aggregation of the native proteins as a function of pH and ionic strength was investigated by determining sedimentation coefficients. All three proteins showed a similar cause of aggregation.The geometry of the subunits was compared in experiments with mixed aggregates (Sarkar, 1960). The result was that the subunits of U2 were able to form mixed aggregates with dahlemense and vulgare subunits. From this one can conclude that the geometrical properties of the three subunits are very similar.The A-Protein, the larger aggregates, and protein denatured in 8 M urea differed in their charge distributions. The differences seem to be located in regions of the polypeptide chain where they cause no disturbances and where they do not affect the aggregation properties.How to visualize the striking similarity of aggregation behaviour in spite of the great differences in primary structures is discussed on the basis of the conception of Tanford (1962) and Epstein (1964).
2. Teil einer Dissertation der Mathematisch-naturwissenschaftlichen Fakultät der Universität Tübingen. 相似文献
2. Teil einer Dissertation der Mathematisch-naturwissenschaftlichen Fakultät der Universität Tübingen. 相似文献
11.
Unprotected l-phenylalanine was derivatized by an innovative enzymatic method by means of laccases from Pycnoporus cinnabarinus and Myceliophthora thermophila. During the incubation of l-phenylalanine with para-hydroquinones using laccase as biocatalyst, one or two main products were formed. Dependent on the substitution grade of
the hydroquinones mono- and diaminated products were detected. Differences of the used laccases are discussed. The described
reactions are of interest for the derivatization of amino acids and a synthesis of pharmacological-active amino acid structures
in the field of white biotechnology. 相似文献
12.
Summary Purified proteins from sieve tubes ofCucurbita maxima were precipitated with vinblastine and the precipitates were analyzed with the electron microscope. Filaments (35–40 Å in diameter) and tubular structures (160 Å in width) were observed in negatively stained preparations. The predominant structures of the negatively stained and of the thin sectioned material, however, were membrane-like sheets (100–120 Å in width) which showed the typical unit membrane aspect.Dedicated to Professor Dr. W.Schumacher on his 70th birthday.The investigations were supported by the Deutsche Forschungsgemeinschaft. 相似文献
13.
Marc Horisberger 《Archives of microbiology》1977,112(3):297-302
The peptidoglycans of Moraxella glucidolytica and Moraxella lwoffi grown on aliphatic hydrocarbons were isolated. They contained muramic acid. glucosamine, alanine, d-glutamic acid and meso-diaminopimelic acid in a molar ratio of about 0.5:0.5:1.6:1.0:1.0 (M. glucidolytica) and 0.8:0.7:1.3:1.0:1.0 (M. lwoffi).The peptidoglycans were lysozyme-resistant. However, when treated with formamide, they could be partially degraded by lysozyme. The fragments were purified and their structure determined. In both strains, the peptide subunits consisted mainly of tripeptides (l-Ala-d-Glu-meso-DAP) and tetrapeptides (l-Ala-d-Glu-meso-DAP-d-Ala), most of them being directly cross-linked. It is concluded that in both strains the primary structures of the peptidoglycans are closely related. 相似文献
14.
Gerhard Pils 《Plant Systematics and Evolution》1980,136(1-2):73-124
The biosystematics of theFestuca violacea group (F. rubra subsp.violacea sensuHackel) in the Eastern Alps is studied.F. picturata
Pils (=F. picta
Kit. exSchultes nonJ. F. Gmelin) is confirmed as diploid, whereas the chromosome numbers forF. nitida (diploid),F. puccinellii (hexaploid), andF. norica (diploid, tetraploid and hexaploid) are reported for the first time. Details of morphology, leaf anatomy, and epidermal structures now allow a better separation of these species; new maps illustrate their distribution. Karyological, chorological, morphological, and anatomical data form the basis for a discussion of the phylogeny of theF. violacea group and its position withinF. rubra s. latiss. 相似文献
15.
Bernard Priem Julien Solokwan Jean-Michel Wieruszeski Gérard Strecker Hassan Nazih Henri Morvan 《Glycoconjugate journal》1990,7(2):121-132
The oligosaccharides Man5GlcNAc and Man3(Xyl)GlcNAc(Fuc)GlcNAc presumed to originate fromN-glycosyl proteins have been purified from an extracellular medium (concentration: 2–5 mg/l of 14 day cultures) of white campion (Silene alba) suspension culture. Their primary structures have been determined by1H-400-MHz NMR spectroscopy and FAB-MS spectrometry. They are probably the result of an autophagic process including protein catabolism due to sucrose starvation. Additional identification of digalactosylglycerol (galactolipid breakdown) argues for this hypothesis.Abbreviations Fuc
l-fucose
- Man
d-mannose
- Xyl
d-xylose
- GlcNAc
N-acetyl-d-glucosamine
- Gal
d-galactose
- Glc
d-glucose
- FAB-MS
fast atom bombardment mass spectrometry
- NMR
nuclear magnetic resonance 相似文献
16.
Christian B. Skovsted 《Pal?ontologische Zeitschrift》2003,77(2):429-443
Mobergellans are disc-shaped problematic fossils of phosphatic composition bearing prominent muscle attachment structures
on the presumed internal surface. They are found exclusively in sediments of Early Cambrian age, mainly from Laurentia, Baltica
and Siberia. Type material ofDiscinella brastadi Poulsen, 1932 from North-East Greenland is re-studied and synonomised withDiscinella micans (Billings, 1871). Specimens from Siberia described asD. brastadi are re-assigned toMobergella hexactina n. sp., and specimens from Siberia described asMobergella radiolata
Bengtson, 1968 are re-assigned toM. sibirica n. sp.Aktugaia triangula
Mis-Sarzhevsky, 1976 from Kazakhstan is redescribed, and its relationship to other mobergellans is discussed.
相似文献
17.
Thetrans-4-hydroxy-(l)-proline productivity and morphological characteristics of strains isolated from two different conidium-producing structures inClonostachys cylindrospora were compared.trans-4-Hydroxy-(l)-proline was found to be produced only by strains originating from conidia on penicillate conidiophores, not by strains originating from conidia on verticillate conidiophores. Strains from each conidium-producing structure were also segregated by morphological properties; i.e., the amount of aerial hypha produced on modified Weitzman's agar, production of water-soluble yellow pigment in potato-dextrose agar, the primarily formed conidium-producing structures, and sclerotium formation. These phenomena indicate that morphological characteristics and metabolite productivity are correlated and destined at the stage of conidial production inC. cylindrospora. 相似文献
18.
Summary The spermatozoa of Peregrinus maidis Ashm. are thread-like, approximately 650 long and 1 wide including the head (approximately 28 ).The main part of the spermatozoa consists of two mitochondria derivatives, a central body between them, the axial filament complex, and a newly found element consisting of two wing-shaped bodies. Each mitochondrion derivative shows a peripheral and an inner part. The peripheral part is formed by cristae arranged perpendicularly to the long axis of the spermatozoon. The cristae are approximately 70 Å wide. The dense layers between them measure approximately 280 Å. The inner part of the mitochondrion derivative shows a crystalline array, formed by sub-units of approximately 100 Å diameter. The wing-shaped bodies consist of tubular elements.The head has an elongated nucleus with an electron transparent space inside. At the anterior end of the nucleus lies a tapered acrosome. This appears fibrous and parts of the acrosome fibers seem to run along the nucleus.
Acknowledgements. The authors wish to thank Dr. G. H. Bergold for suggestions and support, Drs. J. André, D. W. Fawcett, P. Maillet and G. F. Meyer for very helpful discussion. They are also grateful to Mr. O. Suárez for assistance in the preparation of the organs of P. maidis and to Mrs. M. de Pingarrón for technical assistance. 相似文献
19.
Summary Cylindrical structures with outside diameters of 390 to 410 Å have been observed in the chloroplasts of mature vegetative cells of the filamentous, green alga Sirogonium melanosporum. These cylindrical structures are either parallel to one another or randomly oriented in the stroma matrix of the chloroplast. Some of the outer cylindrical structures of the complex appear to be continuous with thylakoid membranes, suggesting a relationship between these two structures.This work was supported by an Institutional Grant from the American Cancer Society to the University of Arizona and by grant GB2440 from the National Science Foundation to R. W. Hoshaw. The authors thank Dr. Wayneferris for the use of the electron microscope supported by NSF grant GB3330. 相似文献
20.
Zusammenfassung Das schlauchförmige, stark vaskularisierte Pinealorgan der Elritze (Phoxinus laevis L.) enthält zahlreiche Sinneszellen vom Typ der zilientragenden Photorezeptoren. Das sehr regelmäßig gebaute Außenglied dieser Sinneszellen besteht gewöhnlich aus 30–40 etwa 200 Å starken Plättchen, die durch multiple Invaginationen des Plasmalemms entstehen. Gelegentlich beobachtet man aber auch längere, bis zu 70 Plättchen tragende Sinnesfortsätze. Dieser Befund und weitere neurohistologische Ergebnisse sind eine morphologische Erklärung für die Lichtempfindlichkeit des Zwischenhirns augenloser Elritzen (von Frisch, 1911; E. Scharrer, 1928). Dem Vergleich dient das Pinealorgan der Regenbogenforelle, dessen Lichtempfindlichkeit vom Arbeitskreis Dodt in direkten Mikroelektrodenableitungen gesichert wurde.
Frau Prof. Dr. Berta Scharrer zum 60. Geburtstag in Verehrung gewidmet. Zugleich in dankbarer Erinnerung an Ernst Scharrer.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
Summary The tubular, highly vascularized pineal organ of the European minnow (Phoxinus laevis L.) contains a large number of sensory cells, which strongly resemble photoreceptors of the ciliary type. The outer segment of these cells consists generally of 30–40 discs.These elements, which are approximately 200 Å thick, are formed by multiple infoldings of the cell membrane. Certain longer outer segments contain at about 70 discs. These results and other neurohistological findings form an anatomical basis for the interpretation of the light-sensitivity of the diencephalon in blinded minnows (Von Frisch, 1911; E. Scharrer, 1928). The pineal receptors of Phoxinus should be compared with the ultrastructure of the pineal organ of the trout; in Salmo irideus light sensitive units of the pineal organ were recorded by means of microelectrodes (Dodt et al., 1963–1966).
Frau Prof. Dr. Berta Scharrer zum 60. Geburtstag in Verehrung gewidmet. Zugleich in dankbarer Erinnerung an Ernst Scharrer.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献