Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 7

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  envelope
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

The ultrastructure of the oncospheral envelopes of Fimbriaria czaplinskii Grytner-Ziecina, 1994 [Cestoda, Hymenolepididae]

100%
Chomicz L.
Acta Parasitologica
|
1996
|
tom 41
|
nr 4
The envelopes of oncospheres of a hymenolepidid tapeworm with an aquatic life cycle Fimbriaria czaplinskii, surrounding larvae inside the gravid part of the strobila, were examined under a transmission electron microscope. Details of the ultrastructure of the outer envelope and the inner envelope with its two derivatives: the embryophore and oncospheral membrane are described. The ultrastructural features of F. czaplinskii envelopes are compared and discussed with those described previously in the other hymenolepidids, and particularly with the related species Fimbriaria fasciolaris.
2

Morphological studies on envelopes of oncospheres of the hymenolepidid cestode, Fimbriaria fasciolaris [Pallas, 1781]

100%
Chomicz L., Grytner-Ziecina B., Walski M.
Acta Parasitologica
|
1995
|
tom 40
|
nr 1
The envelopes of oncospheres of Fimbriaria fasciolaris, found in the distal part of the strobila or free, were the subject of scanning electron microscope (SEM) and light microscope (LM) studies. The oncospheres inside the strobila were in close apposition to the uterine wall and showed morphological ties suggesting metabolic interactions. SEM studies allowed us to discern 3 stages of uterine development: early - with a continuous, tubular, and branched uterus; intermediate - with bulging parts of the uterus forming uterine capsules packed with oncospheres; late - with the uterus discontinuous, breaking down into uterine capsules, either individual or connected into chains of different lengths, containing 1 to 12 oncospheres. The uterine epithelium within uterine capsules was structurally heterogeneous, closely connected with the oncospheres, constituting a common uterine envelope. Infective eggs outside the strobila were deprived of the uterine envelope, and were joined together by separate external envelopes, easily visible in the LM. Live oncospheres observed over a 24 h period after liberation from the strobila exhibited alterations in taxonomically important features, such as dimensions and shape of the external envelope. The possible roles of different envelopes are discussed.
3
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Geometric modeling of reflected sound waves in the threecentred arch

84%
Kernytskyy I., Nikitenko O.
Acta Scientiarum Polonorum. Architectura
|
2018
|
tom 17
|
nr 1
Currently, reflecting systems are widely used in heating equipment, solar engineering structures and acoustic structures. Here, constructions based on classical curves do serve in reflectors. The reflection trajectories represent such curves as podera, orthotomic and caustic paths. Research goal to find an analytical description of the threecentred curve, its podera and orthotomics, and to build a reflecting geometric model of the existing this arch. Such curves’ analytical description has been carried out using analytical geometry on the plane. First, we derived podera and orthotomics formulas for a circle, and then for the threecentred arch properly. For the geometric modeling of reflected sound waves in the threecentred arch, we selected the existing arch, this one of the Yusupov Palace Trapeznaja Palata. The subject arch graphic representation has been build in the AutoCAD editor, including the structure of arch properly, its podera, orthotomics and caustic for its threecentred part. Results obtained actually affirmed the proficient acoustic phenomena knowledge appropriate to the ancient architects capable to apply correctly in practice their skills.
4

SIRE-1, a putative plant retrovirus is closely related to a legume Ty1-copia retrotransposon family

84%
Pearce S. R.
Cellular and Molecular Biology Letters
|
2007
|
tom 12
|
nr 1
SIRE-1 is a potential soybean retrovirus which has a gene order similar to Ty1-copia retrotransposons but also contains an envelope-like open reading frame (ORF), which is characteristic of retroviruses. PCR and Southern analysis reveals that SIRE-1 is closely related to a legume-wide family of envelope-lacking Ty1-copia group retrotransposons which suggests that SIRE-1 was formed by the recent acquisition of an envelope gene by a Ty1-copia retrotransposon.
5

Ultrastructure of oncospheral envelopes and their differentiation in the cestode, Dicranotaenia coronula [Dujardin, 1845] [Cyclophyllidea, Hymenolepididae]

67%
Chomicz L., Swiderski Z., Grytner-Ziecina B.
Acta Parasitologica
|
1995
|
tom 40
|
nr 1
Studies of the ultrastructure of oncospheral envelopes and their differentiation in the hymenolepidid cestode Dicranotaenia coronula in utero revealed four main envelopes: (1) capsule, (2) outer envelope, (3) inner envelope with a thin, electron-dense embryophore, and (4) oncospheral membrane. An additional hemispherical calotte, the hook region membrane covers one pole of the oncosphere and is attached to its surface. Both the outer and inner envelope represent syncytial layers which contain large, flattened nuclei of blastomeres which participated in their formation: nuclei of macromeres in the outer, and nuclei of mesomeres in the inner envelope. The granular cytoplasm of the both envelopes contains a large amount of free ribosomes, numerous mitochondria and several lipid droplets. The primary inner envelope of the early embryo forms in the later stage of embryogenesis its two derivatives: the embryophore and the oncospheral membrane. The hook region membrane oryginates from a syncytial binucleate complex by delamination of its cytoplasmic plate. Both the ultrastructural features of oncospheral envelopes and mode of their differentiation are compared with those described previously in the other hymenolepidids with aquatic and terrestrial life cycles. The ultrastructure of the oncospheral envelopes in D. coronula is discussed in relation to its life cycle and to environmental conditions in which the infective eggs remain for a certain period of time, until eaten by benthal ostracods, the intermediate hosts of D. coronula.
6

Ultrastructure of the infective eggs of the hymenolepidid cestode, Ditestolepis tripartita [Zarnowski, 1955], a parasite of shrews

67%
Swiderski Z., Tkach V.
Acta Parasitologica
|
1997
|
tom 42
|
nr 1
The ultrastructure of infective eggs of the hymenolepidid cestode, Ditestolepis tripartita, a parasite of shrews, was examined with emphasis on cellular organisation of mature oncospheres. Each hexacanth larva is surrounded by three main egg envelopes: thin layer of amorphous outer envelope, relatively thick layer of inner envelope with an embryophore and a delicate oncospheral membrane. The outer and inner envelopes of infective eggs of D. tripartita are usually amorphous; the embryophore is relatively thin and moderately electron-dense. Five major types of oncospheral cells have been distinguished. These consist of: (1) about ten germinative cells; (2) about 30 somatic cells (= myocytons of somatic and hook muscles); (3) a bi-nucleate medullary centre (= tegumental perikaryon); (4) a bi-nucleate, U-shaped penetration gland and (5) two cells of neurosecretory type with characteristic dense-cored vesicles. The hook-muscle system with complex interconnections between different muscle fibers provides a structural basis for coordinated hook action.
7

Comparative ultrastructure and elemental composition of envelopes of Trachelomonas and Strombomonas [Euglenophyta]

67%
Conforti V., Walne P. L., Dunlap J. R.
Acta Protozoologica
|
1994
|
tom 33
|
nr 2
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.