共查询到20条相似文献,搜索用时 15 毫秒
1.
F G Uglov V N Zubtsovski? O P Bol'shakov F A Mursalova A N Tarasov 《Arkhiv anatomii, gistologii i émbriologii》1984,87(9):33-41
Chosen at random 38 diastolic preparations of human hearts from persons having not any cardiac pathology, as demonstrate the postmortem examination, have been investigated. The left ventricle casts have been made during the first 24 hours after death according to a strictly fixed technique by means of filling the cardiac chambers with polymere mass--protacryl--under a physiological pressure of the diastolic filling. The trabecules are arranged as a spiral from the apex of the ventricle up to the atrioventricular fibrous ring, with approaching the apex the spiral step increases and the trabecules straighten. The left ventricle cast is devided into some planes, the envelopes and the trabecularity lines are measured. Average values of the shift in the trabecularity lines I, II, III and in the cross sections B, C, D, E are defined in relation to the plane A and in every case in relation to the previous plane Cn-1. The data obtained are presented in tables and diagrams. The greatest shift demonstrate the trabecularity lines I running predominantly along the posterior wall of the left ventricle in the planes B and which are situated nearer to the atrioventricular ring projection. Owing to the presence of the spiral-shaped course of the trabecules, it is possible to suppose that it influences the blood stream twisting clockwise in the left ventricle during the diastole phase. This indicates the necessity to work out some new constructions of artificial cardiac valves, securing the twisted blood stream. The condition mentioned should be taken into consideration while making prostheses of the cardiac valves. 相似文献
2.
Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices 相似文献
3.
K. Hausmann 《Protoplasma》1979,100(2):199-213
Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles. 相似文献
4.
S M Popkova E L Kichigina L I Dosiagaeva 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1983,(4):95-97
The results of the study of the immunological structure of the population at the western section of the Baikal-Amur Railroad in respect to influenza virus at different seasons of the year and with different intensity of the epidemic process are presented. The dynamics of the total level and properties of immunoglobulins of three classes (IgM, IgG and IgA) has been followed. The potential human capacity for immune response to infections under the conditions of the construction of the Baikal-Amur Railroad has been shown to remain unchanged. 相似文献
5.
The expression of allogenic inhibition was studied when transplanting 10(5) cells of bone marrow of C57BL mice to the lethally irradiated recipients (CBA X C57BL) F1 of different age (2 to 11 months). In the control experiments the bone marrow cells at the same dose were introduced to the lethally irradiated syngenic (C57BL) mice. The most pronounced inhibition of the parental stem cells proliferation was registered in 2 months old recipients F1 (4.7 times), it was somewhat weakened in 3 months old and animal in 4--11 months old recipients (1.1 to 1.8 times). The thymectomy of adult recipients F1 did not eliminate the expression of allogenic inhibition. 相似文献
6.
Daniel Stephan Stephanie Panzer Michael Göttlinger Peter Augat 《Computer methods in biomechanics and biomedical engineering》2014,17(15):1635-1641
Patients with calcaneus fractures experience considerable interferences with daily living activities. The quality of anatomical reconstruction is important because of its influence on functional outcome. The aim of this study was to develop an automatic algorithm based on computer tomographic (CT) images to quantify the integrity of calcaneal joint surfaces. Validation of this algorithm was done by assessing intra-individual variations of characteristic joint parameters. Bilateral hind foot CT data of 12 subjects were manually segmented, and 3D models from the calcaneus, talus and cuboid were generated. These models were implemented in a custom-made software to analyse the area, 3D orientations and bone distance of the joint surfaces of the calcaneus. Three joints were detected, and the calculated parameters were compared between right and left hind foot by the evaluation of the directional asymmetry (%DA). The results were statistically analysed with a paired t-test. The median of area (5–7 %DA) of the joint surfaces and the distance between two articulating surfaces (8–9 %DA) showed the greatest intra-individual differences. Median differences in 3D orientation were comparatively low (1–2 %DA). None of these differences was statistically significant. Inter-individual variations among subjects were several magnitudes larger than intra-individual differences. The presented computational tool provides 3D joint-specific parameters of the calcaneus, which enable to describe their respective joint integrity. The results show that only small intra-individual differences within the anatomy exist. Surgical treatment should take place with the aid of CT data from the contralateral side. Thus, a good restoration of the anatomy may be reached. The computational tool assesses the quality of reduction, and may be helpful to evaluate the outcome and quality of operative treatment based on the calculated joint-specific parameters of joint reconstructions in the hind foot. 相似文献
7.
The developmental study of the skull reveals the following views: The elapid chondrocranium represents a very advanced ophidian type. It more resembles the viperid chondrocranium than the colubrid one. The viperid chondrocranium is only very slightly more advanced than that of the Elapidae. The viperid osteocranium has progressed still further in the development of the poison apparatus than has the elapid osteocranium. The developmental study of the skull advocates the opinion that the family Colubridae has given rise to the family Elapidae, and the Elapidae (or at least the ancestral Elapidae) has given rise to the family Viperidae. 相似文献
8.
G Bogusch 《Acta anatomica》1987,129(4):275-278
The dorsal rami of the cervical and thoracic spinal nerves were investigated using both the in situ cholinesterase staining technique and cholinesterase staining on serial sections of plastic-embedded embryos. In most cases only the dorsal rami of the 2nd to 5th cervical spinal nerve possess cutaneous branches. The area innervated by the cutaneous branch of the dorsal ramus of the 5th spinal nerve borders on an area innervated by the cutaneous branch of the dorsal ramus of the 1st thoracic spinal nerve. The dorsal rami of the cervical spinal nerves 6-8 show no cutaneous branches. Therefore the gap in the series of the dorsal cutaneous branches is due only to the middle part of the nerves of the brachial plexus, which range from the 5th cervical nerve to the 1st thoracic nerve. 相似文献
9.
An autoradiographic study of the distribution of fibers from the dorsal motor nucleus of the vagus to the digestive tube of the rat 总被引:1,自引:0,他引:1
At the present time, complete agreement on the origin and course of parasympathetic preganglionic fibers to the alimentary canal has not been reached. The purpose of this study was to trace vagal fibers to the abdominal cavity and to follow the distribution of these fibers to the digestive tube. The technique used was to label neurons in the dorsal motor nucleus of the vagus (DMX) with 3H-leucine and then to follow the orthograde transport. 16 albino rats were used in this experiment. The right DMX in one group of rats and the left DMX in the other group was injected with 25 microCi of 3H-leucine in three injections. The injection sites and tissue sections from various areas of the digestive tube were processed for autoradiography. A heavy label was observed in the injection site and it could be traced down the vagus nerve through the thorax into the abdomen. Labelled vagal fibers were found in the parasympathetic ganglia of the stomach, small intestine and colon. 相似文献
10.
Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418 相似文献
11.
《Review of Palaeobotany and Palynology》1986,48(4):327-345
The paper presents results of miospore studies on Carboniferous strata from drillings made in the last 20 years in several regions in marginal zones of the East-European Platform in Poland (Lublin Coal Basin, Warsaw, Płock, and Bydgoszcz regions, and western Pomerania). In that area the Carboniferous is represented by Dinantian and Silesian strata, from the Tournaisian to Westphalian D.Because of differences in geological development of the Carboniferous and in composition of microfloristic assemblages from strata of that age in the above mentioned regions the first stage of the studies had to be aimed at compilation of local palynostratigraphic schemes for individual regions. The next stage involved compilation of a regional palynostratigraphic scheme for the whole area of Polish margin of the East-European Platform. The scheme comprises 16 spore zones of the concurrent-range-zone type: 6 for the Dinantian and 10 for Silesian. The detailed characteristics of miospore assemblages and age correlations of the zones are given.The proposed scheme was subsequently compared with that proposed for the Carboniferous in western Europe. The comparison showed marked similarities in ranges of taxa diagnostic for individual stratigraphic units in both schemes. 相似文献
12.
E V Sabaneeva 《Tsitologiia》1988,30(12):1395-1401
The review is dedicated to the question, to what extent it is possible to speak about the correspondence of the fibrillar center (FC) of the nucleolus to the nucleolar organizer region (NOR) of the metaphase chromosome. The analysis of the literature on the problem provides grounds for the affirmation that the chromatin-containing elements of the FC and of the fibrillar component of the nucleolus correspond to the NOR. At the same time, the number of facts evidence in favour of the hypothesis that the FC serves as a kind of "depot" for nucleolar proteins. The latter makes it possible to consider the FC to be polyfunctional. 相似文献
13.
The unambiguous assignment of the nuclear magnetic resonance (NMR) signals of the alpha-substituents of the haems in the tetrahaem cytochrome isolated from Shewanella frigidimarina NCIMB400, was made using a combination of homonuclear and heteronuclear experiments. The paramagnetic (13)C shifts of the nuclei directly bound to the porphyrin of each haem group were analysed in the framework of a model for the haem electronic structure. The analysis yields g-tensors for each haem, which allowed the assignment of some electron paramagnetic resonance (EPR) signals to specific haems, and the orientation of the magnetic axes relative to each haem to be established. The orientation of the axial ligands of the haems was determined semi-empirically from the NMR data, and the structural results were compared with those of the homologous tetrahaem cytochrome from Shewanella oneidensis MR-1 showing significant similarities between the two proteins. 相似文献
14.
G D Burde? 《Arkhiv anatomii, gistologii i émbriologii》1985,88(6):25-28
The spinal cord in 25 non-inbred dogs has been studied macro-microscopically. The dissymmetry in the arrangement level in the right and left root bases on the dorsal surface of the spinal cord is much greater than on the ventral surface. The same as in the human being, the dissymmetry is the greatest in the thoracic part (as compared to other spinal parts). On the ventral surface of the spinal cord both along the anterior and posterior margin of the root bases, there is a right-sided dissymmetry (with cranial shift); on the dorsal surface it is present only at the roots along the posterior margin. The dissymmetry of the dog spinal cord is quantitatively estimated along its whole extension. 相似文献
15.
Z M Drozdovski? 《Arkhiv anatomii, gistologii i émbriologii》1977,73(9):88-94
The figure of tetrahedron is formed in certain species of Plectus and in Tobrilus gracilis at the stage of 4 blastomeres rather than a rhombus which is formed in most highly organized nematodes. The analysis of the Nematoda's embryogenesis allows to conclude that tetrahedron, rhombus as well as some other figures play the role of preblastula sustaining the most expedient disposition of the first blastomers for transition to the formation of the blastula. With the increasing organization of nematodas the tetrahedron preblastula turns into a rhombic, linear-rhombic and at last in aphelenchoid-tylenchoid one. The character of the distribution of structural elements of organs and tissues of the definitive animal in the cytoplasm of the egg of Plectus and Tobrilus confirms the rightness of the division of the class of nematodas into subclasses Enoplia and Chromadoria rather than subclasses Adenophorea and Secernentea. 相似文献
16.
Localization of the kdsA gene with the aid of the physical map of the Escherichia coli chromosome 总被引:5,自引:3,他引:2
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The isolation and analysis of two recombinant plasmids containing the kdsA gene from Escherichia coli chromosomal gene libraries is reported. The subfragments obtained from the inserts correspond to the fragment pattern around coordinate 1,282 kilobases of the physical map of the E. coli chromosome (Kohara et al. Cell 50:495-508, 1987). The kdsA gene has been located at coordinates 1,282 through 1,283 kilobases, corresponding to min 26.7 in the classical map coordinates. The kdsA gene is transcribed from this position toward the nearby nar gene. 相似文献
17.
Panova IG Sharova NP Dmitrieva SB Levin PP Tatikolov AS 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2008,151(4):676-681
This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed. 相似文献
18.
The activity and spectrum of proteinases in the intestines of host fishes change upon infestation with cestodes. Serine proteinases are found to make a greater contribution to the total proteolytic activity. The reduction of proteolytic activity is associated with adsorption of the enzymes of the host on the surface of cestodes, and the increase in the activity is caused by the injury of the intestinal mucosa by the attachment apparatuses of cestodes. The inhibition of proteainase activity indicates the possible participation of microbiota enzymes in protein hydrolyses. 相似文献
19.
Previous electron microscope studies have shown that the Schwann cell layer is traversed by long and tortuous slit-like channels ~60Å wide, which provide the major route of access to the axolemma surface. In the present work the restriction offered by the resting axolemma to the passage of six small non-electrolyte molecules has been determined. The radii of the probing molecules were estimated from constructed molecular models. The ability of the axolemma to discriminate between the solvent (water) and each probing molecule was expressed in terms of the reflection coefficient σ. σ was then used to calculate an effective pore size for the resting axolemma. The value of 4.25 Å found for the pore radius is in excellent agreement with the 1.5 to 8.5 Å limiting values previously calculated from our measurements of water fluxes. The presence of pores with 4.25 Å radius in the resting axolemma is compatible with restricted diffusion of Na. The present paper leads to the conclusion that the axolemma is the only continuous barrier across which the ionic gradient responsible for the normal functioning of the nerve can be maintained. The combined findings of electron microscopy, water permeability, and molecular restricted filtration indicate that in all probability the axolemma is the "excitable membrane" of the physiologists. 相似文献
20.
N A Dmitrieva 《Tsitologiia》1986,28(7):745-748
The developing taste buds of vallate papillae were studied with electron microscope in rats during the first 7 days after birth. Two types of cells--light and dark--are identified in the taste buds of a one day old animal. The apical parts of dark cells are characterized by numerous dark granules. A distinguishing feature of light cells is the presence of synaptic contacts with afferent intragemmal nerves. On the 4th day of development on the top of the apical parts of the cell, a microvillar apparatus is seen to form, which does not yet communicate with the oral cavity. On the 7th day, basal cells appear in the taste buds. Some of these cells are seen mitotically dividing. The differentiated microvillar apparatus now communicates with oral cavity. The structure of the taste buds is getting similar to that in the adults. The structural and functional peculiarities of the developing taste buds are discussed in association with the period of ontogenesis under consideration. 相似文献