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1.
The electrophoretical polymorphisms of some blood proteins were studied in the Talysh population of Pirasora situated in South-East Azerbaidjan. We calculated the gene frequencies of these polymorphisms and determined the genetic distances between the Talyshes and some Iranian populations of North, Central and South Iran, Afghans, and three populations of Azerbaijan. The Talyshes are very close to Iranians of Shiraz, whereas they are distant from the Azerbaijanians. Anthropological investigations showed that the Caucasoids and Mongoloids lived in the Aragvi Basin since the Eneolithic period. This was stated by Alexeev (1974), who emphasized the mixture of the Caucasus populations from ancient times on. We calculated the genetic distances between the Caucasus populations and numerous populations of other geographic regions, considering 28 alleles of 12 loci of blood group, serum protein and red cell enzyme polymorphisms and constructed the dendrogram of these populations. The position of the Caucasus populations in the dendrogram corresponds on principle to the earlier anthropological observations. The clustering of the Caucasoid populations corresponds completely with anthropological and historical data, and supports our earlier hypothesis (Nazarova 1999) concerning the differentiation of Caucasoids, Northern Mongoloids and Amerinds from the populations, which inhabitated Asia in palaeolithic times.  相似文献   

2.
In order to analyze the complicated movements of the mandible as the open-closing movement and the protrusio are, it is useful to evaluate the basic kinematic principles and reduce them to simple technical constructions. Both the open-closing movement and the protrusio could be reduced to 4-bar links, which were used to simulate the movements with help of a computer. Besides, the polodes and the curves of points in the muscular attachments could be constructed. The 2 entirely different 4-bar links have 3 things in common: The resting system - cranium, the moving system - mandibula, and 1 of the 2 arms connecting these 2 systems - the ligamentum laterale. As this ligament is taut during movements it can be considered a "guiding ligament" representing 1 of the 3 determining components of the mandibular movements. The other of the 2 arms has no anatomical equivalent; this arm, however, is "replaced" by the 2 other determining components of the mandibular movements: the joint and the muscles. The curves, which the Caput mandibulae describes, are practically identical for the open-closing movement and the protrusio despite of the different 4-bar links and these curves exactly correspond to the Discus articularis, taut by the upper part of the M. pterygoideus lateralis. The muscles do not only just move the mandibula, but they are also the component, which can choose between the different mandibular movements. By means of the curves, which points in the muscular attachments describe, the function of the masticatory muscles could be analyzed exactly.  相似文献   

3.
The general analysis of infanticide distribution pattern in primate and human populations is given. The possibilities to use the sociobiological, ecological, psycho-analytical and structural-social approaches are considered to explain the infanticide functions in primates. The necessity of exact data concerning the sex, age and social position of both: killers and victims (victim's mothers either) is stressed, as well the estimation of social situation in the group in the period before the infanticide. The qualitative differences in infanticide mechanisms in lower monkeys, anthropoids and man is illustrated. It is proposed to differentiate the infanticide on the individual level and as a group social strategy. The probability of infanticide in hominid societies on the different stages of evolution is discussed.  相似文献   

4.
1. The incorporation of orotic acid and of uridine into total RNA was measured in vivo in liver and lung of the Syrian golden hamster. Specific activities of total acid-soluble UMP were measured in both organs. An estimation of the rate of RNA biosynthesis showed that hamster lung synthesizes RNA at about one-half of the rate of that of hamster liver. 2. The apparent K(m) and V(max.) values of a few enzymes involved in pyrimidine biosynthesis were measured in the 100000g supernatants of liver and lung. The apparent K(m) values were very similar in both organs. From the estimated V(max.,) it was concluded that hamster lung cells have less capacity to metabolize orotic acid than have liver cells. 3. A time-response and a dose-response study showed that actinomycin D inhibits pulmonary RNA synthesis as efficiently as hepatic RNA synthesis. 4. Protein synthesis, measured as the incorporation of leucine, was inhibited in both organs 30min after a dose of 2mg of cycloheximide/kg. The dose-response patterns were similar in both liver and lung 3h after cycloheximide. 5. It is concluded that RNA and protein synthesis in vivo in hamster lung are very similar to the corresponding reactions in liver. Alterations of RNA and protein synthesis by toxic agents can therefore be evaluated in lung with a similar approach to that used to study the pathological biochemistry of liver.  相似文献   

5.
The parotid and the principal and accessory submandibular glands of the little brown bat. Myotis lucifugus (Vespertilionidae), were examined using light microscopy and staining methods for mucosubstances. The parotid gland is a compound tubuloacinar seromucous gland. Parotid gland secretory cells contain both neutral and nonsulfated acidic mucosubstances. The principal and accessory submandibular glands are compound tubuloacinar mucus-secreting glands. They contain somewhat atypical mucus-secreting demilunar cells that often appear to be interspersed between mucous tubule cells. The mucous tubule cells in both the principal and accessory submandibular glands contain sulfonmucins. Demilunar cells of the principal submandibular gland contain moderate amounts of nonsulfated acidic mucosubstances, but the corresponding cells of the accessory submandibular gland contain considerable neutral mucosubstance with very little acid mucosubstance. Intercalated ducts composed of cuboidal or low columnar epithelial cells are present in all three glands. Striated ducts in all glands are composed of columnar cells whose apices bulge into the ductal lumina. Excretory ducts are composed of simple columnar epithelium, with occasional basal cells that suggest a possible pseudostratified nature. The cells of the excretory ducts also have bulging apices. All duct types contain apical cytoplasmic secretory material that is a periodic acid-Schiff positive, neutral mucosubstance. Ductal apical secretory material is more evident in intercalated and striated ducts than in excretory ducts.  相似文献   

6.
The Rhizocephala are considered to be monophyletic due to several synapomorphies in the ontogeny of the cndoparasitic phase. The various types of metamorphosis described in the Rhizocephala are discussed and compared to metamorphosis in the Cirripedia Thoracica and Acrothoracica. In males and females of the suborder Kentrogonida. the cyprid settles and metamorphoses into a new instar, in males the trichogen and in females the infective kentrogon. The kentrogon goes through yet another. incomplete moult associated with the development of the stylet. Within the three kentrogonidan families. the Iernaeodiscid-peltogastrid type of kentrogon differs from the sacculinid type in the mode of attachment to the host. in the complexity of internal anatomy. in the position and penetration of the stylet, and in whether or not the cyprid carapace must be shed prior to penetration of the stylet. In the Akentrogonida metamorphosis never results in a new instar. Where observed (Clistosaccidae and Thompsoniidae). both male and female cyprids settle and penetrate into their substrate (female parasite or new host) with one of the antennules. Using the antennule as a syringe. male cyprids inject spermatogonia while female cyprids injects embryonic cells developing into an endoparasite. By comparison with metamorphosis in the Cirripedia Thoracica and Acrothoracica it is concluded that the presence of a metamorphic moult leading to a post-cyprid instar is plesiomorphic and that the trichogon and kentrogon are homologous with the first metamorphosed juvenile in these outgroups. The abbreviated ontogeny in the Akentrogonida without metamorphic moult and post-cyprid larval instars is considered apomorphic. This contradicts the long-held supposition that the Akentrogonida are the most‘primitive’Rhizocephala and dovetails with new information that this suborder contains many advanced traits. Within the Kentrogonida. the lernacodiseid-peltogastrid type of kentrogon is considered more plesiomorphic than the sacculinid type, which resembles the clistosaccidthompsoniid type in having the antennules involved in the penetration process. The homologization of the kentrogon with a juvenile barnacle indicates that presence of a kentrogon is plesiomorphic within the Rhizocephala and that the Kentrogonida is paraphyletic.  相似文献   

7.
The purpose of this paper is twofold: (1) to review the reproductive systems of the pulmonates in order to determine the inherent trends displayed by this system in these animals. The different elements composing this system, especially those of the pallial region, are homologised and the functional aspects (s. 1.) of the components described, including the origin and evolutionary development of the various prostatic elements of the pulmonates; and (2) to review ideas on and discuss the origin of the hermaphroditism of the pulmonate reproductive systems.  相似文献   

8.
In 186 roentgenograms of frontal projections, obtained in children from birth up to 7 years of age, made according to the vital indications (but without any pathology in the thoracic organs), and in 63 isolated preparation of lungs, skeletotopy and size of the lung roots have been studied. The skeletopic difference between superior and inferior margins of the roots near the medial surface of the lung in the newborns during the first day of life has been stated to make in the projection to the frontal thoracic wall 2 ribs, or 2 vertebrae (to the posterior wall), and to the end of the first month of life-3 ribs, or 3 vertebrae, respectively; during the first year-2.5 ribs, or 2 vertebrae, in children of 1-7 years of age-2 ribs, or 2 vertebrae, respectively. The projection borders of the lung roots from birth up to 7 years of age are noted to change in time and with various intensity.  相似文献   

9.
A contribution to knowledge of the compartments and the fascial and septal formations of the popliteal fossa in the human fetus and the adult. A study was made in human fetuses from the 3rd month onwards, newborn and the adult of the fascial and septal formations and the compartments of the popliteal fossa. Observations of serial sections of the knee of human fetuses, of macroscopic preparations of the knee of newborns and of ultrasound images of the popliteal fossa in adults showed that: the fascial formation covering the popliteal fossa consists of the popliteal fascia and the superficial fascia. The bud of the popliteal fascia is observable in the 3-month fetus as a layer of thin fibrillar connective tissue which is thicker in the tracts between the muscle buds. At birth the popliteal fascia is clearly a separate anatomical entity of continuous laminar structure which is thicker in the tracts between the muscles and thinner where it covers them. The superficial fascia becomes evident in fetuses at a later stage (6th month) in the form of a thin lamina in the frontal plane which at birth is well defined and observable as a thin continuous line deep below the subcutaneous layer. The septal formation consists of four septa: two in the sagittal plane (lateral and medial) and two in the frontal plane (lateral and medial). The bud of these septa appears in 4-month fetuses after the appearance of the popliteal fascia. They branch off from the thicker connective areas between the muscles buds as connective prolongations which later assume a laminar aspect and eventually become compact and form septa. In at-term fetuses and newborns these septal formations are clearly recognizable as antomical entities, which branch off from the deep surface of the thicker tracts of the popliteal fascia and are inserted into the femur. The relationships and connections with the muscular groups are also clearly visible. The organization and demarcation of the compartments, which is already delineated in the 6-month fetus, seems to be completed at birth, considering the presence of the superficial fascia, the popliteal fascia and the septa. It is possible to distinguish a superficial compartment between the popliteal and the superficial fascia an a deep compartment between the frontal septa, the skeletal plane and the popliteal fascia. This deep compartment is clearly subdivided by the two sagittal septa into three sectors (medial, intermediate and lateral). The medial and lateral sectors contain muscles, while the intermediate compartment contains the vasculonervous bundle and the popliteal adipose body.  相似文献   

10.
The density of the reticular and respiratory neurones in the inspiratory and the exspiratory "points" of medial and lateral zones of the medulla oblongata the electrical stimulation of which is accompanied by the maximum inspiratory and exspiratory effects has been studied in the anesthetized cats. The electrophysiological and morphological data allow to relate the structures studied to the respiratory centre and confirm the correct picking out of two functionally heterogeneous zones - the medial and lateral.  相似文献   

11.
The review of own and literature data devoted to structural and neurochemical organization of the nucleus accumbens (Acc) as well as spatial organization of their projection fibers in comparison with nucleus caudatus (neostriatum) has been presented. The facts concerned with correlations revealed between both the cell clusters and histochemical compartments as well as the compartmental organization of afferent and efferent striatal connections were analyzed. The presented data propose the existence of sensorimotor and limbic parts of the dorsal and ventral striatum, which are involved in the parallelly functioning systems. The common and different signs of these two systems and its role in the regulation of the movement behaviour has been proposed. A lot of attention also was payed to the Acc and the neostriatum interaction. The many pathways by which Acc can influence neostriatum functions and therefore the motor activity controlled by the neostriatum are discussed. It was shown that the Acc can influence on the striatal synaptic DA release. The sign of this influence depended upon DA/glutamic acid interactions in the Acc. It was stressed that the influence of Acc on striatal DA-ergic system is very likely mediated via kainate/quisqualate (but not NMDA) inputs of the neostriatum. The balance of DA-ergic mechanisms of neostriatum and Acc as important basis of animals adequate behaviour in conditioning situation was proposed. The disbalance of these mechanisms could leads to pathology.  相似文献   

12.
Measurements were made of the osmotic pressure of plasma, and of aqueous humor taken from the anterior chamber of the right and left eyes and from the posterior chamber of unanesthetized rabbits. Aqueous humor from the anterior chamber was found to be hypertonic to the plasma by approximately 3 mM/liter equivalent of sodium chloride. The aqueous humor from the anterior and posterior chambers of the right and left eyes was isotonic. The concentration of chloride in the anterior and posterior chambers was the same. The concentration of all the major components of the aqueous humor and plasma has been determined by chemical analysis on fluid samples obtained from unanesthetized rabbits at approximately the same time. The calculated osmotic pressure of the total of these substances in terms of sodium chloride equivalent agrees to within better than 1 per cent of the total osmotic pressure as measured experimentally. The distribution of some individual anions and cations of the aqueous humor and plasma was determined. This distribution is widely different from that which would obtain at a state of equilibrium. The positive and negative charges carried by the ions in the aqueous humor were approximately equal. Sources of error in the experiments are discussed.  相似文献   

13.
The effects of a synthetic antioxidant ionol (dibunol) on the biosynthesis and content of catecholamines in the heart and adrenal glands were studied. It was shown that in stress a mobilization of catecholamine reserve is combined with a considerable increase in dopamine concentration. In conditions of physiological rest, ionol did not affect the studied indices of adrenal catecholamine biosynthesis, while in the heart it enhanced the dopamine synthesis and content. With ionol administration, stress did not suppress but, on the contrary, increased the neuronal uptake and noradrenaline biosynthesis, catecholamine concentration remaining practically unchanged. Simultaneously, a manyfold increase in the biosynthesis along with a considerable increase in the concentration of dopamine developed in both organs. The data obtained suggest that ionol realizes its stress-defensive effect to a great extent due to the activation of catecholamine biosynthesis and to a concomitant increase in dopamine accumulation.  相似文献   

14.
On the origin of the Hirudinea and the demise of the Oligochaeta   总被引:10,自引:0,他引:10  
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates.  相似文献   

15.
Histological and histochemical methods were used to study the ovaries of Greenland seal (Pagophoca groenlandica) from birth-time up to 30 years of age and mature females of Phoca vitulina and Erignathus barbatus. The ovary of the new-born Greenland seal has fetal medullary substance which is a provisory endocrinous gland producing not only sex hormones but also corticosteron. In other species of seals the intestinal cells of the medullary substance are the equivalent of this gland. Within 3-4 weeks after birth the reduction of the fetal medullary substance is completed, it is substituted by the connective tissue and the ovary acquires its typical structure. The rest of the fetal medullary substance is in the depth of the cortex and near the infundibulum of the ovary as lipofuscincontaining cells. When the maturation period approaches, the process of the follicle atresia regularly changes: the epithelium dies quicker, and the multiplication of intestinal cells increases. The ovaries of seals are rich in interstitial cells. Their amount cyclically changes. The cells producing steroid hormones always well hydrolize AS naphthyl-phosphates, the reaction with glycerophosphate is more variable. The connective tissue is poor in acid mucopolysaccharides, its amorphous substance in the ovary cortex is rich in protein. Senile changes of the ovary are noticed in the seal beginning from 20 years of age.  相似文献   

16.
Abstract Earlier papers dealing with the anatomy of the hesionids and syllids were studied. Thereby it was found that information about the structure of the central nervous system was meagre. As a result, the anterior end appendages, especially the large, laterloventral ones of the Syllidae, have been differently interpreted. This prompted a re-investigation. The circum-oesophageal connectives, the brain commissures and the innervation of the alimentary canal and the cephalic appendages of a number of hesionid and syllid species were studied. The results, summarized in schematic diagrams, were compared with corresponding observations in other polychaete families. Among other things, it was concluded that not only the latero-ventral cephalic appendages of the hesionids but also those of the syllids are homologous with the palps of the nereids and of many other “errant” and “sedentary” families.  相似文献   

17.
In acid and alkaline media, glycolaldehyde (hydroxyacetaldehyde) exists in equilibrium with its enediol form, which is quantitatively oxidized to glyoxal by an excess of Methylene Blue. In acid and alkaline media, the enol form of methoxyacetaldehyde is formed. In alkaline medium, this enol is stable; in acid, it undergoes hydrolysis to glycolaldehyde. The kinetics of enolization of glycolaldehyde methoxyacetaldehyde were studied polarographically. The mechanisms of enolization of glycolaldehyde and acid hydrolysis of methoxyacetaldehyde were established both from kinetic data and from deuterium-incorporation data. The proposed mechanisms were confirmed by quantum-mechanical calculation of the charge distribution in the two compounds studied and their reaction intermediates. The glyoxal obtained in the oxidation was isolated as quinoxaline and analyzed by mass spectrometry.  相似文献   

18.

Background  

This paper is an attempt to trace the evolution of the ribosome through the evolution of the universal P-loop GTPases that are involved with the ribosome in translation and with the attachment of the ribosome to the membrane. The GTPases involved in translation in Bacteria/Archaea are the elongation factors EFTu/EF1, the initiation factors IF2/aeIF5b + aeIF2, and the elongation factors EFG/EF2. All of these GTPases also contain the OB fold also found in the non GTPase IF1 involved in initiation. The GTPase involved in the signal recognition particle in most Bacteria and Archaea is SRP54.  相似文献   

19.
This study was undertaken to examine further the behavior of the Hre gene and its interaction with the growth and reproduction complex genes (grc) in the (Hre x BN)F2, Hre x (Hre x BN)F1 and (BIL/1 x Hre) F2 crosses. The blaze characteristic of rats carrying the Hre gene was linked to testicular weight but not to the body weight or to the major histocompatibility complex (MHC). The Hre defect was genetically unrelated to the testicular defect caused by the grc. The Hre gene had a variable effect on the testes of the rats in different crosses, and it could be categorized into three distinct stages of progressively greater severity. In the cross in which the parents carried the Hre/+ and grc/grc genes, respectively, there was a decreased litter size, an increased male:female ratio in the offspring and poor reproductive performance when compared to a similar cross in which the Hre/+ gene alone was segregating. There was, however, no effect on the severity of the testicular defect. Thus, the grc can interact with the Hre gene to cause embryonic death, which appears to be selective for females, but not to influence the severity of the testicular defect.  相似文献   

20.
The capillary volumes in the endocrine and exocrine parenchyma of the pancreas were compared with a point-sampling technique. The islets were found to have a capillary volume of approximately 3.5%, while the value for the exocrine pancreas was significantly (P less than 0.001) lower at 2%. When the capillary wall area was measured, however, both types of parenchyma had a similar value of approximately 20 mm2/mm3 tissue. The reason for the discrepancy between these parameters is probably the lack of lymphatic capillaries, with their relatively small lumen in the islets.  相似文献   

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