首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The peculiarities of reactions of blood capillaries and their cell structures in the ovary of 20-days old foetus to the irradiation in embryogenesis were revealed; it was shown for the first time that the character and direction of changes in principal morphofunctional parameters depended on the dosage, power of gamma-irradiation and the age of the developing organism by the exposure moment.  相似文献   

2.
The bronchial ramification and lobular division in lungs of two chimpanzees (Pan troglodytes) were examined from the viewpoint of comparative anatomy, on the basis of the fundamental structure of bronchial ramification of the mammalian lung (Nakakuki, 1975, 1980). The right lung of the chimpanzee consists of the upper, middle, and lower lobes, whereas the left lung consists of the middle and lower lobes. The right and left lungs have the dorsal bronchiole system, lateral bronchiole system, and medial bronchiole system. The ventral bronchiole system is lacking on both sides. The right upper lobe is formed by the first branch of the dorsal bronchiole system. The right middle lobe is formed by the first branch of the lateral bronchiole system, and the right accessory lobe bronchiole is lacking. The remaining bronchioles constitute the right lower lobe. In the left lung, the upper and accessory lobes are lacking. The well developed middle lobe is formed by the first branch of the lateral bronchiole system. The left lower lobe is formed by the remaining bronchioles. Furthermore, these bronchioles are compared with those of the human lung byBoyden (1955).  相似文献   

3.
The bronchial tree and lobular division of the lungs of four white handed gibbons (Hylobates agilis) were examined from the viewpoint of comparative anatomy, based upon the fundamental structure of the bronchial ramifications of the mammalian lung (Nakakuki, 1975, 1980). The right lung of the white handed gibbon consists of the upper, middle, lower, and accessory lobes, whereas the left lung consists of the middle and lower lobes. Each lobe is separated by the interlobular fissure, on both sides. The right and left lungs have the dorsal bronchiole system, lateral bronchiole system, and ventral bronchiole system. The medial bronchiole system is lacking on both sides. In the right lung, the upper lobe is formed by the first branch of the dorsal bronchiole system. The middle lobe is formed by the first brach of the lateral bronchiole system, and the accessory lobe by the first branch of the ventral bronchiole system. The remaining bronchioles constitute the right lower lobe. In the left lung, the upper lobe bronchiole, which is the first branch of the dorsal bronchiole system, is lacking. Therefore, the middle lobe bronchiole, i.e. the first branch of the lateral bronchiole system, is well developed. The accessory lobe bronchiole, the first branch of the ventral bronchiole system, is also lacking. The remaining bronchioles constitute the left lower lobe. These features were compared with those of other apes and man.  相似文献   

4.
The bronchial, arterial, and venous trees of the lung are complex interwoven structures. Their geometries are created during fetal development through common processes of branching morphogenesis. Insights from fractal geometry suggest that these extensively arborizing trees may be created through simple recursive rules. Mathematical models of Turing have demonstrated how only a few proteins could interact to direct this branching morphogenesis. Development of the airway and vascular trees could, therefore, be considered an example of emergent behavior as complex structures are created from the interaction of only a few processes. However, unlike inanimate emergent structures, the geometries of the airway and vascular trees are highly stereotyped. This review will integrate the concepts of emergence, fractals, and evolution to demonstrate how the complex branching geometries of the airway and vascular trees are ideally suited for gas exchange in the lung. The review will also speculate on how the heterogeneity of blood flow and ventilation created by the vascular and airway trees is overcome through their coordinated construction during fetal development.  相似文献   

5.
The comparative histological and morphometric analysis of the bronchial structures of human fetal lungs was performed. Fetal lungs were taken from pregnant women living in radionuclide polluted zones (Novozibcov, Bryansk region) or in control regions (Moscow) in different periods after Chernobyl accident. Relative areas of the bronchial epithelial tubes and mesenchyme, quantity of bronchial branches and buds (end sections) of epithelial tubes on cut area unit were determined. The dates received in 1992-1993 showed the delay of fetal bronchial growth and branching in comparison with control. It can be estimated as tissue dysplasia of lungs from fetuses of mothers living in Novozibcov. The material received in 1995 showed the more intensive growth of bronchial branches in human fetal lungs than the material from Novozibcov and of the Moscow control, taken in 1992-1993. These date suggest the heterogenous character of lung prenatal morphogenesis reactions of offspring from pregnant women lived in different periods on controllable territories of Bryansk region.  相似文献   

6.
Lung tissue restructuration is one of the most important components of chronic pneumopathies. Comparison of experimental and human data regarding the dynamic evolution of variously induced chronic lung processes pointed out as main mechanisms the bronchial and bronchiolar obstructions, the viral and fungal pneumonitic processes, the parenchymatous suppurative processes, the granulomatous organization of cellular reactions, the interlobular cell accumulations, the hypersensitivity reactions, and the lesions of small vessels. Mostly acting in association, these dynamic conditions determine the fibroplastic transformation of lesions, the exclusion of unventilated areas, the destruction of respiratory surfaces, the clear predominance of connective tissue structures, sometimes with ossifications; some microcavities persist within restructuring areas, sometimes delimited by alveolar or bronchiolar epithelia. The honeycomb lung is one of the evolutive possibilities of this restructuration of damaged tissues during chronic lung diseases.  相似文献   

7.
We studied cell-specific protein expression of all the major antioxidant enzymes (AOEs) and related proteins, such as copper-zinc superoxide dismutase (CuZnSOD), manganese SOD (MnSOD), extracellular SOD (ECSOD), catalase, the heavy and light chains of gamma-glutamylcysteine synthetase (gamma-GCS-l and gamma-GCS-h, also called glutamate cysteine ligase), the rate-limiting enzyme in glutathione synthesis, hemeoxygenase-1 (HO-1), and thioredoxin (Trx), in developing human lung, respiratory distress syndrome, and bronchopulmonary dysplasia by immunohistochemistry. Generally, after 17 weeks of gestational age, MnSOD was predominantly expressed in bronchial epithelium, alveolar epithelium, and macrophages, CuZnSOD was expressed in bronchial epithelium, ECSOD was expressed in bronchial epithelium, vascular endothelium, and the extracellular matrix, catalase was expressed in bronchial epithelium and alveolar macrophages, gamma-GCS-h was expressed in bronchial epithelium and endothelium, and gamma-GCS-l was expressed in bronchial epithelium. Trx was restricted to bronchial epithelium and to a lesser extent to alveolar macrophages, and HO-1 found in alveolar macrophages. Basically, the expression of these enzymes was similar in normal and diseased lung. It can be concluded that various AOEs and related proteins differ in their distribution and expression in lung before term, but generally it seems that infants are better adapted to high oxygen tension than might be expected.  相似文献   

8.
The enzyme PAM is required for activation of many peptide hormones. In adult mouse lung, immunostaining for PAM was located in Clara cells, which constitute most of the epithelial cells of the mouse bronchial/bronchiolar tree. Immunoreactivity appeared for the first time in the epithelium on gestational Day 16, being slight and mostly restricted to the apical cytoplasm. As the lung developed, the labeling became gradually stronger and extended throughout the cell. Smooth muscle of airways and blood vessels, and some parenchymal cells, probably macrophages, also showed PAM immunoreactivity. Of the two enzymatically active domains of PAM, only PHM and not PAL immunoreactivity was found at all stages studied. The early appearance of PAM in developing mouse lung, as well as its presence in a variety of tissues, probably indicates a complex role of this enzyme in pulmonary development and function.  相似文献   

9.
Discrepancies exist between experimental measurements of the systemic blood flow to sheep lung by use of microsphere techniques and flow probes on the bronchial artery. In these studies, we simultaneously measured the blood flow through the bronchial artery, using a transit time flow probe, and the systemic blood flow to left lung, using radioactive microspheres. All measurements were made on conscious sheep previously prepared with chronic catheterizations of the left atrium, aorta, and vena cava and a flow probe around the bronchial artery. Inflatable occluder cuffs were placed around the pulmonary and bronchoesophageal arteries. Bronchial artery blood flow in six sheep was 25.3 +/- 5.2 ml/min or 0.4% of the cardiac output. Systemic blood flow to left lung, measured with microspheres, was 54.1 +/- 14.2 ml/min. Calculated systemic blood flow to that portion of sheep lung perfused by the bronchial artery was 127.6 +/- 35.3 ml/min or 1.9% of cardiac output. Occlusion of the bronchoesophageal artery reduced bronchial artery flow to near zero, whereas total systemic blood to the lung was reduced by only 55%. Blood flow to the intraparenchymal cartilaginous airways was reduced 60-90% after occlusion of the bronchoesophageal artery. Sheep, like most mammals, have multiple and complex systemic arterial inputs to the lungs. We conclude that multiple branches of the bronchoesophageal artery provide most but not all of the systemic blood flow to the intraparenchymal cartilaginous airways but that over one-half of the total systemic blood flow to sheep lung comes from sources other than the common bronchial artery.  相似文献   

10.
Hakata antigen was first reported as a serum protein that reacted with an autoantibody from patients with systemic lupus erythematosus. Recently, it has been found that Hakata antigen is a new member of the ficolin/opsonin p35 family, which is a distinct lectin family, on the basis of homology of structures and the common characteristic of possessing lectin activity. In this study we analyzed the tissue distribution of Hakata antigen. Hakata antigen mRNA and protein were generated in the lung and liver. In the lung, Hakata antigen was produced by both ciliated bronchial epithelial cells and Type II alveolar epithelial cells and was secreted into the bronchus and alveolus. In the liver, Hakata antigen was produced by bile duct epithelial cells and hepatocytes and was also secreted into the bile duct. These results demonstrate that Hakata antigen is a unique lectin protein that exists not only in serum but also in bronchus/alveolus and bile, and indicate that Hakata antigen plays a role in bronchus/alveolus and bile under physiological conditions.  相似文献   

11.
A systemic approach to the pulmonary lobule in health and disease is attempted. There are emphasized the lobule definition, structure and functions (respiratory, metabolic, defensive), the program of lobular structures, their relation ways, their capacity of growth and regeneration, all contributing to the relative independence and autonomy of pulmonary lobules and to their behaviour as wholes. Taking into account the characters of pulmonary lobules in health, their pathological involvement is analysed on human and experimental materials, pointing out the importance of the aerogenic component of pathogenesis in determining the first phases of lung diseases, and of the true pulmonary characters of lesions, in comparison with those induced by the parenteral penetration of agents.  相似文献   

12.
The up-to-date data on mitochondrial tRNAs of yeast, their structures and peculiarities of these structures, anomalies of the mitochondrial genetic code and anticodons of tRNAs, the structure and number of tRNA genes are reviewed in the present paper. New information concerning 17 types of yeast mitochondrial tRNAs, deciphered by the authors of the paper are given; among them 8 types are first published. The likeness and differences of yeast mitochondrial tRNAs from their cytoplasmic counterparts are discussed by comparison with other organisms.  相似文献   

13.
Lung resistance-related protein (LRP) is an integral part of the multidrug resistance (MDR) phenotype involved in cell resistance toward xenobiotics or chemotherapy. The aim of this study was to compare the intracellular localization and cell expression of LRP in normal bronchial cells and their tumoral counterparts from non-small cell lung cancer (NSCLC). LRP expression was also investigated concurrently with DNA ploidy and chromosome 16 (lrp gene locus) aberrations. Confocal microscopy showed that LRP localization was exclusively intracytoplasmic regardless of the cell type and was never observed in the nuclear pore complex. Flow cytometry demonstrated a similar level of LRP expression in normal bronchial cells and in cancer cells from NSCLC samples. FISH analysis, performed to evaluate the number of chromosome 16 and lrp loci, demonstrated a significant gain of chromosome 16 in DNA aneuploid tumors. Furthermore, we did not find any link between LRP expression and DNA ploidy status or chromosome 16 number. These results suggest that LRP expression observed in NSCLC, maintained through the carcinogenesis process of respiratory cells, is not altered by the increased number of copies of chromosome 16 and probably controlled by mechanisms different from those of MRP1 expression, whereas both proteins are associated with the MDR phenotype.  相似文献   

14.
Segmental mobility dynamic peculiarities of poly(U), poly(A) and poly(C) synthetic polymers and their complexes were investigated by spin-label method. Imidazolide spin-label was introduced into 2'-oxi-groups of polymer ribose in correlation: one spin-label on 18-20 bases. Formation of complexes was observed by ESR spectra at two pH: 4.2 and 7.2. Segmental mobility of only single strand spin-labelled polymer segment and in the complex was evaluated by measuring rotational correlation time (tau) determined by dependence of distances between outer wide extrema in ESR spectra from solvent viscosity at different temperatures. It turned out that correlation time tau of single strand structures in a high degree depend on pH and temperature. For three strand structures abrupt increase of tau because of appearance of rigidity was observed. It is possible to evaluate part of triple complexes poly(U.A.A) and poly(U.U.A) existing in dynamic equilibrium depending on pH and temperature by the form of outer wide extrema. Adding of dye to complex of poly(U).poly(A) causes an increase of rigidity of the supermolecular structure. Quantitative characteristics of formed complexes were obtained by simulation of ESR spectra on computer.  相似文献   

15.
Abstract

The Structural Heterogeneity of Plants with a Thallus. Plants that evolved in aquatic environments developed a thallus, that is a multicellular body without structures deputed to the mass transportation of water along great distances. The structural organisations of thalli shows a number of different solution to reach the coordination necessary to the expression of differentiation in the multicellular thalli. Some of these structures are comparatively esamined, pointing out their peculiarities. The diversity observed among plants evolved in aquatic environments is expressed not only by the taxa that can be recognized, but also by a great number of solutions developed to express the differentiation of parts in a complex multicellular body.  相似文献   

16.
The lobular division, bronchial tree, and blood vessels in lungs of seven squirrel monkeys (Saimiri sciureus) were examined from the viewpoint of comparative anatomy. The right lung of the squirrel monkey consists of the upper, middle, lower, and accessory lobes, whereas the left lung consists of the upper, middle, and lower lobes. These lobes are completely separated by interlobular fissures. In three of seven examples examined the left middle lobe was lacking. The squirrel monkey lung has four bronchiole systems, i.e. dorsal, lateral, ventral, and medial, on both sides. The upper lobes are formed by the first branches of the dorsal bronchiole systems. The middle lobes are formed by the first branches of the lateral bronchiole systems. The remaining bronchioles constitute the lower lobes. In addition to the above lobes, in the right lung, the accessory lobe is present, being formed by the first branch of the ventral bronchiole system. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole, and then across the dorsal side of the right middle lobe bronchiole. Thereafter, it runs between the dorsal bronchiole and lateral bronchiole systems along the dorso-lateral side of the right bronchus. During its course, the right pulmonary artery gives off the arterial branches which run along each bronchiole. These branches run mainly along the dorsal or lateral side of the bronchioles. In the left lung, the pulmonary artery and its branches run the same course as in the right lung. The pulmonary veins run mainly the ventral or medial side of the bronchioles, and between the bronchioles.  相似文献   

17.
The bronchial flow is approximately 1% of the total pulmonary flow. Anastomosis between the bronchial and pulmonary vessels occurs primarily at the microcirculatory level. It is assumed that bronchopulmonary anastomoses are present in a homogeneous manner throughout lung parenchyma. To investigate this issue, an in situ blood-perfused left lower lung lobe (500 ml/min) was prepared in a live dog. The bronchial flow rate in the entire lobe was monitored using the rate of volume gain in the reservoir while the pulmonary and bronchial flow in the subpleural region was monitored using laser-Doppler flowmetry. The results were expressed as ratio of bronchial to pulmonary flow rate for the entire lobe and for the subpleural region. We found that, for the entire lobe, bronchial flow was 1.0% of pulmonary flow, while for the subpleural region this ratio was much higher, with an average of 12%. In two different experimental conditions that were imposed to affect the global bronchial flow, these ratios changed in the same direction as the global bronchial flow. After transfusion of blood into the animal, bronchial flow increased to 1.7%, while the subpleural bronchial flow increased to 18% of the subpleural pulmonary flow. During elevation of venous pressure, bronchial flow decreased to 0.6%, while the subpleural bronchial flow decreased to 10% of the subpleural pulmonary flow. The differences in the ratios between the global and subpleural region may be explained by having low pulmonary blood flow in the periphery compared with the interior regions of the lung.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

18.
Expression of brain-associated small-cell lung cancer antigen (BASCA) in developing lung and in lung tumors was investigated immunohistochemically and immunoelectron microscopically with monoclonal antibodies recognizing different epitopes of BASCA. In fetal lung, epithelial and mesenchymal cells had different spatial and temporal expression patterns, in contrast to the consistent pattern in neural cells. The cell membranes of epithelial cells of the proximal bronchial tubes were diffusely positive at the pseudoglandular stage. Ciliated cells lost immunoreactivity shortly after their emergence, but non-ciliated cells, including endocrine cells, lost it at the alveolar stage. The immunoreactivity in mesenchymal cells was reduced in the proximal airway, but positivity remained in the distal lung later during the postnatal period. All endocrine tumors of the lung, defined by diffuse synaptophysin immunoreactivity, expressed BASCA, but some non-endocrine carcinomas which also lacked densely cored granules ultrastructurally, showed BASCA positivity. The temporal and spatial pattern of BASCA expression in the developing lung suggests that BASCA plays an active role in lung morphogenesis. BASCA may be expressed as an oncofetal substance in some non-endocrine carcinomas of the lung.  相似文献   

19.
An antiserum that specifically recognizes a lung-specific antigen present in the great alveolar cell in the adult mouse lung was used in immunofluorescence studies to detect the first appearance of this antigen in the embryo. Cellular fluorescence was found to occur in the lung tissue from about Day 14.2 onward and to be due to the presence of the lung-specific or a related antigen. The simultaneous appearance of this antigen (ca. Day 14.2) and the cuboidal type of epithelial cell in which it occurs (ca. Day 14) means that the great alveolar cell—or its precursor—is first detectable around Day 14.2. Since the great alveolar cell—or its precursor—is the first and only type of alveolar epithelial cell to occur in the embryonic lung, it must be the stem cell from which the small alveolar cell derives. The persistent sharp demarcation between the prospective alveolar and bronchial epithelia indicates that the respiratory and the conducting portions of the lung originate from different parts of the tubular system in the prenatal lung.  相似文献   

20.
Comparative microelectrophysiological study of character and peculiarities of effects of the cortical nucleus of amygdala and of the periamygdalar area of pyriform cortex on impulse activity was performed on the same single functionally identified respiratory medullar neurons. A high reactivity of bulbar respiratory neurons on stimulation is established in both studied limbic structures. There is established the qualitatively different character of their response reactions at stimulation of the cortical amygdala nucleus and the periamygdalar cortex. The cortical amygdala nucleus has been shown to produce on the activity of medullar respiratory neurons both facilitating and inhibitory action with predominance of the activating one (without topographical orderliness). The effect of periamygdalar cortex at stimulation of various parts was characterized by topographic differentiation. The suppressing reactions of neurons in the majority of cases were recorded at stimulation of the rostral area of periamygdalar cortex, whereas the excitatory reactions--at stimulation of its caudal part. Functional organization of respiratory control of the studied limbic system structures is discussed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号