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1.
Proper glands in 248 total preparations and lymphoid accumulations in 112 preparations have been investigated macro-microscopically in the human oesophageal preparations at various age. The organs have been obtained from 152 corpses of persons died from the death by violence and having no pathological changes in the organs of digestive and immune systems. The lymphoid tissue in the oesophageal wall is presented as accumulations of cells (prenodules++) and as diffusely scattered immune-competent cells. The glands and lymphoid accumulations are oriented as longitudinal rows. The lymphoid tissue accumulations are situated near to the glandular ducts, because the latter can serve as pathways for penetrating antigenic material into the organ's wall. The amount of the glands is maximal mature and elderly age, and that of lymphoid accumulations--at the second childhood. The dimensions of the gland body increase in the cranio-caudal direction, while the lymphoid accumulations, just the reverse, have their maximal dimensions in the upper third of the oesophagus. The gland bodies in places of the organ's anatomical narrowings in the section have more alveoles and are situated nearer to the covering epithelium than the glands in the neighbouring areas of the wall.  相似文献   

2.
Responsiveness of norepinephrine (NE)-sensitive cyclic AMP (cAMP)-generating systems was determined in slices from different areas of the rat cerebral cortex in which FeCl2 solution was injected unilaterally into the sensorimotor cortex to induce epileptic activity. In anterior cortical areas of rats in which the appearance of electrographic isolated spikes was dominant either ipsilaterally or contralaterally to the injection site 8-10 days after the injection, the cAMP accumulations elicited by NE and an NE-phentolamine combination were greater on the side of dominant spike activity than on the other. In anterior cortical areas of rats showing dominant spike activity on either side of the cortex 31-60 days after the injection, the cAMP accumulation elicited by NE was smaller on the dominant side than on the other. In anterior cortical areas of rats showing nearly equal spike activity on the two sides 31-60 days after the injection, the cAMP accumulations elicited by NE and an NE-phentolamine combination were greater on the side ipsilateral to the injection site than on the other. In anterior and posterior cortical areas of rats in which the appearance of spike and wave complexes, as well as isolated spikes, was detected 31-60 days after the injection, the cAMP accumulations elicited by NE and combinations of NE and phentolamine or propranolol were greater on the side ipsilateral to the injection site than on the other. The elicitation by an NE-propranolol combination, but not by an NE-phentolamine combination, of cAMP accumulation was almost completely inhibited by 8-phenyltheophylline.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
K. Hausmann  B. Walz 《Protoplasma》1979,99(1-2):67-77
Summary In the cytoplasm of the marine ciliateEuplotes vannus, there exist two conspicuous types of membrane bound inclusions: 1. irregularly shaped crystals which are highly anisotropic; 2. globular lithosomes characterized by concentrically arranged layers of deposits which exhibit only faint birefringence. Normally, both structures form distinct accumulations. Energy dispersive X-ray microanalysis of these accumulations reveals a high content of calcium and phosphorus, besides magnesium, sulphur and chlorine. Analysis of cell areas devoid of the inclusions show significantly lower calcium- and phosphorus-peaks.
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4.
BACKGROUND: Previously, we demonstrated decreased expression of somatostatin mRNA in aged macaque brain, particularly in the prefrontal cortex. To investigate whether or not this age-dependent decrease in mRNA is related to morphological changes, we analyzed somatostatin cells in the cerebra of aged Japanese macaques and compared them with those in rats and tree shrews, the latter of which are closely related to primates. Methods: Brains of aged macaques, tree shrews, and rats were investigated by immunohistochemistry with special emphasis on somatostatin. Results: We observed degenerating somatostatin-immunoreactive cells in the cortices of aged macaques and tree shrews. Somatostatin-immunoreactive senile plaque-like structures were found in areas 6 and 8 and in the nucleus accumbens of macaques, as well as in the nucleus accumbens and the cortex of aged tree shrews, where amyloid accumulations were observed. CONCLUSIONS: Somatostatin degenerations may be related to amyloid accumulations and may play roles in impairments of cognitive functions during aging.  相似文献   

5.
Abstract: Cytoplasmic inclusion bodies that are accumulations of neurofilaments are the pathological hallmark of many neurodegenerative diseases and have been produced in transgenic mice by overexpression of mouse (NF-L and NF-M; light and medium chains, respectively) and human (NF-M and NF-H; medium and heavy chains, respectively) neurofilament subunits. This report describes a neuronal culture model in which human NF-L was overexpressed to produce cytoplasmic accumulations of neurofilaments within cell bodies concomitant with the collapse of the endogenous neurofilament network. Electron microscopy showed that, within accumulations, neurofilaments retained a filamentous structure. The culture model thus provides a novel system in which the effect on neurofilament accumulations of manipulating protein phosphorylation can be studied. Treatment of cells containing neurofilament accumulations with bisindolylmaleimide, a specific protein kinase C inhibitor, resulted in regeneration of the filamentous network; this effect was not due to a change in the level of transfected NF-L expression. These findings lend support to the suggestion that an impairment in the regulation of protein phosphorylation may lead to the accumulation of neurofilaments seen in neurodegenerative disease.  相似文献   

6.
The present paper gives data on the tissue distribution of carbon particles in Amazon mollies exposed for periods of 24–120 h to a 0.05% suspension. Very little carbon penetrated the body, either by way of the intestine or the gills. The little amount that entered appeared to pass almost exclusively through the posterior intestine. There was no anatomical specialization of the cells in this area equivalent to Peyer's patches in the intestine of mammals. We suggest that the uptake in the posterior intestine is related to its greater surface area and possibly to some enhanced mobility. After intraperitoneal (ip) injection, carbon that entered the body accumulated at three sites: the heart, the mesentery and, especially, in the head kidney. By 120 h large accumulations were seen in the intertubular areas of the kidney; there was no evidence of excretion of carbon particles from these areas.  相似文献   

7.
Transmissible spongiform encephalopathies (TSEs) or prion diseases are infectious neurological disorders of man and animals, characterised by abnormal disease-associated prion protein (PrPd) accumulations in the brain and lymphoreticular system (LRS). Prior to neuroinvasion, TSE agents often accumulate to high levels within the LRS, apparently without affecting immune function. However, our analysis of scrapie-affected sheep shows that PrPd accumulations within the LRS are associated with morphological changes to follicular dendritic cells (FDCs) and tingible body macrophages (TBMs). Here we examined FDCs and TBMs in the mesenteric lymph nodes (MLNs) of scrapie-affected mice by light and electron microscopy. In MLNs from uninfected mice, FDCs could be morphologically categorised into immature, mature and regressing forms. However, in scrapie-affected MLNs this maturation cycle was adversely affected. FDCs characteristically trap and retain immune complexes on their surfaces, which they display to B-lymphocytes. In scrapie-affected MLNs, some FDCs were found where areas of normal and abnormal immune complex retention occurred side by side. The latter co-localised with PrPd plasmalemmal accumulations. Our data suggest this previously unrecognised morphology represents the initial stage of an abnormal FDC maturation cycle. Alterations to the FDCs included PrPd accumulation, abnormal cell membrane ubiquitin and excess immunoglobulin accumulation. Regressing FDCs, in contrast, appeared to lose their membrane-attached PrPd. Together, these data suggest that TSE infection adversely affects the maturation and regression cycle of FDCs, and that PrPd accumulation is causally linked to the abnormal pathology observed. We therefore support the hypothesis that TSEs cause an abnormality in immune function.  相似文献   

8.
Summary It has been suggested (Yorke and Dickson 1984) that myeloid bodies (MBs) in the retinal pigment epithelium (RPE) of the newt, Notophthalmus viridescens, may represent areas of endoplasmic reticulum where lipids, such as 11-cis retinal derived from phagocytized outer segment tips, accumulate prior to esterification. Experiments in which an artificial ester substrate was added during in-vitro incubations have shown that esterase activity is represented in all areas of the newt RPE endoplasmic reticulum, including sites adjacent to all MBs. In related tests in which the localization of enzyme activity was restricted to areas of the cell where there had been accumulations of naturally-occurring (endogenous) esters, the products of ester hydrolysis were restricted to profiles of endoplasmic reticulum associated with lipid droplets, and with the interior of about 20% of those MBs that appeared completely circular in sections. This enzyme activity was not associated with other MB configurations. Results from endogenous-ester hydrolysis were identical to those obtained after staining with ZIO. This ZIO-reactivity was not affected by pre-incubation with agents that blocked or protected sulphydryl groups, and ZIO-reactive sites associated with MBs did not form complexes with digitonin. These observations suggest that MBs are a site of lipid-ester formation, but that they do not represent unique intracellular areas for this activity.  相似文献   

9.
长江下游重点江段水质污染及对鱼类的毒性影响   总被引:22,自引:0,他引:22  
通过对长江下游安庆,南京,镇江和长江口4江段水质及其对鱼类毒性影响的调查发现,长江下游江段主航道的水质符合国家地面II类标准,但近岸的污染带水质受到一定程度的污染,其主要污染物为石油烃类和挥发酚等,这些污染物对鱼类有一定的毒性影响,可引起鱼类的急性中毒,并可诱导鱼类产生微核,同时在上述几个江段内的鱼体内可检出较高的污染物残留,这表明长江下游江段已受到不同程度的污染,这种污染对区域性渔业有影响。  相似文献   

10.
Three cases of eosinophilic granuloma of the lung were histopathologically analyzed on surgical materials (two resections and lung biopsy). The analysis insisted upon the cell components of pulmonary lesions, histiocytic and eosinocytic accumulations involving lobular air spaces, alveolar walls and interlobular areas, and forming bullae by histiocytic enzymic activity and lipid dysmetabolism; the fibrotic evolution of the lesions varied from case to case. The lesional histogenesis is discussed in the light of recent electronmicroscropic, histochemical and immunopathological data, stress being laid upon the local influence on the development of the process.  相似文献   

11.
Mass accumulations of belemnite rostra ('belemnite battlefields') are common in Mesozoic sediments, and accumulations of belemnoids are also known from older rocks. Many Recent teuthid species suffer mortality immediately after spawning, and some authors have suggested that belemnite accumulations record a similar phenomenon. Conversely, it is clear that many belemnite battlefields actually formed in an environment of net sediment loss, with current alignment and winnowing. A proposed model for the production of belemnite battlefields involves five possible pathways: post-spawning mortality, catastrophic mass mortality, predation concentration, stratigraphical condensation, and resedimentation. Although accumulations that have not been reworked are rare, it is possible to recognise the generating agents of belemnite accumulations through their intrinsic features. A genetic classification of belemnite battlefields, based on the identified pathways, is tested through field examples in Britain and Antarctica, as well as through published examples. □ Belemnites, fossil accumulations, palaeoecology, Mesozoic, Antarctica, Yorkshire.  相似文献   

12.
The endoplasmic reticulum (ER) of live metaphase II mouse eggs and prophase I-arrested oocytes was compared using the fluorescent, lipophilic dicarbocyanine dye, DiI. DiI, dissolved in soybean oil, was microinjected into oocytes and eggs; the dye diffused throughout the cytoplasm to label the ER, which was imaged by confocal microscopy. The mature egg had a fine reticular network of ER throughout the cell and numerous dense accumulations of membrane in the cortex. These ER accumulations, 1-2 μm in diameter, were generally absent deeper in the cytoplasm. A similar staining pattern was observed when the eggs were fixed within 1 min of injection, providing evidence that the cortical accumulations of membrane are part of a continuous ER membrane system, since membrane trafficking could not occur in a fixed egg. Cortical ER accumulations were localized to the same region of the egg as the cortical granules and were not observed in the cortical granule-free region adjacent to the meiotic spindle. In contrast, ER accumulations were rarely found in the cortex of the immature, prophase I-arrested oocyte, but larger and less well-defined membrane clusters were found throughout the deeper cytoplasm of the oocyte. The appearance of ER clusters in the egg cortex following oocyte maturation correlates with an increased ability of the mature egg to release calcium at fertilization. Since the ER is a calcium store, structural reorganization of the ER may be necessary to permit the large release of calcium and resulting cortical granule exocytosis at fertilization.  相似文献   

13.
Acid shock of Chlamydomonas results in flagellar excision and induction of flagellar protein RNAs. The magnitude of flagellar RNA accumulations after flagellar excision by mechanical shear depends on the extracel]ular Ca2+ concentration. In this report, we demonstrate that the magnitude and duration of flagellar RNA accumulations are signaled by an acid shock-induced Ca2+ influx. RNA accumulations were greater in cells acid shocked in 500 µM CaCl2 than in 200 µM CaCl2, although the accumulation durations were similar. RNA accumulations of lower magnitude and shorter duration were observed in cells in Ca2+-containing buffer treated with CdCl2. RNA accumulations were of still lower magnitude and shorter duration in cells shocked in buffer without added CaCl2 than in cells shocked in 200 or 500 µM CaCl2 or in the presence of CdCl2. RNA accumulations similar to those in cells shocked in buffer without added CaCl2 were measured in cells following acid shock in buffer containing 200 µM CaCl2 and supplemented with neomycin, ruthenium red, or LaCl3. Acid shock of the adf-1 mutant resulted in RNA accumulations of shorter duration and lower magnitude than those measured in adf-1 cells stimulated by mechanical shear. These results are consistent with an hypothesis that acid shock generates two genetically and pharmacologically distinct signals governing flagellar RNA induction; the first signal is independent of a Ca2+ influx and flagellar excision and results in low magnitude accumulations of short duration, and the second is a consequence of a Ca2+ influx and results in accumulations of high magnitude and long duration.  相似文献   

14.
The characteristics of K, Na contents of the pasture-for-cutting of Aneurolepidiurn chinense grassland of Northeast China were studied. Results showed that: K concentration of every organ of the aboveground part of A. ch inense was highest in early growing season, then decreased gradually as plant continues to grow. The variation of Na concentration was more or less similar to that of K, but there was a sudden increase in August. The concentrations of K, Na in the aboveground part of the community were higher than those in the underground part..The variations of K, Na accumulations of the aboveground part of ,A. chinense in the growing season were of the single-peak type, the peaks of K and Na appeared in July and August respectively. The variations of K, Na accumulations of the aboveground parts of Carex duriuscula and Heleocharis acicularis were similar to those of the biomass, which were of the double-peak type. The accumulations of K and Na in the underground part of community were significantly higher than those in the aboveground part; the accumulations of K, Na in leaf and stem were very close to each other. The K, Na accumulations in the community were accounted for 0.25% and 0.71% of the total reserves of the soil, 2.31% and 0.93% of the soluble plus exchangeable reserves of the soil respectively.  相似文献   

15.
Four types of spontaneous amebocytic accumulations have been reported in Biomphalaria glabrata. Results of crosses involving snails with and without accumulations suggest that the formation of the amebocytic accumulations is controlled by a polygenic system of inherited factors.  相似文献   

16.
Logistic模型预测东北越冬代水稻二化螟发生期   总被引:2,自引:1,他引:1  
2001~2003年在吉林省柳河县绿色大米生产稻区,采用Logistic模型拟合越冬代二化螟Chilosuppressalis(Walker),有效积温和诱捕器诱蛾百分率的关系。结果表明logistic模型有较好的拟合性。由模型拟合结果预测当地越冬代二化螟发蛾始盛期、高峰期和盛末期所需有效积温分别为275.9,358.4和440.8日.度,可以适时指导大田防治。  相似文献   

17.
Summary The fine structure of mitochondrial accumulations in axonal swellings of human sympathetic ganglia is described. A typical swelling contained, in addition to regularly organized mitochondria, bundles of neurofilaments and vesicles as well as large dense-cored vesicles and myelin figures. Synaptic contacts between axonal swellings with mitochondrial accumulations and ganglion cells were not found.A three-dimensional model of the mitochondrial accumulation based on serial sectioning is presented. The possible degenerative and regenerative features of these accumulations are discussed. It is possible that mitochondrial accumulations are functionally active energy producers rather than results of degenerative processes.  相似文献   

18.
Competition effect in DNA damage response   总被引:1,自引:0,他引:1  
We have built an ion-microbeam for studies of the nuclear topography and kinetics of double-strand break repair at the single cell level. Here, we show that a first and a second, delayed single ion exposure at different nuclear sites led to comparable accumulations of phospho-ATM, γ-H2AX and Mdc1 at both earlier (e) and later (l) microirradiated sites. In contrast, accumulations of 53BP1 and the recombination protein Rad51 were strongly reduced at l-sites. This apparent competition effect is accompanied by a reduced amount of 53BP1 in undamaged areas of the irradiated nuclei. We suggest that a critically limited pool size combined with strong binding at irradiated sites leads to the exhaustion of unbound factors freely roaming the nuclear space. The undersupply of these factors at l-sites requires in addition a long-lasting binding at e-sites or a weaker binding at l-sites. The observed effects suggest that DNA damage response at individual nuclear sites depends on the time course of damage load. This may have implications for therapeutic radiation treatments. Christoph Greubel, Volker Hable and Guido A. Drexler contributed equally to this work.  相似文献   

19.
Jones  K. R.  Black  M. J.  Oorschot  D. E. 《Brain Cell Biology》1998,27(1):59-68
Paired helical filaments (PHFs) constitute the majority of filaments in neurofibrillary tangles (NFTs), an Alzheimer's disease (AD) characteristic. PHFs consists of two filaments helically twisted around one another in a regular pattern. The effects of possible PHF-inducing candidates, namely aluminium and glutamate, were observed at the ultrastructural level in this investigation. Rat cerebral explants were exposed to aluminium, citric acid and glutamate singly or combined from 7–12 days in vitro (DIV), while control explants remained in basal medium. On 12 DIV, explants were processed for EM. Three–four EM explants were serially sectioned per condition. Ten 60 nm sections from five systematically sampled areas per explant were collected. One section was randomly chosen per sampled area and all neurons within it observed at 81 200– to record the presence of accumulations of curved filaments (CFs), straight filaments (SFs) or PHFs. Using stereological methods, absolute numbers and the percentage incidence of CFs and SFs were calculated. A significant increase in the frequency of neurons containing CF aggregations in aluminium explants compared to glutamate explants was found. There were no significant differences between conditions for neurons containing SF accumulations. Possible PHFs were observed in one aluminium/glutamate-treated explant. These results suggest that aluminium alone can cause significant formation of accumulations of C- or S-shaped CFs, some of which are double-stranded and twisted around one another regularly. However, structures that were possibly PHF-like were only observed in one aluminium-treated explant, thus making it premature to draw an association between aluminium and the induction of AD-like pathology.  相似文献   

20.
The main objective of this work is to quantify the impact of photodynamic/photothermal treatment by using visible LED and NIR laser irradiation through the skin of subcutaneous fat in vivo followed up by tissue sampling and histology. The optical method may provide reduction of regional or site‐specific accumulations of abdominal or subcutaneous adipose tissue precisely and least‐invasively by inducing cell apoptosis and controlled necrosis of fat tissue. As photodynamic/photothermal adipose tissue sensitizers Brilliant Green (BG) or Indocyanine Green (ICG) dyes were injected subcutaneously in rats. The CW LED device (625 nm) or CW diode laser (808 nm) were used as light sources, respectively. Biopsies of skin together with subcutaneous tissues were taken for histology. The combined action BG‐staining and LED‐irradiation (BG + LED) or ICG‐staining and NIR‐laser irradiation (ICG + NIR) causes pronounced signs of damage of adipose tissue characterized by a strong stretching, thinning, folding and undulating of cell membranes and appearance of necrotic areas. As a posttreatment after 14 days only connective tissue was observed at the site of necrotic areas. The data obtained are important for safe light treatment of site‐specific fat accumulations, including cellulite. This work provides a basis for the development of fat lipolysis technologies and to move them to clinical applications. Schematics of animal experiment.   相似文献   

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