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1.
清代岭南词人与岭外有着不断的词学交流,这对岭南词有积极的影响。首先,词学交流促进了清代岭南词人的成长与岭南词的发展。另外,这种交流有助于清岭南词人与岭南词地位的提升。再者,词学交流还对岭南词风的嬗变有重大的影响。  相似文献   

2.
The report is concerned with a study of fine structures of brain capillaries in 9 embryos received during medical abortions from schizophrenic mothers. The authors established some traits in the ultrastructure of endothelial cells in most of the studied cases--an increase of the surface of endothelial cells at the expense of a tortuosity of their plasmatic membranes and a formation of growths, vacuolization of the cytoplasma. There were also some changes in the structure of basal membranes. In 2 cases there were also peculiar pathological changes in the vascular endothelium: granules of an unknown nature in the endothelial cells and a focal lysis of the plasmatic membranes of endothelial cells.  相似文献   

3.
The rate of lipid peroxidation (by content of the lipid peroxide transformation end product--malonic dialdehyde) in homogenates of rat brain was studied as affected by hyperoxia and with a protective effect of urea in experiments in vivo and in vitro. In both cases an increase is observed in the malonic aldehyde yield with the effect of oxygen under higher pressure. Urea in physiological concentrations lowers the yield under the effect of hyperoxia in vitro. In experiments in vivo introduction of urea also evokes a decrease in the rate of peroxidation. It is established that hyperoxia and urea affect mainly the ascorbate-dependent system of peroxidation. The compositon of phospholipids in the rat brain was studied under the effect of hyperoxia and urea. No changes were found in the number of fractions under the effect of 6at oxygen, only quantitative changes are observed. With introduction of urea before hyperoxia there occurs a normalization in the phospholipid composition. The authors suppose the protective effect of urea to be due to its influence on membranes.  相似文献   

4.
Unique spiral structures, located in the wall of the hepatic venous system in the dog, were examined in the central veins and the hepatic venous branches, utilizing microvascular corrosion casting and freeze-fracture technique in scanning electron microscopy and transmission electron microscopy of tissue sections. The whole hepatic venous system was divided into 4 portions: the central, sublobular, collecting and branches of the hepatic veins. The central vein was spindle-shaped with several compressions. Removing the endothelial cells of the central vein, pathways of venous sinusoids were like a labyrinth. In the sublobular veins, spiral structures distinctly appeared as the diameter increased. Beneath the endothelial cells in the constricted portions, smooth muscle bundles were found. The spiral structures gradually became irregular in the collecting veins and discontinuous to form shallow constrictions in cast thicker branches of the intrahepatic veins. A single, fine spindle of the central vein was formed by the arrangement of liver cells. The spiral structures of the sublobular vein were formed by smooth muscle bundles. Irregularity of the spiral structures in the collecting veins was caused by smooth muscle bundles anastomosing with adjacent ones. Disappearance of the spiral structure in cast thicker branches of the intrahepatic veins was due to absence of muscle bundles.  相似文献   

5.
The present study was designed to investigate glucose metabolism in the postmature fetus and newborn. In the fetus, the decreased hepatic glycogen content together with the decrease by the same percentage of total hepatic glycogen radioactivity from directly injected [6-3H]glucose demonstrate that fetal glycogenolysis occurs during prolonged gestation. Moreover, fetal glycogen synthesis as tested by in vivo [6-3H]glucose incorporation experiments is inhibited. In vivo experiments with [14C]lactate are consistent with gluconeogenesis, being inactive in the postmature fetus as well as in the normal-term fetus. During the first hr after delivery, our in vivo data about conversion of [14C]lactate to glucose show that the gluconeogenic pathway is not functioning in spite of very high phosphoenolpyruvate carboxykinase activity in the postmature. By 3 hr postpartum, the phosphoenolpyruvate carboxykinase activity, the blood lactate level, the percentage of conversion, and the rate of gluconeogenesis are very elevated in the postmatures as compared to the term neonates. By 6 hr postpartum, despite maintained phosphoenolpyruvate carboxykinase activity, gluconeogenic rate becomes very weak in postmatures kept fasting. This is the time characterized by a profound hypoglycemia. In contrast, fed postmature neonates exhibit normal blood glucose levels by 6 and 12 hr postpartum as a result of sustained rate of gluconeogenesis.  相似文献   

6.
Tissues obtained at autopsy or biopsy from 81 workers and 2 household persons, were chemically digested. The asbestos fibres recovered were characterized by analytical transmission electron microscopy. Among the 83 causes of death were 33 mesotheliomas, 35 lung cancers, 12 asbestosis and 3 from other cancers. Of the three major commercial asbestos fibre types, amosite was found to be the most prevalent fibre, occurring in approximately 76% of the cases, followed by chrysotile in approximately 60% and crocidolite in approximately 24%. Amosite and chrysotile were observed as the single commercial fibre in approximately 22 and approximately 17% of the cases respectively, whereas crocidolite and tremolite were found as the single fibre type in only approximately 2.5% of the cases. Among the fifteen cases where chrysotile and tremolite occurred together, the amount of chrysotile fibre always exceeded tremolite. However, tremolite was also found in ten additional cases where chrysotile was not detected. Amosite was present in four, amosite plus crocidolite in three, and crocidolite alone in one. Amosite was present in all of the insulation workers' lungs studied and was found in the highest concentration in this exposure category. The highest chrysotile concentration was found among workers in general trades. Although most prevalent in shipyard workers lungs, crocidolite concentration is not statistically different among the exposure groups studied. Although crocidolite was found in twenty cases, amosite accompanied it in eighteen of these. Eleven of the 20 cases were from shipyard workers. Of the 8 mesothelioma cases, 7 also contained amosite. Crocidolite alone only occurred in 1 of the 33 mesothelioma cases analysed. We concluded the following: crocidolite exposure occurred among USA insulators and a large percentage of other workers as well; insulation workers are primarily exposed to amosite; mixed fibre exposures are associated with more mesotheliomas than single fibre exposures; chrysotile only exposure is associated with approximately 12% of the mesothelioma cases studied; and if tremolite exposure is associated with chrysotile exposure, the chrysotile amount exceeds that for the associated tremolite.  相似文献   

7.
8.
The study was made of labyrinthine changes induced by lasix dehydration. Changes indicative of Meniere's disease were identified at comparison of the findings obtained by audiological lasix test, caloric optokinetic reactions. Four types of the nystagmic response in the bithermal lasix-test were determined. These reactions are helpful for more precise staging of the disease.  相似文献   

9.
10.
The patch-matrix organization of the striatal complex, which is fundamental to the structural and functional organization of the basal ganglia, is characterized on the basis of both connections and neurochemistry. In order to determine whether differences in the connections and neurochemistry are reflected in differences in synaptic organization, we examined the synaptology of the dopaminergic nigrostriatal projection in the patch-matrix complex of the rat. Three approaches were used. First, deposits of the anterograde tracer, biotinylated dextran amine, were placed in the substantia nigra. Sections of perfuse-fixed neostriatum were then processed to reveal anterogradely-labelled nigrostriatal axons and calbindin-D28k immunoreactivity, a marker for the patch-matrix complex. Secondly, sections of perfuse-fixed neostriatum were immunolabelled to reveal both tyrosine hydroxylase, a marker for dopaminergic structures and calbindin-D28k. Labelled axons in the patches and the matrix were examined at both the light and the electron microscopic levels. Finally, in order to test for the presence of fixed GABA in sub-type of anterogradely-labelled terminals in the neostriatum, ultrathin sections were immunolabelled by the post-embedding immunogold method. Based on morphological analysis, anterogradely-labelled nigrostriatal axons were divided into two types (Type I and Type II). The density of tyrosine hydroxylase labelling in the neostriatum prevented the classification of immunolabelled nigrostriatal axons. The Type I anterogradely-labelled axons and tyrosine hydroxylase-positive axons were found both in the patches and in the matrix. They both formed symmetrical synapses with spines, dendrites and occasionally somata. The morphology, dimensions, type of synaptic specialization and the distribution of postsynaptic targets of axons labelled by both methods were similar in the patches and the matrix. The Type I anterogradely-labelled axons were immunonegative for GABA. The Type II anterogradely-labelled axons were GABA-immunopositive, were found only in the matrix and were only present in those animals in which retrograde labelling was observed in the globus pallidus, they are thus not part of the dopaminergic nigrostriatal projection. It is concluded that although the patch-directed and matrix-directed dopaminergic projections from the ventral mesencephalon arise from different populations of dopaminergic neurons, their innervation of neurons in the patches and matrix is similar. The anatomical substrate, and therefore probably also the mechanism, for dopaminergic modulation of the flow of cortical information through the striatal complex in essentially the same in the patch and in the matrix sub-divisions of the striatal complex.  相似文献   

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