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21.
Summary.  HIV-1 p17 antigen has been studied for its biological significance in vitro as well as its immunological roles in vivo. By immunological approach of antibody-binding to HIV-1 p17 antigens of several subtypes in combination with computerized analysis of those tertial structures, it became evident that, irrelevant of similarity of linear amino acid sequence of different HIV-1 subtypes, a few amino acid substitutions close to or distant from specified epitope(s) affected their tertial structure resulting in change in ability of its binding to selected antibody. ELISA employing two monoclonal antibodies, A144 and C415, could detect p17 of subtypes A and B, but not of subtypes C, D, and E. Since the epitope site corresponding to A144 has been reported to be important for biological activity of p17 of HIV-1, change in tertial structure around this epitope may explain some difference in biology of HIV-1, such as infectivity of subtypes B and E. Accepted January 9, 1998 Received October 24, 1997  相似文献   
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The immunohistochemical localization of three triplet proteins of neurofilaments in normal Kultschitsky cells and tumourlets of the human lung has been studied using avidin-biotin-peroxidase complex (ABC) method. Kultschitsky cells and tumourlets have been stained with antisera against 68 K, 150 K and 200 K dalton components of the neurofilaments, respectively. Ultrastructural observations of human Kultschitsky cells have revealed the presence of bundles of intermediate filaments as well as microtubules and neurosecretory-type granules. In the tumourlets, similarly sized filaments were found, but were relatively scarce. Since intermediate filaments are thought to be specific to differentiated cells and neurofilament proteins are restricted to the neuronal tissues, we conclude that Kultschitsky cells of the lung are of neuronal nature.  相似文献   
24.
Pathologic study of a rare 11-deoxycorticosterone-producing adrenocortical tumor causing primary aldosteronismlike signs and symptoms, revealed several characteristic features as follows: (1) fairly large size with histologic features corresponding to those of benign zone glomerulosa-type aldosteronoma, (2) lack of spironolactone (S) bodies despite S administration, and (3) heavy mast cell infiltration. In order to explain this rare histology, the localization of mast cells in the adrenal glands and functioning adrenocortical tumors of 67 surgical specimens were investigated. The results of the study supported the view that detection of mast cells helps in the differentiation of mineralocorticoid-producing tumors from cortisol-producing ones, and that the observed mast cell infiltration was due, in part, to its production of 11-deoxycorticosterone.  相似文献   
25.
To study the neuronal mechanism of a conditioned taste-aversion (CTA) learning in the pond snail Lymnaea stagnalis, we examined the synaptic connection between the neuron 1 medial (N1M) cell and the cerebral giant cell (CGC), the former is an interneuron in central pattern generator for the feeding response and the latter is a regulatory neuron to the central pattern generator. Inhibitory postsynaptic potential (IPSP) which was evoked in the N1M cell by activation of the CGC was larger and lasted longer in the conditioned animal than that in the control animal. The electrical properties of the cell body of CGC and the responses of the CGC to the chemosensory inputs were not changed during the CTA learning. These results, together with the previous report indicating the existence of excitatory projection from the N1M cell to the feeding motoneuron, suggest that enhanced IPSP in the N1M cell may underlie the suppression of feeding responses in the Lymnaea CTA learning.  相似文献   
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The ophthalmic artery and its branches,measurements and clinical importance   总被引:5,自引:0,他引:5  
Summary Seventy-one Caucasian orbits (36 right, 35 left) were studied by dissection. The diameter of the ophthalmic a. (2 mm from the origin) was 1.54 ± 0.04 mm (male) and 1.31 ± 0.05 mm (female). In individual cases, there were no significant differences in vessel diameter between the right and left sides but, differences in vessel diameter between males and females were more commonly observed in the arteries which leave the orbit (extraorbital group), the individual vessels having a larger diameter in males. The incidence of the ophthalmic a. passing in the orbit medially under the optic n. was 18.6%. The lacrimal a. was observed to arise from the ophthalmic a. in only 82.5% of the cases examined, 15.9% of the cases showed the origin to be at the anastomotic branch of the middle meningealThis article is dedicated to Pr Dr Hoepke on occasion of his 100th birthday  相似文献   
28.
Extranodal formation of lymphoid follicles was morphologically studied in experimental bronchopneumonia. Control gnotobiotic mice had no peribronchial lymphoid follicles and only lymphatic vessels were traced from the terminal bronchiolar region toward larger bronchi. During the week after intranasal inoculation of mycoplasma pulmonis, lymphoid follicles developed in the terminal portion of the lymphatics by the accumulation of small lymphocytes. A loose network of mesenchymal cells and early infiltration of macrophages, following stromal edema, seemed to play an important role in the early accumulation of lymphocytes. Blastic transformation was seen frequently in the center of the accumulated lymphocytes. Two weeks after inoculation plasma cells emerged conspicuously in the periphery of the lymphoid follicles, and the acute phase of bronchopneumonia began to subside. Typical germinal centers with tingible body macrophages and dendritic reticulum cells developed when the bronchitis persisted in a chronical manner.  相似文献   
29.
The molecular structures of 1,1-diphenylethyl methacrylate (1,1-DPEMA) and triphenylmethyl methacrylate (TrMA) were determined by means of X-ray diffraction. 1,1-DPEMA: monoclinic, space group P21/a,a = 9,666(6), b = 19,94(2), c = 8,132(6) Å, β = 104,49(7)°, and Z = 4; TrMA: monoclinic, space group P21/n, a = 17,349(3), b = 9,487(2), c = 11,254(2) Å, β = 102,30(2)°, and Z = 4. Both structures were solved by the direct method and refined by the block-diagonal least-squares procedure to R = 0,175 and 0,056 for non-zero reflections, respectively. In both molecules, conformations about the C(1)? C(2) and C(1)? O(1) bonds are all synperiplanar and one of the two or three phenyl groups attached to the C(5) atom is in trans to the O(2).  相似文献   
30.
The vascular structures in the lymph node and their relation to fluid exchange have been reported in previous communications and it was considered that the morphological changes of the vascular structures were closely correlated with the functional development of lymph nodes as an antibody forming organ. In order to clarify the localization of the given antigen and newly formed antibody in relation to the morphological structure of lymph nodes, the popliteal lymph nodes of rabbits were studied by immuno-fluorescent techniques.
The antibody was found in the pavement arrangement (solid) of reticulum tissue which was formed by the expel of lymphocytes in the cortical mass and by the morphofunctional alterations of the reticulum cells. The given antigen and newly formed antibody were never detected in the follicles throughout the period of this experiment. ACTA PATH. JAP. 22:427–440, 1972.  相似文献   
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