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991.
Y. Kajiya M. Nakajo N. Ichinari Y. Kajiya K. Yamazumi T. Otuji T. Tanaka 《Abdominal imaging》1997,22(1):111-113
A foregut cyst is formed as a result of abnormal budding and pinching of the tracheobronchial tree when bronchial buds develop
to form the primitive respiratory tree. Foregut cysts are clinically classified as bronchogenic, esophageal, enterogastric,
or ciliated hepatic. We present a foregut cyst that occurred in the retroperitoneum and was difficult to distinguish from
other retroperitoneal cystic mass lesions. Magnetic resonance imaging was useful in revealing the cyst's continuity to adjacent
organs.
Received: 19 June 1995/Accepted: 23 July 1995 相似文献
992.
993.
Immunohistochemical detection of imidazolone, a novel advanced glycation end product, in kidneys and aortas of diabetic patients. 总被引:11,自引:0,他引:11
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T Niwa T Katsuzaki S Miyazaki T Miyazaki Y Ishizaki F Hayase N Tatemichi Y Takei 《The Journal of clinical investigation》1997,99(6):1272-1280
To investigate the role of the Maillard reaction in the pathogenesis of diabetic complications, we produced several clones of monoclonal antibodies against advanced glycation end products (AGEs) by immunizing mice with AGE-modified keyhole limpet hemocyanin, and found that one clone (AG-1) of the anti-AGE antibodies reacted specifically with imidazolones A and B, novel AGEs. Thus, the imidazolones, which are the reaction products of the guanidino group of arginine with 3-deoxyglucosone (3-DG), a reactive intermediate of the Maillard reaction, were found to be common epitopes of AGE-modified proteins produced in vitro. We determined the erythrocyte levels of imidazolone in diabetic patients using ELISA with the monoclonal anti-imidazolone antibody. The imidazolone levels in the erythrocytes of diabetic patients were found to be significantly increased as compared with those of healthy subjects. Then we studied the localization of imidazolone in the kidneys and aortas obtained from diabetic patients by immunohistochemistry using the antibody. Specific imidazolone immunoreactivity was detected in nodular lesions and expanded mesangial matrix of glomeruli, and renal arteries in an advanced stage of diabetic nephropathy, as well as in atherosclerotic lesions of aortas. This study first demonstrates the localization of imidazolone in the characteristic lesions of diabetic nephropathy and atherosclerosis. These results, taken together with a recent demonstration of increased serum 3-DG levels in diabetes, strongly suggest that imidazolone produced by 3-DG may contribute to the progression of long-term diabetic complications such as nephropathy and atherosclerosis. 相似文献
994.
995.
996.
997.
M. Sh. Verbitskii Ya. N. Gotsulyak 《Bulletin of experimental biology and medicine》1997,123(1):100-104
The effects of antiovarian antiserum and monoclonal antibodies to the oolemma antigens on the ultrastructure of mouse oocytes
and their microenvironment are studied. The antioolemma monoclonal antibodies cause more pronounced degenerative changes in
the oocyte that in its microenvironment. Antiovarian antiserum induces greater changes in the microenvironment than in the
oocyte. Changes induced in the oocyte by the antiserum are secondary relative to changes occurring in the microenvironment,
while changes observed in the oocyte treated with monoclonal antibodies are primary.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 1, pp. 115–119, January, 1997 相似文献
998.
999.
A new method has been developed for the coding of EEG tracings which is an alternative to the classical spectral correlation
analysis. This method has made it possible to compensate to a considerable degree for limitations which are unavoidable with
the Fourier transform, and to obtain additional information regarding the form of the tracing, which reflects the fluctuations
of brain potentials. The new system that has been presented for coding the EEG is, in our view, the most adequate (of the
methods known to us) for identifying the individual features of the EEG, in terms of evaluating both their regional differences
and similarities. The data obtained convince us once again of the real existence of high-frequency low-power components of
the EEG, and their enhancement during instrumental learning in dogs (motor alimentary conditioned reflexes). In addition,
data have been obtained pointing to the intensification in some regions of a slow-wave constituent; this has not been observed
previously in carrying out a Fourier transform.
Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow. Translated from Zhurnal Vysshei
Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 44, No. 2, pp. 244–253, March–April, 1994. 相似文献
1000.
Cytoskeletal requirements in Chlamydia trachomatis infection of host cells. 总被引:8,自引:5,他引:3
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Infection of genital epithelial cells by the closely related sexually transmitted pathogens Chlamydia trachomatis serovars E and L2 results in different clinical disease manifestations. Following entry into target host cells, individual vesicles containing chlamydiae fuse with one another to form one large inclusion. At the cellular level, the only obvious difference between these serovars is the time until inclusion maturation, which is 48 h for the invasive serovar L2 and 72 h for serovar E. To begin to define the intracellular events of these pathogens, the effect of cytoskeletal disruption on early endosome fusion and inclusion development in epithelial (HEC-1B) and fibroblast (McCoy) cells was analyzed by fluorescence microscopy. Disruption of microfilaments with cytochalasin D markedly reduced serovar E, but not serovar L2, infection of both cell lines. Conversely, microfilament as well as microtubule disruption, with colchicine or nocodazole, had no effect on serovar E inclusion development but resulted in the formation of multiple serovar L2 inclusions per cell during early and mid-development. Later in serovar L2 inclusion development (> 36 h postinfection), vesicles containing chlamydiae fused to form one large inclusion in the absence of an intact cytoskeleton. These results imply that (i) C. trachomatis serovar E may utilize a different pathway for uptake and development from serovar L2; (ii) these differences are consistent in both epithelial cells and fibroblasts; and (iii) the cytoskeleton plays a unique role in the infection of host cells by these two genital pathogens. 相似文献