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81.
Akihiro Nakarna Seiichi Hirota Toshihiko Okazaki Kouichi Nagano Sunao Kawano Masatsugu Hori Yukihiko Kitamura 《Pathology international》1998,48(11):843-849
Interstitial cells of Cajal (ICC) are believed to lnitlate the basic contractile activity of the gastrointestlnal tract. Interstitial cells of Cajal express c-kit receptor tyroslne kinase and are deficient in Ws/Ws mutant rats with a small deletion of the c-kit gene . As Ws/Ws rats show remarkable bile reflux to the stomach, the contraction pressure of the pylorus was compared between Ws/Ws and control +/+ rats. The contraction pressure of the pylorus was measured using a mlcrotransducer, which was Inserted through a pln-hole in the anterlor wall of the stomach under anesthesla. The magnitude of bile reflux was estimated by measurlng the content of bile acids In the stomach. The c-kit messenger RNA-expressing cells were detected by in sltu hybrldlzatlon. Frequency and the maxlmum pressure of the contractlon were comparable between Ws/Ws and +/+ rats, but the duration of the contractlon was significantly shorter In Ws/Ws rats than In +/+ rats. The number of c-kit messenger RNA-expresslng ICC in the pylorus of Ws/Ws rats was 1.7% that of +/+ rats. The bile reflux observed in Ws/Ws rats was attributed to the decrease in the duration of the pyloric contraction, which appeared to result from the deficlency of c-kit messenger RNA-expressing ICC. 相似文献
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Helical coiling structures and band patterns of hydrous metaphase chromosomes were documented three-dimensionally by low vacuum scanning electron microscopy (SEM). Fixed or unfixed isolated Chinese hamster metaphase chromosomes were stained with platinum blue (Pt blue) and observed in the backscattered electron mode for low vacuum SEM without any hypotonic treatment or drying processes. Fibrous structures were shown both in the fixed and unfixed hydrous chromosomes; helical chromatid coils and their subcoils were clarified especially in the fixed chromosomes having contrasting alternative bands of light and darkness, while the translucent perichromosomal matrix and compact fibrous structures were recognized in the unfixed chromosomes. The helical coils were more clearly represented in a loosened chromatid of metaphase chromosomes. Treatment with a tris-HCl buffer solution and Pt blue staining in a hydrous condition successfully produced banding patterns similar to G-bands on metaphase chromosomes. These banded chromosomes observed by low vacuum SEM were also analyzed stereoscopically by field emission SEM after critical point drying. These findings indicate that: 1) native or unfixed chromosomes maintain the compact arrangement of high-order helical structures covered with the peri-chromosomal matrix; 2) helical coiling appearances of chromatids frequently observed in previous papers might be caused by loosening of the final level of the high-order structure of the metaphase chromosome; and 3) banding patterns might be produced by the rearrangement or reorganization of chromatin fibers at the 30 nm fiber level after the extraction of some chromosomal components including the peri- or intra-chromosomal materials during the banding procedure. 相似文献
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Michio Tanaka Shutaro Satake Yutaka Kawahara Masaya Sugiura Kenzo Hirao Kazushi Tanaka Tokuhiro Kawara Akihiro Masuda Toshio Nishikawa Takeshi Kasajima 《Pathology international》1991,41(7):487-498
Radiofrequency catheter ablation of the atrioventricular (AV) node or bundle of His was performed in 12 adult mongrel dogs. The aim was to create chronic incomplete AV block (first- and second-degree AV block) and to examine the histopathology of the ablated lesions. However, the late electrophysiological results (2 4 weeks follow up) were various: normal in 2 dogs, mild PR prolongation (< 50%) in 2 dogs, first-degree AV block (PR prolongation a 50%) in 2 dogs, second degree AV block in 2 dogs, complete AV block in 4 dogs. The maximally ablated area (%) of the atrioventricular conduction system in serial histologic sections from dogs with these conditions was 69%, 75%, 89.5%, 95% and 99.5%, respectively. The number of intact conduction cells at the maximally ablated site varied from 6 to 30 in the four cases of incomplete AV block. The mean ablated volume (%) of either the AV node or penetrating His bundle correlated roughly with the degree of AV block. The ablated lesions were well demarcated and almost replaced by dense fibrous tissue at 4 weeks. Interruption (3 dogs) or thinning (1 dog) of the endocardial elastic lamellae was detected, in association with endocardial thickening (mean 913 μm). Endocardial thrombi were found in 3 dogs (2 fresh, 1 organized). We conclude that radiofrequency catheter ablation does not cause severe complicated lesions. Several possible conditions for creating chronic incomplete AV block are discussed. Acta Pathol Jpn 41: 487–498, 1991. 相似文献
85.
Takahiro Hasebe Kiyoshi Mukai Kazuyuki Ishihara Akihiro Kaneko Yukio Shimosato 《Pathology international》1992,42(8):585-594
Thirteen sebaceous gland carcinomas and 10 sweat gland carcinomas were examined to elucidate any important histological parameters influencing their prognosis, and the relationship between immunohistochemical expressions of c-erbB-2 oncoprotein and survival of the patients was analyzed. Sebaceous gland carcinomas with vacuolated cytoplasm in more than 50% of whole tumor area, with necrosis, and without lymphoid cell infiltration in tumor nests and stroma had a higher incidence of tumor recurrence and tumor-related death than tumors with vacuolated cytoplasm in 50% or less of whole tumor area (p < 0.01), without necrosis, and with lymphoid cell infiltration in tumor nest and stroma (p < 0.05). Sweat gland carcinomas of all cases with fatal outcomes demonstrated tubular differentiation in 20% or less of whole tumor area, lymphatic permeation and desmoplastic reaction. Three sebaceous gland carcinomas and three sweat gland carcinomas were positive for c-erbB-2 oncoprotein. Two of three sebaceous gland carcinomas, and all three sweat gland carcinomas developed tumor recurrence and ended in tumor-related deaths. Sweat gland carcinomas with c erbB 2 expression had significantly shorter survival than those with negative immunostain (p < 0.01). Cytoplasmic appearance, tumor necrosis, and lymphoid cell infiltration in tumor nests and stroma of sebaceous gland carcinoma, and tubular differentiation, lymphatic permeation, and growth patterns of sweat gland carcinoma are considered to closely correlate to the prognosis. Immunohisto-chemically detected c erbB 2 oncoprotein may be an indicator of bad prognosis. Acta Pathol Jpn 42: 585–594, 1992. 相似文献
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Hara Masatoshi Tanaka Shigeru Torisu Kumiko Matsukuma Yuta Tsuchimoto Akihiro Tokumoto Masanori Ooboshi Hiroaki Nakano Toshiaki Tsuruya Kazuhiko Kitazono Takanari 《Clinical and experimental nephrology》2021,25(8):822-834
Clinical and Experimental Nephrology - A growing body of evidence has shown that non-alcoholic fatty liver disease (NAFLD) is associated with chronic kidney disease (CKD). Non-invasive fibrosis... 相似文献