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31.
Yumiko Motoi Masashi Takanashi Masako Itaya Kazuhiko Ikeda Yoshikuni Mizuno Hideo Mori 《Neuropathology》2004,24(1):60-65
In the present case, a patient in whom limb apraxia and asymmetrical parkinsonism developed suggesting corticobasal degeneration, is reported. Neuropathologic examination revealed numerous tufted astrocytes in the precentral cortex in addition to the characteristic pathologic findings of PSP. Therefore, on the basis of clinicopathologic features, atypical progressive supranuclear palsy was diagnosed. In addition, the brain tissue of the present patient was investigated with an antibody specific for four‐repeat tau (4R‐tau). In the precentral cortex, numerous tau‐positive tufted astrocytes, pretangles, and threads were positive for 4R‐tau. Using a confocal microscopy we demonstrated that tufted astrocytes positive for 4R‐tau were adjacent to astrocytes positive for GFAP. The present findings suggest that accumulation of four‐repeat tau in astrocytes is a degenerative process rather than a reactive process. 相似文献
32.
Jun-ichi Shikata MD Kazuhiko Ohtaki Kenjiro Amino Yoshitsugu Takeda 《Surgery today》1990,20(6):660-664
Two nationwide questionnaire surveys of intestinal obstruction in Japan were undertaken, covering two two-year periods, from
January, 1975 to December, 1976 and from January, 1985 to December, 1986, respectively. The findings of a comparative review
of these two surveys indicated that although the overall mortality of intestinal obstruction had not changed between 1975/76
and 1985/86, being 6.8 per cent and 6.5 per cent, respectively, simple adhesive obstruction had decreased from 3.2 per cent
in 1975/76 to 2.0 per cent in 1985/86. The main cause of adhesion was laparotomy and in cases of both simple adhesive obstruction
and strangulated adhesive obstruction, the rate of adhesion secondary to laparotomy of the upper gastrointestinal tract and
colon and rectum had increased between 1975/76 and 1985/86. Obstructions caused by neoplasms had increased from 8.2 per cent
in 1975/76 to 10.0 per cent in 1985/86, while those caused by adhesions had incresed further still, from 42.5 per cent in
1975/76 to 60.8 per cent in 1985/86. Among the latter group, nonoperatively treated cases had increased, which may be accounted
for by the fact that facilities which adopt non-operative treatment using intestinal decompression as the first choice for
simple adhesive obstruction cases have increased. In both surveys, the mortality of cases receiving nonoperative treatment
was lower than that of operative cases. 相似文献
33.
Masahiro Fujita Kazuhiko Ito Hiroshi Kawamoto Saburo Kashii Mihoko Norioka Sumie Monden Minoru Okuma 《European journal of haematology》1993,50(4):200-205
Abstract: A cell line, BAD05, derived from B lymphocytes of an adenosine deaminase (ADA; EC 3,5,4,4)-deficient patient could not proliferate in a serum-free medium containing 100 μmol/l deoxyadenosine. When BAD05 was cultured with ADA-positive fibroblasts, the proliferation of BAD05 was improved. BAD05 cell density increased when the initially mixed ratio of fibroblasts/BAD05 was 1/10 or higher, but decreased when the ratio was 1/20 or lower. Deoxyadenosine concentrations in the medium and ATP and deoxyATP (dATP) levels in the BAD05 were measured after 4 hours of coculture at initial BAD05 cell densities of 1 × 105and 1 × 106cells/ml. Deoxyadenosine concentrations in the medium decreased as the density of fibroblasts increased. The dATP level decreased as the mixed ratio rose. The ratio of fibroblasts/BAD05 rather than the cell density of fibroblasts had a larger effect on the dATP levels in BAD05. Under our experimental conditions, ADA-negative cells proliferated well when the ratio of ADA-positive cells/ADA-negative cells was over 1/10. 相似文献
34.
Kazuhito Yamamoto Hirotaka Osada Masao Seto Michinori Ogura Hisamitsu Suzuki Kazuhiko R. Utsumi Atsushi Oyama Yutaka Ariyoshi Shigeo Nakamura Souji Kurita Toshitada Takahashi Ryuzo Ueda 《Cancer science》1992,83(5):465-476
A case of non-Hodgkin's lymphoma showed a phenotypic and genotypic cell lineage switch twice during nine years of his clinical history; first, T-cell type, pleomorphic small cell lymphoma developed, followed by B-cell type, diffuse centroblastic/centrocytic lymphoma, and finally T-zone lymphoma without follicles again developed, from which AST-1 cultured cell line was established. Karyotype analysis demonstrated a shared abnormal chromosome, der(1)t(1;?)(p36;?), among the first relapsed B-cell tumor, the second relapsed T-cell tumor and AST-1 cell line. Furthermore, T-cell receptor (TCR) γ gene rearrangement bands of the same size were observed in the first relapsed B-cell tumor and the second relapsed T-cell tumor as well as AST-1 cell line. These results suggested that both relapsed tumors of different cell lineages are derived from a common malignant clone, presumably a committed lymphoid stem cell. A unique translocation, t(2;14)(q37;q11.2), which may involve TCR δ/α gene complex, was observed in the second relapsed tumor and AST-1 cells. To attempt to isolate the breakpoint of this translocation, the configuration of TCR δ/α gene complex was studied. The result showed that two rearrangements of TCR α gene detected with Jα probes were the products of the normal TCR rearrangement process, and were not involved in the translocation at this region. This patient, together with the AST-1 cell line, provided us a unique opportunity to study the development and clonal evolution of malignant lymphoma. 相似文献
35.
Yuichi Ando Kenji Kikuchi Naoya Ichikawa Kazuhiko Meigata Yuji Nomura Kenshi Watanabe Yoshifumi Beck Hisakazu Degawa Shinji Tomikawa Takeshi Nagao Hisanori Chida 《Surgery today》1997,27(4):353-356
We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction. 相似文献
36.
Tomohiko Ai M. Horie Kazuhiko Obayashi Shigetake Sasayama 《Pflügers Archiv : European journal of physiology》1998,436(2):168-174
To examine mechanism(s) underlying the accentuated antagonism by angiotensin II (A-II) on twitch tension, we recorded L-type
Ca2+ currents (I
Ca,L) using conventional patch-clamp techniques in single, guinea-pig, ventricular myocytes. I
Ca,L was recorded by a step-pulse protocol after eliminating K+ conductances (internal Cs+ plus tetraethylammonium chloride and K+-free extracellular solution). A-II (100 nM) did not affect basal I
Ca,L, but inhibited I
Ca,L that had been enhanced (approximately 200% of control) by (ISO, isoproterenol 100 nM). The inhibitory action of A-II was
concentration dependent (concentration eliciting 50% inhibition 88±9 pM, n=41) and the ISO-enhanced component of I
Ca,L was completely blocked by A-II at concentrations above 10 nM. CV-11974 (500 nM), an A-II type-1 receptor (AT1) antagonist, prevented the inhibitory action of A-II. Pre-incubation with pertussis toxin (PTX) abolished the inhibitory
effect of A-II. A-II also inhibited the I
Ca,L enhanced by histamine (500 nM) and forskolin (1 μM), but failed to affect I
Ca,L enhanced by intracellular cyclic adenosine monophosphate (1 mM). The inhibitory action of A-II may therefore involve AT1 receptors/PTX-sensitive, guanine nucleotide-binding (G) proteins (Gi)/adenylate cyclase and partially explains the A-II-dependent
accentuated antagonism of inotropy. 相似文献
37.
Isao Iwamoto Hisamichi Baba Yasunori Koga Noriyuki Uchida Kazuhiko Matsuo Kiyoshi Ishii Toshio Onitsuka Kouichirou Shibata 《Surgery today》1990,20(2):158-162
In order to assess the accuracy of electroencephalography (EEG), in children who have undergone cardiac surgery under simple
deep hypothermia, the relation between IQ or schoolwork achievement and the duration of circulatory arrest was investigated
in 75 such children. Abnormal preoperative EEG's were found in 16 per cent of the children while abnormal postoperative EEG's
were found in 17 per cent. The children were divided into 4 groups, according to pre- and postoperative EEG results. Schoolwork
achievement scores ranged between 3.0 and 3.2, the difference among the groups being insignificant. Moreover, no significant
shift in IQ was found among the groups. Finally, regarding the number of children who were able to go on to a higher level
of education, including high school the college or university, again no significant differences were found among the 4 groups.
In a comparison with the number of such children in neighboring Nagasaki prefecture able to continue on to a higher level
of education, no significant differences were seen either. The findings and statistics of this investigation therefore indicate
that pre- and postoperative EEG's are not always a reliable reference for assessing the prognosis of cerebral activity. 相似文献
38.
39.
Eimoto Hiroyuki; Tsutsumi Masahiro; Nakajima Akira; Yamamoto Kazuhiko; Takashima Yokashima; Maruyama Hiroshi; Konishi Yoichi 《Carcinogenesis》1988,9(12):2325-2327
Expression of glutathione S-transferase placental form (GST-)in human lung carcinoma tissue taken at autopsy or biopsy wasinvestigated immunohistochemically. All of 34 cases of squamouscell carcinomas, including poorly, moderatelyand well-differentiatedexamples were shown to stain positively for GST-. Poorly differentiatedadenocarcinomas were, however, negatively stained (0/5 cases),while moderately and well differentiated adenocarcinomas werefound tostain with GST- at rates of 69% (9/13 cases) and 71%(5/7 cases), respectively. Six cases of small cell carcinomasexamined were all negative. The results indicate that GST- maybe a useful marker fornon-small cell type lung cancer, especiallysquamous cell carcinoma which is in agreement with findingsfor rat lung neoplastic lesions reported previously. 相似文献
40.
Otagiri Masaki Yamamichi Ryuji Marayama Toru Imai Teruko Suenaga Ayaka Imamura Yorishige Kimachi Kazuhiko 《Pharmaceutical research》1989,6(2):156-159
The interactions of acidic and basic drugs with 1-acid glycoprotein (1-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to 1-AGP. The CD data suggested the presence of a single binding site on the 1-AGP molecule. The induced ellipticities of the acidic drug–1-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to 1-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with 1-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs. 相似文献