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21.
Seiitsu Ono Takashi Imai Shigeru Munakata Keiichi Takahashi Fumio Kanda Kazuki Hashimoto Takahiko Yamano Natsue Shimizu Koichi Nagao Mitsuo Yamauchi 《Journal of the neurological sciences》1998,160(2):565-147
During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS. 相似文献
22.
Haruhiro INOUE Yukihiko MURAOKA Kimiya TAKESHITA Narihide GOSEKI Mitsuo ENDO 《Digestive endoscopy》1993,5(3):289-292
Abstract: Since April 1991, we have studied 160 patients who had had a successful laparoscopic cholecystectomy. Nine patients who presented with chronic cholecystitis with severe local adhesion and who were also considered to require a longer operative time were selected as suitable candidates for this procedure. They were successfully treated under a zero- to four-mmHg low-pressured pneumoperitoneum procedure combined with total abdominal wall lifting using a disposable, flexible vinyl tube retractor. This method enabled exactly the same clear laparoscopic vision as is possible in the routinely-used high-pressure pneumoperitoneum even in the marginal portions of the abdominal cavity. Moreover, it facilitated early reinsufflation after the cauterization-produced smoke was exhausted, which minimized the operative time and reduced the surgeon's anxiety concerning the maintenance of a sufficiently airtight condition. We believe that this low-pressure pneumopeqitoneum procedure also benefits the poor-risk patient who has restricted cardiopulmonary function, especially during advanced laparoscopic surgery which requires a longer operative and anesthetic time. 相似文献
23.
Seiji Kinugasa Shuichi Tachibana Manpei Kawakami Tatsuhiko Orino Ryuichi Yamamoto Shinjiro Sasaki 《Surgery today》1998,28(3):335-338
(Received for publication on Nov. 14, 1996; accepted on May 12, 1997) 相似文献
24.
Although the esophagus is the most frequent site ofCandida infections in the gastrointestinal tract, and many clinical studies about it have been reported, little attention has been
directed toward experimental candidiasis of the esophagus, especially with regard to its ultrastructure. Using transmission
electron microscopy, this study was performed to clarify the ultrastructure of experimental lesions, obtained from five New
Zealand white male rabbits which were given a suspension ofCandida albicans cells (107/ml) for 13 days. The results showed that the lesions consisted of exfoliating, squamous epithelial cells with mycelial elements
ofCandida albicans cells penetrating through them, and that a widened intercellular space between individual cells in the area of candidial
invasion seems to be a characteristic finding of candidial infection.
A part of this study was presented at the 25th Annual Meeting of the Clinical Electron Microscopy Society of Japan, Matsumoto,
September 28–30, 1993. 相似文献
25.
Possible involvement of arachidonic acid metabolism in phenobarbital promotion of hepatocarcinogenesis 总被引:8,自引:4,他引:4
Denda Ayumi; Ura Hitoshi; Tsujiuchi Toshifumi; Masahiro Tsutsumi; Eimoto Hiroyuki; Takashima Yoshiharu; Kitazawa Shunji; Kinugasa Tetsuo; Konishi Yoich 《Carcinogenesis》1989,10(10):1929-1935
The effects of inhibitors of arachidonic acid metabolism andantioxidants on the rat liver tumor promotion activity of phenobarbital(PB) were assessed using the enzyme-altered focus as the end-pointlesion. Fischer 344 male rats were initiated with N-nitrosodiethylamine(200 mg/kg) and then divided into five groups placed on basaldiet, diet containing 0.05% PB, diet containing 0.05% PB plus0.75%, 1% or 1.5% levels of various inhibitors of arachidonicacid metabolism or antioxidants, or diet containing 1% or 1.5%inhibitors or antioxidants alone for 10 weeks, and then killed.-Bromo phenacyl bromide, an inhibitor of phospholipase A2 significantly inhibited the promotion activity of PB at dose levelsof 0.75% and 1.5%, reaching plateau at 0.75%. Both quercetin,an inhibitor of lipoxygenase, and morin, a dual inhibitor oflipoxygenase-cyclooxygenase, significantly reduced the promotionactivity of PB at the 1.5% but not 0.75% dose levels. Moreover,acetylsalicylic acid, an inhibitor of cyclooxygenase dose-dependentlyinhibited the promotion activity of PB. Among the antioxidantsinvestigated, vitamin E did not affect, but n-propyl gallateand ethoxyquin exerted a dose-dependent inhibition of PB promotion.These results are strongly suggestive of an involvement of phospholipaseA2 lipoxygenase and cyclooxygenase arachidonic acid metabolicpathways in the mechanisms underlying PB enhancement of hepatocarcinogenesis. 相似文献
26.
Suzuki Hisamitsu; Ota Kazuo; Ohno Ryuzo; Masaoka Toru; Shibata Hirotoshi; Kimura Ikuro; Amaki Ichita; Miura Yasusada; Uzuka Yoshiro; Kawato Masafumi; Shirakawa Shigeru; Hirota Yutaka; Maekawa Tadashi; lmai Kuniyuki; Takaku Fumimaro; Shimoyama Masanori; Kitahara Takeshi; Oguro Masao; Kozuru Mitsuo; Kawagoe Hiroya; Nakamura Toru; Yamada Kazumasa 《Japanese journal of clinical oncology》1989,19(4):338-347
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 19711975 to 62.3%during 19811985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 19711975and 69.7% during 19811985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 3740 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe. 相似文献
27.
Tatsuya Ishiguro Yoshikatsu Ozaki M. Mitsuo Yokoyama C. Howard Tseng William Chao 《Immunobiology》1980,157(1):24-29
Peripheral blood samples from 52 women including 16 with herpes genitalis and 36 healthy persons were studied to enumerate subpopulations of lymphocytes. T lymphocyte counts were done by SRBC rosette tests and B lymphocytes by immunobead rosette tests using antibody-coated polyacrylamide beads. It was found that the mean percentage of «active T lymphocytes was significantly less in the patients with herpes genitalis than in the controls (herpes genitalis; 13.9 ± 6.8%, controls; 25.0 ± 8.3%, p < 0.001). No difference was noted in the percentage of «total» T lymphocytes, «total» B lymphocytes and subsets of B lymphocytes (IgG-, IgA- and IgM-bearing lymphocytes) between the patients and controls. The present findings suggest that cell-mediated immune function associated with «active» T lymphocytes is suppressed in patients with herpes genitalis. 相似文献
28.
Mitsuo Sawamoto Toshio Masuda Toshinobu Higashimura 《Macromolecular chemistry and physics.》1976,177(10):2995-3007
The bimodal molecular weight distribution (MWD) of the polymers and the polymerization rate in the cationic polymerization of styrene by CF3SO3H were studied under a variety of conditions. Both the decrease of the dielectric constant of the reaction mixture and the addition of a common-ion salt (Bu4N+SO3CF) reduced the polymerization rate and the formation of the higher molecular weight portion of the polymers (the high polymer). It appears that of the two propagating species the one which forms the high polymer is more ionically dissociated and more reactive in propagation. Salt effects indicate that in nitrobenzene the propagating species is a solvent-separated ion pair and/or a free ion. The effects of monomer concentration on the bimodal MWD have shown that there are different chain-breaking reactions for the two propagating species. The possibility that the monomer is complexed with one of the growing species is also discussed. 相似文献
29.
Kazuo Takayama Kanichi Yagawa Akiko Takahashi Hironori Nishio Morio Sudo Nobuyuki Sasaki Toru Yoshida Masanobu Satoh Hisaaki Abiko Akio Nunokawa Mitsuo Okazaki 《Pathology international》1969,19(4):547-562
A typical case of the D uchenne type of progressive muscular dystrophy with autopsy findings was presented. Changes in the myocardial and smooth muscle of many organs were found, and the skeletal muscles also revealed florid changes.
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation. 相似文献
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation. 相似文献
30.
Akitaka Nonomura Yuji Mizukami Toru Hasegawa Mitsuo Ohkawa Masumi Kadoya 《Pathology international》1995,45(2):160-164
A case of a rare renal tumor showing characteristic histo-logic features is presented. The patient was a 54 year old female, whose renal tumor was incidentally detected on abdominal ultrasound (US) examination. Ultrasound, computed tomography and angiography findings were consistent with a diagnosis of renal cell carcinoma of the hypovascular type. Left nephrectomy was performed. The tumor, which measured 2.6 times2.6 times 2.5 cm, was located in the left renal cortex, and had a uniformly whitish-yellow cut surface and well-defined margin. Histologically, the tumor was characterlzed by its monomorphous growth pattern and was composed of uniformly small cells arranged in a tubular or rosette-like pattern. The tumor cells had scant cytoplasm and the nuclei were small, round and regular. These histo-logic features resembled the epithelial elements of a metanephric hamartoma in the nephroblastomatosis complex in infants. However, there was no mitosis and cellular atypia was minimal, suggesting benignity. According to these his-tologic features, the diagnosis of metanephric adenoma was made. Its clinicopathologic features are discussed. 相似文献