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71.
72.
The energy metabolism of the brain was measured in three types of ischemic models in the cat using phosphorus-31 magnetic resonance spectroscopy. The cerebral ischemia was produced as follows. In Group 1, two balloons were inflated in the left subclavian artery and the brachiocephalic trunk. In Group 2, the left middle cerebral artery was occluded through a transorbital approach. A combination of the two was employed in Group 3. Phosphorus-31 magnetic resonance spectra were obtained serially during 2 hours of ischemia. Immediately after occlusion, peaks of phosphocreatine and adenosine triphosphate decreased, whereas the peak of inorganic phosphate increased and split in two. Intracellular pH determined by chemical shift of the inorganic phosphate peak decreased. These changes were more pronounced in Group 3 when compared with the other groups. Histological study showed no infarction in Group 1 and infarcted areas in Groups 2 and 3. The size of the infarcted area in Group 3 was larger than that in Group 2. These results suggest that the model of middle cerebral artery occlusion potentiated with the occlusion of the brachiocephalic trunk and the left subclavian artery by balloon catheters is a reliable stroke model and that phosphorus-31 magnetic resonance spectroscopy is useful to understand the pathophysiological state of cerebral ischemia in vivo. 相似文献
73.
Kazunari Yamaguchi Tsukasa Inaoka Ryutaro Ohtsuka Tomoya Akimichi Tetsuro Hongo Toshio Kawabe Minato Nakazawa Makoto Futatsuka Kiyoshi Takatsuki 《Cancer science》1993,84(7):715-719
Seven hundred and twenty-three serum samples from individuals in 13 Gidra-speaking villages in Western Province, Papua New Guinea were tested for evidence of infection with human T- lymphotropic virus type I (HTLV-I), human immunodeficiency virus type I (HIV-I), hepatitis B virus (HBV) and hepatitis C virus (HCV). No samples were positive for antibodies to HIV-I. Antibodies to HTLV-I were found in 13 samples (1.8%), HBV surface antigens (HBsAg) were found in 86 samples (11.9%), and antibodies to HCV were found in 30 samples (4.1%). Six (46.2%) of 13 HTLV-I positive samples were positive for HCV or HBsAg. The seropositive rate varied in different villages and the incidence of HTLV-I and HCV was higher in coastal and riverine areas than inland. 相似文献
74.
75.
Takahito Adachi Makoto Takeuchi Satomi Uno Motohisa Kato Kiichi Miya Shigetoyo Saji 《Surgery today》1997,27(12):1144-1149
Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor
activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive
activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced
by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA
synthesis, according to measurement by [3H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with
serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted
DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth
factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI4)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide
(MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate
dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI4 with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced
in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment
of liver failure. 相似文献
76.
77.
78.
Four cases of trigeminal schwannoma with different clinical presentations are reported. Two patients had root-type tumors and two ganglion-type tumors. Computed tomography demonstrated the mass in each case, but extension of the tumor into Meckel's cave, displaced but uninvolved seventh and eighth cranial nerves, extension of the tumor into the orbit or into the infratemporal fossa, and other anatomical details were far more clearly shown by magnetic resonance imaging, which provided confirmation of the mass lesions in the base of the brain and within the posterior fossa. 相似文献
79.
Hiroaki Nakamura Marie Yamada Makoto Fukae Hidehiro Ozawa 《Journal of bone and mineral metabolism》1997,15(4):184-192
We investigated the immunohistochemical localization of CD44, hyaluronate receptor, and moesin, of the ezrinradixin-moesin
(ERM) family, in osteoclasts after calcitonin adminstration using confocal laser scanning microscopy and transmission electron
microscopy to clarify the role of CD44 and moesin in their cytoskeletal organization and cell polarity. We also elucidated
the localization of osteopontin (OPN) to confirm its possible role in cell-matrix recognition via CD44. In untreated mice,
intense immunoreactivities for CD44 and moesin were detected on the basolateral plasma membrane of osteoclasts. Rhodamine-phalloidin
reactivity was seen in a bandlike pattern on the region of contact between osteoclasts and bone and was also detected moderately
along their basolateral plasma membrane. At 30 min after calcitonin administration, osteoclasts did not show either clear
zones or ruffled borders. The bandlike reactivity of rhodamine-phalloidin in the contact region was diminished, although labeling
was seen along osteoclasts. CD44 and moesin were colocalized along their plasma membranes, including the region facing the
bone surface. Electron microscopic observation revealed that the microvillus processes in the contacting region with bone
surface, as well as the basolateral plasma membrane, showed immunoreactivities to CD44 and moesin. At 60 min, some osteoclasts
attached to bone and showed a bandlike pattern of rhodamine-phalloidin. On the other hand, OPN was localized under CD44-positive
cytoplasmic processes and the clear zone of osteoclasts. These findings suggest that calcitonin effects on the cell polarity
of osteoclasts and the CD44-moesin-actin filament system in osteoclasts plays an imporant role in cell polarity and cell-matrix
recognition. 相似文献
80.
Toshifumi Murashita Keishu Yasuda Yoshiro Matsui Norihiko Shiiya Shigeyuki Sasaki Makoto Sakuma 《Surgery today》1997,27(4):368-372
A successful replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta in one operation is herein reported. The patient was 66-year-old woman who had DeBakey type I chronic aortic dissection with a pre-disseminated intravascular coagulation (DIC) condition. The image diagnosis revealed a markedly enlarged false lumen with a narrow true lumen in the ascending aorta extending to the diaphragm level while below the diaphragm level, the aortic dilatation was mild. The operation was performed through both a thoracoabdominal incision and a median sternotomy to expose the whole thoracic aorta, and the aorta was replaced from the ascending aorta to the supraceliac abdominal aorta. Selective cerebral perfusion was used for cerebral protection and this was a useful adjunct since no time limitations were thus required during repair of the aortic arch. Although the patient developed several complications postoperatively, she eventually recovered and was discharged from the hospital without any neurological disorders. 相似文献