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51.
To clarify the role of serotonin in cerebral ischemia, we examined the effects of selective serotonin reuptake inhibitors, citalopram and clomipramine, on ischemic neuronal damage in the gerbil. Pretreatment with citalopram (40 mg/kg i.p.) and clomipramine (20 mg/kg i.p.) protected against neuronal destruction of hippocampal CA1 pyramidal cells following 5 min of forebrain ischemia. Furthermore, microdialysis assays showed that a striking increase in extracellular excitatory amino acid levels during ischemia was significantly inhibited by pretreatment with citalopram and clomipramine. However, citalopram (40 mg/kg i.p.) did not alter the extracellular amino acid concentrations in normal gerbils. Thus, serotonin reuptake inhibitors have a protective effect against ischemic neuronal damage. Furthermore, the present result suggests that the protective effect is mediated through prevention of the accumulation of extracellular excitatory amino acids during and after ischemia. 相似文献
52.
From 1965 to 1968, 7716 Japanese-American men were examined and tested for serum cholesterol. After 22 years, 1380 incident cancer cases were identified. Of the site-specific cancers, only colon cancer cases had a significantly lower mean serum cholesterol value than that of noncases (213.0 mg/dl vs 219.0 mg/dl). When the study subjects were separated into either a low, middle or high group, based on their serum cholesterol values, there was a significant inverse trend for cases of oral/pharyngeal/esophageal cancer combined. The association was present for cases diagnosed within 10 years of examination (p = 0.012), but not for cases diagnosed after 10 years. This suggests that the inverse association is due to the metabolic effects of undiagnosed oral/pharyngeal/esophageal cancer upon serum cholesterol levels. These results are discussed in relation to other studies on serum cholesterol. 相似文献
53.
M Kato 《Nihon Jibiinkoka Gakkai kaiho》1991,94(7):990-997
To examine the difference between response of nasal mucosa to specific antigen and that to non-specific stimulus in the same patient, specific nasal provocation was performed using the house dust antigen disk while nasal respiratory resistance was continuously measured by Rhinograph. On the other hand, non-specific nasal provocation was performed with inhalation of methacholine while nasal respiratory resistance was continuously measured with Astograph. Thereafter the resulting response curves were analyzed. Subjects were 12 males and 9 females, who had nasal obstruction, watery rhinorrhoea and sneeze, and were proved to have allergic rhinitis by house dust. To analyze specific response curve, primary nasal respiratory resistance (Rrs.N), reacting time (Ta) and slope signifying increase of nasal respiratory resistance (delta Rrs.N) were used as parameters. To analyze non-specific response curve, primary nasal respiratory resistance (Rrs.N.cont), minimum dose of methacholine that caused an increase of nasal respiratory resistance (Dmin.N) and slope signifying increase of nasal respiratory resistance (Sd.N) were used as parameters. Ta and Dmin.N reflect sensitivity of nasal mucosa. Their values become smaller, it means sensitivity of nasal mucosa becomes higher. Delta Rrs.N and Sd.N reflect reactivity of nasal mucosa. Their values become larger, it means reactivity of nasal mucosa becomes larger.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
O Shinohara S Kato H Yabe M Yabe C Kubota R Mitsuda M Kimura 《The American journal of pediatric hematology/oncology》1991,13(3):263-268
Growth of the patients with hematological malignancies, aplastic anemia, Fanconi's anemia, and Wiscott-Aldrich syndrome who had been treated with bone marrow transplantation (BMT) was studied. Fourteen out of 21 patients showed suppression of linear growth after BMT. Recovery of the growth velocity after 1-2 years tended to occur if BMT was performed at younger age. Six of eight patients with chronic graft-versus-host-disease (CGVHD) had impaired growth after BMT, whereas eight of 13 (61%) without CGVHD did. Provocative tests for growth hormone (GH) performed 5-72 months after BMT revealed three boys who showed poor response to more than two different stimuli. Two of these three boys had prolonged suppression of growth. Neither the age at BMT, difference in disease, nor presence of posttransplant growth retardation gave significant difference in the response of GH to provocative tests. It was concluded that approximately two-thirds of marrow-grafted children experienced transient decrease in growth velocity after BMT. 相似文献
55.
S Nagano N Fujimoto M Kyo Y Ichikawa M Ishibashi S Takahara H Ihara M Nojima Y Kato A Hirano 《Hinyokika kiyo. Acta urologica Japonica》1992,38(9):1083-1088
A statistic analysis was carried out on the 4,956 inpatients admitted to our Department of Urology from April 1972 to December 1991. The patients included 3,399 males and 1,557 females. A total of 4,105 operations including 255 renal allotransplantations were performed on 3,590 patients. Open surgery for upper urinary tract stones has been replaced by extracorporeal shock-wave lithotripsy (ESWL) in the last three years. 相似文献
56.
Yasuyuki Kato Satoru Miyamoto Hirokazu Minamimura Takumi Ishikawa Kensuke Ohue Yoshihiro Shimizu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(1):46-48
In embryology, a persistent connection of the left superior vena cava to the left atrium rarely coexists with a coronary sinus.
We herein report an unusual case of persistent left superior vena cava terminating in a left atrium with normal coronary sinus,
which was revealed at the time of permanent pacemaker implantation after a second operation for recurrent left atrioventricular
valve regurgitation. Because this anomaly had gone undiagnosed at the first operation, we were unable to diagnose it prior
to the second operation, because the preoperative coronary angiogram clearly demonstrated a coronary sinus that was not dilated.
We would have repaired the anomaly using a patch or other procedure had it been diagnosed before the second operation in order
to prevent cyanosis or brain complications secondary to right-to-left shunting. One should always be on guard for this rare
condition. 相似文献
57.
Coagulation system and platelets play an important role in the stage of lodgement of tumor cells. We examined abilities of human and hamster pancreatic cancer cell lines to aggregate platelets in vitro, and investigated the effect of prostaglandin E1, I2, on artificial liver metastases of pancreatic cancer in Syrian golden hamster. Platelet aggregating activities were found in five out of six human pancreatic cancer cell line and thromboplastin likes activity in five cell lines. Diisopropanolnitrosamine induced hamster pancreatic cancer cells (HPK-1) were able to aggregate platelets both in vitro and in vivo and these activities were inhibited by prostaglandin I2. Hamster was inoculated intraportally with 1 X 10(6) HPK-1 cells. After two weeks autopsy of these hamsters revealed multiple metastatic nodules on liver surface. In this model we administered prostaglandin E1, I2 into the portal vein five minutes before cell inoculation. Number of liver surface nodules were significantly decreased to 33.1 + 7.0, 11.0 + 9.6 in hamster given 100g PGE1 PGI2 before cell inoculation, compared with control group of hamsters (62.0 + 6.6 PH9.3, 66.1 + 13.9 PH7.4). But administration of prostaglandin after cell injection was not effective. In all cases none of extrahepatic metastases were noted. Inhibitory action of PGE1 PGI2 on liver metastasis is suspected to be related to inhibition of platelet aggregation. 相似文献
58.
Yoshio Hayashi Kazuyoshi Ikuta Nobutaka Fujii Kunio Ezawa Shiro Kato 《Archives of virology》1989,105(1-2):129-135
Summary Only one peptide of CD4 (amino acid residues 70–132) among 16 synthetic peptide fragments selectively inhibited HIV-1 replication and HIV-1-induced syncytium formation. Several smaller peptides within this region did not show any activity, except for the peptide (86–132) which showed somewhat lower activity. 相似文献
59.
A new cell line (DMBA-OC-1) from 7,12-dimethylbenz (a) anthracene (DMBA) which induced ovarian carcinoma in rat was established and characterized. DMBA-OC-1 cells showed a paving-stone-like growth pattern at around the 10th to 20th passage, but at the point exceeding the 40th passage the cells showed a spindle form, having strong trends both towards flocculation and piling-up. Furthermore, diastase-resistant PAS-positive and hyaluronidase-digested Alcian blue positive substances were observed in cytoplasms. The cells also showed marked phagocytic activity. These findings suggest that DMBA-OC-1 cells are most likely the site of mesothelial cell origin. 相似文献
60.