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41.
H Kinoshita T Kameyama T Hasegawa T Nabeshima 《Pharmacology, biochemistry, and behavior》1992,42(1):19-23
We investigated the effects of vinconate, a novel vinca alkaloid, on spatial learning deficits induced by the basal forebrain (BF) lesion in rats. Bilateral BF lesions were produced by injecting ibotenic acid (6 micrograms/0.5 microliter/side). In BF-lesioned rats, impairment of spatial learning in escaping onto the platform during training and decrease in spatial bias during the spatial probe trial in Morris's water maze task were both observed. Vinconate (5 and 10 mg/kg) treatment shortened the increase of escape latency to the platform in BF-lesioned rats and significantly reversed the decrease in spatial bias induced by the BF lesion. Vinconate (10 mg/kg) attenuated the decrease in choline acetyltransferase activity in the frontoparietal cortex caused by the BF lesion. The present study suggests that vinconate has an antiamnesic effect on the BF-lesion-induced amnesia by ameliorating the dysfunction in cholinergic neurons. 相似文献
42.
László Prónai Hiroe Nakazawa Kohji Ichimori Yoshinori Saigusa Tomoichi Ohkubo Kazuko Hiramatsu Shigeru Arimori János Fehér 《Inflammation》1992,16(5):437-450
This study was performed to examine the pattern of Superoxide (O
2
–
·) generation from leukocytes using the O
2
–
· specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O
2
–
· generation by leukocytes. The time course of O
2
–
· generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O
2
–
· for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O
2
–
· generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O
2
–
· much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O
2
–
· generation by leukocytes. 相似文献
43.
Kazuki Tamura Tadayuki Oka Kazutaka Ohsawa Takehiko Koji Yoji Watanabe Shigeru Katamine Hiroshi Sato Hiroyoshi Ayabe 《The Journal of heart and lung transplantation》2003,22(4):452-459
BACKGROUND: Cytomegalovirus (CMV) diseases commonly occur in allograft recipients in the early post-transplant period. However, factors responsible for the high incidence of CMV diseases during this period are not yet fully defined. METHODS: Wistar-Furth (WF; RT-1(u)) rats were inoculated with 10(4) plaque-forming units (PFU) of rat CMV (RCMV) intraperitoneally, and then transplanted with allogeneic lungs from Dark Agouti (DA; RT-1avl) rats or stimulated with 10(7) mitomycin C-treated spleen cells from DA rats by daily sub-cutaneous injections for 2 weeks. No immunosuppressive agent was used. Naive WF rats and WF rats grafted with syngeneic lungs or cells were used as controls. The level of RCMV replication in rats was assessed by infectious virus titers in tissues. RESULTS: The virus titers in salivary glands of allogeneic and syngeneic lung graft recipients were significantly higher than in naive WF rats. The level of RCMV replication in rats stimulated with allogeneic spleen cells was significantly higher than in the syngeneic recipient rats: virus titers in the salivary gland of allogeneic and syngeneic recipients reached 4.61 +/- 0.33 and 4.00 +/- 0.37 log(10) PFU/g tissue, respectively, at 14 days post-infection (p = 0.015). The augmented viral replication in allogeneic recipients was confirmed by an increase in the number of RCMV antigen-positive macrophages present in tissue sections of the salivary gland. CONCLUSIONS: Acute lung allograft rejection and allogeneic spleen cell stimulation enhance CMV replication in the salivary gland of rats. Various responses to allogeneic antigens occurring in the process of acute allograft rejection could be risk factors for post-transplant CMV replication and infection. 相似文献
44.
Shigeru Abe Yuichi Sato Shigeharu Inoue Hiroko Ishibashi Naho Maruyama Toshio Takizawa Haruyuki Oshima Hideyo Yamaguchi 《Nippon Ishinkin Gakkai Zasshi》2003,44(4):285-291
The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis. 相似文献
45.
Katsuyoshi Hori Maroh Suzuki Shigeru Tanda Sachiko Saito Mika Shinozaki Qiu-Hang Zhang 《Cancer science》1991,82(11):1309-1316
To elucidate the significance of angiotensin II (AID-induced hypertension chemotherapy, changes of tissue blood flow both in normal subcutis and in tumors (AH109A, LY80) were measured with the hydrogen gas clearance method. A newly-developed anesthetic machine was used to keep the animals' condition constant. Tissue blood flow in normal subcutis and tumors always fluctuated with time under normotension. The nature and the rate of fluctuation in tumor Wood flow were almost identical in two different types of tumors. However, the fluctuation of blood flow in tumor and that in normal subcutis were almost always inversely related when blood flows in these different tissues were measured simultaneously, i.e., when tissue blood flow in normal subcutis decreased, tumor blood flow increased, and vice versa. The findings supported the idea that the connection mode between the tumor vascular bed and normal vascular bed is a parallel circuit. Vascular resistance in the normal vascular bed under All-induced hypertension seemed to be greater than that under normotension, because the All-increased tumor blood flow always exceeded the maximum tumor blood flow under normotension. Due to the fluctuations of tumor blood flow, no-flow or low-flow areas, resistant to delivery of anti-cancer drugs, moved sporadically within the tumor under the normotensive condition. However, good conditions for drug delivery to tumor tissue were induced by All-induced hypertension. 相似文献
46.
M Tsujihata I Kinoshita M Mori K Mori S Shirabe A Satoh S Nagataki 《Journal of the neurological sciences》1987,81(2-3):197-213
The motor end-plate fine structure was studied in 3 patients with type A botulism and compared with that in 4 patients with Lambert-Eaton myasthenic syndrome (LES). In the botulism cases a biopsy of the biceps brachii muscle was performed at the chronic stage. The skeletal muscle showed a neurogenic change. The nerve terminal area had decreased and the postsynaptic regions had been denuded of their nerve terminals in 16% of the regions (9.8% in control). No highly simplified postsynaptic regions were observed. The findings are consistent with those observed at the motor end-plates in motoneuron diseases. By contrast, in LES no changes were observed in the presynaptic region. In the postsynaptic region, the postsynaptic membrane length and membrane density decreased and hypertrophy of the junctional folds was not observed. 相似文献
47.
48.
Takashi Hamasaki Mikio Mori Yoshihisa Kinoshita Tetsuya Saeki Takashi Sakano 《Pediatric nephrology (Berlin, Germany)》1997,11(5):625-627
We evaluated a 1-year course of a newly developed immunosuppressant, mizoribine (at a dosage of 3 mg/kg body weight per day),
in nine children with steroid-dependent nephrotic syndrome. Steroid treatment could be discontinued in two patients and the
maintenance dosage of steroid could be reduced to less than half of that given before mizoribine therapy in a third. There
were no beneficial effects in the remaining six patients. No adverse effects of mizoribine were observed during the course
of therapy.
Received September 20, 1996; received in revised form and accepted April 24, 1997 相似文献
49.
Leiomyosarcoma originating in Meckel's diverticulum: Report of a case and a review of 59 cases in the English literature 总被引:1,自引:0,他引:1
Nobuyuki Shimizu Shu Kuramoto Toshiki Mimura Kaoru Kobayashi Masanori Kobayashi Shigeru Sakai Michio Kaminishi Takeshi Oohara 《Surgery today》1997,27(6):546-549
A 49-year-old woman was referred to our hospital with complaints of epigastric colicky pain and high fever. Abdominal computed
tomography and ultrasonography showed a solid tumor in the lower abdomen. Laparotomy revealed a neoplastic mass arising in
Meckel's diverticulum; therefore, a segment of the ileum, including the tumor-possessing diverticulum, was resected with a
lymph node dissection. A histologic examination confirmed the lesion to be leiomyosarcoma. In the English literature, 59 cases
of leiomyosarcoma in Meckel's diverticulum were reported from 1941 to 1994. The majority of patients were in their 4th decade
of life, with both sexes equally affected. The most frequent symptoms associated with this disease were abdominal pain with
nausea, vomiting, and melena. The majority were larger than egg-size. Although Meckel's diverticulum is difficult to diagnose
preoperatively, mesenteric arteriography may at times prove useful. The standard management of this particular tumor is wide
segmental resection, including the tumor and diverticulum with lymph node dissection. 相似文献
50.
We have prepared a new material for embolisation: ethylene vinylacetate copolymer dissolved in polyvinyl alcohol. When in contact with blood, polyvinyl alcohol rapidly becomes a soft gel, which is accompanied by wedging of the ethylene vinylacetate copolymer. We analysed the histopathology of intra-arterial microemboli in rats, after intracarotid injection of this material. We confirmed that it was applicable to embolisation for neurosurgical treatment. 相似文献