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991.
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The methanol soluble portion of black cumin oil, which is prepared by compression of seeds of Nigella sativa L., showed inhibitory effects on arachidonic acid (AA)-induced platelet aggregation and blood coagulation. By bioactive assay of AA-induced platelet aggregation, the methanol soluble part was purified to isolate a new compound 2-(2-methoxypropyl)-5-methyl-1,4-benzenediol (1) and two known compounds, thymol (2), carvacrol (3), having very strong inhibitory activity. Further, we then examined the isolated compounds (1-3) and eight related compounds by the screening test for AA-induced platelet aggregation. Compounds possessing aromatic hydroxyl and acetoxyl group had more potent activity than aspirin, which is well known as a remedy for thrombosis.  相似文献   
994.
A 45-year-old right-handed woman suffered transient aphasia and persistent amnesia after a right thalamic haemorrhage. This patient appeared to have crossed aphasia, although it disappeared within 8 weeks. It is noteworthy that the patient had a unilateral right thalamic lesion but exhibited both verbal and non-verbal memory impairment. Computed tomography and magnetic resonance imaging revealed cerebral haemorrhage in the right thalamus involving the ventral anterior nucleus, medioventral nucleus, mamillothalamic tract, internal medullary lamina, and mediodorsal nucleus. An amytal test was performed and suggested that the right hemisphere was dominant for language functions and the left hemisphere was dominant for visuospatial functions. Single photon emission CT revealed a low perfusion area only in the right thalamus. These findings suggest that the right hemisphere might be dominant for both verbal and non-verbal memory function in this patient, although visuospatial function was lateralized in the left hemisphere.  相似文献   
995.
The effect of unilateral nephrectomy, orchiectomy or partial hepatectomy on the growth of chemically induced rat bladder tumors was investigated. Male F344 rats were treated with 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) for 5 weeks, and surgical resection of one of these organs was performed 2 weeks after the completion of BBN administration. Histological evaluation of the bladder 24 weeks after the start of the experiment revealed that unilateral nephrectomy and orchiectomy significantly increased the numbers of preneoplastic and neoplastic lesions as compared with the corresponding sham-operated groups. Partial hepatectomy also enhanced tumor growth, although not significantly. Immunohistochemical studies examining the effect of organ resection on normal bladder urothelium showed that BrdU immunostaining of urothelial cells significantly increased 7 days after unilateral nephrectomy or orchiectomy, while BrdU incorporation was minimum after partial hepatectomy or sham operation. C-met expression in the bladder urothelium was evident following unilateral nephrectomy or partial hepatectomy, while increased immunoreactivity of androgen receptor was noted following unilateral orchiectomy. Further study is needed to determine the exact mechanism of the bladder tumor growth-enhancing effect associated with organ restriction. Received: 12 July 2000 / Accepted: 23 February 2001  相似文献   
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PURPOSE: To compare the posterior capsule opacification in Scheimpflug photographic images produced by an electronic anterior eye segment analysis system with the histopathological findings in rabbits and humans. SETTING: Department of Ophthalmology, Wakayama Medical College, Japan. METHODS: Opacified posterior capsules were photographed using the EAS-1000 system (Nidek) and were then extracted during vitreous surgery for proliferative diabetic retinopathy or proliferative vitreoretinopathy in 2 patients. In rabbits, phacoemulsification and aspiration (PEA) with intraocular lens (IOL) implantation was performed. The IOL was implanted in the bag or in the sulcus. After intervals of healing, the posterior capsule was photographed with the EAS-1000 and the animals were then killed. In both clinical and experimental specimens, the posterior capsule was processed for light microscopic histology and immunohistochemistry. RESULTS: Opacified human capsules were well imaged by the EAS-1000. Histology showed that lens epithelial cells proliferated with and without an accumulation of extracellular matrix. Details such as rolling of the capsulotomy edge were seen well. Regenerated lens fibers of Soemmering's ring were seen as a mass within the capsule. In the rabbit model, Scheimpflug images accurately represented the capsules as they appeared histologically. CONCLUSION: The EAS-1000 system provided faithful, relatively high-resolution images that corresponded to the histologic findings in the posterior capsules after PEA-IOL surgery in humans and rabbits.  相似文献   
999.
To elucidate mechanisms of hippocampal serotonin release and possible mechanisms of clinical action of carbamazepine (CBZ), we determined interaction between antagonists of N-type (omega-conotoxin GVIA:GVIA), P-type (omega-agatoxin IVA:IVA) Ca(2+) channels, Na(+) channel (tetrodotoxin: TTX) and CBZ on hippocampal basal, Ca(2+)- and K(+)-evoked serotonin releases, using microdialysis in freely moving rats. Basal release was reduced by TTX, GVIA and IVA (GVIA>IVA). Ca(2+)-evoked release was reduced by GVIA but unaffected by TTX and IVA. K(+)-evoked release was reduced by TTX, GVIA and IVA (GVIA相似文献   
1000.
A new cell growth inhibitor, curvularol, was isolated from the fermentation broth of Curvularia sp. RK97-F166. Curvularol showed no antibacterial activity, and very weak antifungal activity. However, curvularol inhibited the cell cycle progression of normal rat kidney (NRK) cells in G1 phase at 150 ng/ml. Curvularol induced the morphological reversion of srcts-transformed NRK cells at 100 ng/ml, and inhibited protein synthesis same as cycloheximide.  相似文献   
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