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991.
992.
993.
Dietary bioflavonoids are secondary metabolites of plants that are known to have a variety of bio-effects, including anti-cancer activity. In this study, we examined the effects of flavonoids on the growth of human leukemia cells and found that certain flavonoids induce apoptosis in a variety of human leukemia cells. The apoptosis induced by bioflavonoids was dose-dependent and was accompanied by a disruption of the mitochondrial transmembrane potential and the activation of caspase. Our data suggests that dietary bioflavonoids may be useful chemotherapeutic reagents for leukemia patients.  相似文献   
994.
PURPOSE: Glaucomatous visual field loss and optic disc damage differ by intraocular pressure (IOP) levels. In this study, we compared the optic disc topography in the high-tension group and the low-tension group in normal-tension glaucoma (NTG). METHOD: We selected NTG patients with mean deviation (MD) > or = -10.00 dB and the highest recorded IOP of < 14 mmHg or > or = 17 mmHg without glaucoma treatment. We classified NTG eyes into the following two groups: 1) a low-tension group with the highest recorded IOP of < 14 mmHg, 2) a high-tension group with the highest recorded IOP of > or = 17 mmHg. The optic disc parameters in the low-tension group eyes were compared with those in the high-tension group eyes using a Heidelberg Retina Tomograph. RESULTS: Nineteen eyes of nineteen patients were selected for each group. The cup/disc area ratio in the global sector, and the rim volume in the nasal sector of the low-tension group had deteriorated more than in the high-tension group. CONCLUSIONS: The disc topography is different between the low-tension group and the high-tension group in the nasal sector, suggesting that different pathogenetic mechanisms exist in the optic disc damage in NTG.  相似文献   
995.
Purpose To evaluate the visual acuity outcome and the influence of various factors on visual outcome in patients undergoing surgical removal of type 2 choroidal neovascular neovascularization (CNV) caused by age-related macular degeneration (AMD).Methods We studied the records of 92 patients (92 eyes) who were followed for at least 1 year after surgical excision of CNV associated with AMD.Results The final visual acuity was 0.4 or better in 21%, 0.1 to 0.3 in 66%, and worse than 0.1 in 13% of the patients. Final visual acuity was improved in 62%, stable in 29%, and worse in 9%. Stepwise regression identified CNV size as a significant factor influencing final visual acuity (R = 0.287, P = 0.0045).Conclusions Surgical excision of CNV for AMD is indicated for patients with subfoveal active type 2 CNV with a visual acuity of 0.3 or worse. To achieve better postoperative visual acuity it is important to operate on AMD patients in the early stage of CNV. Jpn J Ophthalmol 2005;49:321–323 © Japanese Ophthalmological Society 2005  相似文献   
996.
The two new anti-dinoflagellates, clonostachysins A and B, were obtained from a marine sponge derived fungus Clonostachys rogersoniana strain HJK9. Their chemical structures were determined by spectroscopic studies as highly N-methylated cyclic peptides of the nine amino acids. The absolute stereochemistry was elucidated by the advanced Marfey's method. Both clonostachysins A and B exhibited a selectively inhibitory effect on a dinoflagellate Prorocentrum micans at 30 microM, but had no effect on other microalgae and bacteria even at 100 microM.  相似文献   
997.
In the present study, we examined the relationships between plasma concentrations of risperidone and clinical responses, extrapyramidal symptoms, plasma levels of cotinine and caffeine, or cytochrome (cyp)2D6 genotypes. In addition, we also investigated the relationships between plasma levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) or homovanillic (HVA) acid and clinical responses to risperidone. One hundred and 36 patients (male/female: 58/78, age 37+/-13 years) who met DSM-IV criteria for schizophrenia, schizoaffective disorder, delusional disorder and brief psychotic disorder, and who were being treated with risperidone alone, were evaluated regarding their clinical improvement and extrapyramidal symptoms using the Positive and Negative Syndrome Scale (PANSS) and Simpson and Angus (SAS), respectively, and plasma levels of cotinine, caffeine, MHPG and HVA were analysed by high-performance liquid chromatography. The cyp2D6*5 and *10 alleles were identified using the polymerase chain reaction. There was a positive correlation between plasma levels of risperidone plus 9-hydroxyrisperidone (active moiety) and SAS scores, but not the PANSS. Pretreatment HVA levels in responders were higher than those in nonresponders. In addition, there was a negative correlation between changes in HVA levels and improvement in PANSS scores. There was no association between plasma levels of risperidone and plasma levels of cotinine or caffeine. Furthermore, there were no differences in the risperidone/9-hydroxyrisperidone ratio, clinical improvements and extrapyramidal symptoms among cyp2D6 genotypes. These results indicate that pretreatment HVA levels and plasma concentrations of active moiety might play a part in predicting the clinical response and occurrence of extrapyramidal symptoms, respectively, when treating patients with risperidone.  相似文献   
998.
Objective To identify the characteristics of patients with myopic choroidal neovascularization (CNV) who had a favorable visual prognosis without treatment.Methods We reviewed the medical records of 52 consecutive patients (57 eyes) with myopic CNV who were followed for at least 5 years after the onset of CNV. Clinical characteristics (patient age, CNV size and location, visual acuity at onset, chorioretinal atrophy development around CNV, and degree of myopia) were compared between patients whose visual acuity 5 years after CNV onset was better than 20/40 and those whose visual acuity was worse than 20/200.Results Among 57 eyes, eight eyes (14.0%; 8 patients) had a final visual acuity better than 20/40. On the other hand, 37 eyes (64.9%; 33 patients) had a final visual acuity worse than 20/200. Statistical analysis revealed that the patients with a good prognosis (final visual acuity better than 20/40) were significantly younger, had significantly smaller CNV, and significantly better initial visual acuity (Mann–Whitney U-test, p<0.05). Juxtafoveal CNV was more frequently observed in patients with a good prognosis than in those with a poor prognosis (Fishers exact probability test, p<0.05). Only one patient (12.5%) in the good prognosis group developed a very limited area of chorioretinal atrophy around the regressed CNV, while 91.9% of the patients in the poor prognosis group developed chorioretinal atrophy. Refractive status and the axial length measurements did not differ between the two groups.Conclusions Some young patients with myopic CNV retain favorable vision over the long term without active treatment. These information might be useful to predict the visual outcome of patients with myopic CNV.The authors have no financial interest in any products/drugs discussed in this article.  相似文献   
999.
In order to reveal one of possible mechanisms for neuronal protective action of extract of Ginkgo biloba leaves (EGBL), the effect of EGBL on kainate- and KCl-induced increases in intracellular Ca(2+) concentration ([Ca(2+)]i) of rat cerebellar neurons was examined using a confocal laser microscope with appropriate fluorescent probes. EGBL at 3 microg/ml started to attenuate kainate-induced increase of [Ca(2+)]i and further increase in EGBL concentration (up to 30 microg/ml) concentration-dependently and significantly inhibited the kainate response. The complete inhibition by EGBL was observed in some neurons when the concentration was 10-30 microg/ml. The kainate-induced increase in [Ca(2+)]i was mainly due to Ca(2+) influx through voltage-dependent Ca(2+) channel opened by membrane depolarization via activation of kainate receptor-channel. However, the increase in [Ca(2+)]i by KCl was not significantly affected by EGBL at concentrations where the kainate response was greatly inhibited. EGBL consisting of flavone glycosides and terpene lactones is known to be an antioxidant. Furthermore, in this study, it is shown that EGBL exerts an inhibitory action on kainate receptor (a subtype of glutamate receptor). Since some of neurodegenerative diseases are due to cell death induced by glutamate excitotoxicity and oxidative stress, EGBL may be very suitable for preventing and/or treating such diseases.  相似文献   
1000.
Inhibitory effects of docosahexaenoic acid (DHA) on the muscle contractions induced by U46619, a thromboxane A2 (TXA2) mimetic, and phenylephrine were compared in guinea-pig aorta. In de-endothelialized guinea-pig aortic ring preparations, DHA at 10 microM strongly inhibited a sustained contraction produced by U46619 (3-100 nM) whereas it did not exhibit an appreciable effect on phenylephrine (3-10 microM)-induced contraction. The present findings indicate that DHA inhibits more selectively TXA2 receptor (TP receptor)-mediated vascular contraction than alpha-adrenoceptor-mediated response. Selective inhibition by DHA of TP receptor-mediated contraction of blood vessels seems underlie in part the mechanisms by which this polyunsaturated fatty acid exerts its circulatory-protective effects.  相似文献   
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