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101.
The preventive effects of green tea, tea pigments, and mixed tea (a composite of whole water extract of green tea, tea polyphenols, and tea pigments) on 7,12-dimethyl-benz[a]anthracene (DMBA)-induced oral carcinogenesis in golden Syrian hamsters were studied. The right buccal pouches of animals were topically treated with 0.5% DMBA three times per week for 15 weeks. Animals were killed separately after 6, 10, and 15 weeks of DMBA treatment. Oral tumors were counted and measured, and mean tumor burden was calculated. The incidence of preneoplastic lesions and micronucleated cells, the number and volume of silver-stained nucleolar organizer regions (AgNOR), the labeling index of proliferating cell nuclear antigen, and the level of epidermal growth factor receptor expression were studied. The results showed that oral administration of 1.5% green tea, 0.1% tea pigments, and 0.5% mixed tea as the sole source of drinking water for two weeks before initiation of the DMBA treatment and until the end of the experiment significantly reduced the mean tumor burden and the incidence of dysplasia and oral carcinoma (p < 0.01). The frequency of micronucleated cells, the number of AgNOR, the total volume of AgNORs, the labeling index of proliferating cell nuclear antigen, and the level of epidermal growth factor receptor expression in the oral mucosal cells were also significantly reduced (p < 0.01). These results clearly indicated that tea preparations could effectively inhibit DMBA-induced oral carcinogenesis in hamsters. Protection from DNA damage and suppression of cell proliferation could be important mechanisms of the anticarcinogenic effects of the tea preparations.  相似文献   
102.
AIMS: To evaluate the effect of trans scleral cyclophotocoagulation (TSCPC) on intraocular pressure (IOP) in the eyes retaining intravitreal silicone oil with medically uncontrolled secondary glaucoma following intravitreal silicone oil injection. METHODS: Medical records of 11 eyes of 11 patients who underwent TSCPC for medically uncontrolled glaucoma without pupillary block following intravitreal silicone oil injection for complicated retinal detachment were reviewed retrospectively. In all cases, intravitreal silicone oil was not removed for fear of retinal redetachment. Diode laser contact TSCPC was performed at a power of 1.5-2.5 W, for a duration of 2 seconds, and with 20-27 applications. IOP, number of glaucoma medications, and success rate were evaluated. RESULTS: After a mean follow up period of 52.5 (SD 8.2) (range 42-68) weeks, the mean pretreatment level of IOP, 43.0 (14.4) (26-67) mmHg, had fallen to 14.5 (4.3) (7-20) mm Hg (p=0.003). The number of glaucoma medications was reduced from 2.6 (0.8) to 0.6 (1.0) (p= 0.005). Qualified success was achieved in nine eyes (81.8%) and complete success in six (54.5%). After TSCPC, patients' retinal status had not changed. CONCLUSION: Patients with medically uncontrolled glaucoma secondary to intravitreal silicone oil injection can be treated with TSCPC in spite of the retained intravitreal silicone oil.  相似文献   
103.
PURPOSE: To present clinical and histologic findings of intraocular infection with Mycobacterium bovis-bacille Calmette-Guérin after intravesicular bacille Calmette-Guérin injections for treatment of bladder carcinoma. METHODS: A 77-year-old man was initially seen with visual acuity of 20/200, focal retinitis, vasculitis, and progressive vitreous opacity in the right eye and visual acuity of light perception, intraocular inflammation, and a dense cataract in the left eye 14 months after intravesicular injection of live bacille Calmette-Guérin organisms. RESULTS: Vitreous cultures in the right eye demonstrated growth of bacille Calmette-Guérin organisms. Bilateral loss of light perception occurred despite systemic antimy-cobacterial therapy. Histopathologic examination demonstrated nongranulomatous inflammation and acid-fast bacilli in both eyes. CONCLUSION: Delayed endogenous endophthalmitis may develop after intravesicular bacille Calmette-Guérin injection that may not respond to systemic agents. Intravitreal therapy may be indicated.  相似文献   
104.
When liriodendrin or syringin was incubated for 24 h with human intestinal bacteria, two metabolites, (+)-syringaresinol-beta-D-glucopyranoside and (+)-syringaresinol, from liriodendrin and one metabolite, synapyl alcohol, from syringin were produced. The metabolic time course of liriodendrin was as follows: at early time, liriodendrin was converted to (+)-syringaresinol-beta-D-glucopyranoside, and then (+)-syringaresinol. The in vitro cytotoxicities of these metabolites, (+)-syringaresinol and synapyl alcohol, were superior to those of liriodendrin and syringin.  相似文献   
105.
In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells.  相似文献   
106.
Cytotoxicities of four urushiols, congeners isolated from the sap of Korean lacquer tree (Rhus vernicifera Stokes), to 29 human cancer cell lines originated from 9 organs were evaluated. Their values of 50% growth inhibition were below 4 microg/ml, and showed cell line specific cytotoxicity. The present result is the first report on the cytotoxicity of urushiols suggesting that they would have an anticancer activity to human cancer cells.  相似文献   
107.
Socialization games, designed to reinforce prosocial behavior between moderately and severely mentally retarded aggressive institutionalized women, were presented to two groups on 12 occasions over 8 weeks, randomly interspersed with 12 sessions of arts and crafts or filmstrip stories. Half of the sessions were presented in the morning and half in the afternoon. Video-taped observations of interpersonal behavior for 10 minutes after each session were analyzed in terms of friendly, unfriendly, and inactive behavior, and the distance of each subject from each other subject was measured. The rate of friendly behavior was significantly greater after the games and was higher in morning than afternoon sessions. The games also significantly decreased interpersonal distance. Both unfriendly behavior and inactivity were higher after the "placebo" sessions. The relevance of these results to institutional programming was discussed.  相似文献   
108.
J G Im  W R Webb  M C Han  J H Park 《Radiology》1991,178(3):727-731
To elucidate the nature of the apical opacity that is commonly seen in patients with tuberculosis--usually referred to as an "apical cap" or "apical pleural thickening"--18 patients with upper lobe tuberculosis were studied with high-resolution computed tomography (HRCT). All had a homogeneous apical opacity at least 1 cm thick on chest radiographs. Fifteen of the 18 had a history of pulmonary tuberculosis of more than 5 years duration, and nine showed evidence of ipsilateral pleurisy. HRCT scans at the apex of the thorax in all nine patients scanned at this level showed that extrapleural fat with interspersed vessels accounted for most of the plain radiographic opacity. Scans obtained at a level slightly above visible aerated lung showed extrapleural fat 3-25 mm thick peripherally and atelectatic lung centrally. At more caudal levels, at which both aerated lung and "thickened pleura" were visible on plain radiographs, HRCT showed extrapleural fat (3-20 mm thick), thickened pleura (1-3 mm thick), and atelectatic lung peripherally and areas of emphysematous bullae, bronchiectasis, and atelectatic lung centrally.  相似文献   
109.
The extracts of sixty Korean plants were evaluated for their biological activities such as antitumor activities against Sarcoma 180, Leukemia SN-36 and Ehrlich ascites carcinoma, antimicrobial activities and behavioral observation in mice. The results are tabulated.  相似文献   
110.
The inhibitory effect of the thoracic duct lymph of a patient with lung cancer on the "one-way" mixed lymphocyte reaction without cytoxicity is unequivocally demonstrated. The effect seems to be dose related. A moderate inhibition of mixed lymphocyte reaction is still observed, even if the responding cells are preincubated in the thoracic duct lymph for 1 hr only prior to the addition of stimulating cells. The inhibitory effect of thoracic duct lymph on the mixed lymphocyte reaction is no longer evident when the material is added 1-4 days after the beginning of culture. These observations suggest that the mechanism of the inhibitory effect of thoracic duct lymph may be a simple attachment of inhibitory factors to the receptor sites on the responding lymphocytes, causing interference in cell to cell interaction. The inhibitory effect of thoracic duct lymph collected 1 week after the thoracic duct drainage on mixed lymphocyte reaction is significantly lower than that of thoracic duct lymph collected at the beginning of the procedure. This indicates that the blocking effect of thoracic duct lymph can be easily removed by this technique; which is technically feasible in man. The interrelationship of the tumor-specific blocking factor, thoracic duct drainage, and tumor growth pattern are discussed with respect to the potential usefulness of this procedure as adjuvant immunotherapy in the management of patients with neoplastic diseases.  相似文献   
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