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101.
PURPOSE: To assess the antitumor efficacy and safety profile of the combination of Fluorouracil (5FU) and vinorelbine given as first-line therapy to patients with advanced breast cancer. PATIENTS AND METHODS: As defined in the seven consecutive steps of a phase II group sequential design, 63 patients received 5FU 750 mg/m2/d for 5 consecutive days as a continuous infusion and vinorelbine 30 mg/ m2 on days 1 and 5 as a short intravenous (I/V) infusion every 3 weeks. RESULTS: Forty-one of 63 patients achieved an objective response, which allowed us to discontinue the study and reject a response rate less than 50% with a statistical power of 90%. The unbiased estimate of the response rate was 61.6%. Response rate did not differ significantly according to the following: (1) type of prior adjuvant therapy (none, n = 23; without anthracycline, n = 6; with anthracyline, n = 34); (2) site of metastatic disease; and (3) number of metastatic sites. The median time to progression was 8.4 months. The median response duration was 12.3 months, and the median duration of complete response (CR), from the first assessment of CR, was 7.3 months. The median overall survival time was 23 months (28.1 months for patients with a CR). The main toxicities (grades 3 and 4) were neutropenia (90% of patients), infection (12.7%), mucositis (37%), and constipation (9.5%). Nevertheless, treatment could be given on an outpatient basis to the majority of patients, and the median relative dose-intensity was 86%. CONCLUSION: This phase II study, which used a group-sequential design, shows that the combination of 5FU and vinorelbine is an active and tolerable regimen for the treatment of first metastatic progression of breast cancer. It provides an alternative regimen for patients who have previously received anthracycline-based adjuvant chemotherapy or in whom anthracyclines cannot be used.  相似文献   
102.
The emergency physician frequently sees patients with cardiac complaints. Too often, ischemic heart disease is overwhelmingly considered to the exclusion of other diagnostic possibilities such as inflammatory cardiac disorders. These disorders can cause considerable discomfort, have long-term implications, or lead to more serious cardiac disorders. Emergency physicians must have a practical understanding of the diagnostic evaluation and therapeutic approach to patients with inflammatory cardiac disorders.  相似文献   
103.
Photoaffinity labeling with [gamma-32P]8N3GTP (8-azidoguanosine triphosphate) was used to identify the guanine binding peptides of the GTT binding site within two types of glutamate dehydrogenase isoproteins (GDH I and GDH II) isolated from bovine brain. 8N3GTP, without photolysis, mimicked the inhibitory properties of GTP on GDH I and GDH II activities. Saturation of photoinsertion of GDH isoproteins revealed an apparent Kd of 8 microM (GDH I) and 24 microM (GDH II) for [gamma-32P]8N3GTP. Ion exchange and reversed-phase high-performance liquid chromatography (HPLC) were used to isolate photolabel-containing peptides generated with trypsin. This identified a portion of the guanine binding domain within the GTP binding site is the region containing the sequence I-S-G-A-S-E-X-D-I-V-H-S-A-L-A-Y-T-M E-R (GDH I) and I-S-G-A-S-E-X-D-I-V-H-S-G-L-A-Y-T-M-E-R (GDH II). The symbol X indicates a position for which no phenylthiohydantoin-amino acid could be assigned. The missing residue, however, can be designated as a photolabeled lysine since the sequences including the lysine residue in question have a complete identity with those of the other GDH species known. Also, trypsin was unable to cleave the photolabeled peptide at this site. Photolabeling of these peptides was prevented by the presence of GTP during photolysis, while other nucleotides could not reduce the amount of photoinsertion as effectively as GTP. These results demonstrate selectivity of the photoprobe for the GTP binding site and suggest that the peptide identified using the photoprobe is located in the GTP binding domain of the brain GDH isoproteins.  相似文献   
104.
105.
PURPOSE: To use fluorophotometry to measure corneal epithelial barrier function after excimer laser photorefractive keratectomy (PRK). SETTING: Seoul National University Hospital, Seoul, Korea. METHODS: Twenty-five eyes of 21 patients (13 women, 8 men) had PRK to correct myopia. Corneal epithelial healing time was measured and corneal epithelial permeability to sodium fluorescein evaluated by fluorophotometry 1, 2, and 3 weeks after surgery. RESULTS: Epithelial permeability showed a statistically significant increase 1 week after surgery and returned to its preoperative level 1 week later. Comparative studies according to epithelial healing day and corrected diopter showed results that were not statistically significant (P > .05). CONCLUSION: These results suggest that PRK delays complete reconstruction of corneal epithelial barrier function. In humans, the corneal epithelium regained its normal barrier function 2 weeks after PRK. Thus, at least during these weeks, care should be taken to minimize further epithelial trauma.  相似文献   
106.
Originally purified as a major lipid component of a strain of the cyanobacterium Lyngbya majuscula isolated in Cura?ao, curacin A is a potent inhibitor of cell growth and mitosis, binding rapidly and tightly at the colchicine site of tubulin. Because its molecular structure differs so greatly from that of colchicine and other colchicine site inhibitors, we prepared a series of curacin A analogs to determine the important structural features of the molecule. These modifications include reduction and E-to-Z transitions of the olefinic bonds in the 14-carbon side chain of the molecule; disruption of and configurational changes in the cyclopropyl moiety; disruption, oxidation, and configurational reversal in the thiazoline moiety; configurational reversal and substituent modifications at C13; and demethylation at C10. Inhibitory effects on tubulin assembly, the binding of colchicine to tubulin, and the growth of MCF-7 human breast carcinoma cells were examined. The most important portions of curacin A required for its interaction with tubulin seem to be the thiazoline ring and the side chain at least through C4, the portion of the side chain including the C9-C10 olefinic bond, and the C10 methyl group. Only two modifications totally eliminated the tubulin-drug interaction. The inactive compounds were a segment containing most of the side chain, including its two substituents, and analogs in which the methyl group at the C13 oxygen atom was replaced by a benzoate residue. Antiproliferative activity comparable with that observed with curacin A was only reproduced in compounds that were potent inhibitors of the binding of colchicine to tubulin. Molecular modeling and quantitative structure-activity relationship studies demonstrated that most active analogs overlapped extensively with curacin A but failed to provide an explanation for the apparent structural analogy between curacin A and colchicine.  相似文献   
107.
108.
There have been considerable efforts to search for naturally occurring substances for the intervention of carcinogenesis. Many components from dietary or medicinal plants have been identified that possess substantial chemopreventive properties. An example is curcumin (Curcuma longa Linn., Zingiberaceae), which has been shown to inhibit tumor promotion in experimental carcinogenesis. Alpinia oxyphylla Miquel, another plant of the ginger family used in oriental herbal medicine, contains diarylheptanoids whose structures are analogous to that of curcumin. In the present study, we have tested A.oxyphylla for its ability to suppress tumor promotion. Thus, topical application of the methanolic extract of dried fruits of A.oxyphylla significantly ameliorated 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin tumor promotion as well as ear edema in female ICR mice. In another study, treatment of HL-60 cells with the methanolic extract of A.oxyphylla significantly reduced the viability of the cells and also inhibited DNA synthesis. Microscopic examination of the treated cells showed characteristic morphology of apoptosis. Furthermore, cells treated with the extract of A.oxyphylla exhibited internucleosomal DNA fragmentation in time- and concentration-dependent manners. TPA-stimulated generation of superoxide anion in differentiated HL-60 cells was also blunted by A.oxyphylla. Taken together, these findings suggest that A.oxyphylla possesses potential chemopreventive and antitumorigenic activities.  相似文献   
109.
Several studies since the commencement of fluoridation in 1955 have demonstrated over 50% reduction in mean dmft for 5-year-old Anglesey children in comparison with local control groups. From 1987 fluoridation became intermittent and in 1991 it was terminated. In the present study, carried out in 1993, the total number of children examined was 725 (88.4% of the entire population of 5-year-old school children), of whom 498 had continually resided in specific water distribution zones. The mean dmft for the entire number examined was 2.01 (SD = 3.27). For those who had experienced fluoridation during approximately 35% of their lives (n = 230) it was 1.81 (SD = 2.86) and for those who had experienced fluoridation for less than 10% of their lives (n = 268) it was 2.28 (SD = 3.48). In 1987/88, the last year of optimal fluoridation, the mean dmft of Anglesey 5-year-old children was 0.80 (SD = 1.43) and for those resident on the non-fluoridated Gwynedd mainland it was 2.26 (SD = 3.17). The study demonstrates the serious consequences for dental health when fluoridation is withdrawn and how difficult it will be to reach dental health targets in North Wales without fluoridation.  相似文献   
110.
BACKGROUND: There have been many studies concerning pathological changes in bronchial mucosa from asthmatics; however, few studies has been carried out to evaluate pathological changes according to the severity of asthma. OBJECTIVE: This study was designed to evaluate the cellular components in bronchoalveolar lavage fluid (BALF) and histological abnormalities in asthmatics according to the severity of asthma. METHODS: Bronchoalveolar lavages, bronchoscopic biopsies and ultrastructural examinations were performed in 13 asthmatics and 11 (BAL) or four (biopsies) non-asthmatic controls. The proportions of epithelial cells and correlations with PC20Meth which reflects bronchial hyperresponsiveness. Light microscopic examination revealed loss of epithelium, inflammatory cell infiltrations and thickening of the basement membrane which also showed significant correlation with PC20Meth. Hypertrophy of airway smooth muscles and hyperplasia of mucous glands were prominent in asthmatics but there was no difference according to the severity of asthma. Ultrastructural examination revealed that basement membrane thickening on light microscopic examination is due to the increased subepithelial collagen deposition with normal thickness of basal lamina. CONCLUSION: These data suggest that loss of epithelial cells, infiltration of inflammatory cells, especially eosinophils, and increased deposition of subepithelial collagen play major roles in determining the severity of asthma and non-specific bronchial hyperresponsiveness.  相似文献   
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