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An effective vehicle to change behaviors is entertainment education. To demonstrate entertainment education effects, researchers must first indicate that participants have been exposed to their program. Exposure to effective programs has been associated with increases in knowledge about program topics, attitude change, and self-efficacious perceptions. The purpose of this study was to develop and test a new exposure technique that accurately and precisely determines direct exposure levels to Ethiopia's Journey of Life. Overall, the study found very high listenership, storyline recall, liking of the program, and strong desire to change behavior while maintaining low error rates in terms of verbatim recall of storylines and reported listenership to a fictitious program. 相似文献
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Capecitabine: a review 总被引:22,自引:0,他引:22
BACKGROUND: Fluorouracil (FU) is an antimetabolite with activity against numerous types of neoplasms, including those of the breast, esophagus, larynx, and gastrointestinal and genitourinary tracts. Systemic toxicity, including neutropenia, stomatitis, and diarrhea, often occur due to cytotoxic nonselectivity. Capecitabine was developed as a prodrug of FU, with the goal of improving tolerability and intratumor drug concentrations through tumor-specific conversion to the active drug. OBJECTIVES: The purpose of this article is to review the available information on capecitabine with respect to clinical pharmacology, mechanism of action, pharmacokinetic and pharmacodynamic properties, clinical efficacy for breast and colorectal cancer adverse-effect profile, documented drug interactions, dosage and administration, and future directions of ongoing research. METHODS: Relevant English-language literature was identified through searches of PubMed (1966 to August 2004), International Pharmaceutical Abstracts (1977 to August 2004), and the Proceedings of the American Society of Clinical Oncology (January 1995 to August 2004). Search terms included capecitabine, Xeloda, breast cancer, and colorectal cancer. The references of the identified articles were reviewed for additional sources. In addition, product information was obtained from Roche Pharmaceuticals. Studies from the identified literature that addressed this article's objectives were selected for review, with preference given to Phase II/III trials. RESULTS: Capecitabine is an oral prodrug that is converted to its only active metabolite, FU, by thymidine phosphorylase. Higher levels of this enzyme are found in several tumors and the liver, compared with normal healthy tissue. In adults, capecitabine has a bioavailability of approximately 100% with a Cmax of 3.9 mg/L, Tmax of 1.5 to 2 hr, and AUC of 5.96 mg.h/L. The predominant route of elimination is renal, and dosage reduction of 75% is recommended in patients with creatinine clearance (CrCl) of 30 to 50 mL/min. The drug is contraindicated if CrCl is < 30 mL/min. Capecitabine has shown varying degrees of efficacy with acceptable tolerability in numerous cancers including prostate, renal cell, ovarian, and pancreatic, with the largest amount of evidence in metastatic breast and colorectal cancer. Single-agent capecitabine was compared with IV FU/leucovorin (LV) using the bolus Mayo Clinic regimen in 2 Phase III trials as first-line treatment for patients with metastatic colorectal cancer. Overall response rate (RR) favored the capecitabine arm (26% vs 17%, P < 0.001); however, this did not translate into a difference in time to progression (TTP) (4.6 months vs 4.7 months) or overall survival (OS) (12.9 months vs 12.8 months). In Phase II noncomparative trials, combinations of capecitabine with oxaliplatin or irinotecan have produced results similar to regimens combining FU/LV with the same agents in patients with colorectal cancer. In metastatic breast cancer patients who had received prior treatment with an anthracycline-based regimen, a Phase III trial comparing the combination of capecitabine with docetaxel versus docetaxel alone demonstrated superior objective tumor RR (42% vs 30%, P = 0.006), median TTP (6.1 months vs 4.2 months, P < 0.001), and median OS (14.5 months vs 11.5 months, P = 0.013) with the combination treatment. Noncomparative Phase II studies have also supported efficacy in patients with metastatic breast cancer pretreated with both anthracyclines and taxanes, yielding an overall RR of 15% to 29% and median OS of 9.4 to 15.2 months. The most common dose-limiting adverse effects associated with capecitabine monotherapy are hyperbilirubinemia, diarrhea, and hand-foot syndrome. Myelosuppression, fatigue and weakness, abdominal pain, and nausea have also been reported. Compared with bolus FU/LV, capecitabine was associated with more hand-foot syndrome but less stomatitis, alopecia, neutropenia requiring medical management, diarrhea, and nausea. Capecitabine has been reported to increase serum phenytoin levels and the international normalized ratio in patients receiving concomitant phenytoin and warfarin, respectively. The dose of capecitabine approved by the US Food and Drug Administration (FDA) for both metastatic colorectal and breast cancer is 1250 Mg/M2 given orally twice per day, usually separated by 12 hours for the first 2 weeks of every 3-week cycle. CONCLUSIONS: Capecitabine is currently approved by the FDA for use as first-line therapy in patients with metastatic colorectal cancer when single-agent fluoropyrimidine therapy is preferred. The drug is also approved for use as (1) a single agent in metastatic breast cancer patients who are resistant to both anthracycline- and paclitaxel-based regimens or in whom further anthracycline treatment is contra indicated and (2) in combination with docetaxel after failure of prior anthracycline-based chemotherapy. Single-agent and combination regimens have also shown benefits in patients with prostate, pancreatic, renal cell, and ovarian cancers. Improved tolerability and comparable efficacy compared with IV FU/LV in addition to oral administration make capecitabine an attractive option for the treatment of several types of cancers as well as the focus of future trials. 相似文献
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Laverty S Sandy JD Celeste C Vachon P Marier JF Plaas AH 《Arthritis and rheumatism》2005,52(1):181-191
OBJECTIVE: To examine the concentration of glucosamine in the synovial fluid and its pharmacokinetics in serum in a large animal model following dosing with glucosamine HCl at clinically relevant levels. METHODS: Eight adult female horses were studied. After an overnight fast, glucosamine HCl (20 mg/kg of body weight) was administered by either nasogastric (NG) intubation or intravenous (IV) injection. Blood samples were collected before dosing and at 5, 15, 30, 60, 120, 180, 240, 360, 480, and 720 minutes after dosing. Synovial fluid samples were collected from the radiocarpal joints 48 hours before dosing and at 1 and 12 hours after dosing. Glucosamine was assayed by fluorophore-assisted carbohydrate electrophoresis. RESULTS: The maximum concentration of glucosamine in serum reached approximately 300 muM ( approximately 50 microg/ml) following IV dosing and approximately 6 microM (approximately 1 microg/ml) following NG dosing. Synovial fluid concentrations reached 9-15 microM with IV dosing and 0.3-0.7 microM with NG dosing, and remained elevated (range 0.1-0.7 microM) in most animals even at 12 hours after dosing. Following NG dosing, the median serum maximal concentration of 6.1 microM (range 4.38-7.58) was attained between 30 minutes and 4 hours postdose. The mean apparent volume of distribution was 15.4 liters/kg, the mean bioavailability was 5.9%, and the mean elimination half-life was 2.82 hours. CONCLUSION: Clinically relevant dosing of glucosamine HCl in this large monogastric animal model results in serum and synovial fluid concentrations that are at least 500-fold lower than those reported to modify chondrocyte anabolic and catabolic activities in tissue and cell culture experiments. We conclude that the apparent therapeutic benefit of dietary glucosamine on pain and joint space width in humans and animals may be secondary to its effects on nonarticular tissues, such as the intestinal lining, liver, or kidney, since these may be exposed to much high levels of glucosamine following ingestion. 相似文献
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Chapman SB Bonte FJ Wong SB Zientz JN Hynan LS Harris TS Gorman AR Roney CA Lipton AM 《Alzheimer disease and associated disorders》2005,19(4):202-213
The characterization of frontotemporal lobar degeneration (FTLD) is complicated and not widely recognized. Connected language measures (ie, discourse) and functional neuroimaging may advance knowledge specifying early distinctions among frontal dementias. The present study examined the correspondence of discourse measures with (1) clinical diagnosis and (2) single photon emission computed tomography (SPECT) imaging. Nineteen subjects were selected from Alzheimer's Disease Center (ADC) participants if they were diagnosed with early-stage frontotemporal lobar degeneration and also underwent single photon emission computed tomography and discourse evaluation. First, clinical diagnoses given by specialists at an Alzheimer's Disease Center were compared with the discourse-based diagnostic profiles. Secondly, compromised brain regions that were predicted from discourse profiles were compared with SPECT findings. Results revealed a significant correspondence between the ADC diagnosis and the discourse-based diagnoses. Also, the discourse profiles across frontotemporal lobar degeneration subtypes were consistently associated with distinctive patterns of SPECT hypometabolism in the right frontal, left frontal, or left temporal lobes. These findings suggest that discourse methods may be systematized to provide an efficient adjunct measure beyond the traditional word and sentential level measures. Objectifying complex language performance may contribute to early detection and differentiation among frontotemporal lobar degeneration variants because consensus in the literature states that language is a core disturbance of frontotemporal lobar degeneration. 相似文献