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Manufacturers have steadily been decreasing the amounts of estrogen and progestin in oral contraceptives (OCs) in an effort to enhance safety and tolerability while preserving contraceptive efficacy. A new formulation containing 20 microg ethinyl estradiol (EE) and 100 microg levonorgestrel (LNG)--representing the lowest available contraceptive dose of each hormone--has undergone extensive clinical testing in the United States and Germany. A total of 1590 women in 61 centers received 20 microg EE and 100 microg LNG for 6 cycles. Overall, 4 pregnancies possibly related to treatment failure were reported, reflecting an overall Pearl Index (number of pregnancies per 100 woman-years of treatment) of 0.65 and a failure rate of 0.34%. Cycle control was typical of low-dose OC use. Spotting and breakthrough bleeding occurred most commonly during the earlier cycles in each study. Adverse events were typical of those seen with OC use and led to study discontinuation in 6.6% of the women. Intermenstrual bleeding was the cause for early study withdrawal in 2.6% of women. The study results suggest that the combination of 20 microg EE and 100 microg LNG offers the benefits of low hormone content with good contraceptive efficacy, cycle control, and tolerability. 相似文献
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While genetic factors account for a significant proportion of liability to schizophrenia, a body of evidence attests to a significant environmental contribution. Understanding the mechanisms through which genetic and environmental factors coalesce in influencing schizophrenia is critical for elucidating the pathways underlying psychotic illness and for developing primary prevention strategies. Although obstetric complications (OCs) remain among the most well-documented environmental indicators of risk for schizophrenia, the pathogenic role they play in the etiology of schizophrenia continues to remain poorly understood. A question of major importance is do these factors result from a genetic diathesis to schizophrenia (as in gene-environment covariation), act additively or interactively with predisposing genes for the disorder in influencing disease risk, or independently cause disease onset? In this review, we evaluate 3 classes of OCs commonly related to schizophrenia including hypoxia-associated OCs, maternal infection during pregnancy, and maternal stress during pregnancy. In addition, we discuss several mechanisms by which OCs impact on genetically susceptible brain regions, increasing constitutional vulnerability to neuromaturational events and stressors later in life (ie, adolescence), which may in turn contribute to triggering psychosis. 相似文献
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Merkel PA Herlyn K Martin RW Anderson JJ Mayes MD Bell P Korn JH Simms RW Csuka ME Medsger TA Rothfield NF Ellman MH Collier DH Weinstein A Furst DE Jiménez SA White B Seibold JR Wigley FM;Scleroderma Clinical Trials Consortium 《Arthritis and rheumatism》2002,46(9):2410-2420
OBJECTIVE: To document disease activity and functional status in patients with scleroderma (systemic sclerosis [SSc]) and Raynaud's phenomenon (RP) and to determine the sensitivity to change, reliability, ease of use, and validity of various outcome measures in these patients. METHODS: Patients with SSc and moderate-to-severe RP participating in a multicenter RP treatment trial completed daily diaries documenting the frequency and duration of RP attacks and recorded a daily Raynaud's Condition Score (RCS). Mean scores for the 2-week periods prior to baseline (week 0), end of trial (week 6), and posttrial followup (week 12) were calculated. At weeks 0, 6, and 12, physicians completed 3 global assessment scales and performed clinical assessments of digital ulcers and infarcts; patients completed the Health Assessment Questionnaire (HAQ), the Arthritis Impact Measurement Scales 2 (AIMS2) mood and tension subscales, 5 specific SSc/RP-related visual analog scales (VAS), and 3 other VAS global assessments. We used these measures to document baseline disease activity and to assess their construct validity, sensitivity to change, and reliability in trial data. RESULTS: Two hundred eighty-one patients (248 women, 33 men; mean age 50.4 years [range 18-82 years]) from 14 centers participated. Forty-eight percent had limited cutaneous SSc; 52% had diffuse cutaneous SSc. Fifty-nine patients (21%) had digital ulcers at baseline. Patients had 3.89 +/- 2.33 (mean +/- SD) daily RP attacks (range 0.8-14.6), with a duration of 82.1 +/- 91.6 minutes/attack. RCS for RP activity (possible range 0-10) was 4.30 +/- 1.92. HAQ scores (0-3 scale) indicated substantial disability at baseline (total disability 0.86, pain 1.19), especially among the subscales pertaining to hand function (grip, eating, dressing). AIMS2 mood and tension scores were fairly high, as were many of the VAS scores. Patients with digital ulcers had worse RCS, pain, HAQ disability (overall, grip, eating, and dressing), physician's global assessment, and tension, but no significant difference in the frequency of RP, duration of RP, patient's global assessment, or mood, compared with patients without digital ulcers. VAS scores for digital ulcers as rated by the patients were not consistent with the physician's ratings. Factor analysis of the 18 measures showed strong associations among variables in 4 distinct domains: disease activity, RP measures, digital ulcer measures, and mood/tension. Reliability of the RCS, HAQ pain and disability scales, and AIMS2 mood and tension subscales was high. The RP measures demonstrated good sensitivity to change (effect sizes 0.33-0.76). CONCLUSION: Our findings demonstrate that the significant activity, disability, pain, and psychological impact of RP and digital ulcers in SSc can be measured by a small set of valid and reliable outcome measures. These outcome measures provide information beyond the quantitative metrics of RP attacks. We propose a core set of measures for use in clinical trials of RP in SSc patients that includes the RCS, patient and physician VAS ratings of RP activity, a digital ulcer/infarct measure, measures of disability and pain (HAQ), and measures of psychological function (AIMS2). 相似文献
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CD20-directed serotherapy in patients with multiple myeloma: biologic considerations and therapeutic applications 总被引:13,自引:0,他引:13
Treon SP Pilarski LM Belch AR Kelliher A Preffer FI Shima Y Mitsiades CS Mitsiades NS Szczepek AJ Ellman L Harmon D Grossbard ML Anderson KC 《Journal of immunotherapy (Hagerstown, Md. : 1997)》2002,25(1):72-81
Clonotypic B cells circulating in patients with multiple myeloma (MM) express CD20, and it has been suggested that these cells may be clonogenic. Furthermore, 20% of patients with MM express CD20 on their bone marrow plasma cells (BMPCs). Therefore, the authors began a phase II clinical study to determine the activity of the anti-CD20 monoclonal antibody rituximab in MM patients. Nineteen previously treated MM patients received 375 mg/m2 rituximab per week for 4 weeks. Three months after initiation of treatment, patients were assessed for response and received a second course of therapy if their disease was stable (SD) or they achieved a partial response (PR). Six of 19 (32%) patients had either a PR (n = 1) or SD (n = 5), with a median time to treatment failure of 5.5 months (mean, 10.3 months; range, 3-27+ months). All six patients who had a PR or SD had CD20+ BMPC. Overall, rituximab therapy was well tolerated. Because most patients with MM poorly express CD20 on their BMPCs, the authors evaluated agents for their ability to induce CD20 expression and thereby facilitate rituximab binding on MM cells. These studies show that interferon-gamma (IFN-y) induced CD20 expression on MM BMPCs, MM B cells, and healthy donor BMPCs. In contrast, CD20 expression on chronic lymphocytic leukemia, follicular non-Hodgkin's lymphoma, healthy donor B cells, and progenitor cells was unaffected by IFN-y. Rituximab binding to the BMPCs of MM patients was also increased after culture with pharmacologically attainable levels of IFN-gamma (1-100 U/mL). In conclusion, these studies suggest that MM patients with CD20+ BMPCs may benefit from rituximab therapy. Furthermore, IFN-gamma induces CD20 expression on MM BMPCs and B cells and facilitates rituximab binding to MM BMPCs, providing the rationale for clinical trials to examine its use with CD20-directed serotherapies in MM. 相似文献
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B. Hartley-Asp K. Hansson J. Vibe-Petersen H. H. Hansen J. Polacek M. Ellman P. O. Gunnarsson 《Cancer chemotherapy and pharmacology》1996,38(4):309-316
Tauromustine (TCNU) is an exploratory drug that has demonstrated activity in various solid tumors. We examined chromosome aberrations and plasma levels of the drug in two groups of patients receiving either a single dose of 130?mg/m2 or 40?mg/m2 on 3 consecutive days. Peak plasma concentrations (mean ±SD) were obtained at a similar time after both treatments, i.e., at 38±25, 32±24, 28±14, and 40±26 min after administration of 130?mg/m2 on day 1 and after that of 40?mg/m2 on days 1, 2, and 3, respectively. In addition, the cumulative area under the curve (AUC value) determined after administration of 40?mg/m2×3 was similar to that noted after treatment with a single dose of 130?mg/m2, i.e., 180 and 179?μg min ml-1, respectively. Both treatments induced chromosome aberrations (CAs) in peripheral blood lymphocytes. A dose-dependent increase in the number of CAs was found, with 40?mg/m2 producing 5.5% CAs and 130?mg/m2 yielding 20.9% CAs at 24?h after treatment. In addition, although the drug concentration declined to a level under the detection limit between the daily treatments, drug-induced chromosome damage was cumulative, with the 90-min values increasing from 4.8% on day 1 to 14.3% CAs on day 3. In individual patients, no correlation was found between CAs and kinetic parameters; however, the total mean CA yield was in agreement with the total drug exposure (CAs, 14.3% and 14.6%, AUC 180±62.8 and 179±115?μg min ml-1, respectively). 相似文献
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