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111.
The Effect of Area HMO Market Share on Cancer Screening   总被引:2,自引:1,他引:2       下载免费PDF全文
Objective. Managed care may have widespread impacts on health care delivery for all patients in the areas where they operate. We examine the relationship between area managed care activity and screening for breast, cervical, and prostate cancer among patients enrolled in more managed care plans and patients who are enrolled in less managed plans.
Data and Methods. Data on cancer screening from the 1996 Medical Expenditure Panel Survey (MEPS) were linked to data on health maintenance organization (HMO) and preferred provider organization (PPO) market share and HMO competition at the metropolitan statistical area (MSA) level. Logistic regression analysis was used to examine the relationship between area managed care prevalence and the use of mammography, clinical breast examination, Pap smear, and prostate cancer screening in the past two years, controlling for important covariates.
Results. Among all patients, increases in area-level HMO market share are associated with increases in the appropriate use of mammography, clinical breast exam, and Pap smear (OR for high relative to low managed care areas are 1.75, p <.01, for mammography, 1.58, p <.05, for clinical breast exam, and 1.71, p <.01, for Pap smear). In analyses of subgroups, the relationship is significant only for individuals who are enrolled in the nonmanaged plans; there is no relationship for individuals in more managed plans. No relationship is observed between area HMO market share and prostate cancer screening in any analysis. Neither the level of competition between area HMOs nor area PPO market share is associated with screening rates.
Conclusions. Area-level managed care activity can influence preventive care treatment patterns.  相似文献   
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PURPOSE: In biopsies of patients with locally advanced breast cancer, we investigated the in vivo changes of the gene expression pattern induced by chemotherapy to find genes that are potentially responsible for the efficacy of the drug. EXPERIMENTAL DESIGN: Early cellular responses to chemotherapy-induced damage, both in vivo and in vitro, were investigated by analyzing chemotherapy-induced changes in gene expression profiles. Core biopsies were taken from nine patients with locally advanced breast cancer, before and at 6 hours after initiation of doxorubicin-based chemotherapy. Both samples were cohybridized on the same microarray containing 18,000 cDNA spots. RESULTS: The analysis revealed marked differences in gene expression profile between treated and untreated samples. The gene which was most frequently found to be differentially expressed was p53 up-regulated modulator of apoptosis (PUMA). This gene was up-regulated in eight of nine patients with an average factor of 1.80 (range, 1.36-2.73). In vitro MCF-7 breast cancer cells exposed to clinically achievable doxorubicin concentrations for 6 hours revealed marked induction of PUMA mRNA, as well. CONCLUSIONS: This is the first report describing PUMA mRNA to be up-regulated as a response to chemotherapy in patients. Because PUMA is a known member of the family of BH3-only proapoptotic proteins, this finding suggests PUMA's potential importance for the response to anticancer drugs.  相似文献   
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The international prognostic scoring system (IPSS) is considered the gold standard for risk assessment in primary myelodysplastic syndromes (MDS). This score includes several prognostic factors except serum lactate dehydrogenase (LDH). We evaluated the prognostic power of LDH as an additional variable in IPSS-based risk assessment. For this purpose, a total of 892 patients with primary MDS registered by the Austrian-German cooperative MDS study group was analyzed retrospectively. Multivariate analysis confirmed the value of established parameters such as medullary blasts, karyotype and peripheral cell counts and showed that elevated LDH was associated with decreased overall survival (P<0.00005) and increased risk of AML development (P<0.00005), independent of the system used to classify MDS (FAB or WHO). Moreover, elevated LDH was found to be a significant predictor of poor survival within each IPSS risk group and within each FAB group except RAEB-T. To exploit these results for refined prognostication, each IPSS risk group was split into two separate categories (A=normal LDH vs B=elevated LDH). Using this LDH-assisted approach, it was possible to identify MDS patients with unfavorable prognosis within the low and intermediate IPSS risk groups. We propose that the IPSS+LDH score should improve clinical decision-making and facilitate proper risk stratification in clinical trials.  相似文献   
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Monatsschrift Kinderheilkunde - Bei kinderkardiologischen Patienten bzw. Kindern mit angeborenen Herzfehlern werden häufig diagnostische oder therapeutische Prozeduren durchgeführt, die...  相似文献   
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Between 1971 and 1985, a total of 325 cases of cervical cancer, Stages IB to IIB, in which operation was performed were evaluated with a view toward prognostic factors and survival rates. In radical abdominal operations, a complete resection of parametrial tissue was the goal. Extensive lymphadenectomy of the pelvis was performed. Operative specimens were processed by giant sections comprising cervix, lateral parametria, and vaginal cuff. Lymph nodes were cut by step-serial sections. Exact measurements of tumor sizes were done along with investigations of parametrium and lymph nodes. Tumors were classified according to a ratio of tumor size to size of cervix. Incidence of lymph node involvement increased with tumor size, reaching a maximum of 68.3% in the group with a ratio from 70% to 80%. Direct spread into the parametrium was rarely found, even in larger tumors occupying the entire cervix. parametrial lymph nodes were most often involved; these were scattered over the entire ligament. Five-year survival rates reached 88.1% in patients with no nodal involvement and 60.9% with nodal involvement. In the latter, the results depended on the number of nodal groups involved and the diameter of metastases. Parametrial involvement alone had no influence on healing rates, but when pelvic nodes were simultaneously involved, the results were less satisfactory. Survival rates based on tumor size differed only between the group with a ratio up to 20% and the large-tumor groups, with rates ranging from 97.5% to 70.9%. There was no statistical difference between Stages IB (31.1% positive nodes) and IIB (44.1% positive nodes) with regard to survival rates (82.2% and 76.9%, respectively).  相似文献   
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