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PURPOSE: Adjuvant chemotherapy, especially with anthracyclines, is known to cause acute and chronic cardiotoxicity in breast cancer patients. We studied the cardiac effects of chemotherapy in a population-based sample of breast cancer patients aged > or = 65 years with long-term follow-up. PATIENTS AND METHODS: In the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we analyzed treatments and outcomes among women > or = 65 years of age who were diagnosed with stage I to III breast cancer from January 1, 1992 to December 31, 1999. Propensity scores were used to control for baseline heart disease (HD) and other known predictors of chemotherapy, and Cox proportional hazards models were used to estimate the risk of cardiomyopathy (CM), congestive heart failure (CHF), and HD after chemotherapy. RESULTS: Of 31,748 women with stage I to III breast cancer, 5,575 (18%) received chemotherapy. Chemotherapy was associated with younger age, fewer comorbidities, hormone receptor negativity, multiple primary tumors, and advanced disease. Patients who received chemotherapy were less likely than other patients to have pre-existing HD (45% v 55%, respectively; P < .001). The hazard ratios for CM, CHF, and HD for patients treated with doxorubicin (DOX) compared with patients who received no chemotherapy were 2.48 (95% CI, 2.10 to 2.93), 1.38 (95% CI, 1.25 to 1.52), and 1.35 (95% CI, 1.26 to 1.44), respectively. The relative risk of cardiotoxicity among patients who received DOX compared with untreated patients remained elevated 5 years after diagnosis. CONCLUSION: When baseline HD was taken into account, chemotherapy, especially with anthracyclines, was associated with a substantially increased risk of CM. As the number of long-term survivors grows, identifying and minimizing the late effects of treatment will become increasingly important.  相似文献   
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Deficits in visual-spatial ability can be associated with Parkinson's disease (PD), and there are several possible reasons for these deficits. Dysfunction in frontal-striatal and/or frontal-parietal systems, associated with dopamine deficiency, might disrupt cognitive processes either supporting (e.g., working memory) or subserving visual-spatial computations. The goal of this study was to assess visual-spatial orientation ability in individuals with PD using the Mental Rotations Test (MRT), along with other measures of cognitive function. Non-demented men with PD were significantly less accurate on this test than matched control men. In contrast, women with PD performed similarly to matched control women, but both groups of women did not perform much better than chance. Further, mental rotation accuracy in men correlated with their executive skills involving mental processing and psychomotor speed. In women with PD, however, mental rotation accuracy correlated negatively with verbal memory, indicating that higher mental rotation performance was associated with lower ability in verbal memory. These results indicate that PD is associated with visual-spatial orientation deficits in men. Women with PD and control women both performed poorly on the MRT, possibly reflecting a floor effect. Although men and women with PD appear to engage different cognitive processes in this task, the reason for the sex difference remains to be elucidated.  相似文献   
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The conditioned taste aversion (CTA) is routinely used to assess the aversive consequences of anorexic agents, including potential pharmacological therapies for obesity. In a typical CTA paradigm, rats briefly sampling a novel tastant (e.g., saccharin) are acutely administered with toxin (e.g., lithium chloride, LiCl). After as few as one taste-toxin pairing, rats will reliably avoid the novel tastant. This paradigm is frequently used for the assessment of possible aversive consequences of drugs that are candidates for pharmacological therapies. The degree to which the drug supports development of a CTA is interpreted as an index of its aversive properties. Difficulties with previous work include the inability to assess affects on food intake and CTA simultaneously, particularly during chronic drug administration. We report here two novel CTA paradigms for the assessment of appetitive and aversive consequences of anorexic agents, simultaneously. In the first experiment, animals receive an intraoral infusion of a novel and highly palatable tastant immediately prior to administration of increasing doses of LiCl. In the second experiment, rats were implanted intraperitoneally with osmotic minipumps that chronically delivered a low dose of LiCl for 7 days. LiCl did not affect short or long term food intake in either experiment. However, LiCl did support the development of a CTA in both paradigms. These results suggest that both the appetitive and aversive consequences of anorexic agents can be assessed simultaneously during either acute or chronic drug administration.  相似文献   
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Global gene expression was analyzed in early and late collagen-induced arthritis (CIA). Of 8734 cDNAs analyzed, 330 were induced and 55 downregulated greater than twofold in early or late disease. Hierarchical clustering of these 385 cDNAs demonstrated five distinct expression patterns differentiating early from late disease and correlating with histopathologic changes in the paw. Of the 385 cDNAs, 185 are known, characterized genes, the majority of which are not described as playing a role in arthritis. However, several of these genes are involved in pathological processes relating to arthritis, including apoptosis, inflammation, and cellular proliferation. One interesting gene, follistatin-like gene, is highly expressed along the margin of contact between inflammatory synovial pannus and eroding bone, suggesting a role in joint destruction. These results demonstrate that global gene expression profiles distinguish early and late CIA and reveal several genes novel to arthritis the further characterization of which will advance our understanding of arthritis.  相似文献   
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