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Local treatment options for ductal carcinoma in situ (DCIS) are virtually identical to those for early invasive breast cancer, despite the fact that the survival from this condition is much higher. Our ability to more appropriately tailor therapy for DCIS is hampered by a lack of understanding of the natural history of DCIS, our limited ability to predict the rate of progression to invasive cancer and the response to therapy, and the absence of tools to follow patients who have not had invasive treatments. Neoadjuvant therapy, which has been proven to be both safe and effective in tailoring treatments for invasive cancer, could be ideally suited to DCIS. However, neoadjuvant therapy requires that doctors and patients delay surgical treatment that has known benefits. In order to successfully introduce this approach into clinical practice, risk assessment and decision support tools will be needed to help physicians and patients feel comfortable that they are not being exposed to unnecessary or excessive risk. In addition, we need better imaging to track extent and progression of disease. Among the possible benefits of the neoadjuvant approach, we may discover that many lesions are responsive and some even reversible, leaving us with treatments that might be tailored to biology and with important clues for breast cancer prevention in high-risk women.  相似文献   
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FT Chew  DYT Goh  BC Ooi  R Saharom  JKS Hui  BW Lee 《Allergy》1999,54(4):320-329
BACKGROUND: Air-pollution levels have been shown to be associated with increased morbidity of respiratory diseases. METHODS: Data for ambient air-pollutant levels, meteorologic factors, and hospitalization or emergency room (ER) visits for acute asthma in Singapore children over a 5-year period (1990-4) were obtained and analyzed for associations by time-series methods. RESULTS: Throughout this period, the annual mean and 24-h mean levels for sulfur dioxide (SO2), nitrogen dioxide (NO2), and total suspended particles (TSP) and maximum 1-h daily average for ozone were generally within the air-quality guidelines established by the World Health Organization (WHO). However, positive correlation between levels of each of these pollutants and daily ER visits for asthma was observed in children aged 3-12 years, but not among adolescents and young adults (13-21 years old). The association with SO2 and TSP persisted after standardization for meteorologic and temporal variables. An adjusted increase in 2.9 ER visits for every 20 microg/m3 increase in atmospheric SO2 levels, lagged by 1 day, was observed on days when levels were above 68 microg/m3. With TSP, an adjusted increase of 5.80 ER visits for every 20 microg/m3 increase in its daily atmospheric levels, lagged by 1 day, was observed on days with levels above 73 microg/m3. Similar results were also obtained after controlling for autocorrelation by time-series analysis. CONCLUSIONS: These associations were observed even though the overall levels of all pollutants were generally within the air-quality guidelines established by the WHO. These findings suggest that asthmatic children are susceptible to increased levels of air pollutants, particularly SO2 and TSP, although the ambient levels are generally within "acceptable" ranges.  相似文献   
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DNA polymorphisms among independent isolates of herpes simplex virus (HSV) type 1 were studied from a 7-year-old male patient with recurrent infections of the skin and internal organs. In the patient's serum, HSV antibodies could not be detected by complement fixation, enzyme-linked immunosorbent assay (ELISA), or neutralization tests. ELISA tests for the presence of antibodies to human immunodeficiency virus were also negative. One HSV isolate was obtained from mesenteric nodes biopsied in 1983; one from skin in 1984; and three (postmortem) from brain, lungs, and liver in 1985. Restriction enzymes Eco RI, Bgl II, Hind III, Kpn I, and Bam H1 digestion patterns of the five isolates were similar. However, Sal I digests of isolates from skin, mesenteric nodes, lungs, and liver showed variations that were distinct from that of the brain isolate. Although Sal I digests of skin, mesenteric nodes, lungs, and liver isolates share a common variation in lacking F and G, the liver isolate can be further differentiated because of the gain of a restriction site on the H fragment. Thus, the three distinct variants observed were the isolates from brain (variant 1); from skin, mesenteric nodes, and lungs (variant 2); and from liver (variant 3). The fragments involved in variations among these isolates (presence or absence of Sal, G and H) are from the unique short and long regions (invariable regions) of the genome and therefore do not show heterogeneity in size. The extent of variation among these isolates is less than that seen among epidemiologically unrelated strains, suggesting that they originated from a single infecting strain, probably the brain isolate.  相似文献   
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OBJECTIVE: Assess the effectiveness and cost-effectiveness of using biomarkers and risk assessment tools to stratify women for breast cancer preventive interventions.METHODS: A Markov model was developed to compare risk management strategies for high-risk women considering chemoprevention. Annual screening is compared to the use of chemoprevention for all women and the use of risk assessment technologies to stratify patients for chemoprevention. The biomarker atypia was used to stratify women by risk. Random fine-needle aspiration (rFNA) and ductal lavage (DL) were evaluated and compared as the risk assessment tools used to discover atypia. Sensitivity analyses explore assumptions regarding the prognostic and predictive characteristics of atypia, both the relative breast cancer risk and benefit from chemoprevention women with atypia incur.RESULTS: Risk assessment strategies using rFNA or DL in combination with chemoprevention are found to be cost-effective (<$50,000 per life year saved) in high-risk groups under most scenarios. Both strategies were more effective and less costly in younger cohorts. Effectiveness of the risk assessment strategies increased when higher risk and increased benefit from chemoprevention were associated with atypia. Within the scenarios tested, rFNA is less costly than DL.CONCLUSION: rFNA and DL appear to be cost-effective in high-risk women, assuming women with detected atypia choose tamoxifen. The tools are largely effective for women who are not motivated to take tamoxifen but would be if atypia were found. As biomarker risk assessment tools better predict the risk of breast cancer and or benefit of interventions, their cost-effectiveness increases.  相似文献   
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OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age.  相似文献   
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