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PURPOSE: The impact of consensus recommendations for systemic therapy on outcome of disease is unclear. We evaluated if compliance with guidelines for systemic adjuvant treatment is associated with improved survival of women with node-negative breast cancer. PATIENTS AND METHODS: The study population included women diagnosed with invasive node-negative breast cancer in Québec, Canada, in 1988 to 1989, 1991 to 1992, and 1993 to 1994. Information was collected by chart review, linkage with administrative databases, and queries to attending physicians. Guidelines from the 1992 St Gallen conference were used as standard of care. Survival was estimated by Kaplan-Meier and Cox proportional hazards analyses. RESULTS: Among 1,541 women, 358 died before December 1999. Median follow-up was 6.8 years. Seven-year event-free and overall survivals were 66% and 81%, respectively. Survival was 88%, 84%, and 74% in women at minimal, moderate, or high risk of recurrence. Virtually all women at minimal risk were treated according to the consensus (98.4% of 370). In comparison, adjusted hazard ratios of death were 1.0 (95% CI, 0.6 to 1.7) and 2.3 (95% CI, 1.3 to 4.0) among women at moderate risk treated according to the consensus or not, respectively. Among women at high risk, adjusted hazard ratios of death were 2.0 (95% CI, 1.4 to 2.8) and 2.7 (95% CI, 1.9 to 3.9), respectively. Both risk category (P <.0005) and compliance with guidelines (P <.0005) were independent significant predictors of survival. CONCLUSION: Treatment according to consensus recommendations is associated with improved survival of women with breast cancer in the community. Promoting the adoption of guidelines for treatment is an effective strategy for disease control.  相似文献   
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PURPOSE: Up-regulation of both inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) enzymes has been reported in colorectal cancer. We aimed at evaluating the possible interaction between the nitric oxide and COX-2 pathways, and its effect on promoting tumor angiogenesis. EXPERIMENTAL DESIGN: Expression of iNOS, COX-2, vascular endothelial growth factor (VEGF), and CD31 was analyzed in tumor samples and corresponding normal mucosa obtained from 46 surgical specimens. We also evaluated iNOS activity, prostaglandin E(2) (PGE(2)), cyclic GMP and cyclic AMP production in the same specimens. Nitrite/nitrate levels, and PGE(2) and VEGF production were assessed in HCT116 and HT29 colon cancer cell lines after induction and selective inhibition of the two enzyme pathways. RESULTS: A significant correlation was found between iNOS and COX-2 immunohistochemical expression. PGE(2) production significantly correlated with iNOS activity and cGMP levels. A significant correlation was also found among PGE(2) production, microvessel density, and VEGF expression. Coinduction of both iNOS and COX-2 activities occurred after lipopolysaccharide (LPS) and epidermal growth factor (EGF) treatment in HCT116 and HT29 cells. Inhibition of iNOS by 1400W significantly reduced both LPS- and EGF-induced PGE(2) production. Treatment with LPS, EGF, and arachidonic acid significantly increased VEGF production in the iNOS-negative/COX-2-positive HT29 cells. This effect was completely reversed by treatment with the selective COX-2 inhibitor celecoxib. CONCLUSIONS: Our data showed a prominent role of nitric oxide in stimulating COX-2 activity in colorectal cancer. This interaction is likely to produce a cooperative effect in promoting angiogenesis through PGE(2)-mediated increase in VEGF production.  相似文献   
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Blood-borne distant metastasis is the leading cause of cancer-related death in breast cancer. The onset of this fundamental process can now be assessed in cancer patients using ultrasensitive immunocytochemical and molecular assays able to detect even single metastatic cells. Analyses of bone marrow (BM) samples show that disseminated cells are present in 20-40% of primary breast cancer patients without any clinical or histopathological signs of metastasis. The common homing of circulating breast cancer cells in BM is indicative for systemic tumor cell spread and predictive for growth of overt metastases in relevant organ sites such as bone, lung, or liver. Recent clinical studies involving more than 3000 breast cancer patients demonstrated that the presence of tumor cells in BM at primary diagnosis is an independent prognostic factor for unfavorable clinical outcome. To date, sampling of BM, however, is not a routine procedure in clinical management of breast cancer patients. Therefore, several research groups have developed sensitive assays for detection of circulating tumor cells in peripheral blood. Studies evaluating the clinical relevance of these blood assays are ongoing. Here, we will review the existing tumor cell assays and discuss their current clinical relevance and perspectives for the clinical management of breast cancer patients.  相似文献   
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Quality of life in tuberculosis: Patient and provider perspectives   总被引:8,自引:0,他引:8  
Tuberculosis (TB) is a persistent problem in the United States; however, little is known about its impact on functioning and quality of life (QOL) among people with TB. The purpose of this study is to describe the impact of TB on patients' QOL by using focus groups to assess the domains of QOL that are affected. Participants included patients (n = 10) who received treatment for active TB and physicians (n = 4) and nurses (n = 9) caring for patients with TB at a public health clinic in Baltimore, Maryland. TB affected all predicted domains of QOL, including general health perceptions, somatic sensation, psychological health, spiritual well-being, and physical, social and role functioning. Social stigmatization, isolation, pill burden, long duration of therapy, sexual dysfunction, loss of income, and fear were additional specific problems related to TB. Surprisingly, 11% (33) of the comments described benefits of TB illness, including increased spirituality and improved life perspectives. In addition, four additional QOL domains and three elements of treatment specific to TB which substantially impact QOL were identified. While patients and clinicians both identified issues in many areas of QOL, only patients mentioned the impact on sexual function, spirituality and improved life perspectives. Despite available curative therapy, TB and its treatment still have significant short and long-term consequences on patients' QOL.  相似文献   
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Background Recent epidemiologic data on travelers— diarrhea (TD) are essential for the evaluation of conventional and future prophylactic and therapeutic measures.
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve.  相似文献   
37.
Sentinox (STX) is an acid-oxidizing solution containing hypochlorous acid in spray whose virucidal activity against SARS-CoV-2 has been demonstrated. In this paper, results of a randomized controlled trial (RCT) on the efficacy of STX in reducing viral load in mild COVID-19 patients (NCT04909996) and a complementary in vitro study on its activity against different respiratory viruses are reported. In the RCT, 57 patients were randomized (1:1:1) to receive STX three (STX-3) or five (STX-5) times/day plus standard therapy or standard therapy only (controls). Compared with controls, the log10 load reduction in groups STX-3 and STX-5 was 1.02 (p = 0.14) and 0.18 (p = 0.80), respectively. These results were likely driven by outliers with extreme baseline viral loads. When considering subjects with baseline cycle threshold values of 20–30, STX-3 showed a significant (p = 0.016) 2.01 log10 reduction. The proportion of subjects that turned negative by the end of treatment (day 5) was significantly higher in the STX-3 group than in controls, suggesting a shorter virus clearance time. STX was safe and well-tolerated. In the in vitro study, ≥99.9% reduction in titers against common respiratory viruses was observed. STX is a safe device with large virucidal spectrum and may reduce viral loads in mild COVID-19 patients.  相似文献   
38.
Background

Recently developed convolutional neural network (CNN) models determine bone age more accurately than radiologists.

Objective

The purpose of this study was to determine whether a CNN and radiologists can accurately predict bone age from radiographs using only the index finger rather than the whole hand.

Materials and methods

We used a public anonymized dataset provided by the Radiological Society of North America (RSNA) pediatric bone age challenge. The dataset contains 12,611 hand radiographs for training and 200 radiographs for testing. The index finger was cropped from these images to create a second dataset. Separate CNN models were trained using the whole-hand radiographs and the cropped second-digit dataset using the consensus ground truth provided by the RSNA bone age challenge. Bone age determination using both models was compared with ground truth as provided by the RSNA dataset. Separately, three pediatric radiologists determined bone age from the whole-hand and index-finger radiographs, and the consensus was compared to the ground truth and CNN-model-determined bone ages.

Results

The mean absolute difference between the ground truth and CNN bone age for whole-hand and index-finger was similar (4.7 months vs. 5.1 months, P=0.14), and both values were significantly smaller than that for radiologist bone age determination from the single-finger radiographs (8.0 months, P<0.0001).

Conclusion

CNN-model-determined bone ages from index-finger radiographs are similar to whole-hand bone age interpreted by radiologists in the dataset, as well as a model trained on the whole-hand radiograph. In addition, the index-finger model performed better than the ground truth compared to subspecialty trained pediatric radiologists also using only the index finger to determine bone age. The radiologist interpreting bone age can use the second digit as a reliable starting point in their search pattern.

  相似文献   
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