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101.
OBJECTIVE: Many new stool tests intended to detect neoplastic cells or cell products are developed at present for colorectal cancer (CRC) screening. The aim of this study was to simulate a population-based screening setting to assess and compare the potential for early detection and prevention of CRC of screening based on stool tests with different sensitivity and specificity and of screening with colonoscopy as a primary screening tool. METHOD: A Markov model was developed aimed to estimate the proportion of CRC cases which are early detected or prevented due to screening as well as the number of equired stool tests and colonoscopies per early detected or prevented CRC case. Model outcomes were calculated for the offer of annual stool testing from age 55 to 74 in combination with colonoscopic follow-up of positive test results and for the offer of screening colonoscopy as a primary screening tool at ages 55 and 65. The long-lasting risk reduction of colonoscopy allowing the removal of precancerous lesions was taken into account quantitatively. RESULTS: For a variety of stool tests with different performance characteristics, the proportion of CRC cases early detected or prevented was estimated to be higher for stool testing in combination with colonoscopic follow-up of positive test results compared with screening colonoscopy assuming levels of compliance to be expected for the respective screening scheme. Optimizing performance characteristics of stool tests in terms of detecting precancerous lesions, in addition to those in terms of detecting CRC, seemed to be crucial for maximizing effectiveness of CRC screening with stool tests. CONCLUSION: Screening based on new stool tests with colonoscopic follow-up of positive test results might offer a high potential for early detection or prevention of CRC.  相似文献   
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BACKGROUND: Over the last decades, long-term survival rates have substantially increased for many forms of cancer. However, these improvements have often been detected with substantial delay by traditional methods of survival analyses. PATIENTS AND METHODS: Using data of the population-based Saarland Cancer Registry, 5- and 10-year relative survival rates were derived for patients with 24 common forms of cancer in Saarland/Germany for the years 2000-2002 by period analysis and compared with conventional cohort estimates of 5- and 10-year relative survival rates pertaining to patients diagnosed in 1990-1992. RESULTS: For many forms of cancer, the 2000-2002 period survival estimates were substantially higher than the corresponding estimates for the cohorts of patients diagnosed in 1990-1992. For example, 10-year relative survival rates achieved in 2000-2002 were close to 100% for patients with testis and thyroid cancer, >85% for patients with melanomas of the skin, approximately 80% for patients with endometrial cancer and prostate cancer, close to 70% for patients with breast cancer and kidney cancer, and close to 60% for patients with colon cancer and lymphomas. CONCLUSIONS: Survival expectations of patients diagnosed with cancer at the beginning of the third millenium are substantially higher than previously available survival statistics have suggested.  相似文献   
103.
Endoscopic screening (sigmoidoscopy, colonoscopy) with removal of precancerous lesions can prevent a large proportion of colorectal cancers (CRCs). However, there is lack of data regarding optimal age, time intervals and numbers of screening examinations. We developed and applied modified techniques of epidemiological analysis to evaluate the impact of various endoscopy-based screening strategies on prevention of clinically manifest CRCs between the ages of 50 and 79 in a population-based case-control study (294 cases, 254 controls) conducted in Saarland, Germany. We found a strong potential for reduction of CRC occurrence even with a single screening endoscopy. The optimal age for a single screening endoscopy appears to be around 55 (estimated potential for prevention of cases between the ages of 55 and 79 in case of 100% compliance: 77% (95% confidence interval (CI) 46-90%)). A single screening endoscopy at age 50 would have a lower impact due to failure to prevent CRC at higher ages. Similarly, screening at ages 60 or older would have a lower impact because it would fail to prevent CRC at lower ages. Repeated offers of screening examinations could provide substantial additional benefit with the levels of compliance to be expected in practice, but they would have to be weighed against the increased risks and costs.  相似文献   
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The effect of renal impairment (RI) on risk of bleeding and recurrent thrombosis in cancer patients treated with direct oral anticoagulants for venous thromboembolism (VTE) is undefined. We ran a prespecified analysis of the randomized Caravaggio study to evaluate the role of RI as a risk factor for bleeding or recurrence in patients treated with dalteparin or apixaban for cancer-associated VTE. RI was graded as moderate (creatinine clearance between 30-59 mL/minute; 275 patients) and mild (between 60-89 mL/minute; 444 patients). In the 1142 patients included in this analysis, the incidence of major bleeding was similar in patients with moderate vs. no or mild RI (HR 1.06-95% CI: 0.53-2.11), with no difference in the relative safety of apixaban and dalteparin. Recurrent VTE was not different in moderate vs. no or mild RI (HR=0.67, 95% CI: 0.38-1.20); in moderate RI, apixaban reduced recurrent VTE compared to dalteparin (HR=0.27, 95% CI: 0.08-0.96; P for interaction 0.1085). At multivariate analysis, no association was found between variation of renal function over time and major bleeding or recurrent VTE. Advanced or metastatic cancer was the only independent predictor of major bleeding (HR=2.84, 95% CI: 1.20-6.71), with no effect of treatment with apixaban or dalteparin. In our study, in cancer patients treated with apixaban or dalteparin, moderate RI was not associated with major bleeding or recurrent VTE. In patients with moderate renal failure, the safety profile of apixaban was confirmed with the potential for improved efficacy in comparison to dalteparin. ClinicalTrials.gov identifier: NCT03045406.  相似文献   
107.
Previous work suggests two mechanisms whereby finding enjoyment in life decreases the likelihood of depressive affect: (a) enjoyment counteracts depressive affect and (b) failure to find enjoyment is itself a stimulus for depressive affect. The present study, based on interviews with 2168 adults in two communities, yields findings which are consistent with the proposition that satisfaction with major life areas is a factor in finding enjoyment in life, thereby a factor in avoiding depressive affect and thereby a factor in avoiding psycho-physiologic problems. Thus the present study provides a measure of support for the proposition that finding enjoyment in life reduces the likelihood of depressive affect and for the corollary of this proposition, that social, psychological, and other factors in the enjoyment of life are thereby also factors in depressive affect and its consequences.  相似文献   
108.
Human natural killer (NK) cells are large granular lymphocytes that constitutively express functional forms of the interleukin-2 receptor (IL-2R) and lyse tumor and virally infected cells without prior sensitization. NK cells with high density expression of CD56 (CD56bright) express the high affinity IL-2R and proliferate in response to low (picomolar) concentrations of IL-2. CD56dim NK cells express the intermediate affinity IL-2R and demonstrate enhanced cytotoxic activity without proliferation in response to high (nanomolar) concentrations of IL-2. In the present study, we characterized IL-10R expression on human NK cells and the functional consequences of IL-10 binding directly to highly purified subsets of CD56bright and CD56dim NK cells. Binding studies using 125I-IL-10 indicated that resting human NK cells constitutively express the IL-10 receptor protein at a surface density of approximately 90 receptor sites per cell, with a kd of approximately 1 nmol/L. Alone, IL-10 did not induce proliferation of CD56bright or CD56dim NK cell subsets. However, at low concentrations (0.5 to 5 ng/mL), IL-10 significantly augmented IL-2-induced proliferation of the CD56bright NK cell subset mediated via the high-affinity IL-2R. In the absence of IL-2, IL-10 was able to induce significant NK cytotoxic activity against NK-resistant tumor cell targets in both subsets of NK cells in a dose-dependent fashion. Furthermore, the combination of IL-10 and IL-2 had an additive effect on NK cytotoxic activity, whereas that of IL-10 and IL-12 did not. Production of interferon-gamma, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor by IL-2-activated NK cells was also significantly enhanced by IL-10. Neither resting nor activated human NK cells appear to produce human IL-10 protein. In summary, NK cells constitutively express the IL-10R protein in low density, and the functional consequences of IL-10 binding directly to human NK cell subsets appear to be stimulatory and dose-dependent. In contrast to its direct effects on human T cells and monocytes/macrophages, IL-10 potentiates cytokine production by human NK cells.  相似文献   
109.
Bile acid sequestrants (BAS) lower plasma low density lipoprotein levels and improve glycemic control. Colestimide, a BAS, has been claimed by computed tomography to reduce liver fat. Therefore, we examined the efficacy of colesevelam, a potent BAS, to decrease liver fat in patients with biopsy-proven nonalcoholic steatohepatitis (NASH). Liver fat was measured by a novel magnetic resonance imaging (MRI) technique, the proton-density-fat-fraction (PDFF), as well as by conventional MR spectroscopy (MRS). Fifty patients with biopsy-proven NASH were randomly assigned to either colesevelam 3.75 g/day orally or placebo for 24 weeks. The primary outcome was change in liver fat as measured by MRI-PDFF in colocalized regions of interest within each of the nine liver segments. Compared with placebo, colesevelam increased liver fat by MRI-PDFF in all nine segments of the liver with a mean difference of 5.6% (P = 0.002). We cross-validated the MRI-PDFF-determined fat content with that assessed by colocalized MRS; the latter showed a mean difference of 4.9% (P = 0.014) in liver fat between the colesevelam and the placebo arms. MRI-PDFF correlated strongly with MRS-determined hepatic fat content (r(2) = 0.96, P < 0.0001). Liver biopsy assessment of steatosis, cellular injury, and lobular inflammation did not detect any effect of treatment. Conclusion: Colesevelam increases liver fat in patients with NASH as assessed by MRI as well as MRS without significant changes seen on histology. Thus, MRI and MRS may be better than histology to detect longitudinal changes in hepatic fat in NASH. Underlying mechanisms and whether the small MR-detected increase in liver fat has clinical consequences is not known. (HEPATOLOGY 2012;56:922-932).  相似文献   
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