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991.
Endometrial cancer (EC) incidence rates vary ~10-fold worldwide, in part due to variation in EC risk factor profiles. Using an EC risk model previously developed in the European EPIC cohort, we evaluated the prevention potential of modified EC risk factor patterns and whether differences in EC incidence between a European population and low-risk countries can be explained by differences in these patterns. Predicted EC incidence rates were estimated over 10 years of follow-up for the cohort before and after modifying risk factor profiles. Risk factors considered were: body mass index (BMI, kg/m2), use of postmenopausal hormone therapy (HT) and oral contraceptives (OC) (potentially modifiable); and, parity, ages at first birth, menarche and menopause (environmentally conditioned, but not readily modifiable). Modeled alterations in BMI (to all ≤23 kg/m2) and HT use (to all non-HT users) profiles resulted in a 30% reduction in predicted EC incidence rates; individually, longer duration of OC use (to all ≥10 years) resulted in a 42.5% reduction. Modeled changes in not readily modifiable exposures (i.e., those not contributing to prevention potential) resulted in ≤24.6% reduction in predicted EC incidence. Women in the lowest decile of a risk score based on the evaluated exposures had risk similar to a low risk countries; however, this was driven by relatively long use of OCs (median = 23 years). Our findings support avoidance of overweight BMI and of HT use as prevention strategies for EC in a European population; OC use must be considered in the context of benefits and risks.  相似文献   
992.
BackgroundAlthough treatment‐related lymphopenia (TRL) is common and associated with poorer survival in multiple solid malignancies, few data exist for anal cancer. We evaluated TRL and its association with survival in patients with anal cancer treated with chemoradiation (CRT).Materials and MethodsA retrospective analysis of 140 patients with nonmetastatic anal squamous cell carcinoma (SCC) treated with definitive CRT was performed. Total lymphocyte counts (TLC) at baseline and monthly intervals up to 12 months after initiating CRT were analyzed. Multivariable Cox regression analysis was performed to evaluate the association between overall survival (OS) and TRL, dichotomized by grade (G)4 TRL (<0.2k/μL) 2 months after initiating CRT. Kaplan‐Meier and log‐rank tests were used to compare OS between patients with versus without G4 TRL.ResultsMedian time of follow‐up was 55 months. Prior to CRT, 95% of patients had a normal TLC (>1k/μL). Two months after initiating CRT, there was a median of 71% reduction in TLC from baseline and 84% of patients had TRL: 11% G1, 31% G2, 34% G3, and 8% G4. On multivariable Cox model, G4 TRL at two months was associated with a 3.7‐fold increased risk of death. On log‐rank test, the 5‐year OS rate was 32% in the cohort with G4 TRL versus 86% in the cohort without G4 TRL.ConclusionTRL is common and may be another prognostic marker of OS in anal cancer patients treated with CRT. The association between TRL and OS suggests an important role of the host immunity in anal cancer outcomes.Implications for PracticeThis is the first detailed report demonstrating that standard chemoradiation (CRT) commonly results in treatment‐related lymphopenia (TRL), which may be associated with a poorer overall survival (OS) in patients with anal squamous cell carcinoma. The association between TRL and worse OS observed in this study supports the importance of host immunity in survival among patients with anal cancer. These findings encourage larger, prospective studies to further investigate TRL, its predictors, and its relationship with survival outcomes. Furthermore, the results of this study support ongoing efforts of clinical trials to investigate the potential role of immunotherapy in anal cancer.  相似文献   
993.
994.
INTRODUCTION: Late systemic right ventricular (RV) dysfunction after atrial redirection surgery is common. Patients may require cardiac transplantation in early adulthood. METHODS: We undertook cardiac resynchronisation (CRT)/defibrillator therapy in two patients as a bridge to transplantation. RESULTS: Two males (aged 24, 110 kg and 26 years, 106 kg); having undergone a Mustard procedure for dextro-transposition of the great arteries at 7 and 6 months of age respectively, presented with impaired systemic RV function and New York Heart Association III symptoms. Both patients had dual chamber pacemakers in-situ for sinus bradycardia. Upgrade to CRT was performed by conserving the existing endocardial leads and placement of epicardial electrodes. One demonstrated sustained improvement over a 24 month follow-up period. CONCLUSION: A hybrid CRT strategy is feasible in patients with failing systemic RVs and pre-existent endocardial dual chamber pacemakers. Appropriate patient selection criteria and optimum lead placement, however, still needs further evaluation in this population.  相似文献   
995.
Waldenstrom macroglobulinemia (WM) is an incurable low-grade lymphoma characterized by bone marrow (BM) involvement of IgM secreting lymphoplasmacytic cells. The induction of unfolded protein response (UPR) genes ("physiologic" UPR) enables cells to differentiate into professional secretory cells capable of production of high amounts of endoplasmic reticulum (ER)-processed proteins, such as immunoglobulins. Ultimately, the initially cytoprotective UPR triggers an apoptotic cascade if ER stress is not corrected, called proapoptotic/terminal UPR. We show that WM cells inherently express the physiologic UPR machinery compared with normal BM cells, and that increased ER stress leads to proapoptotic/terminal UPR in WM cells. We therefore examined tunicamycin, ER stress inducer, for potential antitumor effects in WM. Tunicamycin induced significant cytotoxicity, apoptosis and cell-cycle arrest, and inhibited DNA synthesis in WM cell lines and primary BM CD19(+) cells from patients with WM with an inhibitory concentration (IC(50)) of 0.5 microg/mL to 1 microg/mL, but not in healthy donor cells. Importantly, coculture of WM cells in the context of the BM microenvironment did not inhibit tunicamycin-induced cytotoxicity. Finally, we demonstrate that ER stress inducer synergizes with other agents used in the treatment of WM. These preclinical studies provide a framework for further evaluation of ER stress inducing agents as therapeutic agents in WM.  相似文献   
996.
Glutaraldehyde treated bovine tendon xenografts have been introduced into clinical trials as human knee ligament replacements recently, following animal experiments. This paper reports a further clinical study in which complications arose from implant debris. A laboratory study showed that the implants were not absorbed or integrated into the tissues of the host animals, as had been claimed by the originators. Mechanical tests of tendon reconstructions showed that the implants were not functional. It was concluded that this material is not suitable for clinical use within the knee joint as a cruciate ligament prosthesis.  相似文献   
997.
A technique has been described that uses a specially formed drill in the fabrication of removable dies. This technique is efficient and inexpensive, and it produces high-quality removable dies that are strong, stable, and accurately positioned.  相似文献   
998.
Intracerebral EEG (SEEG) recordings showing the development of fast rhythmic activity at seizure onset provide important evidence for the localisation of an epileptic focus. However, very high-frequency activity (greater than 50 Hz) of low amplitude relative to the background may not be apparent on the paper record due to the limited bandwidth and dynamic range of conventional SEEG recording and display methods. The use of a digital telemetry system with a fast sampling rate (400 Hz) and a wide dynamic range (1 microV resolution, 4 mV range) has allowed us to utilize expanded time scale SEEG plots and autoregressive spectral estimation to identify this activity in chronic SEEG studies. This may be particularly useful in frontal lobe epilepsy, where rapid propagation often prevents adequate localization using conventional methods of analysis.  相似文献   
999.
A review of postinfarction ventricular septal defects repaired surgically at Providence Hospital over the past 6 years is presented. Although this complication of myocardial infarction carries a high mortality rate, a lower rate can be achieved with early operative intervention. Preoperative pharmacologic reduction of preload, afterload, and intra-aortic balloon pumping are only temporizing measures to allow delineation of concomitant lesions. Operative mortality does not appear to be influenced by posterior location of the ventricular septal defects.  相似文献   
1000.
PURPOSE: Beginning in the 1980s, methotrexate has been used successfully to treat rheumatoid arthritis. The magnitude and severity of short- and long-term methotrexate toxicity, however, have not been adequately investigated. Our study was performed to determine the prevalence of hepatotoxicity in patients with rheumatoid arthritis receiving long-term methotrexate therapy. PATIENTS AND METHODS: We conducted a retrospective, computer-assisted review of all Duke University Medical Center patients undergoing liver biopsy for methotrexate monitoring from January 1979 to January 1988. A total of 538 biopsies were performed in 399 patients, 259 of whom had inflammatory arthritis (210 with rheumatoid arthritis, 47 with psoriatic arthritis, and two with seronegative spondyloarthropathy). RESULTS: No evidence of cirrhosis was defined in the cohort with rheumatoid arthritis; however, six patients with rheumatoid arthritis had histologic changes of fibrotic liver disease (prevalence of 2.9 percent in the group with rheumatoid arthritis) while taking methotrexate. Five of the six patients were obese and three had glucose intolerance or overt diabetes mellitus, and one person admitted to alcohol usage. Only one patient with fibrotic liver disease had elevated liver function test results, and no person showed a declining serum albumin level at the time of biopsy. Sixty-one patients with rheumatoid arthritis underwent multiple samplings (44 with two, 13 with three, and four with four biopsies). Fourteen of these patients showed progressive hepatic disease, whereas four patients improved. CONCLUSION: Although the prevalence of methotrexate hepatotoxicity in this large cohort of patients with rheumatoid arthritis was low, a small but definite risk of hepatic fibrosis, not predictable by laboratory screening, still exists.  相似文献   
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