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1.
The use of radiation for primary liver cancers has historically been limited because of the risk of radiation-induced liver disease. Treatment fields have become more conformal because of several technical advances, and this has allowed for dose escalation. Stereotactic body radiation therapy (SBRT), also known as stereotactic ablative radiotherapy, is now able to safely treat liver tumors to ablative doses while sparing functional liver parenchyma by using highly conformal therapy. Several retrospective and small prospective studies have examined the use of SBRT for liver cancers; however, there is a lack of well-powered randomized studies to definitively guide management in these settings. Recent advances in systemic therapy for primary liver cancers have improved outcomes; however, the optimal selection criteria for SBRT as a local therapy remain unclear among other liver-directed options such as radiofrequency ablation, transarterial chemoembolization, and radioembolization.  相似文献   
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Background

Poland introduced the 10-valent conjugate pneumococcal vaccine (PCV10) into the childhood immunization program in January 2017. During previous decades, considerable changes had occurred in the surveillance system for invasive pneumococcal disease. Therefore, to provide baseline data on pneumococcal diseases before PCV10 introduction, we evaluated the epidemiology of pneumococcal meningitis (PM), the only syndrome monitored consistently since 1970.

Methods

Based on laboratory-confirmed cases reported during 2005-2015, we calculated the reported rates, serotypes distribution and antimicrobial resistance of pneumococcal meningitis isolates. Data from the mandatory national surveillance system was linked with data on cerebrospinal fluid isolates submitted to the National Reference Centre for Bacterial Meningitis. We used negative binomial regression with Newey West method to test for trend in rates of pneumococcal meningitis notified during 2005-2015 and Chi-squared test to assess changes in the serotype distribution from 2008-2011 to 2012-2015.

Results

From 2005 to 2015, the overall reported incidence of PM increased from 0.21 to 0.47 cases per 100,000 population, average yearly increase of 7% (rate ratio 1.07; 95% CI 1.06–1.08). The increase was primarily due to annual increase of 3% (1.02–1.05) among 15–49?years of age, 12% (95% CI: 1.10–1.13) among 50–64?years of age, 18% (95% CI: 1.16–1.19) among persons 65–74?years of age and 9% (95% CI 1.07–1.10) among persons ≥75?years of age. In children <5?years of age, serotypes included in PCV10 and PCV13 accounted for 75% and 80% of reported isolates, respectively. From 2008-2011 to 2012-2015, the proportion of PM cases caused by PCV10 serotypes decreased from 52% to 41% (p?<?0.01). Overall, 28% of isolates were resistant to penicillin and 13% were non-susceptible to cefotaxime.

Conclusions

The introduction of PCV10 into national immunization program may have considerable impact on disease burden, especially on number of cases caused by isolates non-susceptible to antimicrobials.  相似文献   
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Treatment guidelines recommend the routine use of point-of-care diagnostic tests for coagulopathy in the management of cardiac surgery patients at risk of severe bleeding despite uncertainty as to their diagnostic accuracy. We performed a systematic review and meta-analysis of studies that evaluated the diagnostic accuracy of viscoelastometry, platelet function tests, and modified thromboelastography (TEG) tests, for coagulopathy in cardiac surgery patients. The reference standard included resternotomy for bleeding, transfusion of non-red cell components, or massive transfusion. We searched MEDLINE, EMBASE, CINAHL, and Clinical Trials.gov, from inception to June 2019. Study quality was assessed using QUADAS-2. Bivariate models were used to estimate summary sensitivity and specificity with (95% confidence intervals). All 29 studies (7440 participants) included in the data synthesis evaluated the tests as predictors of bleeding. No study evaluated their role in the management of bleeding. None was at low risk of bias. Four were judged as low concern regarding applicability. Pooled estimates of diagnostic accuracy were; Viscoelastic tests, 12 studies, sensitivity 0.61 (0.44, 0.76), specificity 0.83 (0.70, 0.91) with significant heterogeneity. Platelet function tests, 12 studies, sensitivity 0.63 (0.53, 0.72), specificity 0.75 (0.64, 0.84) with significant heterogeneity. TEG modification tests, 3 studies, sensitivity 0.80 (0.67, 0.89), specificity 0.76 (0.69, 0.82) with no evidence of heterogeneity. Studies reporting the highest values for sensitivity and specificity had important methodological limitations. In conclusion, we did not demonstrate predictive accuracy for commonly used point-of-care devices for coagulopathic bleeding in cardiac surgery. However, the certainty of the evidence was low.  相似文献   
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This research investigated the effects of different thermoplastics types and different kinds of straw on selected properties of polymer-straw boards. Polyethylene, polyethylene, and polystyrene of virgin and of recycled origin were used for bonding the boards. Three kinds of straw were used: rape (Brassica napus L. var. napus), triticale (Triticosecale Witt b m.), and rye (Secale L.). Five-layer polymer-straw boards were produced. The obtained boards differed in both the materials they were made of and the moisture content (7, 25, and 2% for the core, the middle, and the face layers, respectively), and 30% of straw particles were substituted with thermoplastics added to the face layers. It was found that properties of polymer-straw boards strongly depend on both the kind of straw and the type of polymer used. The best mechanical properties were obtained for rye straw and polystyrene or recycled polymers, whereas the best hydrophobic properties were observed for rape straw combined with recycled polyethylene or polypropylene. Although recycled polymers improved the hydrophobic properties of the boards, they impaired their mechanical properties in comparison with the reference ones. However, in terms of bending strength, they still met the requirements for heavy duty load-bearing boards for use in humid conditions (20 MPa for P7 boards according to EN 312).  相似文献   
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