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排序方式: 共有6919条查询结果,搜索用时 421 毫秒
1.
Sami Akbulut Abdirahman Sakulen Hargura Ibrahim Umar Garzali Ali Aloun Cemil Colak 《World Journal of Clinical Cases》2022,10(26):9228-9240
Management of colorectal cancer (CRC) was severely affected by the changes implemented during the pandemic, and this resulted in delayed elective presentation, increased emergency presentation, reduced screening and delayed definitive therapy. This review was conducted to analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic on management of CRC and to identify the changes made in order to adapt to the pandemic. We performed a literature search in PubMed, Medline, Index Medicus, EMBASE, SCOPUS, Reference Citation Analysis (https://www.referencecitationanalysis.com/) and Google Scholar using the following keywords in various combinations: Colorectal cancer, elective surgery, emergency surgery, stage upgrading, screening, surveillance and the COVID-19 pandemic. Only studies published in English were included. To curtail the spread of COVID-19 infection, there were modifications made in the management of CRC. Screening was limited to high risk individuals, and the screening tests of choice during the pandemic were fecal occult blood test, fecal immunochemical test and stool DNA testing. The use of capsule colonoscopy and open access colonoscopy was also encouraged. Blood-based tests like serum methylated septin 9 were also encouraged for screening of CRC during the pandemic. The presentation of CRC was also affected by the pandemic with more patients presenting with emergencies like obstruction and perforation. Stage migration was also observed during the pandemic with more patients presenting with more advanced tumors. The operative therapy of CRC was altered by the pandemic as more emergencies surgeries were done, which may require exteriorization by stoma. This was to reduce the morbidity associated with anastomosis and encourage early discharge from the hospital. There was also an initial reduction in laparoscopic surgical procedures due to the fear of aerosols and COVID-19 infection. As we gradually come out of the pandemic, we should remember the lessons learned and continue to apply them even after the pandemic passes. 相似文献
2.
《Cancer radiothérapie》2022,26(4):547-556
PurposeSurface-guided radiotherapy is useful for the pre-positioning and monitoring of radiotherapy. The purpose of this study was to investigate the impact of surface guidance on the repeatability of patient localization and to estimate the specific point at which high positional errors occur.Materials and methodsTen patients without the VOXELAN system (non-VXLN group) and 10 patients with the VOXELAN as the pre-positioning procedure (VXLN group) were included in this analysis. Twelve regions of interest (ROI) were defined in all the patients to verify any misalignment during radiotherapy. Thirteen ROIs were defined on the isocenter.ResultsCompared with the non-VXLN group, the translational positional errors of the VXLN group were the same for all the ROIs. The mean translational positional errors of the VXLN group in the longitudinal direction were approximately 0.1 mm, and the standard deviation was the largest among the three directions in all the ROIs. The magnitude of the standard deviation in the non-VXLN group varied independently of the ROI and direction. The standard deviations of the VXLN group in the longitudinal direction were large in all the ROIs, while the standard deviations in the vertical and lateral directions were small.ConclusionPre-positioning with a surface guidance system reduced the body twist and rotation, which could not be corrected by image-guided radiotherapy alone. Since the VOXELAN can detect positioning errors quickly and without additional radiation exposure to the patient, it can be used as a tool for pre-positioning in radiotherapy. 相似文献
3.
《Research in social & administrative pharmacy》2022,18(9):3694-3698
In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area. 相似文献
4.
目的:探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1(Ang-1)mRNA、血管内皮生长因子(VEGF)mRNA的表达和定位的影响。方法:24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组,每组6只,用米非司酮建立胚胎着床障碍动物模型,各组给予相应药物灌胃,妊娠第5天处死小鼠后,检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果:模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组(均P<0.05);与模型组比较,二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高(均P<0.05)。结论:二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量,促进子宫内膜血管生成,从而提高子宫内膜容受性。 相似文献
5.
Heather G. Lyu MD Adil H. Haider MD MPH Adam B. Landman MD MS MIS MHS Chandrajit P. Raut MD MSc 《Cancer》2019,125(17):2926-2934
The rarity and heterogeneity of sarcomas make performing appropriately powered studies challenging and magnify the significance of large databases in sarcoma research. Established large tumor registries and population-based databases have become increasingly relevant for answering clinical questions regarding sarcoma incidence, treatment patterns, and outcomes. However, the validity of large databases has been questioned and scrutinized because of the inaccuracy and wide variability of coding practices and the absence of clinically relevant variables. In addition, the utilization of large databases for the study of rare cancers such as sarcoma may be particularly challenging because of the known limitations of administrative data and poor overall data quality. Currently, there are several large national cancer databases, including the Surveillance, Epidemiology, and End Results database, the National Cancer Data Base of the American College of Surgeons and the American Cancer Society, and the National Program of Cancer Registries of the Centers for Disease Control and Prevention. These databases are often used for sarcoma research, but they are limited by their dependence on administrative or billing data, the lack of agreement between chart abstractors on diagnosis codes, and the use of preexisting documented hospital diagnosis codes for tumor registries, which lead to a significant underestimation of sarcomas in large data sets. Current and future initiatives to improve databases and big data applications for sarcoma research include increasing the utilization of sarcoma-specific registries and encouraging national initiatives to expand on real-world, evidence-based data sets. 相似文献
6.
《Clinical breast cancer》2019,19(3):e422-e427
IntroductionPartial breast reconstruction (PBR) using chest wall perforator flaps (CWPF) allows for excision of tumors in the outer quadrant of the breast in women with small to moderate non-ptotic breasts resulting in a good aesthetic outcome. There are limited data available in the literature regarding long-term follow-up and the effect of CWPF on subsequent surveillance mammographic interpretation and recall rates. A retrospective audit with qualitative analysis of initial mammograms was performed to assess this.Patients and MethodsThis retrospective analysis of a prospectively maintained database included all consecutive patients who underwent either PBR with CWPF or wide local excision (WLE) between January 2013 and December 2014 by a single surgeon in a tertiary referral center. Qualitative analysis of the postoperative mammograms was performed after review by 2 blinded radiologists.ResultsThirty-six patients were included in the study, 18 in each arm. The CWPF group was younger and had larger tumor size anticipated on preoperative imaging, which correlated with larger specimens excised. Both groups were comparable with respect to tumor pathological characteristics. Comparing the first postoperative mammograms, both groups were similar in features reported such as calcifications, fat necrosis, volume loss, and radiotherapy changes. During the follow-up period (median 4 years), 138 surveillance mammograms were performed. One patient was recalled for further imaging in the CWPF group. There was no significant difference in the need for diagnostic imaging and biopsy between the groups.ConclusionPatients who underwent PBR using CWPF had similar features on postoperative surveillance mammograms compared with that post WLE. 相似文献
7.
《European journal of surgical oncology》2020,46(6):982-990
IntroductionLung cancer is the leading cause of cancer-death worldwide. The U.S. Preventative Services Task Force (USPTSF) approved screening for current or former smokers aged 55–80 based on the results of the National Lung Screening trial (NLST). Following the NLST, new evidence has emerged from clinical trials and updates to previous trials prior to the anticipated update to the USPSTF guideline. We review the new evidence on lung cancer screening with low dose computed tomography (LDCT) and the surgical implications.MethodsA review of new literature was performed pertaining to lung cancer screening since implementation of UPSTF guidelines. Articles for inclusion were identified by both authors’, then search of the Pubmed and Cochrane database was performed from January 1st, 2013 through February 4th, 2020 using the MeSH search terms: “lung cancer”; “screening”; “low dose CT”. The results of these studies are summarized.ResultsWe identified multiple prospective randomized control trials and meta-analysis since the NLST supporting lung cancer-specific mortality with screening. We identified new nodule classification systems and the development of risk-models which may reduce false positive rates and identify high risk patients not currently eligible for screening. Finally, we discussed the surgical implications of screening.ConclusionNew data supports NLST findings and show ongoing benefit to LDCT for lung cancer screening. Standardized LDCT screening classification has been shown to reduce harm and lower false positive rates. Further study is needed regarding use of risk-modeling. Screening will require an increase in the thoracic workforce to accommodate the amount of surgically operable cancers. 相似文献
8.
近年来,环境监测、疾病监测等各种监测网络不断健全,监测系统成为开展生态学研究的重要数据来源。监测数据类型包括了横断面数据、时间序列数据和面板数据,涉及暴露、结局和混杂3个维度。针对该数据的信息属性和结构特点,相关统计学方法逐渐发展完善,出现了一些新的方法、模型。基于数据的时空属性,本文对监测数据在生态学研究中常用模型的原理、适用条件及优劣进行了综述。 相似文献
9.
10.
Susie Dzakpasu Paromita Deb-Rinker Laura Arbour Elizabeth K. Darling Michael S. Kramer Shiliang Liu Wei Luo Phil A. Murphy Chantal Nelson Joel G. Ray Heather Scott Michiel VandenHof K.S. Joseph 《Journal d'obstetrique et gynecologie du Canada》2019,41(11):1589-1598.e16
ObjectiveThis study sought to quantify temporal trends and provincial and territorial variations in severe maternal morbidity (SMM) in Canada.MethodsThe study used data on all hospital deliveries in Canada (excluding Québec) from 2003 to 2016 to examine temporal trends and from 2012 to 2016 to study regional variations. SMM was identified using diagnosis and intervention codes. Contrasts among periods and regions were quantified using rate ratios (RRs) and 95% confidence intervals (CIs). Temporal changes were also assessed using chi-square tests for trend (Canadian Task Force Classification II-1).ResultsThe study population included 3 882 790 deliveries between 2003 and 2016 and 1 418 545 deliveries between 2012 and 2016. Severe hemorrhage rates increased from 44.8 in 2003 to 62.4 per 10 000 deliveries in 2012 (P for trend <0.0001) and then declined to 41.8 per 10 000 deliveries in 2016 (P for trend <0.0001). Maternal intensive care unit admission and sepsis rates decreased between 2003 and 2016, whereas rates of stroke, severe uterine rupture, hysterectomy, obstetric embolism, shock, and assisted ventilation increased. Rates of composite SMM in 2012-2016 were higher in Newfoundland and Labrador (RR 1.15; 95% CI 1.04–1.26), Nova Scotia (RR 1.11; 95% CI 1.03–1.19), New Brunswick (RR1.22; 95% CI 1.13–1.32), Manitoba (RR 1.09; 95% CI 1.03–1.15), Saskatchewan (RR 1.15; 95% CI 1.09–1.22), the Yukon (RR 1.74; 95% CI 1.35–2.25), and Nunavut (RR 1.76; 95% CI 1.46–2.11) compared with the rest of Canada, whereas rates were lower in Alberta and British Columbia.ConclusionThis surveillance report helps inform clinical practice and public health policy for improving maternal health in Canada. 相似文献