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101.
Colorectal cancer (CRC) was the second-ranked worldwide type of cancer during 2020 due to the crude mortality rate of 12.0 per 100000 inhabitants. It can be prevented if glandular tissue (adenomatous polyps) is detected early. Colonoscopy has been strongly recommended as a screening test for both early cancer and adenomatous polyps. However, it has some limitations that include the high polyp miss rate for smaller (< 10 mm) or flat polyps, which are easily missed during visual inspection. Due to the rapid advancement of technology, artificial intelligence (AI) has been a thriving area in different fields, including medicine. Particularly, in gastroenterology AI software has been included in computer-aided systems for diagnosis and to improve the assertiveness of automatic polyp detection and its classification as a preventive method for CRC. This article provides an overview of recent research focusing on AI tools and their applications in the early detection of CRC and adenomatous polyps, as well as an insightful analysis of the main advantages and misconceptions in the field.  相似文献   
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《Vaccine》2021,39(33):4742-4750
Allogeneic hematopoietic stem cell transplantation (alloHSCT) results in a loss of humoral immunity and subsequent risk for severe infections. Thus, re-vaccination is required but may fail due to incomplete immune reconstitution. We retrospectively analyzed predictors of immune response to primary vaccination applied according to the EBMT (European Blood and Marrow Transplantation Group) recommendations. Serologic response to vaccination against diphtheria (D), tetanus (T), Bordetella pertussis (aP) and Haemophilus influenzae (Hib) (administrated as combined DTaP-Hib-IPV vaccination) was studied in 84 alloHSCT patients transplanted between 2008 and 2015 (age at alloHSCT: 18.6–70.6 years). All patients with a relapse-free survival of ≥9 months, at least 3 consecutive vaccinations and absence of intravenous immunoglobulin administration within 3 months before and after vaccination met the primary inclusion criteria. Additionally, immunological response to a pneumococcal conjugate vaccine was analyzed in a subgroup of 67 patients. Patients’ characteristics at the time of first vaccination were recorded. Responses were measured as vaccine-specific antibody titers. Regarding DTaP-Hib-IPV vaccination, 89.3% (n = 75) of all patients achieved protective titers to at least 3 of the 4 vaccine components and were thus considered responders. 10.7% (n = 9) of the patients were classified as non-responders with positive immune response to less than 3 components. Highest response was observed for Hib (97.4%), tetanus (95.2%) and pneumococcal vaccination (83.6%) while only 68.3% responded to vaccination against Bordetella pertussis. Significant risk factors for failure of vaccination response included low B cell counts (p < 0.001; cut-off: 0.05 B cells/nl) and low IgG levels (p = 0.026; mean IgG of responders 816 mg/dl vs. 475 mg/dl of non-responders). Further, a trend was observed that prior cGvHD impairs vaccination response as 88.9% of the non-responders but only 54.7% of the responders had prior cGvHD (p = 0.073). The results demonstrate, that the currently proposed vaccination strategy leads to seroprotection in the majority of alloHSCT patients.  相似文献   
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ObjectivesThis study aimed to estimate prehospital delay and to identify the factors associated with the late arrival of patients with ischemic stroke at the Souss Massa Regional Hospital Center in Morocco.Patients and methodsAn observational, prospective, cross-sectional study was conducted from March 2019 to September 2019 in the Souss Massa regional hospital center, which is a public hospital structure. A questionnaire was administered to patients with ischemic stroke and to bystanders (family or others), while clinical and paraclinical data were collected from medical records. Univariate and multivariate logistic regression analyses were used to identify the factors associated with delayed arrival at emergency department.ResultsA total of 197 patients and 197 bystanders who fulfilled the criteria for the study were included. The median time from symptom onset to hospital arrival was 6 hours (IQR, 4–16). Multiple regression analysis showed that illiteracy (OR 38.58; CI95%: 3.40–437.27), waiting for symptoms to disappear (patient behavior) (OR 11.24; CI95%: 1.57–80.45), deciding to go directly to the hospital (patient behavior) (OR 0.07; CI95%: 0.01–0.57), bystander's knowledge that stroke is a disease requiring urgent care within a limited therapeutic window (OR 0.005; CI95%: 0.00–0.36), and direct admission without reference (OR 0.005; CI95%: 0.00–0.07), were independently associated with late arrival (> 4.5 hours) of patients with acute ischemic stroke. In addition, illiteracy (OR 24.62; CI95%: 4.37–138.69), vertigo and disturbance of balance or coordination (OR 0.14; CI95%: 0.03–0.73), the relative's knowledge that stroke is a disease requiring urgent care and within a limited therapeutic window (OR 0.03; CI95%: 0.00–0.22), calling for an ambulance (relative's behavior) (OR 0.16; CI95%: 0.03–0.80), distance between 50 and 100 km (OR 10.16; CI95%: 1.16–89.33), and direct admission without reference (OR 0.03; CI95%: 0.00–0.14), were independently associated with late arrival (> 6 hours) of patients with acute ischemic stroke.ConclusionPatient behavior, bystander knowledge and direct admission to the competent hospital for stroke care are modifiable factors potentially useful for reducing onset-to-door time, and thereby increasing the implementation rates of acute stroke therapies.  相似文献   
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医用化学是医学院校一门重要的基础必修课程,内容多为知识理解型,这导致了学生兴趣薄弱,学习效果欠佳。因此,需要通过改革传统"灌输式"课堂授课方式,让学生真正参与到教学活动中。BOPPPS教学模式分为导言、学习目标、前测、参与式学习、后测和总结六个环节。突出"以学生为中心"的教学理念,遵循教学活动的客观规律。在医用化学课程的教学过程中引入BOPPPS教学,能够有效提高学生的课堂参与度,增强学生的学习动力,培养学生独立思考、自主学习的能力。  相似文献   
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目的 研制用于核事故放射性污染伤员空运后送防护服。方法 根据放射性污染伤员的后送救护和污染防护要求,选用防污材料,设计结构布局,在演练行动中论证该防护服的合理性和实用并加以改进。结果 该型防护服材料具有较好的防渗透、耐腐蚀等理化特性,整体采用连体式结构,对伤员体表覆盖率达到97%,设计6个医学操作窗口和体侧游离拉链,达到了有效防止伤员体表放射性污染扩散和方便医疗救护的效果。结论 完成了放射性污染伤员空运后送防护服的研制,可满足核事故救援行动中伤员转运需要。  相似文献   
110.

Purpose

Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.

Methods and Materials

First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.

Results

The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.

Conclusions

The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target.  相似文献   
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