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131.
To investigate the dynamic compressive properties of concrete after high temperature and rapid cooling, an experimental study was carried out by considering five temperatures and four strain rates. The coupling effect of high temperature and strain rate on concrete damage morphology and mechanical parameters was comparatively analyzed. The main conclusions are as follows: the compressive damage morphology of concrete is affected by strain rate development trends of significant variability under different temperature conditions. As the strain rate increases, the compressive stress and elastic modulus of concrete are gradually increased. As the temperature increases, the increase in compressive stress is gradually reduced by the strain rate. For the temperatures of 20 °C and 800 °C, the increase in compressive stress by the strain rate is 38.69% and 7.78%, respectively. Meanwhile, SEM and CT scanning technology were applied to examine the mechanism of the effect of high temperature and strain rate on the mechanical properties of concrete from the microscopic perspective, and the corresponding constitutive model was proposed.  相似文献   
132.
The present study aimed to evaluate the postoperative complications and the impact of an enhanced recovery programme in patients who underwent primary surgery (including extensive upper abdominal surgery) for epithelial ovarian carcinoma (EOC). All patients with stage I–IV ovarian carcinoma who underwent primary surgery were identified, and postoperative complications were evaluated and graded according to the Clavien-Dindo classification. Of 161 patients, 46 (28.57%) underwent surgical staging, 27 (16.77%) standard cytoreduction, 12 (7.45%) en bloc debulking and 76 (47.20%) extraradical debulking. A total of 157 patients (97.52%) achieved optimal tumor reduction (<1 cm). The mean postoperative hospitalization time was 17.33±11.29 days after completion of the initial postoperative chemotherapy (IPC), and the IPC interval was 16.22±10.09 days. A total of 13 patients (8.07%) had grade 3 complications (9 with wound dehiscence, 3 with digestive tract leakage and 1 with a bladder fistula). A total of 2 patients (1.24%) had grade 4–5 complications [1 patient with severe pneumonia returned to the intensive care unit (ICU) for tracheotomy and respiration rehabilitation; the other patient died of septicemia on day 19]. The multivariate analysis of the preoperative factors revealed that a human epididymis protein 4 (HE4) level of ≥717 pM (P=0.015) and Federation International of Gynecology and Obstetrics (FIGO) stage IV (P=0.004; compared with stage IIIC) were associated with grade 3–5 complications. The bootstrap analysis revealed that a cancer antigen 125 (CA125) level of ≥1,012 U/ml (P=0.034), a HE4 level of ≥717 pM (P=0.007) and FIGO stage IV (P=0.002; compared with stage IIIC) were significantly associated with grade 3–5 complications. Meanwhile, the multivariate analysis of the postoperative factors did not reveal any risk factors associated with grade 3–5 complications; the bootstrap analysis revealed that only transfer to the ICU after surgery (P=0.026) was significantly associated with grade 3–5 complications. In conclusion, the study found that application of enhanced recovery after surgery protocols is feasible in patients with EOC, especially in those undergoing advanced extensive upper abdominal surgery, and CA125, HE4 and FIGO stage IV were related with the occurrence of adverse perioperative outcomes.  相似文献   
133.
背景 严重精神障碍患者危险行为发生率较一般人群更高,我国对社区严重精神障碍患者危险行为发生风险的预测研究尚不多见,尤其缺乏除传统预测方法之外的数据挖掘技术预测模型的研究和比较。目的 采用Logistic回归分析及分类决策树构建社区严重精神障碍患者危险行为发生风险的预测模型,检验分类决策树模型是否优于Logistic回归模型。方法 于2023年12月,选取2013年—2022年随访记录完整的11 484名社区严重精神障碍在管患者,按8∶2随机分为训练集(n=9 186)与测试集(n=2 298)。在训练集中,分别使用Logistic回归分析和分类决策树建立预测模型,在测试集评价模型的区分度和校准度。结果 1 115例(9.71%)严重精神障碍患者在随访期间出现危险行为。Logistic回归分析结果显示,城市户籍、贫困、有监护人、精神残疾、危险行为史阳性、自知力不全、自知力缺失、有阳性症状是患者发生危险行为的危险因素(OR=1.778、1.459、2.719、1.483、3.890、1.423、2.528、2.124,P均<0.01);年龄≥60岁、受过教育、医嘱无需用药以及社会功...  相似文献   
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PurposeTerlipressin improves renal function in patients with septic shock. However, the mechanism remains unclear. Here, we aimed to evaluate the effects of terlipressin on renal perfusion in patients with septic shock.Materials and MethodsThis pilot study enrolled patients with septic shock in the intensive care unit of the tertiary hospital from September 2019 to May 2020. We randomly assigned patients to terlipressin and usual care groups using a 1:1 ratio. Terlipressin was intravenously pumped at a rate of 1.3 μg/kg/hour for 24 h. We monitored renal perfusion using renal contrast-enhanced ultrasound (CEUS). The primary outcome was peak sonographic signal intensity (a renal perfusion parameter monitored by CEUS) at 24 h after enrollment.Results22 patients were enrolled in this study with 10 in the terlipressin group and 12 in the usual care group. The baseline characteristics of patients between the two groups were comparable. The peak sonographic signal intensity at 24 h after enrollment in the terlipressin group (60.5 ± 8.6 dB) was significantly higher than that in the usual care group (52.4 ± 7.0 dB; mean difference, 7.1 dB; 95% CI, 0.4–13.9; adjusted p = .04). Patients in the terlipressin group had a lower time to peak, heart rates, norepinephrine dose, and a higher stroke volume at 24 h after enrollment. No significant difference in the urine output within 24 h and incidence of acute kidney injury within 28 days was found between the two groups.ConclusionsTerlipressin improves renal perfusion, increases stroke volume, and decreases norepinephrine dose and heart rates in patients with septic shock.  相似文献   
137.
BackgroundOn May 18, 2020, the New York State Department of Health implemented a statewide flavor ban to prohibit the sales of all flavored vapor products, except for tobacco or any other authorized flavor.ObjectiveThis study aims to investigate the discussion changes in e-cigarette–related tweets over time with the implementation of the New York State flavor ban.MethodsThrough the Twitter streaming application programming interface, 59,883 e-cigarette–related tweets were collected within the New York State from February 6, 2020, to May 17, 2020 (period 1, before the implementation of the flavor ban), May 18, 2020-June 30, 2020 (period 2, between the implementation of the flavor ban and the online sales ban), July 1, 2020-September 15, 2020 (period 3, the short term after the online sales ban), and September 16, 2020-November 30, 2020 (period 4, the long term after the online sales ban). Sentiment analysis and topic modeling were conducted to investigate the changes in public attitudes and discussions in e-cigarette–related tweets. The popularity of different e-cigarette flavor categories was compared before and after the implementation of the New York State flavor ban.ResultsOur results showed that the proportion of e-cigarette–related tweets with negative sentiment significantly decreased (4305/13,246, 32.5% vs 3855/14,455, 26.67%, P<.001), and tweets with positive sentiment significantly increased (5246/13,246, 39.6% vs 7038/14,455, 48.69%, P<.001) in period 4 compared to period 3. “Teens and nicotine products” was the most frequently discussed e-cigarette–related topic in the negative tweets. In contrast, “nicotine products and quitting” was more prevalent in positive tweets. The proportion of tweets mentioning mint and menthol flavors significantly increased right after the flavor ban and decreased to lower levels over time. The proportions of fruit and sweet flavors were most frequently mentioned in period 1, decreased in period 2, and dominated again in period 4.ConclusionsThe proportion of e-cigarette–related tweets with different attitudes and frequently discussed flavor categories changed over time after the implementation of the New York State ban of flavored vaping products. This change indicated a potential impact of the flavor ban on public discussions of flavored e-cigarettes.  相似文献   
138.
Thyroid hormone resistance syndrome (THRS) is a rare disease characterized by reduced sensitivity to thyroid hormones. Mutations in the thyroid hormone receptor beta (THRB) gene are considered as contributing to the pathogenesis. This report describes a Chinese pedigree with THRS and Hashimoto’s thyroiditis (HT) due to novel point mutation in the 11th exon of the THRB gene (c. 1378 G > A). The proband complained of goitre with increased thyroid hormone and normal thyroid stimulating hormone levels. Gene sequencing was performed to confirm the diagnosis. HT was also diagnosed based on positive thyroid autoantibodies and diffuse, grid-like changes in the thyroid on ultrasound examination. Additionally, a comprehensive examination of the proband’s pedigree was conducted. The patient’s father exhibited the same gene mutation site and was diagnosed with THRS and HT. No mutation site was detected in three patients with HT only and three healthy volunteers. Thus, gene sequencing should be considered the gold standard for diagnosing THRS. Furthermore, treatment should be individualized to control the patient’s symptoms rather than normalizing thyroid hormone levels. Further studies that determine the relationship between THRS and TH are warranted.  相似文献   
139.
目的 比较修复楔状缺损时制备固位形及不同粘结剂对临床疗效的影响.方法 选择口内至少4颗楔状缺损的患者89例,609颗患牙,同一患者分别采用四种方法修复患牙(固位形+两步法自酸蚀牙本质粘结系统Clearfil SE Bond;固位形+一步法自酸蚀牙本质粘结系统iBond;无固位形+两步法自酸蚀牙本质粘结系统Clearfil SE Bond;无固位形+一步法自酸蚀牙本质粘结系统iBond),采用自身对照的方法进行为期1年的临床观察.结果 固位形组的成功率明显高于无固位形组,两者差异有统计学意义;无固位形组中两步法自酸蚀牙本质粘结系统Clearfil SE Bond组的成功率高于一步法自酸蚀牙本质粘结系统iBond组,两者差异有统计学意义,但二者在边缘密闭性和术后敏感方面差异没有统计学意义.结论 修复楔状缺损时,制备固位形有助于提高疗效;两步法自酸蚀牙本质粘结系统Clearfil SE Bond较一步法自酸蚀牙本质粘结系统iBond具有更高的粘结强度.  相似文献   
140.
目的 探究赶黄草水煎液在体外对金黄色葡萄球菌(SA)和耐甲氧西林金黄色葡萄球菌生物膜(MRSA)形成的影响。方法 采用微量肉汤稀释法测定赶黄草水煎液对金黄色葡萄球菌和耐甲氧西林金黄色葡萄球菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC),根据MIC和MBC绘制杀菌曲线,采用结晶紫染色法和激光共聚焦观察赶黄草水煎液对SA和MRSA生物膜形成的影响,并通过测定胞外多糖和胞外DNA的含量研究赶黄草水煎液破坏SA和MRSA生物膜的作用方式。结果 赶黄草水煎液对SA的MIC和MBC分别为1.36和2.71 mg/mL,对MRSA的MIC和MBC为2.71和5.73 mg/mL;赶黄草水煎液可使SA和MRSA均生长受到抑制,抑制生物膜的形成、减少胞外多糖和胞外DNA的释放。结论 赶黄草水煎液对SA和MRSA具有良好的抑菌作用,可通过抑制胞外多糖和DNA的分泌破坏生物膜的形成。  相似文献   
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